[REL] bump to v0.24.0

part of #330

COPYRIGHT

@@ -0,0 +1,14 @@
+
+Most of the files are
+
+  Copyright (c) 2004-2015 Odoo S.A.
+
+Many files also contain contributions from third
+parties. In this case the original copyright of
+the contributions can be traced through the
+history of the source version control system.
+
+When that is not the case, the files contain a prominent
+notice stating the original copyright and applicable
+license, or come with their own dedicated COPYRIGHT
+and/or LICENSE file.

README.md

@@ -1,19 +1,74 @@
 <h1 align="center">🦉 <a href="https://odoo.github.io/owl/">Odoo Web Library</a> 🦉</h1>
 
-_A web framework for structured, dynamic and maintainable applications_
+_A no nonsense web framework for structured, dynamic and maintainable applications_
 
 ## Project Overview
 
-The Odoo Web Library (OWL) is a small
-UI framework intended to be the basis for the [Odoo](https://www.odoo.com/) Web Client, and hopefully many
-other Odoo related projects. OWL's main feature is a _declarative component system_, with QWeb as a template engine, asynchronous rendering, and an underlying virtual dom.
+The Odoo Web Library (OWL) is a smallish (~18kb gzipped) UI framework intended to
+be the basis for the [Odoo](https://www.odoo.com/) Web Client. Owl is a modern
+framework, written in Typescript, taking the best ideas from React and Vue in a
+simple and consistent way. Owl's main features are:
 
-**Try it online!** An online playground is available at [https://odoo.github.io/owl/playground](https://odoo.github.io/owl/playground) to let you experiment with the OWL framework.
+- a declarative component system,
+- a reactivity system based on hooks,
+- a store implementation (for state management),
+- a small frontend router
 
-## OWL's Design Principles
+Owl components are defined with ES6 classes, they use QWeb templates, an underlying
+virtual dom, integrates beautifully with hooks, and the rendering is asynchronous.
+
+**Try it online!** An online playground is available at [https://odoo.github.io/owl/playground](https://odoo.github.io/owl/playground) to let you experiment with the Owl framework. There
+are some code examples to showcase some interesting features.
+
+Owl is currently mostly stable.  Possible future changes are explained in the
+[roadmap](roadmap.md).
+
+## Example
+
+Here is a short example to illustrate interactive components:
+
+```javascript
+import { Component, QWeb, useState } from "owl";
+import { xml } from "owl/tags";
+
+class Counter extends Component {
+  static template = xml`
+    <button t-on-click="increment">
+      Click Me! [<t t-esc="state.value"/>]
+    </button>`;
+
+  state = useState({ value: 0 });
+
+  increment() {
+    this.state.value++;
+  }
+}
+
+class App extends Component {
+  static template = xml`
+    <div>
+      <span>Hello Owl</span>
+      <Counter />
+    </div>`;
+
+  static components = { Counter };
+}
+
+const app = new App({ qweb: new QWeb() });
+app.mount(document.body);
+```
+
+Note that the counter component is made reactive with the [`useState`](doc/hooks.md#usestate)
+hook. Also, all examples here uses the `xml` helper to define inline templates.
+But this is not mandatory, many applications will load templates separately.
+
+More interesting examples can be found on the
+[playground](https://odoo.github.io/owl/playground) application.
+
+## Design Principles
 
 OWL is designed to be used in highly dynamic applications where changing
-requirements are common, code needs to be maintained by large teams.
+requirements are common and code needs to be maintained by large teams.
 
 - **XML based**: templates are based on the XML format, which allows interesting
   applications. For example, they could be stored in a database and modified
@@ -26,70 +81,192 @@ requirements are common, code needs to be maintained by large teams.
   for various reasons (security/deployment/dynamic modules/specific assets tools),
   it is not ok to use standard web tools based on `npm`.
 
-Owl is not designed to be fast or small (even though it is quite good on those
-two topics). If you are interested in a comparison with React or Vue, you will
+Owl is not designed to be fast nor small (even though it is quite good on those
+two topics). It is a no nonsense framework to build applications. There is only
+one way to define components (with classes).
+
+If you are interested in a comparison with React or Vue, you will
 find some more information [here](doc/comparison.md).
 
-## Example
+## Documentation
 
-Here is a short example to illustrate interactive widgets:
+A complete documentation for Owl can be found here:
 
-```xml
-<templates>
-  <button t-name="Counter" t-on-click="increment">
-    Click Me! [<t t-esc="state.value"/>]
-  </button>
-</templates>
-```
+- [Main documentation page](doc/readme.md).
 
-```javascript
-class Counter extends owl.Component {
-  state = { value: 0 };
+The most important sections are:
 
-  increment() {
-    this.state.value++;
-  }
-}
+- [Quick Start](doc/quick_start.md)
+- [Component](doc/component.md)
+- [Hooks](doc/hooks.md)
 
-const qweb = new owl.QWeb(TEMPLATES);
-const counter = new Counter({ qweb });
-counter.mount(document.body);
-```
-
-Note that we assume here that the xml templates are available in the `TEMPLATES`
-string. More interesting examples can be found on the
-[playground](https://odoo.github.io/owl/playground) application.
+Found an issue in the documentation? A broken link? Some outdated information?
+Submit a PR!
 
 ## Installing/Building
 
 If you want to use a simple `<script>` tag, the last release can be downloaded here:
 
-- [owl-0.15.0.js](https://github.com/odoo/owl/releases/download/v0.15.0/owl.js)
-- [owl-0.15.0.min.js](https://github.com/odoo/owl/releases/download/v0.15.0/owl.min.js)
+- [owl-0.24.0.js](https://github.com/odoo/owl/releases/download/v0.24.0/owl.js)
+- [owl-0.24.0.min.js](https://github.com/odoo/owl/releases/download/v0.24.0/owl.min.js)
 
 Some npm scripts are available:
 
-| Command               | Description                                                                  |
-| --------------------- | ---------------------------------------------------------------------------- |
-| `npm install`         | install every dependency required for this project                           |
-| `npm run build`       | build a bundle of _owl_ in the _/dist/_ folder                               |
-| `npm run minify`      | minify the prebuilt owl.js file                                              |
-| `npm run test`        | run all tests                                                                |
-| `npm run test:watch`  | run all tests, and keep a watcher                                            |
-| `npm run tools`       | build tools applications, start a static server (see [here](doc/tooling.md)) |
-| `npm run tools:watch` | same as `tools`, but with a watcher to rebuild owl                           |
+| Command          | Description                                        |
+| ---------------- | -------------------------------------------------- |
+| `npm install`    | install every dependency required for this project |
+| `npm run build`  | build a bundle of _owl_ in the _/dist/_ folder     |
+| `npm run minify` | minify the prebuilt owl.js file                    |
+| `npm run test`   | run all (owl) tests                                |
 
-## Documentation
+## Quick Overview
 
-The complete documentation can be found [here](doc/readme.md). The most important sections are:
+Owl components in an application are used to define a (dynamic) tree of components.
 
-- [Quick Start](doc/quick_start.md)
-- [Component](doc/component.md)
-- [QWeb](doc/qweb.md)
+```
+        Root
+        /   \
+       A     B
+      / \
+     C   D
+```
 
-Found an issue in the documentation? A broken link? Some outdated information?
-Submit a PR!
+**Environment:** the root component is special: it is created with an environment,
+which should contain a `QWeb` instance. The environment is then automatically
+propagated to each sub components (and accessible in the `this.env` property).
+
+```js
+const env = { qweb: new QWeb() };
+const app = new App(env);
+app.mount(document.body);
+```
+
+The environment is mostly static. Each application is free to add anything to
+the environment, which is very useful, since this can be accessed by each sub
+component. Some good use case for that is some configuration keys, session
+information or generic services (such as doing rpcs, or accessing local storage).
+Doing it this way means that components are easily testable: we can simply
+create a test environment with mock services.
+
+**State:** each component can manage its own local state. It is a simple ES6
+class, there are no special rules:
+
+```js
+class Counter extends Component {
+  static template = xml`
+    <button t-on-click="increment">
+      Click Me! [<t t-esc="state.value"/>]
+    </button>`;
+
+  state = { value: 0 };
+
+  increment() {
+    this.state.value++;
+    this.render();
+  }
+}
+```
+
+The example above shows a component with a local state. Note that since there
+is nothing magical to the `state` object, we need to manually call the `render`
+function whenever we update it. This can quickly become annoying (and not
+efficient if we do it too much). There is a better way: using the `useState`
+hook, which transforms an object into a reactive version of itself:
+
+```js
+const { useState } = owl.hooks;
+
+class Counter extends Component {
+  static template = xml`
+    <button t-on-click="increment">
+      Click Me! [<t t-esc="state.value"/>]
+    </button>`;
+
+  state = useState({ value: 0 });
+
+  increment() {
+    this.state.value++;
+  }
+}
+```
+
+Note that the `t-on-click` handler can even be replaced by an inline statement:
+
+```xml
+    <button t-on-click="state.value++">
+```
+
+**Props:** sub components often needs some information from their parents. This
+is done by adding the required information to the template. This will then be
+accessible by the sub component in the `props` object. Note that there is an
+important rule here: the information contained in the `props` object is not
+owned by the sub component, and should never be modified.
+
+```js
+class Child extends Component {
+  static template = xml`<div>Hello <t t-esc="props.name"/></div>`;
+}
+
+class Parent extends Component {
+  static template = xml`
+    <div>
+        <Child name="'Owl'" />
+        <Child name="'Framework'" />
+    </div>`;
+  static components = { Child };
+}
+```
+
+**Communication:** there are multiple ways to communicate information between
+components. However, the two most important ways are the following:
+
+- from parent to children: by using `props`,
+- from a children to one of its parent: by triggering events.
+
+The following example illustrate both mechanisms:
+
+```js
+class OrderLine extends Component {
+  static template = xml`
+    <div t-on-click="add">
+        <div><t t-esc="props.line.name"/></div>
+        <div>Quantity: <t t-esc="props.line.quantity"/></div>
+    </div>`;
+
+  add() {
+    this.trigger("add-to-order", { line: props.line });
+  }
+}
+
+class Parent extends Component {
+  static template = xml`
+    <div t-on-add-to-order="addToOrder">
+        <OrderLine
+            t-foreach="orders"
+            t-as="line"
+            line="line" />
+    </div>`;
+  static components = { OrderLine };
+  orders = useState([{ id: 1, name: "Coffee", quantity: 0 }, { id: 2, name: "Tea", quantity: 0 }]);
+
+  addToOrder(event) {
+    const line = event.detail.line;
+    line.quantity++;
+  }
+}
+```
+
+In this example, the `OrderLine` component trigger a `add-to-order` event. This
+will generate a DOM event which will bubble along the DOM tree. It will then be
+intercepted by the parent component, which will then get the line (from the
+`detail` key) and then increment its quantity. See the section on [event handling](doc/component.md#event-handling)
+for more details on how events work.
+
+Note that this example would have also worked if the `OrderLine` component
+directly modifies the `line` object. However, this is not a good practice: this
+only works because the `props` object received by the child component is reactive,
+so the child component is then coupled to the parents implementation.
 
 ## License
 
-OWL is [GPL licensed](./LICENSE).
+OWL is [LGPL licensed](./LICENSE).

doc/animations.md

@@ -30,7 +30,7 @@ btn {
 }
 ```
 
-will produce a nice flash effect whenever the user click (or activate with the
+will produce a nice flash effect whenever the user clicks (or activates with the
 keyboard) the button.
 
 ## CSS Transitions
@@ -47,7 +47,7 @@ the lifetime of a node. Since this is not easy to do by hand, Owl `t-transition`
 directive is there to help.
 
 Whenever a node has a `t-transition` directive, with a `name` value, the following
-will happen:
+sequence of events will happen:
 
 At node insertion:
 
@@ -87,10 +87,9 @@ For example, a simple fade in/out effect can be done with this:
 }
 ```
 
-The `t-transition` directive can be combined with `t-widget`.
+The `t-transition` directive can be applied on a node element or on a component.
 
 Notes:
 
-- more information on animations are available [here](animations.md).
-- Owl does not support more than one transition on a single node, so the
-  `t-transition` expression must be a single value (i.e. no space allowed)
+Owl does not support more than one transition on a single node, so the
+`t-transition` expression must be a single value (i.e. no space allowed).

doc/comparison.md

@@ -3,30 +3,59 @@
 OWL, React and Vue have the same main feature: they allow developers to build
 declarative user interfaces. To do that, all these frameworks uses a virtual dom. However, there are still obviously many differences.
 
-In this page, we try to highlight some of these differences. Obviously, some
+In this page, we try to highlight some of these differences. Obviously, a lot of
 effort was done to be fair. However, if you disagree with some of the points
 discussed, feel free to open an issue/submit a PR to correct this text.
 
 ## Content
 
 - [Size](#size)
+- [Class Based](#class-based)
 - [Tooling/Build Step](#toolingbuild-step)
 - [Templating](#templating)
 - [Asynchronous rendering](#asynchronous-rendering)
 - [Reactiveness](#reactiveness)
 - [State Management](#state-management)
+- [Hooks](#hooks)
 
 ## Size
 
 OWL is intended to be small and to work at a slightly lower level of abstraction
 than React and Vue. Also, jQuery is not the same kind of framework, but it is interesting to compare.
 
-| Framework                | Size (minified) | Size (minified, gzipped) |
-| ------------------------ | --------------- | ------------------------ |
-| OWL                      | 32kb            | 11kb                     |
-| Vue + VueX               |                 | 30kb                     |
-| React + ReactDOM + Redux |                 | 40kb                     |
-| jQuery                   | 86kb            | 30kb                     |
+| Framework                | Size (minified, gzipped) |
+| ------------------------ | ------------------------ |
+| OWL                      | 18kb                     |
+| Vue + VueX               | 30kb                     |
+| Vue + VueX + Vue Router  | 39kb                     |
+| React + ReactDOM + Redux | 40kb                     |
+| jQuery                   | 30kb                     |
+
+Note that those comparisons are not entirely fair, because we do not compare
+the same exact set of features. For example, VueX and Vue Router support more
+advanced use cases.
+
+## Class Based
+
+Both React and Vue moved away from defining components with classes. They prefer
+a more functional approach, in particular, with the new `hooks` mechanisms.
+
+This has some advantages and disadvantages. But the end result is that React
+and Vue both offers multiple different ways of defining new components. In
+contrast, Owl has only one mechanism: class-based components. We believe that Owl
+components are fast enough for all our usecases, and making it as simple as
+possible for developers is more valuable (for us).
+
+Also, functions or class based components are more than just syntax. Functions
+comes with a mindset of composition and class are about inheritance. Clearly,
+both of these are important mechanisms for reusing code. Also, one does not
+exclude the other.
+
+It certainly looks like the world of UI frameworks is moving toward composition,
+for many very good reasons. Owl is still good at composition (for example,
+Owl supports slots, which is the primary mechanism to make generic reusable
+components). But it can also use inheritance (and this is very important since
+templates can also be inherited with `xpaths` transformations).
 
 ## Tooling/Build step
 
@@ -38,14 +67,24 @@ be used by simply adding a script tag to a page.
 <script src="owl.min.js" />
 ```
 
-In comparison, React encourages using JSX,
-which necessitate a build step, and most Vue applications uses single file
-components, which also necessitate a build step.
+In comparison, React encourages using JSX, which necessitate a build step, and
+most Vue applications uses single file components, which also necessitate a build step.
 
 On the flipside, external tooling may make it harder to use in some case, but it
 also brings a lot of benefits. And React/Vue have both a large ecosystem.
 
-### Templating
+Note that since Owl is not dependant on any external tool nor libraries, it is
+very easy to integrate into any build toolchain. Also, since we cannot rely on
+additional tools, we made a lot of effort to make the most of the web platform.
+
+For example, Owl uses the standard `xml` parser that comes with every browser.
+Because of that, Owl did not have to write its own template parser. Another
+example is the [`xml`](tags.md#xml-tag) tag helper function, which makes use of
+native template literals to allow in a natural way to write `xml` templates
+directly in the javascript code. This can be easily integrated with editor
+plugins to have autocompletion inside the template.
+
+## Templating
 
 OWL uses its own QWeb engine, which compiles templates on the
 frontend, as they are needed. This is extremely convenient for our use case, in
@@ -67,7 +106,8 @@ into javascript functions. Note that Vue has a separate build which includes the
 template compiler.
 
 In contrast, most React applications do not use a templating language, but write
-some JSX code, which is precompiled into plain JavaScript by a build step.
+some JSX code, which is precompiled into plain JavaScript by a build step. This
+example is done with the (kind of outdated) React class system:
 
 ```jsx
 class Clock extends React.Component {
@@ -86,22 +126,36 @@ This has the advantage of having the full power of Javascript, but is less
 structured than a template language. Note that the tooling is quite impressive:
 there is a syntax highlighter for jsx here on github!
 
+By comparison, here is the equivalent Owl component, written with the
+[`xml`](tags.md#xml-tag) tag helper:
+
+```js
+class Clock extends Component {
+  static template = xml`
+      <div>
+        <h1>Hello, world!</h1>
+        <h2>It is {props.date.toLocaleTimeString()}.</h2>
+      </div>
+    `;
+}
+```
+
 ## Asynchronous Rendering
 
 This is actually a big difference between OWL and React/Vue: components in OWL
 are totally asynchronous. They have two asynchronous hooks in their lifecycle:
 
-- `willStart` (before the widget starts rendering)
+- `willStart` (before the component starts rendering)
 - `willUpdateProps` (before new props are set)
 
 Both these methods can be implemented and return a promise. The rendering will
 then wait for these promises to be completed before patching the DOM. This is
-useful for some use cases: for example, a widget may want to fetch an external
-library (a calendar widget may need a specialized calendar rendering library),
+useful for some use cases: for example, a component may want to fetch an external
+library (a calendar component may need a specialized calendar rendering library),
 in its willStart hook.
 
 ```javascript
-class MyCalendarWidget extends owl.Component {
+class MyCalendarComponent extends owl.Component {
     ...
 
     willStart() {
@@ -115,12 +169,14 @@ This may be dangerous (to stop the rendering waiting for the network), but it is
 extremely powerful as well, as demonstrated by the Odoo Web Client.
 
 Lazy loading static libraries can obviously be done with React/Vue, but it is
-more convoluted.
+more convoluted. For example, in Vue, you need to use a dynamic import keyword
+that needs to be transpiled at build time in order for the component to be loaded
+asynchronously (see [the documentation](https://vuejs.org/v2/guide/components-dynamic-async.html#Async-Components)).
 
 ## Reactiveness
 
 React has a simple model: whenever the state changes, it is
-replaced with a new state (via the setState method). Then, the DOM is patched.
+replaced with a new state (via the `setState` method). Then, the DOM is patched.
 This is simple, efficient, and a little bit awkward to write.
 
 Vue is a little bit different: it replace magically the properties in the state
@@ -128,8 +184,10 @@ by getters/setters. With that, it can notify components whenever the state that
 they read was changed.
 
 Owl is closer to vue: it also tracks magically the state properties, but it does
-only increment a counter whenever it changes (and a _deep_ counter for each of
-its parents). This assumes that the state is actually a tree.
+only increment an internal counter whenever it changes. Note that it is done
+with a `Proxy`, which means that it is totally transparent to the developers.
+Adding new keys is supported. Once any part of the state has been changed, a
+rendering is scheduled in the next microtask tick (promise queue).
 
 ## State Management
 
@@ -190,7 +248,97 @@ keeps track of who get data, and retrigger a render when it was changed.
 
 **Owl**
 
-Owl store is a little bit like a mix of redux and vuex: it has mutations and
-actions, like VueX, it keeps track of the state changes, but it does not notify
-a component when the state changes. Instead, components need to connect to the
-store like in redux, with a function that will listen to the relevant state.
+Owl store is a little bit like a mix of redux and vuex: it has actions (but not
+mutations), and like VueX, it keeps track of the state changes. However, it does
+not notify a component when the state changes. Instead, components need to connect
+to the store like in redux, with the `useStore` hook (see the [store documentation](store.md#connecting-a-component)).
+
+```javascript
+const actions = {
+  increment({ state }, val) {
+    state.counter.value += val;
+  }
+};
+
+const state = {
+  counter: { value: 0 }
+};
+const store = new owl.Store({ state, actions });
+
+class Counter extends Component {
+  static template = xml`
+      <button t-name="Counter" t-on-click="dispatch('increment')">
+        Click Me! [<t t-esc="counter.value"/>]
+      </button>`;
+  counter = useStore(state => state.counter);
+  dispatch = useDispatch();
+}
+
+const counter = new Counter({ store, qweb });
+```
+
+## Hooks
+
+[Hooks](https://reactjs.org/docs/hooks-intro.html#motivation) recently took over
+the React world. They solve a lot of seemingly unconnected problems: attach
+reusable behavior to a component, in a composable way, extract stateful logic
+from a component or reuse stateful logic between component, without changing your
+component hierarchy.
+
+Here is an example of the React `useState` hook:
+
+```js
+import React, { useState } from "react";
+
+function Example() {
+  // Declare a new state variable, which we'll call "count"
+  const [count, setCount] = useState(0);
+
+  return (
+    <div>
+      <p>You clicked {count} times</p>
+      <button onClick={() => setCount(count + 1)}>Click me</button>
+    </div>
+  );
+}
+```
+
+Because of the way React designed the hooks API, they only work for functional
+components. But in that case, they really are powerful. Every major React library
+is in the process of redesigning their API with hooks (for example,
+[Redux](https://react-redux.js.org/next/api/hooks)).
+
+Vue 2 does not have hooks, but the Vue project is working on its next version,
+which will feature its new [composition API](https://vue-composition-api-rfc.netlify.com/).
+This work is based on the new ideas introduced by React hooks.
+
+From the way React and Vue introduce their hooks, it may look like hooks are not
+compatible with class components. However, this is not the case, as shown by
+Owl [hooks](hooks.md). They are inspired by both React and Vue. For example,
+the `useState` hook is named after React, but its API is closer to the `reactive`
+Vue hook.
+
+Here is what the `Counter` example above look like in Owl:
+
+```js
+import { Component, Owl } from "owl";
+import { xml } from "owl/tags";
+
+class Example extends Component {
+  static template = xml`
+      <div>
+        <p>You clicked {count.value} times</p>
+        <button t-on-click="increment">Click me</button>
+      </div>`;
+
+  count = useState({ value: 0 });
+
+  increment() {
+    this.state.value++;
+  }
+}
+```
+
+Since the Owl framework had hooks from early in its life, its main APIs
+are designed to be interacted with hooks from the start. For example, the
+`Context` and `Store` abstractions.

doc/context.md

@@ -0,0 +1,108 @@
+# 🦉 Context 🦉
+
+## Content
+
+- [Overview](#overview)
+- [Example](#example)
+- [Reference](#reference)
+  - [`Context`](#context)
+  - [`useContext`](#usecontext)
+
+## Overview
+
+The `Context` object provides a way to share data between an arbitrary number
+of components. Usually, data is passed from a parent to its children component,
+but when we have to deal with some mostly global information, this can be
+annoying, since each component will need to pass the information to each children,
+even though some or most of them will not use the information.
+
+With a `Context` object, each component can subscribe (with the `useContext` hook)
+to its state, and will be updated whenever the context state is updated.
+
+## Example
+
+Assume that we have an application with various components which needs to render
+differently depending on the size of the device. Here is how we could proceed
+to make sure that the information is properly shared. First, let us create a
+context, and add it to the environment:
+
+```js
+const deviceContext = new Context({ isMobile: true });
+const env = {
+  qweb: new QWeb(TEMPLATES),
+  deviceContext
+};
+```
+
+If we want to make it completely responsive, we need to update its value whenever
+the size of the screen is updated:
+
+```js
+const isMobile = () => window.innerWidth <= 768;
+window.addEventListener(
+  "resize",
+  owl.utils.debounce(() => {
+    const state = deviceContext.state;
+    if (state.isMobile !== isMobile()) {
+      state.isMobile = !state.isMobile;
+    }
+  }, 15)
+);
+```
+
+Then, each component that want can subscribe and render differently depending on the
+fact that we are in a mobile or desktop mode.
+
+```js
+class SomeComponent extends Component {
+  static template = xml`
+        <div>
+          <t t-if=device.isMobile>
+             some simplified user interface
+          </t>
+          <t t-else="1">
+             some more sopthisticated user interface
+          </t>
+    `;
+  device = useContext(this.env.deviceContext);
+}
+```
+
+## Reference
+
+### `Context`
+
+A `Context` object should be created with a state object:
+
+```js
+const someContext = new Context({ some: "key" });
+```
+
+Its state is now available in the `state` key:
+
+```js
+someContext.state.some = "other key";
+```
+
+This is the way some global code (such as the responsive code above) should
+read and update the context state. However, components should not ever read the
+context state directly from the context, they should instead use the `useContext`
+hook to properly register themselves to state changes.
+
+Note that the `Context` hook is different from the React version. For example,
+there is no concept of provider/consumer. So, the `Context` feature does not
+by itself allow the use of a different context state depending on the component
+place in the component tree. However, this functionality can be obtained, if
+necessary, with the use of sub environment.
+
+### `useContext`
+
+The `useContext` hook is the normal way for a component to register themselve
+to context state changes. The `useContext` method returns the context state:
+
+```js
+device = useContext(this.env.deviceContext);
+```
+
+It is a simple observed state (with an owl `Observer`), which contains the shared
+information.

doc/event_bus.md

@@ -5,7 +5,7 @@ parts of the code. Owl has a very simple bus class, which manages subscriptions,
 triggering events, and callbacks.
 
 ```js
-const bus = new owl.EventBus();
+const bus = new owl.core.EventBus();
 
 bus.on("some-event", null, function(...args) {
   console.log(...args);

doc/hooks.md

@@ -0,0 +1,422 @@
+# 🦉 Hooks 🦉
+
+## Content
+
+- [Overview](#overview)
+- [Example: Mouse Position](#example-mouse-position)
+- [Example: Autofocus](#example-autofocus)
+- [Reference](#reference)
+  - [One Rule](#one-rule)
+  - [`useState`](#usestate)
+  - [`onMounted`](#onmounted)
+  - [`onWillUnmount`](#onwillunmount)
+  - [`onWillPatch`](#onwillpatch)
+  - [`onPatched`](#onpatched)
+  - [`onWillStart`](#onwillstart)
+  - [`onWillUpdateProps`](#onwillupdateprops)
+  - [`useContext`](#usecontext)
+  - [`useRef`](#useref)
+  - [`useSubEnv`](#usesubenv)
+  - [`useStore`](#usestore)
+  - [`useDispatch`](#usedispatch)
+  - [`useGetters`](#usegetters)
+  - [Making customized hooks](#making-customized-hooks)
+
+## Overview
+
+Hooks were popularised by React as a way to solve the following issues:
+
+- help reusing stateful logic between components
+- help organizing code by feature in complex components
+- use state in functional components, without writing a class.
+
+Owl hooks serve the same purpose, except that they work for class components
+(note: React hooks do not work on class components, and maybe because of that,
+there seems to be the misconception that hooks are in opposition to class. This
+is clearly not true, as shown by Owl hooks).
+
+Hooks work beautifully with Owl components: they solve the problems mentioned
+above, and in particular, they are the perfect way to make your component
+reactive.
+
+## Example: mouse position
+
+Here is the classical example of a non trivial hook to track the mouse position.
+
+```js
+const { useState, onMounted, onWillUnmount } = owl.hooks;
+
+// We define here a custom behaviour: this hook tracks the state of the mouse
+// position
+function useMouse() {
+  const position = useState({ x: 0, y: 0 });
+
+  function update(e) {
+    position.x = e.clientX;
+    position.y = e.clientY;
+  }
+  onMounted(() => {
+    window.addEventListener("mousemove", update);
+  });
+  onWillUnmount(() => {
+    window.removeEventListener("mousemove", update);
+  });
+
+  return position;
+}
+
+// Main root component
+class App extends owl.Component {
+  static template = xml`
+    <div t-name="App">
+      <div>Mouse: <t t-esc="mouse.x"/>, <t t-esc="mouse.y"/></div>
+    </div>`;
+
+  // this hooks is bound to the 'mouse' property.
+  mouse = useMouse();
+}
+```
+
+Note that we use the prefix `use` for hooks, just like in React. This is just
+a convention.
+
+## Example: autofocus
+
+Hooks can be combined to create the desired effect. For example, the following
+hook combines the `useRef` hook with the `onPatched` and `onMounted` functions
+to create an easy way to focus an input whenever it appears in the DOM:
+
+```js
+function useAutofocus(name) {
+  let ref = useRef(name);
+  let isInDom = false;
+  function updateFocus() {
+    if (!isInDom && ref.el) {
+      isInDom = true;
+      ref.el.focus();
+    } else if (isInDom && !ref.el) {
+      isInDom = false;
+    }
+  }
+  onPatched(updateFocus);
+  onMounted(updateFocus);
+}
+```
+
+This hook takes the name of a valid `t-ref` directive, which should be present
+in the template. It then checks whenever the component is mounted or patched if
+the reference is not valid, and in this case, it will focus the node element.
+This hook can be used like this:
+
+```js
+class SomeComponent extends Component {
+  static template = xml`
+    <div>
+        <input />
+        <input t-ref="myinput"/>
+    </div>`;
+
+  constructor(...args) {
+    super(...args);
+    useAutofocus("myinput");
+  }
+}
+```
+
+## Reference
+
+### One rule
+
+There is only one rule: every hook for a component has to be called in the
+constructor (or in class fields):
+
+```js
+// ok
+class SomeComponent extends Component {
+  state = useState({ value: 0 });
+}
+
+// also ok
+class SomeComponent extends Component {
+  constructor(...args) {
+    super(...args);
+    this.state = useState({ value: 0 });
+  }
+}
+
+// not ok: this is executed after the constructor is called
+class SomeComponent extends Component {
+  async willStart() {
+    this.state = useState({ value: 0 });
+  }
+}
+```
+
+In a hook, the `Component.current` static property is the reference to the
+component instance that is currently being created. Hooks need to be called in
+the constructor to ensure that this reference is properly set.
+
+### `useState`
+
+The `useState` hook is certainly the most important hook for Owl components:
+this is what allows a component to be reactive, to react to state change.
+
+The `useState` hook has to be given an object or an array, and will return
+an observed version of it (using a `Proxy`).
+
+```javascript
+const { useState } = owl.hooks;
+
+class Counter extends owl.Component {
+  static template = xml`
+    <button t-on-click="increment">
+        Click Me! [<t t-esc="state.value"/>]
+    </button>`;
+
+  state = useState({ value: 0 });
+
+  increment() {
+    this.state.value++;
+  }
+}
+```
+
+### `onMounted`
+
+`onMounted` is not a user hook, but is a building block designed to help make useful
+abstractions. `onMounted` registers a callback, which will be called when the component
+is mounted (see example on top of this page).
+
+### `onWillUnmount`
+
+`onWillUnmount` is not a user hook, but is a building block designed to help make useful
+abstractions. `onWillUnmount` registers a callback, which will be called when the component
+is unmounted (see example on top of this page).
+
+### `onWillPatch`
+
+`onWillPatch` is not a user hook, but is a building block designed to help make useful
+abstractions. `onWillPatch` registers a callback, which will be called just
+before the component patched.
+
+### `onPatched`
+
+`onPatched` is not a user hook, but is a building block designed to help make useful
+abstractions. `onPatched` registers a callback, which will be called just
+after the component patched.
+
+### `onWillStart`
+
+`onWillStart` is an asynchronous hook. This means that the function registered
+in the hook will be run just before the component is first rendered and can return a
+promise, to express the fact that it is an asynchronous operation.
+
+Note that if there are more than one `onWillStart` registered callback, then they
+will all be run in parallel.
+
+It can be used to load some initial data. For example, the following hook will
+automatically load some data from the server, and return an object that will
+be ready whenever the component is rendered:
+
+```js
+function useLoader() {
+  const component = Component.current;
+  const record = useState({});
+  onWillStart(async () => {
+    const recordId = component.props.id;
+    Object.assign(record, await fetchSomeRecord(recordId));
+  });
+  return record;
+}
+```
+
+Note that this example does not update the record value whenever props are
+updated. For that situation, we need to use the `onWillUpdateProps` hook.
+
+### `onWillUpdateProps`
+
+Just like `onWillStart`, `onWillUpdateProps` is an asynchronous hook. It is
+designed to be run whenever the component props are updated. This could be
+useful to perform some asynchronous task such as fetching updated data.
+
+```js
+function useLoader() {
+  const component = Component.current;
+  const record = useState({});
+
+  async function updateRecord(id) {
+    Object.assign(record, await fetchSomeRecord(id));
+  }
+
+  onWillStart(() => updateRecord(component.props.id));
+  onWillUpdateProps(nextProps => updateRecord(nextProps.id));
+
+  return record;
+}
+```
+
+Note that if there are more than one `onWillUpdateProps` registered callback,
+then they will all be run in parallel.
+
+### `useContext`
+
+See [`useContext`](context.md#usecontext) for reference documentation.
+
+### `useRef`
+
+The `useRef` hook is useful when we need a way to interact with some inside part
+of a component, rendered by Owl. It can work either on a DOM node, or on a component,
+tagged by the `t-ref` directive:
+
+```xml
+<div>
+    <div t-ref="someDiv"/>
+    <SubComponent t-ref="someComponent"/>
+</div>
+```
+
+In this example, the component will be able to access the `div` and the component
+`SubComponent` using the `useRef` hook:
+
+```js
+class Parent extends Component {
+  subRef = useRef("someComponent");
+  divRef = useRef("someDiv");
+
+  someMethod() {
+    // here, if component is mounted, refs are active:
+    // - this.divRef.el is the div HTMLElement
+    // - this.subRef.comp is the instance of the sub component
+  }
+}
+```
+
+As shown by the example above, html elements are accessed by using the `el`
+key, and components references are accessed with `comp`.
+
+Note: if used on a component, the reference will be set in the `refs`
+variable between `willPatch` and `patched`.
+
+The `t-ref` directive also accepts dynamic values with string interpolation
+(like the [`t-attf-`](qweb.md#dynamic-attributes) and
+`t-component` directives). For example,
+
+```xml
+<div t-ref="component_{{someCondition ? '1' : '2'}}"/>
+```
+
+Here, the references need to be set like this:
+
+```js
+this.ref1 = useRef("component_1");
+this.ref2 = useRef("component_2");
+```
+
+References are only guaranteed to be active while the parent component is mounted.
+If this is not the case, accessing `el` or `comp` on it will return `null`.
+
+### `useSubEnv`
+
+The environment is sometimes useful to share some common information between
+all components. But sometimes, we want to _scope_ that knowledge to a subtree.
+
+For example, if we have a form view component, maybe we would like to make some
+`model` object available to all sub components, but not to the whole application.
+This is where the `useSubEnv` hook may be useful: it lets a component add some
+information to the environment in a way that only the component and its children
+can access it:
+
+```js
+class FormComponent extends Component {
+  constructor(...args) {
+    super(...args);
+    const model = makeModel();
+    useSubEnv({ model });
+  }
+}
+```
+
+The `useSubEnv` takes one argument: an object which contains some key/value that
+will be added to the parent environment. Note that it will extend, not replace
+the parent environment. And of course, the parent environment will not be
+affected.
+
+### `useStore`
+
+The `useStore` hook is the entry point for a component to connect to the store.
+See the [store documentation](store.md) for more information.
+
+### `useDispatch`
+
+The `useDispatch` hook is the way for components to get a reference to the store
+`dispatch` function. See the [store documentation](store.md) for more information.
+
+### `useGetters`
+
+The `useGetters` hook is the way for components to get a reference to the store
+getters. See the [store documentation](store.md) for more information.
+
+### Making customized hooks
+
+Hooks are a wonderful way to organize the code of a complex component by feature
+instead of by lifecycle methods. They are like mixins, except that they can be
+easily composed together.
+
+But, like every good things in life, hooks should be used with moderation. They are
+not the solution to every problem.
+
+- they may be overkill: if your component needs to perform some action specific
+  to itself (so, the specific code does not need to be shared), there is nothing
+  wrong with a simple class method:
+
+  ```js
+  // maybe overkill
+  class A extends Component {
+    constructor(...args) {
+      super(...args);
+      useMySpecificHook();
+    }
+  }
+
+  // ok
+  class B extends Component {
+    constructor(...args) {
+      super(...args);
+      this.performSpecificTask();
+    }
+  }
+  ```
+
+  Note that the second solution is easier to extend in sub components.
+
+- they may be harder to test: if a customized hook injects some external side
+  effect dependency, then it is harder to test without doing some non obvious
+  manipulation. For example, assume that we want to give a reference to a
+  router in a `useRouter` hook. We could do this:
+
+  ```js
+  const router = new Router(...);
+
+  function useRouter() {
+      return router;
+  }
+  ```
+
+  As you can see, this does not _hook_ into the internal of the component. It
+  simply returns a global object, which is difficult to mock.
+
+  A better way would be to do something like this: get the reference from the
+  environment.
+
+  ```js
+  function useRouter() {
+    return Component.current.env.router;
+  }
+  ```
+
+  This means that we give control to the application developer to create the
+  router, which is good, so they can set it up, subclass it, ... And then, to
+  test our components, we can just add a mock router in the environment.
+
+Note: the code above makes use of the `Component.current` property. This is the
+way hooks are able to get a reference to the component currently being created.

doc/misc.md

@@ -0,0 +1,23 @@
+# 🦉 Miscellaneous 🦉
+
+## `AsyncRoot`
+
+When this component is used, a new rendering sub tree is created, such that the
+rendering of that component (and its children) is not tied to the rendering of
+the rest of the interface. It can be used on an asynchronous component, to
+prevent it from delaying the rendering of the whole interface, or on a
+synchronous one, such that its rendering isn't delayed by other (asynchronous)
+components. Note that this directive has no effect on the first rendering, but
+only on subsequent ones (triggered by state or props changes).
+
+```xml
+<div t-name="ParentComponent">
+  <SyncChild />
+  <AsyncRoot>
+     <AsyncChild/>
+  </AsyncRoot>
+</div>
+```
+
+The `AsyncRoot` assumes that there is exactly one root node inside it. It can
+be a dom node or a component.

doc/observer.md

@@ -1,50 +1,52 @@
 # 🦉 Observer 🦉
 
-Owl need to be able to react to state changes. For example, whenever the state
-of a component is changed, we need to rerender it. To help with that, we have
-an Observer class. Its job is to observe some object state, and react to any
-change. To do that, it recursively replace all keys of the observed state by
-getters and setters.
+Owl needs to be able to react to state changes. For example, whenever the state
+of a component is changed, Owl needs to rerender it. To help with that, there is
+an Observer class. Its job is to observe the state of an object (or array), and
+to react to any change. The observer is implemented with the native `Proxy`
+object. Note that this means that it will not work on older browsers.
+
+Note that the `Observer` is used by the `useState` and `useContext` hooks. This
+is the way most Owl applications will create observers. For the majority of
+use cases, there is no need to directly instantiate an observer.
+
+## Example
 
 For example, this code will display `update` in the console:
 
 ```javascript
 const observer = new owl.Observer();
 observer.notifyCB = () => console.log("update");
-observer.observe(obj);
+const obj = observer.observe({ a: { b: 1 } });
 
-const obj = { a: { b: 1 } };
 obj.a.b = 2;
 ```
 
-## Technical Limitations
+This example shows that an observer can observe nested properties.
 
-Since the observer uses getters and setters, it is actually unable to react to
-changes in three situations:
+## Reference
 
-- adding a key to an object
-- deleting a key from an object
-- modifying an array by setting a new value at a given index
+**observe** An observer can observe multiple values with the `observe` method.
+This method takes an object or an array as its argument and will return a proxy
+(which is mapped to the initial object/array). With this proxy, the observer
+can detect whenever any internal value is changed.
 
-In those situations, we need a way to tell the observer that something happened.
-This can be done by using the `set` and `delete` (only for objects) static
-methods of the `Observer`.
+**Registering a callback** Whenever an observer sees a state change, it will
+call its `notifyCB` method. No additional information is given to the callback.
 
-```javascript
+**deepRevNumber** Each observed value has an internal revision number, which
+is incremented every time the value is observed. Sometimes, it can be useful
+to obtain that number:
+
+```js
 const observer = new owl.Observer();
-const obj = { a: 1 };
-observer.observe(obj);
-obj.b = 2; // won't notify the change
-owl.Observer.set(obj, "b", 2); // will notify the change
+const obj = observer.observe({ a: { b: 1 } });
 
-delete obj.b; // won't notify the change
-owl.Observer.delete(obj, "b"); // will notify the change
+observer.deepRevNumber(obj.a); // 1
+obj.a.b = 2;
+
+observer.deepRevNumber(obj.a); // 2
 ```
 
-```javascript
-const observer = new owl.Observer();
-const arr = ["a"];
-observer.observe(arr);
-arr[0] = "b"; // won't notify the change
-owl.Observer.set(arr, 0, "b"); // will notify the change
-```
+The `deepRevNumber` can also return 0, which indicates that the value is not
+observed.

doc/quick_start.md

@@ -55,29 +55,28 @@ To build an application (or a sub-part of an application), we need two things:
 
 - an environment: it is the global context in which we are working. It needs to
   contain a QWeb instance (preloaded with templates), and anything else that we
-  need. In practice, it could context some user session information, some
+  need. In practice, it could be used to contain some user session information, some
   configuration keys (for example, isMobile = true/false if we are in mobile mode).
 
-- a description of the user interface: there should be a root widget, which can
-  have sub widgets
+- a description of the user interface: there should be a root component, which can
+  have sub components
 
 Here are a few steps that we may take to get started:
 
 - get the templates
 - create a qweb engine, with the templates
 - create an environment
-- create an instance of the root widget
-- mount the root widget to a DOM element
+- create an instance of the root component
+- mount the root component to a DOM element
 
 Let us now add the javascript to make it work, in `app.js`:
 
 ```javascript
+const useState = owl.hooks.useState;
+
 class ClickCounter extends owl.Component {
-  constructor() {
-    super(...arguments);
-    this.template = "clickcounter";
-    this.state = { value: 0 };
-  }
+  static template = "clickcounter";
+  state = useState({ value: 0 });
 
   increment() {
     this.state.value++;
@@ -88,7 +87,7 @@ class ClickCounter extends owl.Component {
 // Application initialization
 //------------------------------------------------------------------------------
 async function start() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
+  const templates = await owl.utils.loadFile("templates.xml");
   const env = {
     qweb: new owl.QWeb(templates)
   };

doc/qweb.md

@@ -20,7 +20,7 @@
 
 ## Overview
 
-[QWeb](https://www.odoo.com/documentation/12.0/reference/qweb.html) is the primary templating engine used by Odoo. It is based on the XML format, and used
+[QWeb](https://www.odoo.com/documentation/13.0/reference/qweb.html) is the primary templating engine used by Odoo. It is based on the XML format, and used
 mostly to generate HTML. In OWL, QWeb templates are compiled into functions that
 generate a virtual dom representation of the HTML.
 
@@ -33,7 +33,7 @@ To avoid element rendering, a placeholder element `<t>` is also available, which
     <span t-if="somecondition">Some string</span>
     <ul t-else="1">
         <li t-foreach="messages" t-as="message">
-            <t t-esc="message">
+            <t t-esc="message"/>
         </li>
     </ul>
 </div>
@@ -44,7 +44,7 @@ with a few interesting points:
 
 - it compiles templates into functions that output a virtual DOM instead of a
   string. This is necessary for the component system.
-- it has a few extra directives: `t-widget`, `t-on`, ...
+- it has a few extra directives: `t-component`, `t-on`, ...
 
 ## Directives
 
@@ -65,16 +65,15 @@ We present here a list of all standard QWeb directives:
 The component system in Owl requires additional directives, to express various
 needs. Here is a list of all Owl specific directives:
 
-| Name                                         | Description                                                                         |
-| -------------------------------------------- | ----------------------------------------------------------------------------------- |
-| `t-widget`, `t-keepalive`, `t-asyncroot` | [Defining a sub component](component.md#composition)                                |
-| `t-ref`                                      | [Setting a reference to a dom node or a sub component](component.md#references)     |
-| `t-key`                                      | [Defining a key (to help virtual dom reconciliation)](component.md#t-key-directive) |
-| `t-on-*`                                     | [Event handling](component.md#event-handling)                                       |
-| `t-transition`                               | [Defining an animation](animations.md#css-transitions)                              |
-| `t-mounted`                                  | [Callback when a node or component is mounted](component.md#t-mounted-directive)    |
-| `t-slot`                                     | [Rendering a slot](component.md#slots)                                              |
-| `t-model`                                    | [Form input bindings](component.md#form-input-bindings)                             |
+| Name                                                   | Description                                                                         |
+| ------------------------------------------------------ | ----------------------------------------------------------------------------------- |
+| `t-component`, `t-props`, `t-keepalive`, `t-asyncroot` | [Defining a sub component](component.md#composition)                                |
+| `t-ref`                                                | [Setting a reference to a dom node or a sub component](component.md#references)     |
+| `t-key`                                                | [Defining a key (to help virtual dom reconciliation)](component.md#t-key-directive) |
+| `t-on-*`                                               | [Event handling](component.md#event-handling)                                       |
+| `t-transition`                                         | [Defining an animation](animations.md#css-transitions)                              |
+| `t-slot`                                               | [Rendering a slot](component.md#slots)                                              |
+| `t-model`                                              | [Form input bindings](component.md#form-input-bindings)                             |
 
 ## QWeb Engine
 
@@ -86,7 +85,7 @@ instantiated:
 const qweb = new owl.QWeb();
 ```
 
-It's API is quite simple:
+Its API is quite simple:
 
 - **`constructor(data)`**: constructor. Takes an optional string to add initial
   templates (see `addTemplates` for more information on format of the string).
@@ -95,12 +94,15 @@ It's API is quite simple:
   const qweb = new owl.QWeb(TEMPLATES);
   ```
 
-- **`addTemplate(name, xmlStr)`**: add a specific template.
+- **`addTemplate(name, xmlStr, allowDuplicate)`**: add a specific template.
 
   ```js
   qweb.addTemplate("mytemplate", "<div>hello</div>");
   ```
 
+  If the optional `allowDuplicate` is set to `true`, then `QWeb` will simply
+  ignore templates added for a second time. Otherwise, `QWeb` will crash.
+
 - **`addTemplates(xmlStr)`**: add a list of templates (identified by `t-name`
   attribute).
 
@@ -108,7 +110,7 @@ It's API is quite simple:
   const TEMPLATES = `
     <templates>
       <div t-name="App" class="main">main</div>
-      <div t-name="OtherWidget">other widget</div>
+      <div t-name="OtherComponent">other component</div>
     </templates>`;
   qweb.addTemplates(TEMPLATES);
   ```
@@ -117,24 +119,45 @@ It's API is quite simple:
   which is a virtual representation of the DOM (see [vdom doc](vdom.md)).
 
   ```js
-  const vnode = qweb.render("App", widget);
+  const vnode = qweb.render("App", component);
   ```
 
-- **`register(name, Component)`**: static function to register an OWL Component
+- **`renderToString(name, context)`**: renders a template, but returns an html
+  string.
+
+  ```js
+  const str = qweb.renderToString("someTemplate", somecontext);
+  ```
+
+- **`registerTemplate(name, template)`**: static function to register a global
+  QWeb template. This is useful for commonly used components accross the
+  application, and for making a template available to an application without
+  having a reference to the actual QWeb instance.
+
+  ```js
+  QWeb.registerTemplate("mytemplate", `<div>some template</div>`);
+  ```
+
+- **`registerComponent(name, Component)`**: static function to register an OWL Component
   to QWeb's global registry. Globally registered Components can be used in
-  templates (see the `t-widget` directive). This is useful for commonly used
+  templates (see the `t-component` directive). This is useful for commonly used
   components accross the application.
 
   ```js
   class Dialog extends owl.Component { ... }
-  QWeb.register("Dialog", Dialog);
+  QWeb.registerComponent("Dialog", Dialog);
 
   ...
 
-  class ParentWidget extends owl.Component { ... }
-  qweb.addTemplate("ParentWidget", "<div><t t-widget='Dialog'/></div>");
+  class ParentComponent extends owl.Component { ... }
+  qweb.addTemplate("ParentComponent", "<div><Dialog/></div>");
   ```
 
+In some way, a `QWeb` instance is the core of an Owl application. It is the only
+mandatory element of an [environment](component.md#environment). As such, it
+has an extra responsibility: it can act as an event bus for internal communication
+between Owl classes. This is the reason why `QWeb` actually extends [EventBus](event_bus.md).
+
 ## Reference
 
 We define in this section the specification of how `QWeb` templates should be
@@ -143,7 +166,7 @@ specific extensions are documented in various other parts of the documentation.
 
 ### White Spaces
 
-White spaces in a templates are handled in a special way:
+White spaces in a template are handled in a special way:
 
 - consecutive whitespaces are always condensed to a single whitespace
 - if a whitespace-only text node contains a linebreak, it is ignored
@@ -179,13 +202,13 @@ root nodes.
 
 QWeb expressions are strings that will be processed at compile time. Each variable in
 the javascript expression will be replaced by a lookup in the context (so, the
-widget). For example, `a + b.c(d)` will be converted into:
+component). For example, `a + b.c(d)` will be converted into:
 
 ```js
 context["a"] + context["b"].c(context["d"]);
 ```
 
-It is useful to explain the various rules that applies on these expressions:
+It is useful to explain the various rules that apply on these expressions:
 
 1. it should be a simple expression which returns a value. It cannot be a statement.
 
@@ -263,6 +286,11 @@ rendered with the value `value` set to `<span>foo</span>` in the rendering conte
 <p><span>foo</span></p>
 ```
 
+Note that since the content of the expression is not known beforehand, the `t-raw`
+directive has to parse the html (and convert it to a virtual dom structure) for
+each rendering. So, it will be much slower than a regular template. It is
+therefore advised to limit the use of `t-raw` whenever possible.
+
 ### Setting Variables
 
 QWeb allows creating variables from within the template, to memoize a computation (to use it multiple times), give a piece of data a clearer name, ...
@@ -362,14 +390,25 @@ If an expression evaluates to a falsy value, it will not be set at all:
 <div t-att-foo="false"/>  <!-- result: <div></div> -->
 ```
 
-There is another way to format a string attribute: the `t-attf-` directive. With
-it, you get string interpolation:
+It is sometimes convenient to format an attribute with string interpolation. In
+that case, the `t-attf-` directive can be used. It is useful when we need to mix
+literal and dynamic elements, such as css classes.
 
 ```xml
 <div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>
 <!-- result if values are set to 1,2 and 3: <div foo="a 0 is 1 of 2 ]"></div> -->
 ```
 
+If we need completely dynamic attribute names, then there is an additional
+directive: `t-att`, which takes either an object (with keys mapping to their
+values) or a pair `[key, value]`. For example:
+
+```xml
+<div t-att="{'a': 1, 'b': 2}"/> <!-- result: <div a="1" b="2"></div> -->
+
+<div t-att="['a', 'b']"/> <!-- <div a="b"></div> -->
+```
+
 ### Loops
 
 QWeb has an iteration directive `t-foreach` which take an expression returning the
@@ -422,16 +461,16 @@ the context of the `t-foreach`, the value is copied at the end of the foreach
 into the global context.
 
 ```xml
-<t t-set="existing_variable" t-value="False"/>
+<t t-set="existing_variable" t-value="false"/>
 <!-- existing_variable now False -->
 
 <p t-foreach="Array(3)" t-as="i">
-    <t t-set="existing_variable" t-value="True"/>
-    <t t-set="new_variable" t-value="True"/>
-    <!-- existing_variable and new_variable now True -->
+    <t t-set="existing_variable" t-value="true"/>
+    <t t-set="new_variable" t-value="true"/>
+    <!-- existing_variable and new_variable now true -->
 </p>
 
-<!-- existing_variable always True -->
+<!-- existing_variable always true -->
 <!-- new_variable undefined -->
 ```
 
@@ -504,4 +543,4 @@ will stop execution if the browser dev tools are open.
 <t t-log="foo"/>
 ```
 
-will print 42 to the console
+will print 42 to the console.

doc/readme.md

@@ -1,13 +1,66 @@
 # 🦉 OWL Documentation 🦉
 
+## Owl Content
+
+Owl is a javascript library that contains some core classes and function to help
+build applications. Here is a complete representation of its content:
+
+```
+owl
+    Component
+    Context
+    QWeb
+    Store
+    useState
+    core
+        EventBus
+        Observer
+    hooks
+        onWillStart
+        onMounted
+        onWillUpdateProps
+        onWillPatch
+        onPatched
+        onWillUnmount
+        useContext
+        useState
+        useRef
+        useSubEnv
+        useStore
+        useDispatch
+        useGetters
+    misc
+        AsyncRoot
+    router
+        Link
+        RouteComponent
+        Router
+    tags
+        xml
+    utils
+        debounce
+        escape
+        loadJS
+        loadFile
+        shallowEqual
+        whenReady
+```
+
+Note that for convenience, the `useState` hook is also exported at the root of the `owl` object.
+
 ## Reference
 
 - [Animations](animations.md)
 - [Component](component.md)
+- [Context](context.md)
 - [Event Bus](event_bus.md)
+- [Hooks](hooks.md)
+- [Misc](misc.md)
 - [Observer](observer.md)
 - [QWeb](qweb.md)
+- [Router](router.md)
 - [Store](store.md)
+- [Tags](tags.md)
 - [Utils](utils.md)
 - [Virtual DOM](vdom.md)
 
@@ -19,3 +72,4 @@
 
 - [Comparison with React/Vue](comparison.md)
 - [Tooling](tooling.md)
+- [Templates to start Owl applications (external link)](https://github.com/ged-odoo/owl-templates)

doc/router.md

@@ -0,0 +1,178 @@
+# 🦉 Router 🦉
+
+## Content
+
+- [Overview](#overview)
+- [Example](#example)
+- [Reference](#reference)
+  - [Route Definition](#route-definition)
+  - [Router](#router)
+  - [Navigation Guards](#navigation-guards)
+  - [RouteComponent](#routecomponent)
+  - [Link](#link)
+
+## Overview
+
+It is often useful to organize an application around urls. If the application is
+a single page application, then we need a way to manage those urls in the browser.
+This is why there are many different routers for different frameworks. A generic
+router can do the job just fine, but a specialized router for Owl can give a
+better developer experience.
+
+The Owl router support the following features:
+
+- `history` or `hash` mode
+- declarative routes
+- route redirection
+- navigation guards
+- parameterized routes
+- a `<Link/>` component
+- a `<RouteComponent/>` component
+
+Note that it is still in early stage of developments, and there are probably
+still some issues.
+
+## Example
+
+To use the Owl router, there are some steps that needs to be done:
+
+- declare some routes
+- create a router
+- add it to the environment
+
+```js
+async function protectRoute({ env, to }) {
+  if (!env.session.authUser) {
+    env.session.setNextRoute(to.name);
+    return { to: "SIGN_IN" };
+  }
+  return true;
+}
+
+export const ROUTES = [
+  { name: "LANDING", path: "/", component: Landing },
+  { name: "TASK", path: "/tasks/{{id}}", component: Task },
+  { name: "SIGN_UP", path: "/signup", component: SignUp },
+  { name: "SIGN_IN", path: "/signin", component: SignIn },
+  { name: "ADMIN", path: "/admin", component: Admin, beforeRouteEnter: protectRoute },
+  { name: "ACCOUNT", path: "/account", component: Account, beforeRouteEnter: protectRoute },
+  { name: "UNKNOWN", path: "*", redirect: { to: "LANDING" } }
+];
+
+function makeEnvironment() {
+    ...
+    const env = { qweb };
+    env.session = new Session(env);
+    env.router = new owl.router.Router(env, ROUTES);
+    await env.router.start();
+    return env;
+}
+```
+
+Notice that the router needs to be started. This is an asynchronous operation
+because it needs to apply the potential navigation guards on the current route
+(which may or may not mean that the application is redirected to another route).
+
+## Reference
+
+### Route definition
+
+A route need to be defined as an object with the following keys:
+
+- `name` (optional): a (unique) string useful to identify the current route. If not
+  given, it will be assigned an automatic name,
+- `path`: a string describing the url. It can be static: `/admin` or dynamic: `/users/{{id}}`.
+  It also can be `*`, to catch all remaining routes.
+- `component` (optional): an Owl component that will be used by the `t-routecomponent`
+  directive if the route is active
+- `redirect` (optional): should be destination object (with optional keys `path`, `to` and `params`) if given, the application will be redirected to the destination whenever we match this route
+- `beforeRouteEnter`: defines a [navigation guard](#navigation-guards).
+
+### `Router`
+
+The `Router` constructor takes three arguments:
+
+- `env`: a valid environment,
+- a list of routes,
+- an optional object (with the only key `mode` which can be `history` (default
+  value) or `hash`).
+
+`history` will use the browser [History API](https://developer.mozilla.org/en-US/docs/Web/API/History_API) as the mechanism to manage URL.\
+Example: `https://yourdomain.tld/my_custom_route`.\
+For this mechanism to work, you need a way to configure your web server accordingly.
+
+`hash` will manipulate the hash of the URL.\
+Example: `https://yourdomain.tld/index.html#/my_custom_route`.
+
+```js
+const ROUTES = [...];
+const router = new owl.router.Router(env, ROUTES, {mode: 'history'});
+```
+
+Note that the route are defined in a list, and the order matters: the router
+tries to find a match by going down the list.
+
+The router needs to be added to the environment in the `router` sub key.
+
+Once a router is created, it needs to be started. This is necessary to initialize
+its current state to the current URL (and also, to potentially apply any
+navigation guards and/or redirecting).
+
+```js
+await router.start();
+```
+
+Once started, the router will keep track of the current url and reflect its
+value in two keys:
+
+- `router.currentRoute`
+- `router.currentParams`
+
+The router also has a `navigate` method, useful to programmatically change the
+application to another state (and the url):
+
+```js
+router.navigate({ to: "USER", params: { id: 51 } });
+```
+
+### Navigation Guards
+
+Navigation guards are very useful to be able to execute some business logic/
+perform some actions or redirect to other routes whenever the application is
+entering a new route. For example, the following guard checks if there is an
+authenticated user, and if it is not the case, redirect to the sign in route.
+
+```js
+async function protectRoute({ env, to }) {
+  if (!env.session.authUser) {
+    env.session.setNextRoute(to.name);
+    return { to: "SIGN_IN" };
+  }
+  return true;
+}
+```
+
+A navigation guard is a function that returns a promise, which either resolves
+to `true` (the navigation is accepted), or to another destination object.
+
+### `RouteComponent`
+
+The `RouteComponent` component directs Owl to render the component associated
+to the currently active route (if any):
+
+```xml
+<div t-name="App">
+    <NavBar />
+    <RouteComponent />
+</div>
+```
+
+### `Link`
+
+The `Link` component is a Owl component which render as a `<a>` tag with any
+content. It will compute the proper href from its props, and allow Owl to
+properly navigate to a given url if clicked on it.
+
+```xml
+<Link to="'HOME'">Home</Link>
+```

doc/store.md

@@ -5,26 +5,30 @@
 - [Overview](#overview)
 - [Example](#example)
 - [Reference](#reference)
-  - [Public API](#public-api)
-  - [Mutations](#mutations)
+  - [Store](#store)
   - [Actions](#actions)
   - [Getters](#getters)
   - [Connecting a Component](#connecting-a-component)
+  - [`useStore`](#usestore)
+  - [`useDispatch`](#usedispatch)
+  - [`useGetters`](#usegetters)
+  - [Semantics](#semantics)
+  - [Good Practices](#good-practices)
 
 ## Overview
 
 Managing the state in an application is not an easy task. In some cases, the
 state of an application can be part of the component tree, in a natural way.
-However, there are situations where some part of the state need to be displayed
+However, there are situations where some parts of the state need to be displayed
 in various parts of the user interface, and then, it is not obvious which
 component should own which part of the state.
 
 Owl's solution to this issue is a centralized store. It is a class that owns
-some state, and let the developer update it in a structured way (through
-mutations and actions). Owl components can then connect to the store, and will
-be updated if necessary.
+some (or all) state, and lets the developer update it in a structured way, with
+`actions`. Owl components can then connect to the store, and will be updated if
+necessary.
 
-Note: Owl's store is inspired by React Redux and VueX.
+Note: Owl store is inspired by React Redux and VueX.
 
 ## Example
 
@@ -32,19 +36,12 @@ Here is what a simple store looks like:
 
 ```js
 const actions = {
-  addTodo({ commit }, message) {
-    commit("addTodo", message);
-  }
-};
-
-const mutations = {
   addTodo({ state }, message) {
-    const todo = {
+    state.todos.push({
       id: state.nextId++,
       message,
       isCompleted: false
-    };
-    state.todos.push(todo);
+    });
   }
 };
 
@@ -53,57 +50,119 @@ const state = {
   nextId: 1
 };
 
-const store = new owl.Store({ state, actions, mutations });
-store.on("update", () => console.log(store.state));
+const store = new owl.Store({ state, actions });
+store.on("update", null, () => console.log(store.state));
 
 // updating the state
 store.dispatch("addTodo", "fix all bugs");
 ```
 
+This example shows how a store can be defined and used. Note that in most cases,
+actions will be dispatched by connected components.
+
 ## Reference
 
-The store is a simple [`owl.EventBus`](event_bus.md) that triggers `update` events whenever its
-state is changed. Note that these events are triggered only after a microtask
-tick, so only one event will be triggered for any number of state changes in a
+### `Store`
+
+The store is a simple [`owl.EventBus`](event_bus.md) that triggers `update` events
+whenever its state is changed. Note that these events are triggered only after a
+microtask tick, so only one event will be triggered for any number of state changes in a
 call stack.
 
 Also, it is important to mention that the state is observed (with an `owl.Observer`),
-which is the reason why it is able to know if it was changed. This implies that
-state changes need to be done carefully in some cases (adding a new key to an
-object, or modifying an array with the `arr[i] = newValue` syntax). See the
+which is the reason why it is able to know if it was changed. See the
 [Observer](observer.md)'s documentation for more details.
 
-### Public API
+The `Store` class is quite small. It has two public methods:
 
-1. `constructor`
-2. `commit`
-3. `dispatch`
+- its constructor
+- `dispatch`
 
-### Mutations
+The constructor takes a configuration object with four (optional) keys:
 
-Mutations are the only way to modify the state. Changing the state outside a
-mutation is not allowed (and should throw an error). Mutations are synchronous.
+- the initial state
+- the actions
+- the getters
+- the environment
+
+```javascript
+const config = {
+  state,
+  actions,
+  getters,
+  env
+};
+const store = new Store(config);
+```
 
 ### Actions
 
-Actions are used to coordinate state changes. It is also useful whenever some
-asynchronous logic is necessary. For example, fetching data should be done
-in an action.
+Actions are used to coordinate state changes. It can be used for both synchronous
+and asynchronous logic.
 
 ```js
 const actions = {
-  async login({ commit }) {
-    commit("setLoginState", "pending");
+  async login({ state }, info) {
+    state.loginState = "pending";
     try {
-      const loginInfo = await doSomeRPC("/login/", "someinfo");
-      commit("setLoginState", loginInfo);
-    } catch {
-      commit("setLoginState", "error");
+      const loginInfo = await doSomeRPC("/login/", info);
+      state.loginState = loginInfo;
+    } catch (e) {
+      state.loginState = "error";
     }
   }
 };
 ```
 
+The first argument to an action method is an object with four keys:
+
+- `state`: the current state of the store content,
+- `dispatch`: a function that can be used to dispatch other actions,
+- `getters`: an object containing all getters defined in the store,
+- `env`: the current environment. This is useful sometimes, in particular if
+  an action needs to apply some side effects (such as performing an rpc), and
+  the `rpc` method is located in the environment.
+
+Actions are called with the `dispatch` method on the store, and can receive an
+arbitrary number of arguments.
+
+```js
+store.dispatch("login", someInfo);
+```
+
+Note that anything returned by an action will also be returned by the `dispatch`
+call.
+
+Also, it is important to be aware that we need to be careful with asynchronous
+logic. Each state change will potentially trigger a rerendering, so we need to
+make sure that we do not have a partially corrupted state. Here is an example that
+is likely not a good idea:
+
+```javascript
+const actions = {
+  async fetchSomeData({ state }, recordId) {
+    state.recordId = recordId;
+    const data = await doSomeRPC("/read/", recordId);
+    state.recordData = data;
+  }
+};
+```
+
+In the previous example, there is a period of time in which the state has a
+`recordId` which does not correspond to the `recordData`. It is more likely that
+we want an atomic update: updating the `recordId` at the same time as the `recordData`
+values:
+
+```javascript
+const actions = {
+  async fetchSomeData({ state }, recordId) {
+    const data = await doSomeRPC("/read/", recordId);
+    state.recordId = recordId;
+    state.recordData = data;
+  }
+};
+```
+
 ### Getters
 
 Usually, data contained in the store will be stored in a normalized way. For
@@ -129,7 +188,7 @@ transform the data contained in the store.
 const getters = {
   getPost({ state }, id) {
     const post = state.posts.find(p => p.id === id);
-    const author = state.authors.find(a => (a.id = post.id));
+    const author = state.authors.find(a => a.id === post.id);
     return {
       id,
       author,
@@ -142,68 +201,122 @@ const getters = {
 const post = store.getters.getPost(id);
 ```
 
-Getters take *at most* one argument.
+Getters take _at most_ one argument.
 
-
-Note that getters are cached if they don't take any argument, or their argument
-is a string or a number.
+Note that getters are not cached.
 
 ### Connecting a Component
 
-By default, an Owl `Component` is not connected to any store. The `connect`
-function is there to create sub Components that are connected versions of
-Components.
+At some point, we need a way to interact with the store from a component. This
+can be done with the help of the three store hooks:
+
+- [`useStore`](#usestore) to subscribe a component to some part of the store state,
+- [`useDispatch`](#usedispatch) to get a reference to a dispatch function,
+- [`useGetters`](#usegetters) to get a reference to the getters defined in the store.
+
+Assume we have this store:
 
 ```javascript
 const actions = {
-  increment({ commit }) {
-    commit("increment", 1);
-  }
-};
-const mutations = {
   increment({ state }, val) {
-    state.counter += val;
+    state.counter.value += val;
   }
 };
+
 const state = {
-  counter: 0
+  counter: { value: 0 }
 };
-const store = new owl.Store({ state, actions, mutations });
+const store = new owl.Store({ state, actions });
+```
 
-class Counter extends owl.Component {
-  increment() {
-    this.env.store.dispatch("increment");
-  }
-}
-function mapStoreToProps(state) {
-  return {
-    value: state.counter
-  };
-}
-const ConnectedCounter = owl.connect(Counter, mapStoreToProps);
+A counter component can then select this value and dispatch an action like this:
 
-const counter = new ConnectedCounter({ store, qweb });
+```js
+class Counter extends Component {
+  counter = useStore(state => state.counter);
+  dispatch = useDispatch();
+}
+
+const counter = new Counter({ store, qweb });
 ```
 
 ```xml
-<button t-name="Counter" t-on-click="increment">
-  Click Me! [<t t-esc="props.value"/>]
+<button t-name="Counter" t-on-click="dispatch('increment')">
+  Click Me! [<t t-esc="counter.value"/>]
 </button>
 ```
 
-The arguments of `connect` are:
+### `useStore`
 
-- `Counter`: an owl `Component` to connect
-- `mapStoreToProps`: a function that extracts the `props` of the Component
-  from the `state` of the `Store` and returns them as a dict
-- `options`: dictionary of optional parameters that may contain
-  - `getStore`: a function that takes the `env` in arguments and returns an
-    instance of `Store` to connect to (if not given, connects to `env.store`)
-  - `hashFunction`: the function to use to detect changes in the state (if not
-    given, generates a function that uses revision numbers, incremented at
-    each state change)
-  - `deep`: [only useful if no hashFunction is given] if false, only watch
-    for top level state changes (true by default)
+The `useStore` hook is used to select some part of the store state. It accepts
+two arguments:
 
-The `connect` function returns a sub class of the given `Component` which is
-connected to the `store`.
+- a selector function, which takes the store state as first argument (and the
+  component props as second argument) and returns
+  an object or an array (which will be then observed),
+- optionally, an object with a `store` key (if we want to override the default
+  store) and an equality function (if we want to specialize the comparison).
+
+If the `useStore` callback selects a sub part of the store state, the component
+will only be rerendered whenever this part of the state changes. Otherwise, it
+will perform a strict equality check and will update the component every time this
+check fails.
+
+### `useDispatch`
+
+The `useDispatch` hook is useful when a component needs to be able to dispatch
+actions. It takes an optional argument, which is a store. If not given, it will
+use the store in the environment.
+
+Note that a component does not need to be connected in any other way to the store.
+For example:
+
+```js
+class DoSomethingButton extends Component {
+  static template = xml`<button t-on-click="dispatch('something')">Click</button>`;
+  dispatch = useDispatch();
+}
+```
+
+### `useGetters`
+
+The `useGetters` hook is useful when a component needs to be able to use the
+getters defined in a store. It takes an optional argument, which is a store. If
+not given, it will use the store in the environment.
+
+Note that a component does not need to be connected in any other way to the store.
+For example:
+
+```js
+class InfoButton extends Component {
+  static template = xml`<span><t t-esc="getters.somevalue()"></span>`;
+  getters = useGetters();
+}
+```
+
+### Semantics
+
+The `Store` class and the `useStore` hook try to be smart and to optimize as much
+as possible the rendering and update process. What is important to know is:
+
+- components are always updated in the order of their creation (so, parent
+  before children),
+- they are updated only if they are in the DOM,
+- if a parent is asynchronous, the system will wait for it to complete its
+  update before updating other components,
+- in general, updates are not coordinated. This is not a problem for synchronous
+  components, but if there are many asynchronous components, this could lead to
+  a situation where some part of the UI is updated and some other part of the UI is
+  not updated.
+
+### Good Practices
+
+- avoid asynchronous components as much as possible. Asynchronous components
+  lead to situations where parts of the UI is not updated immediately,
+- do not be afraid to connect many components, parent or children if needed. For
+  example, a `MessageList` component could get a list of ids in its `useStore`
+  call and a `Message` component could get the data of its own
+  message,
+- since the `useStore` function is called for each connected component,
+  for each state update, it is important to make sure that these functions are
+  as fast as possible.

doc/tags.md

@@ -0,0 +1,47 @@
+# 🦉 Tags 🦉
+
+Tags are very small helpers to make it easy to write inline templates. There is
+only one currently available tag: `xml`, but we plan to add other tags later,
+such as a `css` tag, which will be used to write single file components.
+
+## XML tag
+
+Without tags, creating a standalone component would look like this:
+
+```js
+import { Component } from 'owl'
+
+const name = 'some-unique-name';
+const template = `
+    <div>
+        <span t-if="somecondition">text</span>
+        <button t-on-click="someMethod">Click</button>
+    </div>
+`;
+QWeb.registerTemplate(name, template);
+
+class MyComponent extends Component {
+    static template = name;
+
+    ...
+}
+```
+
+With tags, this process is slightly simplified. The name is uniquely generated,
+and the template is automatically registered:
+
+```js
+import { Component } from 'owl'
+import { xml } from 'owl/tags'
+
+class MyComponent extends Component {
+    static template = xml`
+        <div>
+            <span t-if="somecondition">text</span>
+            <button t-on-click="someMethod">Click</button>
+        </div>
+    `;
+
+    ...
+}
+```

doc/tooling.md

@@ -6,6 +6,7 @@
 - [Development Mode](#development-mode)
 - [Playground](#playground)
 - [Benchmarks](#benchmarks)
+- [Single File Component](#single-file-component)
 
 ## Overview
 
@@ -37,6 +38,9 @@ owl.__info__.mode = "dev";
 Note that templates compiled with the `prod` settings will not be recompiled.
 So, changing this setting is best done at startup.
 
+An important job done by the `dev` mode is to validate props for each component
+creation and update. Also, extra props will cause an error.
+
 ## Playground
 
 The playground is an important application designed to help learning and
@@ -53,3 +57,31 @@ Note: This is more an internal tool, useful for people working on Owl.
 The benchmarks application is a very small application, implemented in different
 frameworks, and in different versions of Owl. This is a simple internal tool,
 useful to compare various performance metrics on some tasks.
+
+## Single File Component
+
+If you want to have `xml` syntax highlighting while using the `xml` helper which
+helps you define inline templates, there is a VS Code addon `Comment tagged template`
+which, if installed, does exactly that. To enable it, you need to add a comment,
+like this:
+
+```js
+// -----------------------------------------------------------------------------
+// TEMPLATE
+// -----------------------------------------------------------------------------
+const TEMPLATE = xml/* xml */ `
+	<div class="main two-columns">
+		<Sidebar/>
+		<Content />
+	</div>`;
+
+// -----------------------------------------------------------------------------
+// CODE
+// -----------------------------------------------------------------------------
+class MyComponent extends Component {
+  static template = TEMPLATE;
+  static components = { Sidebar, Content };
+
+  // rest of component...
+}
+```

doc/utils.md

@@ -7,9 +7,10 @@ functions are all available in the `owl.utils` namespace.
 
 - [`whenReady`](#whenready): executing code when DOM is ready
 - [`loadJS`](#loadjs): loading script files
-- [`loadTemplates`](#loadtemplates): loading xml files
+- [`loadFile`](#loadfile): loading a file (useful for templates)
 - [`escape`](#escape): sanitizing strings
 - [`debounce`](#debounce): limiting rate of function calls
+- [`shallowEqual`](#shallowequal): shallow object comparison
 
 ## `whenReady`
 
@@ -18,15 +19,15 @@ not ready yet, resolved directly otherwise). If called with a callback as
 argument, it executes it as soon as the DOM ready (or directly).
 
 ```js
-Promise.all([loadTemplates(), owl.utils.whenReady()]).then(function([
-  templates
-]) {
+Promise.all([loadFile("templates.xml"), owl.utils.whenReady()]).then(function([templates]) {
   const qweb = new owl.QWeb(templates);
   const app = new App({ qweb });
   app.mount(document.body);
 });
 ```
 
+or alternatively:
+
 ```js
 owl.utils.whenReady(function() {
   const qweb = new owl.QWeb();
@@ -37,10 +38,12 @@ owl.utils.whenReady(function() {
 
 ## `loadJS`
 
-`loadJS` takes a url (string) for a javascript resource, and loads it. It returns
-a promise, so the caller can properly react when it is ready. Also, it is smart:
-it maintains a list of urls previously loaded (or currently being loaded), and
-prevent doing twice the work.
+`loadJS` takes a url (string) for a javascript resource, and loads it (by adding
+a script tag in the document head). It returns a promise, so the caller can
+properly reacts when it is ready. Also, it is smart: it maintains a list of urls
+previously loaded (or currently being loaded), and prevent doing twice the work.
+
+For example, it is useful for lazy loading external libraries:
 
 ```js
 class MyComponent extends owl.Component {
@@ -50,16 +53,96 @@ class MyComponent extends owl.Component {
 }
 ```
 
-## `loadTemplates`
+## `loadFile`
+
+`loadFile` is a helper function to fetch a file. It simply
+performs a `GET` request and returns the resulting string in a promise. The
+initial usecase for this function is to load a template file. For example:
 
 ```js
 async function makeEnv() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
+  const templates = await owl.utils.loadFile("templates.xml");
   const qweb = new owl.QWeb(templates);
   return { qweb };
 }
 ```
 
+Note that unlike `loadJS`, this function returns the content of the file as a
+string. It does not add a `script` tag or any other side effect.
+
 ## `escape`
 
+Sometimes, we need to display dynamic data (for example user-generated data) in
+the user interface. If this is done by a `QWeb` template, it is not an issue:
+
+```xml
+    <div><t t-esc="user.data"/></div>
+```
+
+The `QWeb` engine will create a `div` node and add the content of the `user.data`
+string as a text node, so the web browser will not parse it as html. However,
+it may be a problem if this is done with some javascript code like this:
+
+```js
+class BadComponent extends Component {
+  // some template with a ref to a div
+  // some code ...
+
+  mounted() {
+    this.divRef.el.innerHTML = this.state.value;
+  }
+}
+```
+
+In this case, the content of the `div` will be parsed as html, which may inject
+unwanted behaviour. To fix this, the `escape` function will simply transform a
+string into an escaped version of the same string, which will be properly displayed
+by the browser, but which will not be parsed as html (for example, `"<ok>"` is
+escaped to the string: `"&lt;ok&gt;"`). So, the bad example above can be fixed
+with the following change:
+
+```js
+this.divRef.el.innerHTML = owl.utils.escape(this.state.value);
+```
+
 ## `debounce`
+
+The `debounce` function is useful when we want to limit the number of times some
+function/action is perfomed. For example, this may be useful to prevent issue
+with people double clicking on a button.
+
+It takes three arguments:
+
+- `func` (function): this is the function that will be rate limited
+- `wait` (number): this is the number of milliseconds that we want to use to
+  rate limit the function `func`
+- `immediate` (optional, boolean, default=false): if `immediate` is true, the
+  function will be triggered immediately (leading edge of the interval). If false,
+  the function will be triggered at the end (trailing edge).
+
+It returns a function. For example:
+
+```js
+const debounce = owl.utils.debounce;
+window.addEventListener("mousemove", debounce(doSomething, 100));
+```
+
+As this example shows, it is usualy useful for event handlers which are triggered
+very quickly, such as `scroll` or `mousemove` events.
+
+## `shallowEqual`
+
+This function checks if two objects have the same values assigned to each keys:
+
+```js
+shallowEqual({ a: 1, b: 2 }, { a: 1, b: 2 }); // true
+shallowEqual({ a: 1, b: 2 }, { a: 1, b: 3 }); // false
+```
+
+However, for performance reasons, it assumes that the two objects have the same
+keys. If we are in a situation where this is not guaranteed, the following code
+will work:
+
+```js
+const completeShallowEqual = (a, b) => shallowEqual(a, b) && shallowEqual(b, a);
+```

package.json

@@ -1,35 +1,39 @@
 {
-  "name": "owl",
-  "version": "0.15.0",
+  "name": "owl-framework",
+  "version": "0.24.0",
   "description": "Odoo Web Library (OWL)",
   "main": "src/index.ts",
   "scripts": {
     "build:js": "tsc --target esnext --module es6 --outDir dist/owl",
     "build:bundle": "rollup -c",
     "build": "npm run build:js && npm run build:bundle",
+    "buildcommonjs": "npm run build:js && npm run build:bundle -- -f cjs",
     "minify": "uglifyjs dist/owl.js -o dist/owl.min.js --compress --mangle",
     "test": "jest",
     "test:watch": "jest --watch",
     "tools:serve": "python3 tools/server.py || python tools/server.py",
     "tools": "npm run build && npm run tools:serve",
     "pretools:watch": "npm run build",
-    "tools:watch": "npm-run-all  --parallel tools:serve \"build:* -- --watch\""
+    "tools:watch": "npm-run-all  --parallel tools:serve \"build:* -- --watch\"",
+    "prettier": "prettier {src/**/*.ts,tests/**/*.ts,doc/**/*.md} --write"
   },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/odoo/owl.git"
   },
   "author": "Odoo",
-  "license": "GPL-3.0-or-later",
+  "license": "LGPL",
   "bugs": {
     "url": "https://github.com/odoo/owl/issues"
   },
   "homepage": "https://github.com/odoo/owl#readme",
+  "dependencies": {},
   "devDependencies": {
     "@types/jest": "^23.3.12",
     "cpx": "^1.5.0",
     "git-rev-sync": "^1.12.0",
     "jest": "^23.6.0",
+    "jest-environment-jsdom": "^24.7.1",
     "live-server": "^1.2.1",
     "npm-run-all": "^4.1.5",
     "rollup": "^1.6.0",
@@ -38,10 +42,8 @@
     "source-map-support": "^0.5.10",
     "ts-jest": "^23.10.5",
     "typescript": "^3.2.2",
-    "uglify-es": "^3.3.9",
-    "jest-environment-jsdom": "^24.7.1"
+    "uglify-es": "^3.3.9"
   },
-  "dependencies": {},
   "jest": {
     "roots": [
       "<rootDir>/src",
@@ -60,5 +62,8 @@
       "json",
       "node"
     ]
+  },
+  "prettier": {
+    "printWidth": 100
   }
 }

roadmap.md

@@ -0,0 +1,46 @@
+# 🦉 OWL Roadmap 🦉
+
+- Current version: 0.24.0
+- Status: mostly stable
+
+This roadmap is only an attempt at predicting Owl's future.  Everything may
+change!
+
+### October 2019
+
+We plan to complete the following tasks:
+
+- improve API for root widgets (issue #306),
+- replace `t-keepalive`, and maybe `t-transition` by components (issue #295).
+
+### November 2019
+
+Once the previous tasks are done, release version 1.0alpha. This means that the
+API should be stable.  But it could change a little bit if we need it for our
+work on Odoo.
+
+### End of 2019
+
+Release v1.0
+
+- API should be stable,
+- we will use semantic versioning,
+- we will maintain a changelog and an upgrade guide.
+
+### 1.x
+
+- add chrome and firefox devtools,
+- add support for single file components,
+- fix every bugs,
+- improve documentation,
+- small backward compatible improvements.
+
+### 2.x (2021? 2022?)
+
+Maybe:
+
+- reimplement vdom to use *block* system, like Vue 3,
+- refactor `QWeb` to use an intermediate representation (some kind of AST) to
+  allow additional optimisations.
+
+

src/component.ts

@@ -1,666 +0,0 @@
-import { Observer } from "./observer";
-import { QWeb, CompiledTemplate } from "./qweb_core";
-import { h, patch, VNode } from "./vdom";
-
-/**
- * Owl Component System
- *
- * This file introduces a declarative and composable component system. It
- * contains:
- *
- * - the Env interface (generic type for the environment)
- * - the Meta interface (the owl specific metadata attached to a component)
- * - the Component class
- */
-
-//------------------------------------------------------------------------------
-// Types/helpers
-//------------------------------------------------------------------------------
-
-/**
- * An Env (environment) is an object that will be (mostly) shared between all
- * components of an Owl application.  It is the location which should contain
- * the qweb instance necessary to render all components.
- *
- * Note that it is totally fine to extend the environment with application
- * specific keys/objects/whatever.  For example, a key `isMobile` (to declare
- * if we are in "mobile" mode), or a shared bus could be useful.
- */
-export interface Env {
-  qweb: QWeb;
-}
-
-/**
- * This is mostly an internal detail of implementation. The Meta interface is
- * useful to typecheck and describe the internal keys used by Owl to manage the
- * component tree.
- */
-export interface Meta<T extends Env, Props> {
-  readonly id: number;
-  vnode: VNode | null;
-  isMounted: boolean;
-  isDestroyed: boolean;
-  parent: Component<T, any, any> | null;
-  children: { [key: number]: Component<T, any, any> };
-  // children mapping: from templateID to widgetID
-  // should it be a map number => Widget?
-  cmap: { [key: number]: number };
-
-  renderId: number;
-  renderProps: Props | null;
-  renderPromise: Promise<VNode> | null;
-  boundHandlers: { [key: number]: any };
-  observer?: Observer;
-  render?: CompiledTemplate;
-  mountedHandlers: { [key: number]: Function };
-}
-
-// If a component does not define explicitely a template
-// key, it needs to find a template with its name (or a parent's).  This is
-// qweb dependant, so we need a place to store this information indexed by
-// qweb instances.
-const TEMPLATE_MAP: { [key: number]: { [name: string]: string } } = {};
-
-//------------------------------------------------------------------------------
-// Widget
-//------------------------------------------------------------------------------
-let nextId = 1;
-
-export class Component<T extends Env, Props extends {}, State extends {}> {
-  readonly __owl__: Meta<Env, Props>;
-  template?: string;
-
-  /**
-   * The `el` is the root element of the widget.  Note that it could be null:
-   * this is the case if the widget is not mounted yet, or is destroyed.
-   */
-  get el(): HTMLElement | null {
-    return this.__owl__.vnode ? (<any>this).__owl__.vnode.elm : null;
-  }
-
-  env: T;
-  state?: State;
-  props: Props;
-
-  // type of props is not easily representable in typescript...
-  static props?: any;
-  static defaultProps?: any;
-
-  refs: {
-    [key: string]: Component<T, any, any> | HTMLElement | undefined;
-  } = {};
-
-  //--------------------------------------------------------------------------
-  // Lifecycle
-  //--------------------------------------------------------------------------
-
-  /**
-   * Creates an instance of Component.
-   *
-   * The root widget of a component tree needs an environment:
-   *
-   * ```javascript
-   *   const root = new RootWidget(env, props);
-   * ```
-   *
-   * Every other widget simply needs a reference to its parent:
-   *
-   * ```javascript
-   *   const child = new SomeWidget(parent, props);
-   * ```
-   *
-   * Note that most of the time, only the root widget needs to be created by
-   * hand.  Other widgets should be created automatically by the framework (with
-   * the t-widget directive in a template)
-   */
-  constructor(parent: Component<T, any, any> | T, props?: Props) {
-    const defaultProps = (<any>this.constructor).defaultProps;
-    if (defaultProps) {
-      props = this._applyDefaultProps(props, defaultProps);
-    }
-    if (QWeb.dev) {
-      this._validateProps(props || {});
-    }
-    // is this a good idea?
-    //   Pro: if props is empty, we can create easily a widget
-    //   Con: this is not really safe
-    //   Pro: but creating widget (by a template) is always unsafe anyway
-    this.props = <Props>props || <Props>{};
-    let id: number = nextId++;
-    let p: Component<T, any, any> | null = null;
-    if (parent instanceof Component) {
-      p = parent;
-      this.env = parent.env;
-      parent.__owl__.children[id] = this;
-    } else {
-      this.env = parent;
-    }
-    this.__owl__ = {
-      id: id,
-      vnode: null,
-      isMounted: false,
-      isDestroyed: false,
-      parent: p,
-      children: {},
-      cmap: {},
-      renderId: 1,
-      renderPromise: null,
-      renderProps: props || null,
-      boundHandlers: {},
-      mountedHandlers: {}
-    };
-  }
-
-  /**
-   * willStart is an asynchronous hook that can be implemented to perform some
-   * action before the initial rendering of a component.
-   *
-   * It will be called exactly once before the initial rendering. It is useful
-   * in some cases, for example, to load external assets (such as a JS library)
-   * before the widget is rendered.
-   *
-   * Note that a slow willStart method will slow down the rendering of the user
-   * interface.  Therefore, some effort should be made to make this method as
-   * fast as possible.
-   *
-   * Note: this method should not be called manually.
-   */
-  async willStart() {}
-
-  /**
-   * mounted is a hook that is called each time a component is attached to the
-   * DOM. This is a good place to add some listeners, or to interact with the
-   * DOM, if the component needs to perform some measure for example.
-   *
-   * Note: this method should not be called manually.
-   *
-   * @see willUnmount
-   */
-  mounted() {}
-
-  /**
-   * The willUpdateProps is an asynchronous hook, called just before new props
-   * are set. This is useful if the component needs some asynchronous task
-   * performed, depending on the props (for example, assuming that the props are
-   * some record Id, fetching the record data).
-   *
-   * This hook is not called during the first render (but willStart is called
-   * and performs a similar job).
-   */
-  async willUpdateProps(nextProps: Props) {}
-
-  /**
-   * The willPatch hook is called just before the DOM patching process starts.
-   * It is not called on the initial render.  This is useful to get some
-   * information which are in the DOM.  For example, the current position of the
-   * scrollbar
-   *
-   * The return value of willPatch will be given to the patched function.
-   */
-  willPatch(): any {}
-
-  /**
-   * This hook is called whenever a component did actually update its props,
-   * state or env.
-   *
-   * This method is not called on the initial render. It is useful to interact
-   * with the DOM (for example, through an external library) whenever the
-   * component was updated.
-   *
-   * Updating the widget state in this hook is possible, but not encouraged.
-   * One need to be careful, because updates here will cause rerender, which in
-   * turn will cause other calls to updated. So, we need to be particularly
-   * careful at avoiding endless cycles.
-   *
-   * The snapshot parameter is the result of the call to willPatch.
-   */
-  patched(snapshot: any) {}
-
-  /**
-   * willUnmount is a hook that is called each time just before a component is
-   * unmounted from the DOM. This is a good place to remove some listeners, for
-   * example.
-   *
-   * Note: this method should not be called manually.
-   *
-   * @see mounted
-   */
-  willUnmount() {}
-
-  //--------------------------------------------------------------------------
-  // Public
-  //--------------------------------------------------------------------------
-
-  /**
-   * Mount the component to a target element.
-   *
-   * This should only be done if the component was created manually. Components
-   * created declaratively in templates are managed by the Owl system.
-   */
-  async mount(target: HTMLElement): Promise<void> {
-    const vnode = await this._prepare();
-    if (this.__owl__.isDestroyed) {
-      // component was destroyed before we get here...
-      return;
-    }
-    this._patch(vnode);
-    target.appendChild(this.el!);
-
-    if (document.body.contains(target)) {
-      this._callMounted();
-    }
-  }
-
-  unmount() {
-    if (this.__owl__.isMounted) {
-      this._callWillUnmount();
-      this.el!.remove();
-    }
-  }
-
-  async render(force: boolean = false, patchQueue?: any[]): Promise<void> {
-    const __owl__ = this.__owl__;
-    if (!__owl__.isMounted) {
-      return;
-    }
-    const shouldPatch: boolean = !patchQueue;
-    if (shouldPatch) {
-      patchQueue = [];
-    }
-    const renderVDom = this._render(force, patchQueue);
-    const renderId = __owl__.renderId;
-    await renderVDom;
-
-    if (shouldPatch && __owl__.isMounted && renderId === __owl__.renderId) {
-      // we only update the vnode and the actual DOM if no other rendering
-      // occurred between now and when the render method was initially called.
-      this._applyPatchQueue(<any[]>patchQueue);
-    }
-  }
-
-  /**
-   * Destroy the component.  This operation is quite complex:
-   *  - it recursively destroy all children
-   *  - call the willUnmount hooks if necessary
-   *  - remove the dom node from the dom
-   *
-   * This should only be called manually if you created the widget.  Most widgets
-   * will be automatically destroyed.
-   */
-  destroy() {
-    const __owl__ = this.__owl__;
-    if (!__owl__.isDestroyed) {
-      const el = this.el;
-      this._destroy(__owl__.parent);
-      if (el) {
-        el.remove();
-      }
-    }
-  }
-
-  /**
-   * This method is called by the component system whenever its props are
-   * updated. If it returns true, then the component will be rendered.
-   * Otherwise, it will skip the rendering (also, its props will not be updated)
-   */
-  shouldUpdate(nextProps: Props): boolean {
-    return true;
-  }
-
-  /**
-   * This method is the correct way to update the environment of a widget. Doing
-   * this will cause a full rerender of the widget and its children, so this is
-   * an operation that should not be done frequently.
-   *
-   * A good usecase for updating the environment would be to update some mostly
-   * static config keys, such as a boolean to determine if we are in mobile
-   * mode or not.
-   */
-  async updateEnv(nextEnv: Partial<T>): Promise<void> {
-    const __owl__ = this.__owl__;
-    if (__owl__.parent && __owl__.parent.env === this.env) {
-      this.env = Object.create(this.env);
-    }
-    Object.assign(this.env, nextEnv);
-    if (__owl__.isMounted) {
-      await this.render(true);
-    }
-  }
-
-  /**
-   * Emit a custom event of type 'eventType' with the given 'payload' on the
-   * component's el, if it exists. However, note that the event will only bubble
-   * up to the parent DOM nodes. Thus, it must be called between mounted() and
-   * willUnmount().
-   */
-  trigger(eventType: string, payload?: any) {
-    if (this.el) {
-      const ev = new CustomEvent(eventType, {
-        bubbles: true,
-        cancelable: true,
-        detail: payload
-      });
-      this.el.dispatchEvent(ev);
-    }
-  }
-
-  //--------------------------------------------------------------------------
-  // Private
-  //--------------------------------------------------------------------------
-
-  _destroy(parent: Component<any, any, any> | null) {
-    const __owl__ = this.__owl__;
-    const isMounted = __owl__.isMounted;
-    if (isMounted) {
-      this.willUnmount();
-      __owl__.isMounted = false;
-    }
-    const children = __owl__.children;
-    for (let key in children) {
-      children[key]._destroy(this);
-    }
-    if (parent) {
-      let id = __owl__.id;
-      delete parent.__owl__.children[id];
-      __owl__.parent = null;
-    }
-    __owl__.isDestroyed = true;
-    delete __owl__.vnode;
-  }
-
-  _callMounted() {
-    const __owl__ = this.__owl__;
-    const children = __owl__.children;
-    for (let id in children) {
-      const comp = children[id];
-      if (!comp.__owl__.isMounted && this.el!.contains(comp.el)) {
-        comp._callMounted();
-      }
-    }
-    __owl__.isMounted = true;
-    const handlers = __owl__.mountedHandlers;
-    for (let key in handlers) {
-      handlers[key]();
-    }
-    this.mounted();
-  }
-
-  _callWillUnmount() {
-    this.willUnmount();
-    const __owl__ = this.__owl__;
-    __owl__.isMounted = false;
-    const children = __owl__.children;
-    for (let id in children) {
-      const comp = children[id];
-      if (comp.__owl__.isMounted) {
-        comp._callWillUnmount();
-      }
-    }
-  }
-
-  async _updateProps(
-    nextProps: Props,
-    forceUpdate: boolean = false,
-    patchQueue?: any[]
-  ): Promise<void> {
-    const shouldUpdate = forceUpdate || this.shouldUpdate(nextProps);
-    if (shouldUpdate) {
-      const defaultProps = (<any>this.constructor).defaultProps;
-      if (defaultProps) {
-        nextProps = this._applyDefaultProps(nextProps, defaultProps);
-      }
-      if (QWeb.dev) {
-        this._validateProps(nextProps);
-      }
-      await this.willUpdateProps(nextProps);
-      this.props = nextProps;
-      await this.render(forceUpdate, patchQueue);
-    }
-  }
-
-  _patch(vnode) {
-    const __owl__ = this.__owl__;
-    __owl__.renderPromise = null;
-    const target = __owl__.vnode || document.createElement(vnode.sel!);
-    __owl__.vnode = patch(target, vnode);
-  }
-  _prepare(): Promise<VNode> {
-    const __owl__ = this.__owl__;
-    __owl__.renderProps = this.props;
-    __owl__.renderPromise = this._prepareAndRender();
-    return __owl__.renderPromise;
-  }
-
-  async _prepareAndRender(): Promise<VNode> {
-    await this.willStart();
-    const __owl__ = this.__owl__;
-    if (__owl__.isDestroyed) {
-      return Promise.resolve(h("div"));
-    }
-    const qweb = this.env.qweb;
-    if (!this.template) {
-      let tmap = TEMPLATE_MAP[qweb.id];
-      if (!tmap) {
-        tmap = {};
-        TEMPLATE_MAP[qweb.id] = tmap;
-      }
-      let p = (<any>this).constructor;
-      let name: string = p.name;
-      let template = tmap[name];
-      if (template) {
-        this.template = template;
-      } else {
-        while (
-          (template = p.name) &&
-          !(template in qweb.templates) &&
-          p !== Component
-        ) {
-          p = p.__proto__;
-        }
-        if (p === Component) {
-          throw new Error(
-            `Could not find template for component "${this.constructor.name}"`
-          );
-        } else {
-          tmap[name] = template;
-          this.template = template;
-        }
-      }
-    }
-    __owl__.render = qweb.render.bind(qweb, this.template);
-    this._observeState();
-    return this._render();
-  }
-
-  async _render(
-    force: boolean = false,
-    patchQueue: any[] = []
-  ): Promise<VNode> {
-    const __owl__ = this.__owl__;
-    __owl__.renderId++;
-    const promises: Promise<void>[] = [];
-    const patch: any[] = [this];
-    if (__owl__.isMounted) {
-      patchQueue.push(patch);
-    }
-    if (__owl__.observer) {
-      __owl__.observer.allowMutations = false;
-    }
-    let vnode = __owl__.render!(this, {
-      promises,
-      handlers: __owl__.boundHandlers,
-      mountedHandlers: __owl__.mountedHandlers,
-      forceUpdate: force,
-      patchQueue
-    });
-    patch.push(vnode);
-    if (__owl__.observer) {
-      __owl__.observer.allowMutations = true;
-    }
-
-    // this part is critical for the patching process to be done correctly. The
-    // tricky part is that a child widget can be rerendered on its own, which
-    // will update its own vnode representation without the knowledge of the
-    // parent widget.  With this, we make sure that the parent widget will be
-    // able to patch itself properly after
-    vnode.key = __owl__.id;
-    __owl__.renderProps = this.props;
-    __owl__.renderPromise = Promise.all(promises).then(() => vnode);
-    return __owl__.renderPromise;
-  }
-
-  /**
-   * Only called by qweb t-widget directive
-   */
-  _mount(vnode: VNode, elm: HTMLElement): VNode {
-    const __owl__ = this.__owl__;
-    __owl__.vnode = patch(elm, vnode);
-    if (__owl__.parent!.__owl__.isMounted && !__owl__.isMounted) {
-      this._callMounted();
-    }
-    return __owl__.vnode;
-  }
-
-  /**
-   * Only called by qweb t-widget directive (when t-keepalive is set)
-   */
-  _remount() {
-    const __owl__ = this.__owl__;
-    if (!__owl__.isMounted) {
-      __owl__.isMounted = true;
-      this.mounted();
-    }
-  }
-
-  _observeState() {
-    if (this.state) {
-      const __owl__ = this.__owl__;
-      __owl__.observer = new Observer();
-      __owl__.observer.observe(this.state);
-      __owl__.observer.notifyCB = this.render.bind(this);
-    }
-  }
-
-  /**
-   * Apply default props (only top level).
-   *
-   * Note that this method does not modify in place the props, it returns a new
-   * prop object
-   */
-  _applyDefaultProps(props: Object | undefined, defaultProps: Object): Props {
-    props = props ? Object.create(props) : {};
-    for (let propName in defaultProps) {
-      if (props![propName] === undefined) {
-        props![propName] = defaultProps[propName];
-      }
-    }
-    return <Props>props;
-  }
-
-  /**
-   * Apply the given patch queue. A patch is a pair [c, vn], where c is a
-   * Component instance and vn a VNode.
-   *   1) Call 'willPatch' on the component of each patch
-   *   2) Call '_patch' on the component of each patch
-   *   3) Call 'patched' on the component of each patch, in inverse order
-   */
-  _applyPatchQueue(patchQueue: any[]) {
-    const patchLen = patchQueue.length;
-    for (let i = 0; i < patchLen; i++) {
-      const patch = patchQueue[i];
-      patch.push(patch[0].willPatch());
-    }
-    for (let i = 0; i < patchLen; i++) {
-      const patch = patchQueue[i];
-      patch[0]._patch(patch[1]);
-    }
-    for (let i = patchLen - 1; i >= 0; i--) {
-      const patch = patchQueue[i];
-      patch[0].patched(patch[2]);
-    }
-  }
-
-  /**
-   * Validate the component props (or next props) against the (static) props
-   * description.  This is potentially an expensive operation: it may needs to
-   * visit recursively the props and all the children to check if they are valid.
-   * This is why it is only done in 'dev' mode.
-   */
-  _validateProps(props: Object) {
-    const propsDef = (<any>this.constructor).props;
-    if (propsDef instanceof Array) {
-      // list of strings (prop names)
-      for (let i = 0, l = propsDef.length; i < l; i++) {
-        if (!(propsDef[i] in props)) {
-          throw new Error(
-            `Missing props '${propsDef[i]}' (widget '${this.constructor.name}')`
-          );
-        }
-      }
-    } else if (propsDef) {
-      // propsDef is an object now
-      for (let propName in propsDef) {
-        if (!(propName in props)) {
-          if (propsDef[propName] && !propsDef[propName].optional) {
-            throw new Error(
-              `Missing props '${propName}' (widget '${this.constructor.name}')`
-            );
-          } else {
-            break;
-          }
-        }
-        let isValid = isValidProp(props[propName], propsDef[propName]);
-        if (!isValid) {
-          throw new Error(
-            `Props '${propName}' of invalid type in widget '${
-              this.constructor.name
-            }'`
-          );
-        }
-      }
-    }
-  }
-}
-
-//------------------------------------------------------------------------------
-// Prop validation helper
-//------------------------------------------------------------------------------
-
-/**
- * Check if an invidual prop value matches its (static) prop definition
- */
-function isValidProp(prop, propDef): boolean {
-  if (typeof propDef === "function") {
-    // Check if a value is constructed by some Constructor.  Note that there is a
-    // slight abuse of language: we want to consider primitive values as well.
-    //
-    // So, even though 1 is not an instance of Number, we want to consider that
-    // it is valid.
-    if (typeof prop === "object") {
-      return prop instanceof propDef;
-    }
-    return typeof prop === propDef.name.toLowerCase();
-  } else if (propDef instanceof Array) {
-    // If this code is executed, this means that we want to check if a prop
-    // matches at least one of its descriptor.
-    let result = false;
-    for (let i = 0, iLen = propDef.length; i < iLen; i++) {
-      result = result || isValidProp(prop, propDef[i]);
-    }
-    return result;
-  }
-  // propsDef is an object
-  let result = isValidProp(prop, propDef.type);
-  if (propDef.type === Array) {
-    for (let i = 0, iLen = prop.length; i < iLen; i++) {
-      result = result && isValidProp(prop[i], propDef.element);
-    }
-  }
-  if (propDef.type === Object) {
-    const shape = propDef.shape;
-    for (let key in shape) {
-      result = result && isValidProp(prop[key], shape[key]);
-    }
-  }
-  return result;
-}

src/component/component.ts

@@ -0,0 +1,688 @@
+import { Observer } from "../core/observer";
+import { CompiledTemplate, QWeb } from "../qweb/index";
+import { h, patch, VNode } from "../vdom/index";
+import "./directive";
+import { Fiber } from "./fiber";
+import "./props_validation";
+import { Scheduler } from "./scheduler";
+
+/**
+ * Owl Component System
+ *
+ * This file introduces a declarative and composable component system. It
+ * contains:
+ *
+ * - the Env interface (generic type for the environment)
+ * - the Internal interface (the owl specific metadata attached to a component)
+ * - the Component class
+ */
+
+//------------------------------------------------------------------------------
+// Types/helpers
+//------------------------------------------------------------------------------
+const raf = window.requestAnimationFrame.bind(window);
+export const scheduler = new Scheduler(raf);
+
+/**
+ * An Env (environment) is an object that will be (mostly) shared between all
+ * components of an Owl application.  It is the location which should contain
+ * the qweb instance necessary to render all components.
+ *
+ * Note that it is totally fine to extend the environment with application
+ * specific keys/objects/whatever.  For example, a key `isMobile` (to declare
+ * if we are in "mobile" mode), or a shared bus could be useful.
+ */
+export interface Env {
+  qweb: QWeb;
+  [key: string]: any;
+}
+
+/**
+ * This is mostly an internal detail of implementation. The Meta interface is
+ * useful to typecheck and describe the internal keys used by Owl to manage the
+ * component tree.
+ */
+interface Internal<T extends Env, Props> {
+  // each component has a unique id, useful mostly to handle parent/child
+  // relationships
+  readonly id: number;
+  vnode: VNode | null;
+  pvnode: VNode | null;
+  isMounted: boolean;
+  isDestroyed: boolean;
+
+  // parent and children keys are obviously useful to setup the parent-children
+  // relationship.
+  parent: Component<T, any> | null;
+  children: { [key: number]: Component<T, any> };
+  // children mapping: from templateID to componentID. templateID identifies a
+  // place in a template. The t-component directive needs it to be able to get
+  // the component instance back whenever the template is rerendered.
+  cmap: { [key: number]: number };
+
+  currentFiber: Fiber | null;
+
+  boundHandlers: { [key: number]: any };
+  observer: Observer | null;
+  renderFn: CompiledTemplate;
+  mountedCB: Function | null;
+  willUnmountCB: Function | null;
+  willPatchCB: Function | null;
+  patchedCB: Function | null;
+  willStartCB: Function | null;
+  willUpdatePropsCB: Function | null;
+  classObj: { [key: string]: boolean } | null;
+  refs: { [key: string]: Component<T, any> | HTMLElement | undefined } | null;
+}
+
+//------------------------------------------------------------------------------
+// Component
+//------------------------------------------------------------------------------
+let nextId = 1;
+
+export class Component<T extends Env, Props extends {}> {
+  readonly __owl__: Internal<Env, Props>;
+  static template?: string | null = null;
+  static _template?: string | null = null;
+  static current: Component<any, any> | null = null;
+  static components = {};
+  static props?: any;
+  static defaultProps?: any;
+
+  /**
+   * The `el` is the root element of the component.  Note that it could be null:
+   * this is the case if the component is not mounted yet, or is destroyed.
+   */
+  get el(): HTMLElement | null {
+    return this.__owl__.vnode ? (<any>this).__owl__.vnode.elm : null;
+  }
+
+  env: T;
+  props: Props;
+
+  //--------------------------------------------------------------------------
+  // Lifecycle
+  //--------------------------------------------------------------------------
+
+  /**
+   * Creates an instance of Component.
+   *
+   * The root component of a component tree needs an environment:
+   *
+   * ```javascript
+   *   const root = new RootComponent(env, props);
+   * ```
+   *
+   * Every other component simply needs a reference to its parent:
+   *
+   * ```javascript
+   *   const child = new SomeComponent(parent, props);
+   * ```
+   *
+   * Note that most of the time, only the root component needs to be created by
+   * hand.  Other components should be created automatically by the framework (with
+   * the t-component directive in a template)
+   */
+  constructor(parent: Component<T, any> | T, props?: Props) {
+    const defaultProps = (<any>this.constructor).defaultProps;
+    Component.current = this;
+    if (defaultProps) {
+      props = this.__applyDefaultProps(props, defaultProps);
+    }
+    // is this a good idea?
+    //   Pro: if props is empty, we can create easily a component
+    //   Con: this is not really safe
+    //   Pro: but creating component (by a template) is always unsafe anyway
+    this.props = <Props>props || <Props>{};
+    let id: number = nextId++;
+    let p: Component<T, any> | null = null;
+    if (parent instanceof Component) {
+      p = parent;
+      this.env = parent.env;
+      parent.__owl__.children[id] = this;
+    } else {
+      this.env = parent;
+      if (QWeb.dev) {
+        // we only validate props for root widgets here.  "Regular" widget
+        // props are validated by the t-component directive
+        QWeb.utils.validateProps(this.constructor, this.props);
+      }
+      this.env.qweb.on("update", this, () => {
+        if (this.__owl__.isMounted) {
+          this.render(true);
+        }
+        if (this.__owl__.isDestroyed) {
+          // this is unlikely to happen, but if a root widget is destroyed,
+          // we want to remove our subscription.  The usual way to do that
+          // would be to perform some check in the destroy method, but since
+          // it is very performance sensitive, and since this is a rare event,
+          // we simply do it lazily
+          this.env.qweb.off("update", this);
+        }
+      });
+    }
+    const qweb = this.env.qweb;
+
+    this.__owl__ = {
+      id: id,
+      vnode: null,
+      pvnode: null,
+      isMounted: false,
+      isDestroyed: false,
+      parent: p,
+      children: {},
+      cmap: {},
+      currentFiber: null,
+      boundHandlers: {},
+      mountedCB: null,
+      willUnmountCB: null,
+      willPatchCB: null,
+      patchedCB: null,
+      willStartCB: null,
+      willUpdatePropsCB: null,
+      observer: null,
+      renderFn: qweb.render.bind(qweb, this.__getTemplate(qweb)),
+      classObj: null,
+      refs: null
+    };
+  }
+
+  /**
+   * willStart is an asynchronous hook that can be implemented to perform some
+   * action before the initial rendering of a component.
+   *
+   * It will be called exactly once before the initial rendering. It is useful
+   * in some cases, for example, to load external assets (such as a JS library)
+   * before the component is rendered.
+   *
+   * Note that a slow willStart method will slow down the rendering of the user
+   * interface.  Therefore, some effort should be made to make this method as
+   * fast as possible.
+   *
+   * Note: this method should not be called manually.
+   */
+  async willStart() {}
+
+  /**
+   * mounted is a hook that is called each time a component is attached to the
+   * DOM. This is a good place to add some listeners, or to interact with the
+   * DOM, if the component needs to perform some measure for example.
+   *
+   * Note: this method should not be called manually.
+   *
+   * @see willUnmount
+   */
+  mounted() {}
+
+  /**
+   * The willUpdateProps is an asynchronous hook, called just before new props
+   * are set. This is useful if the component needs some asynchronous task
+   * performed, depending on the props (for example, assuming that the props are
+   * some record Id, fetching the record data).
+   *
+   * This hook is not called during the first render (but willStart is called
+   * and performs a similar job).
+   */
+  async willUpdateProps(nextProps: Props) {}
+
+  /**
+   * The willPatch hook is called just before the DOM patching process starts.
+   * It is not called on the initial render.  This is useful to get some
+   * information which are in the DOM.  For example, the current position of the
+   * scrollbar
+   */
+  willPatch(): any {}
+
+  /**
+   * This hook is called whenever a component did actually update its props,
+   * state or env.
+   *
+   * This method is not called on the initial render. It is useful to interact
+   * with the DOM (for example, through an external library) whenever the
+   * component was updated.
+   *
+   * Updating the component state in this hook is possible, but not encouraged.
+   * One need to be careful, because updates here will cause rerender, which in
+   * turn will cause other calls to updated. So, we need to be particularly
+   * careful at avoiding endless cycles.
+   */
+  patched() {}
+
+  /**
+   * willUnmount is a hook that is called each time just before a component is
+   * unmounted from the DOM. This is a good place to remove some listeners, for
+   * example.
+   *
+   * Note: this method should not be called manually.
+   *
+   * @see mounted
+   */
+  willUnmount() {}
+
+  /**
+   * catchError is a method called whenever some error happens in the rendering or
+   * lifecycle hooks of a child.
+   */
+  catchError(error: Error): void {}
+
+  //--------------------------------------------------------------------------
+  // Public
+  //--------------------------------------------------------------------------
+
+  /**
+   * Mount the component to a target element.
+   *
+   * This should only be done if the component was created manually. Components
+   * created declaratively in templates are managed by the Owl system.
+   *
+   * Note that a component can be mounted an unmounted several times
+   */
+  async mount(target: HTMLElement, renderBeforeRemount: boolean = false): Promise<void> {
+    const __owl__ = this.__owl__;
+    if (__owl__.isMounted) {
+      return Promise.resolve();
+    }
+    if (__owl__.vnode && !renderBeforeRemount) {
+      target.appendChild(this.el!);
+      if (document.body.contains(target)) {
+        this.__callMounted();
+      }
+      return;
+    }
+    const fiber = new Fiber(null, this, this.props, undefined, undefined, false);
+    if (!__owl__.vnode) {
+      this.__prepareAndRender(fiber);
+    } else {
+      this.__render(fiber);
+    }
+    return new Promise(resolve => {
+      scheduler.addFiber(fiber, () => {
+        if (!__owl__.isDestroyed) {
+          this.__patch(fiber.vnode);
+          target.appendChild(this.el!);
+          if (document.body.contains(target)) {
+            this.__callMounted();
+          }
+        }
+        resolve();
+      });
+    });
+  }
+
+  /**
+   * The unmount method is the opposite of the mount method.  It is useful
+   * to call willUnmount calls and remove the component from the DOM.
+   */
+  unmount() {
+    if (this.__owl__.isMounted) {
+      this.__callWillUnmount();
+      this.el!.remove();
+    }
+  }
+
+  /**
+   * The render method is the main entry point to render a component (once it
+   * is ready. This method is not initially called when the component is
+   * rendered the first time).
+   *
+   * This method will cause all its sub components to potentially rerender
+   * themselves.  Note that `render` is not called if a component is updated via
+   * its props.
+   */
+  async render(force: boolean = false): Promise<void> {
+    const __owl__ = this.__owl__;
+    if (
+      (!__owl__.isMounted && !__owl__.currentFiber) ||
+      (__owl__.currentFiber && !__owl__.currentFiber.isRendered)
+    ) {
+      return;
+    }
+    const fiber = new Fiber(null, this, this.props, undefined, undefined, force);
+    this.__render(fiber);
+    return new Promise(resolve => {
+      scheduler.addFiber(fiber.root, () => {
+        if (__owl__.isMounted && fiber === fiber.root) {
+          fiber.patchComponents();
+        }
+        resolve();
+      });
+    });
+  }
+
+  /**
+   * Destroy the component.  This operation is quite complex:
+   *  - it recursively destroy all children
+   *  - call the willUnmount hooks if necessary
+   *  - remove the dom node from the dom
+   *
+   * This should only be called manually if you created the component.  Most
+   * components will be automatically destroyed.
+   */
+  destroy() {
+    const __owl__ = this.__owl__;
+    if (!__owl__.isDestroyed) {
+      const el = this.el;
+      this.__destroy(__owl__.parent);
+      if (el) {
+        el.remove();
+      }
+    }
+  }
+
+  /**
+   * This method is called by the component system whenever its props are
+   * updated. If it returns true, then the component will be rendered.
+   * Otherwise, it will skip the rendering (also, its props will not be updated)
+   */
+  shouldUpdate(nextProps: Props): boolean {
+    return true;
+  }
+
+  /**
+   * Emit a custom event of type 'eventType' with the given 'payload' on the
+   * component's el, if it exists. However, note that the event will only bubble
+   * up to the parent DOM nodes. Thus, it must be called between mounted() and
+   * willUnmount().
+   */
+  trigger(eventType: string, payload?: any) {
+    if (this.el) {
+      const ev = new CustomEvent(eventType, {
+        bubbles: true,
+        cancelable: true,
+        detail: payload
+      });
+      this.el.dispatchEvent(ev);
+    }
+  }
+
+  //--------------------------------------------------------------------------
+  // Private
+  //--------------------------------------------------------------------------
+
+  /**
+   * Private helper to perform a full destroy, from the point of view of an Owl
+   * component. It does not remove the el (this is done only once on the top
+   * level destroyed component, for performance reasons).
+   *
+   * The job of this method is mostly to call willUnmount hooks, and to perform
+   * all necessary internal cleanup.
+   *
+   * Note that it does not call the __callWillUnmount method to avoid visiting
+   * all children many times.
+   */
+  __destroy(parent: Component<any, any> | null) {
+    const __owl__ = this.__owl__;
+    const isMounted = __owl__.isMounted;
+    if (isMounted) {
+      if (__owl__.willUnmountCB) {
+        __owl__.willUnmountCB();
+      }
+      this.willUnmount();
+      __owl__.isMounted = false;
+    }
+    const children = __owl__.children;
+    for (let key in children) {
+      children[key].__destroy(this);
+    }
+    if (parent) {
+      let id = __owl__.id;
+      delete parent.__owl__.children[id];
+      __owl__.parent = null;
+    }
+    __owl__.isDestroyed = true;
+    delete __owl__.vnode;
+  }
+
+  __callMounted() {
+    const __owl__ = this.__owl__;
+    const children = __owl__.children;
+    for (let id in children) {
+      const comp = children[id];
+      if (!comp.__owl__.isMounted && this.el!.contains(comp.el)) {
+        comp.__callMounted();
+      }
+    }
+    __owl__.isMounted = true;
+    try {
+      this.mounted();
+      if (__owl__.mountedCB) {
+        __owl__.mountedCB();
+      }
+    } catch (e) {
+      console.error(e); // TODO : add a test
+    }
+  }
+
+  __callWillUnmount() {
+    const __owl__ = this.__owl__;
+    if (__owl__.willUnmountCB) {
+      __owl__.willUnmountCB();
+    }
+    this.willUnmount();
+    __owl__.isMounted = false;
+    const children = __owl__.children;
+    for (let id in children) {
+      const comp = children[id];
+      if (comp.__owl__.isMounted) {
+        comp.__callWillUnmount();
+      }
+    }
+  }
+
+  /**
+   * The __updateProps method is called by the t-component directive whenever
+   * it updates a component (so, when the parent template is rerendered).
+   */
+  async __updateProps(
+    nextProps: Props,
+    parentFiber: Fiber,
+    scope: any,
+    vars: any,
+    previousSibling?: Fiber | null
+  ): Promise<void> {
+    const shouldUpdate = parentFiber.force || this.shouldUpdate(nextProps);
+    if (shouldUpdate) {
+      const __owl__ = this.__owl__;
+      const fiber = new Fiber(parentFiber, this, this.props, scope, vars, parentFiber.force);
+      if (!parentFiber.child) {
+        parentFiber.child = fiber;
+      } else {
+        previousSibling!.sibling = fiber;
+      }
+
+      const defaultProps = (<any>this.constructor).defaultProps;
+      if (defaultProps) {
+        nextProps = this.__applyDefaultProps(nextProps, defaultProps);
+      }
+      await Promise.all([
+        this.willUpdateProps(nextProps),
+        __owl__.willUpdatePropsCB && __owl__.willUpdatePropsCB(nextProps)
+      ]);
+      if (fiber.isCancelled) {
+        return;
+      }
+      this.props = nextProps;
+
+      this.__render(fiber);
+    }
+  }
+
+  /**
+   * Main patching method. We call the virtual dom patch method here to convert
+   * a virtual dom vnode into some actual dom.
+   */
+  __patch(vnode) {
+    const __owl__ = this.__owl__;
+    const target = __owl__.vnode || document.createElement(vnode.sel!);
+    __owl__.vnode = patch(target, vnode);
+    __owl__.currentFiber = null;
+  }
+
+  /**
+   * The __prepare method is only called by the t-component directive, when a
+   * subcomponent is created. It gets its scope and vars, if any, from the
+   * parent template.
+   */
+  __prepare(parentFiber: Fiber, scope: any, vars: any, previousSibling?: Fiber | null) {
+    const fiber = new Fiber(parentFiber, this, this.props, scope, vars, parentFiber.force);
+    fiber.shouldPatch = false;
+    if (!parentFiber.child) {
+      parentFiber.child = fiber;
+    } else {
+      previousSibling!.sibling = fiber;
+    }
+    return this.__prepareAndRender(fiber);
+  }
+
+  __getTemplate(qweb: QWeb): string {
+    let p = (<any>this).constructor;
+    if (!p.hasOwnProperty("_template")) {
+      if (p.template) {
+        p._template = p.template;
+      } else {
+        // here, the component and none of its superclasses defines a static `template`
+        // key. So we fall back on looking for a template matching its name (or
+        // one of its subclass).
+
+        let template: string;
+        while ((template = p.name) && !(template in qweb.templates) && p !== Component) {
+          p = p.__proto__;
+        }
+        if (p === Component) {
+          throw new Error(`Could not find template for component "${this.constructor.name}"`);
+        } else {
+          p._template = template;
+        }
+      }
+    }
+    return p._template;
+  }
+  async __prepareAndRender(fiber: Fiber) {
+    try {
+      await Promise.all([this.willStart(), this.__owl__.willStartCB && this.__owl__.willStartCB()]);
+    } catch (e) {
+      errorHandler(e, fiber);
+      fiber.vnode = h("div"); // -> we render this div at the end
+      return Promise.resolve();
+    }
+    if (this.__owl__.isDestroyed) {
+      return Promise.resolve();
+    }
+    if (!fiber.isCancelled) {
+      this.__render(fiber);
+    }
+  }
+
+  __render(fiber: Fiber) {
+    const __owl__ = this.__owl__;
+    if (__owl__.observer) {
+      __owl__.observer.allowMutations = false;
+    }
+    let vnode;
+    try {
+      vnode = __owl__.renderFn!(this, {
+        handlers: __owl__.boundHandlers,
+        fiber: fiber
+      });
+    } catch (e) {
+      vnode = __owl__.vnode || h("div");
+      errorHandler(e, fiber);
+    }
+    fiber.vnode = vnode;
+    if (__owl__.observer) {
+      __owl__.observer.allowMutations = true;
+    }
+
+    // we apply here the class information described on the component by the
+    // template (so, something like <MyComponent class="..."/>) to the actual
+    // root vnode
+    if (__owl__.classObj) {
+      vnode.data.class = Object.assign(vnode.data.class || {}, __owl__.classObj);
+    }
+    fiber.root.counter--;
+    fiber.isRendered = true;
+  }
+
+  /**
+   * Only called by qweb t-component directive
+   */
+  __mount(fiber: Fiber, elm: HTMLElement): VNode {
+    if (fiber !== this.__owl__.currentFiber) {
+      fiber = this.__owl__.currentFiber!; // TODO: check if we can remove fiber arg
+    }
+    const vnode = fiber.vnode!;
+    const __owl__ = this.__owl__;
+    if (__owl__.classObj) {
+      (<any>vnode).data.class = Object.assign((<any>vnode).data.class || {}, __owl__.classObj);
+    }
+    __owl__.vnode = patch(elm, vnode);
+    __owl__.currentFiber = null;
+    if (__owl__.parent!.__owl__.isMounted && !__owl__.isMounted) {
+      this.__callMounted();
+    }
+    return __owl__.vnode;
+  }
+
+  /**
+   * Only called by qweb t-component directive (when t-keepalive is set)
+   */
+  __remount() {
+    const __owl__ = this.__owl__;
+    if (!__owl__.isMounted) {
+      __owl__.isMounted = true;
+      this.mounted();
+    }
+  }
+
+  /**
+   * Apply default props (only top level).
+   *
+   * Note that this method does not modify in place the props, it returns a new
+   * prop object
+   */
+  __applyDefaultProps(props: Object | undefined, defaultProps: Object): Props {
+    props = props ? Object.assign({}, props) : {};
+    for (let propName in defaultProps) {
+      if (props![propName] === undefined) {
+        props![propName] = defaultProps[propName];
+      }
+    }
+    return <Props>props;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Error handling
+//------------------------------------------------------------------------------
+
+Fiber.prototype.handleError = function(error) {
+  errorHandler(error, this);
+};
+/**
+ * This is the global error handler for errors occurring in Owl main lifecycle
+ * methods.  Caught errors are triggered on the QWeb instance, and are
+ * potentially given to some parent component which implements `catchError`.
+ *
+ * If there are no such component, we destroy everything. This is better than
+ * being in a corrupted state.
+ */
+function errorHandler(error: Error, fiber: Fiber) {
+  let canCatch = false;
+  let component = fiber.component;
+  let qweb = component.env.qweb;
+  let root = component;
+  while (component && !(canCatch = component.catchError !== Component.prototype.catchError)) {
+    root = component;
+    component = component.__owl__.parent!;
+  }
+  console.error(error);
+  qweb.trigger("error", error);
+
+  if (canCatch) {
+    setTimeout(() => {
+      component.catchError(error);
+    });
+  } else {
+    root.destroy();
+  }
+}

src/component/directive.ts

@@ -0,0 +1,511 @@
+import { QWeb } from "../qweb/index";
+import { INTERP_REGEXP } from "../qweb/compilation_context";
+import { MODS_CODE } from "../qweb/extensions";
+
+//------------------------------------------------------------------------------
+// t-component
+//------------------------------------------------------------------------------
+
+const T_COMPONENT_MODS_CODE = Object.assign({}, MODS_CODE, {
+  self: "if (e.target !== vn.elm) {return}"
+});
+
+QWeb.utils.defineProxy = function defineProxy(target, source) {
+  for (let k in source) {
+    Object.defineProperty(target, k, {
+      get() {
+        return source[k];
+      },
+      set(val) {
+        source[k] = val;
+      }
+    });
+  }
+};
+
+/**
+ * The t-component directive is certainly a complicated and hard to maintain piece
+ * of code.  To help you, fellow developer, if you have to maintain it, I offer
+ * you this advice: Good luck...
+ *
+ * Since it is not 'direct' code, but rather code that generates other code, it
+ * is not easy to understand.  To help you, here  is a detailed and commented
+ * explanation of the code generated by the t-component directive for the following
+ * situation:
+ * ```xml
+ *   <Child
+ *      t-key="'somestring'"
+ *      flag="state.flag"
+ *      t-transition="fade"/>
+ * ```
+ *
+ * ```js
+ * // we assign utils on top of the function because it will be useful for
+ * // each components
+ * let utils = this.utils;
+ *
+ * // this is the virtual node representing the parent div
+ * let c1 = [], p1 = { key: 1 };
+ * var vn1 = h("div", p1, c1);
+ *
+ * // t-component directive: we start by evaluating the expression given by t-key:
+ * let key5 = "somestring";
+ *
+ * // def3 is the promise that will contain later either the new component
+ * // creation, or the props update...
+ * let def3;
+ *
+ * // this is kind of tricky: we need here to find if the component was already
+ * // created by a previous rendering.  This is done by checking the internal
+ * // `cmap` (children map) of the parent component: it maps keys to component ids,
+ * // and, then, if there is an id, we look into the children list to get the
+ * // instance
+ * let w4 =
+ *   key5 in context.__owl__.cmap
+ *   ? context.__owl__.children[context.__owl__.cmap[key5]]
+ *   : false;
+ *
+ * // We keep the index of the position of the component in the closure.  We push
+ * // null to reserve the slot, and will replace it later by the component vnode,
+ * // when it will be ready (do not forget that preparing/rendering a component is
+ * // asynchronous)
+ * let _2_index = c1.length;
+ * c1.push(null);
+ *
+ * // we evaluate here the props given to the component. It is done here to be
+ * // able to easily reference it later, and also, it might be an expensive
+ * // computation, so it is certainly better to do it only once
+ * let props4 = { flag: context["state"].flag };
+ *
+ * // If we have a component, currently rendering, but not ready yet, we do not want
+ * // to wait for it to be ready if we can avoid it
+ * if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
+ *   // we check if the props are the same.  In that case, we can simply reuse
+ *   // the previous rendering and skip all useless work
+ *   if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
+ *     def3 = w4.__owl__.renderPromise;
+ *   } else {
+ *     // if the props are not the same, we destroy the component and starts anew.
+ *     // this will be faster than waiting for its rendering, then updating it
+ *     w4.destroy();
+ *     w4 = false;
+ *   }
+ * }
+ *
+ * if (!w4) {
+ *   // in this situation, we need to create a new component.  First step is
+ *   // to get a reference to the class, then create an instance with
+ *   // current context as parent, and the props.
+ *   let W4 = context.component && context.components[componentKey4] || QWeb.component[componentKey4];
+
+ *   if (!W4) {
+ *     throw new Error("Cannot find the definition of component 'child'");
+ *   }
+ *   w4 = new W4(owner, props4);
+ *
+ *   // Whenever we rerender the parent component, we need to be sure that we
+ *   // are able to find the component instance. To do that, we register it to
+ *   // the parent cmap (children map).  Note that the 'template' key is
+ *   // used here, since this is what identify the component from the template
+ *   // perspective.
+ *   context.__owl__.cmap[key5] = w4.__owl__.id;
+ *
+ *   // __prepare is called, to basically call willStart, then render the
+ *   // component
+ *   def3 = w4.__prepare();
+ *
+ *   def3 = def3.then(vnode => {
+ *     // we create here a virtual node for the parent (NOT the component). This
+ *     // means that the vdom of the parent will be stopped here, and from
+ *     // the parent's perspective, it simply is a vnode with no children.
+ *     // However, it shares the same dom element with the component root
+ *     // vnode.
+ *     let pvnode = h(vnode.sel, { key: key5 });
+ *
+ *     // we add hooks to the parent vnode so we can interact with the new
+ *     // component at the proper time
+ *     pvnode.data.hook = {
+ *       insert(vn) {
+ *         // the __mount method will patch the component vdom into the elm vn.elm,
+ *         // then call the mounted hooks. However, suprisingly, the snabbdom
+ *         // patch method actually replace the elm by a new elm, so we need
+ *         // to synchronise the pvnode elm with the resulting elm
+ *         let nvn = w4.__mount(vnode, vn.elm);
+ *         pvnode.elm = nvn.elm;
+ *         // what follows is only present if there are animations on the component
+ *         utils.transitionInsert(vn, "fade");
+ *       },
+ *       remove() {
+ *         // override with empty function to prevent from removing the node
+ *         // directly. It will be removed when destroy is called anyway, which
+ *         // delays the removal if there are animations.
+ *       },
+ *       destroy() {
+ *         // if there are animations, we delay the call to destroy on the
+ *         // component, if not, we call it directly.
+ *         let finalize = () => {
+ *           w4.destroy();
+ *         };
+ *         utils.transitionRemove(vn, "fade", finalize);
+ *       }
+ *     };
+ *     // the pvnode is inserted at the correct position in the div's children
+ *     c1[_2_index] = pvnode;
+ *
+ *     // we keep here a reference to the parent vnode (representing the
+ *     // component, so we can reuse it later whenever we update the component
+ *     w4.__owl__.pvnode = pvnode;
+ *   });
+ * } else {
+ *   // this is the 'update' path of the directive.
+ *   // the call to __updateProps is the actual component update
+ *   // Note that we only update the props if we cannot reuse the previous
+ *   // rendering work (in the case it was rendered with the same props)
+ *   def3 = def3 || w4.__updateProps(props4, extra.forceUpdate, extra.patchQueue);
+ *   def3 = def3.then(() => {
+ *     // if component was destroyed in the meantime, we do nothing (so, this
+ *     // means that the parent's element children list will have a null in
+ *     // the component's position, which will cause the pvnode to be removed
+ *     // when it is patched.
+ *     if (w4.__owl__.isDestroyed) {
+ *       return;
+ *     }
+ *     // like above, we register the pvnode to the children list, so it
+ *     // will not be patched out of the dom.
+ *     let pvnode = w4.__owl__.pvnode;
+ *     c1[_2_index] = pvnode;
+ *   });
+ * }
+ *
+ * // we register the deferred here so the parent can coordinate its patch operation
+ * // with all the children.
+ * extra.promises.push(def3);
+ * return vn1;
+ * ```
+ */
+
+QWeb.addDirective({
+  name: "component",
+  extraNames: ["props", "keepalive"],
+  priority: 100,
+  atNodeEncounter({ ctx, value, node, qweb }): boolean {
+    ctx.addLine("//COMPONENT");
+    ctx.rootContext.shouldDefineOwner = true;
+    ctx.rootContext.shouldDefineQWeb = true;
+    ctx.rootContext.shouldDefineParent = true;
+    ctx.rootContext.shouldDefineUtils = true;
+    let keepAlive = node.getAttribute("t-keepalive") ? true : false;
+    let hasDynamicProps = node.getAttribute("t-props") ? true : false;
+
+    // t-on- events and t-transition
+    const events: [string, string[], string, string][] = [];
+    let transition: string = "";
+    const attributes = (<Element>node).attributes;
+    const props: { [key: string]: string } = {};
+    for (let i = 0; i < attributes.length; i++) {
+      const name = attributes[i].name;
+      const value = attributes[i].textContent!;
+      if (name.startsWith("t-on-")) {
+        const [eventName, ...mods] = name.slice(5).split(".");
+        let extraArgs;
+        let handlerValue = value.replace(/\(.*\)/, function(args) {
+          extraArgs = args.slice(1, -1);
+          return "";
+        });
+        events.push([eventName, mods, handlerValue, extraArgs]);
+      } else if (name === "t-transition") {
+        transition = value;
+      } else if (!name.startsWith("t-")) {
+        if (name !== "class" && name !== "style") {
+          // this is a prop!
+          props[name] = ctx.formatExpression(value);
+        }
+      }
+    }
+
+    let key = node.getAttribute("t-key");
+    if (key) {
+      key = ctx.formatExpression(key);
+    }
+
+    // computing the props string representing the props object
+    let propStr = Object.keys(props)
+      .map(k => k + ":" + props[k])
+      .join(",");
+    let defID = ctx.generateID();
+    let componentID = ctx.generateID();
+    let keyID = key && ctx.generateID();
+    if (key) {
+      // we bind a variable to the key (could be a complex expression, so we
+      // want to evaluate it only once)
+      ctx.addLine(`let key${keyID} = 'key' + ${key};`);
+    }
+
+    let locationExpr = `\`__${ctx.generateID()}__`;
+    for (let i = 0; i < ctx.loopNumber - 1; i++) {
+      locationExpr += `\${i${i + 1}}__`;
+    }
+    if (key || ctx.currentKey) {
+      const k = key ? `key${keyID}` : ctx.currentKey;
+      ctx.addLine(`let templateId${componentID} = ${locationExpr}\` + ${k};`);
+    } else {
+      locationExpr += ctx.loopNumber ? `\${i${ctx.loopNumber}}__\`` : "`";
+      ctx.addLine(`let templateId${componentID} = ${locationExpr};`);
+    }
+    const templateId = `templateId${componentID}`;
+
+    let ref = node.getAttribute("t-ref");
+    let refExpr = "";
+    let refKey: string = "";
+    if (ref) {
+      ctx.rootContext.shouldDefineRefs = true;
+      refKey = `ref${ctx.generateID()}`;
+      ctx.addLine(`const ${refKey} = ${ctx.interpolate(ref)};`);
+      refExpr = `context.__owl__.refs[${refKey}] = w${componentID};`;
+    }
+    let transitionsInsertCode = "";
+    if (transition) {
+      transitionsInsertCode = `utils.transitionInsert(vn, '${transition}');`;
+    }
+    let finalizeComponentCode = `w${componentID}.${keepAlive ? "unmount" : "destroy"}();`;
+    if (ref && !keepAlive) {
+      finalizeComponentCode += `delete context.__owl__.refs[${refKey}];`;
+    }
+    if (transition) {
+      finalizeComponentCode = `let finalize = () => {
+          ${finalizeComponentCode}
+        };
+        utils.transitionRemove(vn, '${transition}', finalize);`;
+    }
+
+    let createHook = "";
+    let classAttr = node.getAttribute("class");
+    let tattClass = node.getAttribute("t-att-class");
+    let styleAttr = node.getAttribute("style");
+    let tattStyle = node.getAttribute("t-att-style");
+    if (tattStyle) {
+      const attVar = `_${ctx.generateID()}`;
+      ctx.addLine(`const ${attVar} = ${ctx.formatExpression(tattStyle)};`);
+      tattStyle = attVar;
+    }
+    let classObj = "";
+    if (classAttr || tattClass || styleAttr || tattStyle || events.length) {
+      if (classAttr) {
+        let classDef = classAttr
+          .trim()
+          .split(/\s+/)
+          .map(a => `'${a}':true`)
+          .join(",");
+        classObj = `_${ctx.generateID()}`;
+        ctx.addLine(`let ${classObj} = {${classDef}};`);
+      }
+      if (tattClass) {
+        let tattExpr = ctx.formatExpression(tattClass);
+        if (tattExpr[0] !== "{" || tattExpr[tattExpr.length - 1] !== "}") {
+          tattExpr = `utils.toObj(${tattExpr})`;
+        }
+        if (classAttr) {
+          ctx.addLine(`Object.assign(${classObj}, ${tattExpr})`);
+        } else {
+          classObj = `_${ctx.generateID()}`;
+          ctx.addLine(`let ${classObj} = ${tattExpr};`);
+        }
+      }
+      let eventsCode = events
+        .map(function([eventName, mods, handlerValue, extraArgs]) {
+          let params = "owner";
+          if (extraArgs) {
+            if (ctx.loopNumber) {
+              let argId = ctx.generateID();
+              // we need to evaluate the arguments now, because the handler will
+              // be set asynchronously later when the widget is ready, and the
+              // context might be different.
+              ctx.addLine(`let arg${argId} = ${ctx.formatExpression(extraArgs)};`);
+              params = `owner, arg${argId}`;
+            } else {
+              params = `owner, ${ctx.formatExpression(extraArgs)}`;
+            }
+          }
+          let handler = `function (e) {`;
+          handler += mods
+            .map(function(mod) {
+              return T_COMPONENT_MODS_CODE[mod];
+            })
+            .join("");
+          if (handlerValue) {
+            handler += `const fn = owner['${handlerValue}'];`;
+            handler += `if (fn) { fn.call(${params}, e); } else { owner.${handlerValue}; }`;
+          }
+          handler += `}`;
+          return `vn.elm.addEventListener('${eventName}', ${handler});`;
+        })
+        .join("");
+      const styleExpr = tattStyle || (styleAttr ? `'${styleAttr}'` : false);
+      const styleCode = styleExpr ? `vn.elm.style = ${styleExpr};` : "";
+      createHook = `vnode.data.hook = {create(_, vn){${styleCode}${eventsCode}}};`;
+    }
+
+    ctx.addLine(
+      `let w${componentID} = ${templateId} in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[${templateId}]] : false;`
+    );
+    let shouldProxy = !ctx.parentNode;
+    if (keepAlive) {
+      ctx.addLine(
+        `const fiber${componentID} = Object.assign(Object.create(extra.fiber), {patchQueue: []});`
+      );
+    }
+    if (shouldProxy) {
+      let id = ctx.generateID();
+      ctx.rootContext.rootNode = id;
+      shouldProxy = true;
+      ctx.rootContext.shouldDefineResult = true;
+      ctx.addLine(`let vn${id} = {};`);
+      ctx.addLine(`result = vn${id};`);
+    }
+    if (hasDynamicProps) {
+      const dynamicProp = ctx.formatExpression(node.getAttribute("t-props")!);
+      ctx.addLine(`let props${componentID} = Object.assign({${propStr}}, ${dynamicProp});`);
+    } else {
+      ctx.addLine(`let props${componentID} = {${propStr}};`);
+    }
+    ctx.addIf(
+      `w${componentID} && w${componentID}.__owl__.currentFiber && !w${componentID}.__owl__.vnode`
+    );
+    ctx.addLine(`w${componentID}.destroy();`);
+    ctx.addLine(`w${componentID} = false;`);
+    ctx.closeIf();
+
+    let registerCode = "";
+    if (shouldProxy) {
+      registerCode = `utils.defineProxy(vn${ctx.rootNode}, pvnode);`;
+    }
+
+    // SLOTS
+    const varDefs: string[] = [];
+    const hasSlots = node.childNodes.length;
+    if (hasSlots) {
+      ctx.rootContext.shouldTrackScope = true;
+      for (let v of Object.values(ctx.variables)) {
+        if (v["id"]) {
+          varDefs.push(v["id"]);
+        }
+      }
+    }
+
+    let scopeVars;
+    if (hasSlots) {
+      let scope = ctx.scopeVars.length ? `Object.assign({}, scope)` : `{}`;
+      let vars = varDefs.length ? `{${varDefs.join(",")}}` : "undefined";
+      scopeVars = `${scope}, ${vars}`;
+    } else {
+      scopeVars = "undefined, undefined";
+    }
+
+    ctx.addIf(`w${componentID}`);
+
+    // need to update component
+    let patchQueueCode = keepAlive ? `fiber${componentID}` : "extra.fiber";
+    if (keepAlive) {
+      // if we have t-keepalive="1", the component could be unmounted, but then
+      // we __updateProps is called.  This is ok, but we do not want to call
+      // the willPatch/patched hooks of the component in this case, so we
+      // disable the patch queue
+      patchQueueCode = `w${componentID}.__owl__.isMounted ? extra.fiber : fiber${componentID}`;
+    }
+    if (QWeb.dev) {
+      ctx.addLine(`utils.validateProps(w${componentID}.constructor, props${componentID})`);
+    }
+    let styleCode = "";
+    if (tattStyle) {
+      styleCode = `.then(()=>{if (w${componentID}.__owl__.isDestroyed) {return};w${componentID}.el.style=${tattStyle};});`;
+    }
+    ctx.addLine(
+      `w${componentID}.__updateProps(props${componentID}, ${patchQueueCode}${scopeVars &&
+        ", " + scopeVars}, sibling)${styleCode};`
+    );
+    ctx.addLine(`let pvnode = w${componentID}.__owl__.pvnode;`);
+    let keepAliveCode = "";
+    if (keepAlive) {
+      keepAliveCode = `pvnode.data.hook.insert = vn => {vn.elm.parentNode.replaceChild(w${componentID}.el,vn.elm);vn.elm=w${componentID}.el;w${componentID}.__remount();};`;
+      ctx.addLine(keepAliveCode);
+    }
+    if (registerCode) {
+      ctx.addLine(registerCode);
+    }
+    if (ctx.parentNode) {
+      ctx.addLine(`c${ctx.parentNode}.push(pvnode);`);
+    }
+
+    ctx.addElse();
+
+    // new component
+    let dynamicFallback = "";
+    if (!value.match(INTERP_REGEXP)) {
+      dynamicFallback = `|| ${ctx.formatExpression(value)}`;
+    }
+    const interpValue = ctx.interpolate(value);
+    ctx.addLine(`let componentKey${componentID} = ${interpValue};`);
+    ctx.addLine(
+      `let W${componentID} = context.constructor.components[componentKey${componentID}] || QWeb.components[componentKey${componentID}]${dynamicFallback};`
+    );
+
+    // maybe only do this in dev mode...
+    ctx.addLine(
+      `if (!W${componentID}) {throw new Error('Cannot find the definition of component "' + componentKey${componentID} + '"')}`
+    );
+    ctx.addLine(`w${componentID} = new W${componentID}(parent, props${componentID});`);
+    ctx.addLine(`parent.__owl__.cmap[${templateId}] = w${componentID}.__owl__.id;`);
+
+    if (hasSlots) {
+      const clone = <Element>node.cloneNode(true);
+      const slotNodes = clone.querySelectorAll("[t-set]");
+      const slotId = QWeb.nextSlotId++;
+      ctx.addLine(`w${componentID}.__owl__.slotId = ${slotId};`);
+      if (slotNodes.length) {
+        for (let i = 0, length = slotNodes.length; i < length; i++) {
+          const slotNode = slotNodes[i];
+          slotNode.parentElement!.removeChild(slotNode);
+          const key = slotNode.getAttribute("t-set")!;
+          slotNode.removeAttribute("t-set");
+          const slotFn = qweb._compile(`slot_${key}_template`, slotNode, ctx);
+          QWeb.slots[`${slotId}_${key}`] = slotFn;
+        }
+      }
+      if (clone.childNodes.length) {
+        const t = clone.ownerDocument!.createElement("t");
+        for (let child of Object.values(clone.childNodes)) {
+          t.appendChild(child);
+        }
+        const slotFn = qweb._compile(`slot_default_template`, t, ctx);
+        QWeb.slots[`${slotId}_default`] = slotFn;
+      }
+    }
+
+    ctx.addLine(`let def${defID} = w${componentID}.__prepare(extra.fiber, ${scopeVars}, sibling);`);
+    // hack: specify empty remove hook to prevent the node from being removed from the DOM
+    ctx.addLine(
+      `let pvnode = h('dummy', {key: ${templateId}, hook: {insert(vn) { let nvn=w${componentID}.__mount(fiber, pvnode.elm);pvnode.elm=nvn.elm;${refExpr}${transitionsInsertCode}},remove() {},destroy(vn) {${finalizeComponentCode}}}});`
+    );
+    ctx.addLine(`const fiber = w${componentID}.__owl__.currentFiber;`);
+    ctx.addLine(
+      `def${defID}.then(function () {if (w${componentID}.__owl__.isDestroyed) {return;} const vnode = fiber.vnode; pvnode.sel = vnode.sel; ${createHook}});`
+    );
+    if (registerCode) {
+      ctx.addLine(registerCode);
+    }
+    if (ctx.parentNode) {
+      ctx.addLine(`c${ctx.parentNode}.push(pvnode);`);
+    }
+    ctx.addLine(`w${componentID}.__owl__.pvnode = pvnode;`);
+
+    ctx.closeIf();
+
+    if (classObj) {
+      ctx.addLine(`w${componentID}.__owl__.classObj=${classObj};`);
+    }
+
+    ctx.addLine(`sibling = w${componentID}.__owl__.currentFiber || sibling;`);
+
+    return true;
+  }
+});

src/component/fiber.ts

@@ -0,0 +1,199 @@
+import { VNode } from "../vdom/index";
+import { Component } from "./component";
+
+/**
+ * Owl Fiber Class
+ *
+ * Fibers are small abstractions designed to contain all the internal state
+ * associated with a "rendering work unit", relative to a specific component.
+ *
+ * A rendering will cause the creation of a fiber for each impacted components.
+ *
+ * Fibers capture all that necessary information, which is critical to owl
+ * asynchronous rendering pipeline. Fibers can be cancelled, can be in different
+ * states and in general determine the state of the rendering.
+ */
+
+export class Fiber {
+  // The force attribute determines if a rendering should bypass the `shouldUpdate`
+  // method potentially implemented by a component. It is usually set to false.
+  force: boolean;
+
+  // isCancelled means that the rendering corresponding to this fiber and its
+  // children is cancelled. No extra work should be done.
+  isCancelled: boolean = false;
+
+  // the fibers corresponding to component updates (updateProps) need to call
+  // the willPatch and patched hooks from the corresponding component. However,
+  // fibers corresponding to a new component do not need to do that. So, the
+  // shouldPatch hook is the boolean that we check whenever we need to apply
+  // a patch.
+  shouldPatch: boolean = true;
+
+  // isRendered is the last state of a fiber. If true, this means that it has
+  // been rendered and is inert (so, it should not be taken into account when
+  // counting the number of active fibers).
+  isRendered: boolean = false;
+
+  // the counter number is a critical information. It is only necessary for a
+  // root fiber.  For that fiber, this number counts the number of active sub
+  // fibers.  When that number reaches 0, the fiber can be applied by the
+  // scheduler.
+  counter: number = 0;
+
+  scope: any;
+  vars: any;
+  props: any;
+
+  component: Component<any, any>;
+  vnode: VNode | null = null;
+
+  root: Fiber;
+  child: Fiber | null = null;
+  sibling: Fiber | null = null;
+  parent: Fiber | null = null;
+
+  constructor(parent: Fiber | null, component: Component<any, any>, props, scope, vars, force) {
+    this.force = force;
+    this.scope = scope;
+    this.vars = vars;
+    this.props = props;
+    this.component = component;
+
+    this.root = parent ? parent.root : this;
+    this.parent = parent;
+
+    let oldFiber = component.__owl__.currentFiber;
+    if (oldFiber && !oldFiber.isCancelled) {
+      this._remapFiber(oldFiber);
+    }
+
+    this.root.counter++;
+
+    component.__owl__.currentFiber = this;
+  }
+
+  /**
+   * In some cases, a rendering initiated at some component can detect that it
+   * should be part of a larger rendering initiated somewhere up the component
+   * tree.  In that case, it needs to cancel the previous rendering and
+   * remap itself as a part of the current parent rendering.
+   */
+  _remapFiber(oldFiber: Fiber) {
+    oldFiber.cancel();
+    if (oldFiber === oldFiber.root) {
+      oldFiber.root.counter++;
+    }
+    if (oldFiber.parent && !this.parent) {
+      // re-map links
+      this.parent = oldFiber.parent;
+      this.root = this.parent.root;
+      this.sibling = oldFiber.sibling;
+      if (this.parent.child === oldFiber) {
+        this.parent.child = this;
+      } else {
+        let current = this.parent.child!;
+        while (true) {
+          if (current.sibling === oldFiber) {
+            current.sibling = this;
+            break;
+          }
+          current = current.sibling!;
+        }
+      }
+    }
+  }
+
+  /**
+   * This function has been taken from
+   * https://medium.com/react-in-depth/the-how-and-why-on-reacts-usage-of-linked-list-in-fiber-67f1014d0eb7
+   */
+  _walk(doWork: (f: Fiber) => Fiber | null) {
+    let root = this;
+    let current: Fiber = this;
+    while (true) {
+      const child = doWork(current);
+      if (child) {
+        current = child;
+        continue;
+      }
+      if (current === root) {
+        return;
+      }
+      while (!current.sibling) {
+        if (!current.parent || current.parent === root) {
+          return;
+        }
+        current = current.parent;
+      }
+      current = current.sibling;
+    }
+  }
+
+  /**
+   * Apply the given patch queue from a fiber.
+   *   1) Call 'willPatch' on the component of each patch
+   *   2) Call '__patch' on the component of each patch
+   *   3) Call 'patched' on the component of each patch, in reverse order
+   */
+  patchComponents() {
+    const patchQueue: Fiber[] = [];
+    const doWork: (Fiber) => Fiber | null = function(f) {
+      if (f.shouldPatch) {
+        patchQueue.push(f);
+      }
+      return f.child;
+    };
+    this._walk(doWork);
+    let component: Component<any, any> = this.component;
+    this.shouldPatch = false;
+    const patchLen = patchQueue.length;
+    try {
+      for (let i = 0; i < patchLen; i++) {
+        component = patchQueue[i].component;
+        if (component.__owl__.willPatchCB) {
+          component.__owl__.willPatchCB();
+        }
+        component.willPatch();
+      }
+    } catch (e) {
+      console.error(e);
+    }
+    try {
+      for (let i = 0; i < patchLen; i++) {
+        const fiber = patchQueue[i];
+        component = fiber.component;
+        component.__patch(fiber.vnode);
+      }
+    } catch (e) {
+      this.handleError(e);
+    }
+    try {
+      for (let i = patchLen - 1; i >= 0; i--) {
+        component = patchQueue[i].component;
+        component.patched();
+        if (component.__owl__.patchedCB) {
+          component.__owl__.patchedCB();
+        }
+      }
+    } catch (e) {
+      console.error(e);
+    }
+    this.shouldPatch = true;
+  }
+
+  /**
+   * Cancel a fiber and all its children.
+   */
+  cancel() {
+    this._walk(f => {
+      if (!f.isRendered) {
+        f.root.counter--;
+      }
+      f.isCancelled = true;
+      return f.child;
+    });
+  }
+
+  handleError(e: Error) {}
+}

src/component/props_validation.ts

@@ -0,0 +1,96 @@
+import { QWeb } from "../qweb/index";
+
+//------------------------------------------------------------------------------
+// Prop validation helper
+//------------------------------------------------------------------------------
+
+/**
+ * Validate the component props (or next props) against the (static) props
+ * description.  This is potentially an expensive operation: it may needs to
+ * visit recursively the props and all the children to check if they are valid.
+ * This is why it is only done in 'dev' mode.
+ */
+
+QWeb.utils.validateProps = function(Widget, props: Object) {
+  const propsDef = (<any>Widget).props;
+  if (propsDef instanceof Array) {
+    // list of strings (prop names)
+    for (let i = 0, l = propsDef.length; i < l; i++) {
+      const propName = propsDef[i];
+      if (propName[propName.length - 1] === "?") {
+        // optional prop
+        break;
+      }
+      if (!props[propName]) {
+        throw new Error(`Missing props '${propsDef[i]}' (component '${Widget.name}')`);
+      }
+    }
+    for (let key in props) {
+      if (!propsDef.includes(key) && !propsDef.includes(key + "?")) {
+        throw new Error(`Unknown prop '${key}' given to component '${Widget.name}'`);
+      }
+    }
+  } else if (propsDef) {
+    // propsDef is an object now
+    for (let propName in propsDef) {
+      if (props[propName] === undefined) {
+        if (propsDef[propName] && !propsDef[propName].optional) {
+          throw new Error(`Missing props '${propName}' (component '${Widget.name}')`);
+        } else {
+          break;
+        }
+      }
+      let isValid = isValidProp(props[propName], propsDef[propName]);
+      if (!isValid) {
+        throw new Error(`Props '${propName}' of invalid type in component '${Widget.name}'`);
+      }
+    }
+    for (let propName in props) {
+      if (!(propName in propsDef)) {
+        throw new Error(`Unknown prop '${propName}' given to component '${Widget.name}'`);
+      }
+    }
+  }
+};
+
+/**
+ * Check if an invidual prop value matches its (static) prop definition
+ */
+function isValidProp(prop, propDef): boolean {
+  if (propDef === true) {
+    return true;
+  }
+  if (typeof propDef === "function") {
+    // Check if a value is constructed by some Constructor.  Note that there is a
+    // slight abuse of language: we want to consider primitive values as well.
+    //
+    // So, even though 1 is not an instance of Number, we want to consider that
+    // it is valid.
+    if (typeof prop === "object") {
+      return prop instanceof propDef;
+    }
+    return typeof prop === propDef.name.toLowerCase();
+  } else if (propDef instanceof Array) {
+    // If this code is executed, this means that we want to check if a prop
+    // matches at least one of its descriptor.
+    let result = false;
+    for (let i = 0, iLen = propDef.length; i < iLen; i++) {
+      result = result || isValidProp(prop, propDef[i]);
+    }
+    return result;
+  }
+  // propsDef is an object
+  let result = isValidProp(prop, propDef.type);
+  if (propDef.type === Array) {
+    for (let i = 0, iLen = prop.length; i < iLen; i++) {
+      result = result && isValidProp(prop[i], propDef.element);
+    }
+  }
+  if (propDef.type === Object) {
+    const shape = propDef.shape;
+    for (let key in shape) {
+      result = result && isValidProp(prop[key], shape[key]);
+    }
+  }
+  return result;
+}

src/component/scheduler.ts

@@ -0,0 +1,67 @@
+import { Fiber } from "./fiber";
+
+/**
+ * Owl Scheduler Class
+ *
+ * The scheduler is the part of Owl that will effectively apply a rendering
+ * whenever a fiber is ready.
+ *
+ * Briefly, it can be used to register root fibers.  Whenever there is an
+ * active root fiber, it will poll continuously each animation frame (so, about
+ * once every 16ms) and whenever a root fiber is ready, it will apply it.
+ */
+
+interface Task {
+  fiber: Fiber;
+  callback: () => void;
+}
+
+export class Scheduler {
+  tasks: Task[] = [];
+  isRunning: boolean = false;
+  requestAnimationFrame: typeof window.requestAnimationFrame;
+
+  constructor(requestAnimationFrame) {
+    this.requestAnimationFrame = requestAnimationFrame;
+  }
+
+  addFiber(fiber, callback) {
+    this.tasks.push({ fiber, callback });
+    if (this.isRunning) {
+      return;
+    }
+    this.scheduleTasks();
+  }
+
+  /**
+   * Process all current tasks. This only applies to the fibers that are ready.
+   * Other tasks are left unchanged.
+   */
+  flush() {
+    let tasks = this.tasks;
+    this.tasks = [];
+    tasks = tasks.filter(task => {
+      if (task.fiber.isCancelled) {
+        return false;
+      }
+      if (task.fiber.counter === 0) {
+        task.callback();
+        return false;
+      }
+      return true;
+    });
+    this.tasks = tasks.concat(this.tasks);
+  }
+
+  scheduleTasks() {
+    this.isRunning = true;
+    this.requestAnimationFrame(() => {
+      this.flush();
+      if (this.tasks.length > 0) {
+        this.scheduleTasks();
+      } else {
+        this.isRunning = false;
+      }
+    });
+  }
+}

src/context.ts

@@ -0,0 +1,111 @@
+import { Component, scheduler } from "./component/component";
+import { EventBus } from "./core/event_bus";
+import { Observer } from "./core/observer";
+import { onWillUnmount } from "./hooks";
+/**
+ * The `Context` object provides a way to share data between an arbitrary number
+ * of component. Usually, data is passed from a parent to its children component,
+ * but when we have to deal with some mostly global information, this can be
+ * annoying, since each component will need to pass the information to each
+ * children, even though some or most of them will not use the information.
+ *
+ * With a `Context` object, each component can subscribe (with the `useContext`
+ * hook) to its state, and will be updated whenever the context state is updated.
+ */
+export class Context extends EventBus {
+  state: any;
+  observer: Observer;
+  rev: number = 1;
+  // mapping from component id to last observed context id
+  mapping: { [componentId: number]: number } = {};
+
+  constructor(state: Object = {}) {
+    super();
+    this.observer = new Observer();
+    this.observer.notifyCB = this.__notifyComponents.bind(this);
+    this.state = this.observer.observe(state);
+  }
+
+  /**
+   * Instead of using trigger to emit an update event, we actually implement
+   * our own function to do that.  The reason is that we need to be smarter than
+   * a simple trigger function: we need to wait for parent components to be
+   * done before doing children components.  The reason is that if an update
+   * as an effect of destroying a children, we do not want to call the
+   * mapStoreToProps function of the child, nor rendering it.
+   *
+   * This method is not optimal if we have a bunch of asynchronous components:
+   * we wait sequentially for each component to be completed before updating the
+   * next.  However, the only things that matters is that children are updated
+   * after their parents.  So, this could be optimized by being smarter, and
+   * updating all widgets concurrently, except for parents/children.
+   *
+   * A potential cheap way to improve this situation is to keep track of the
+   * depth of a component in the component tree. A root component has a depth of
+   * 1, then its children of 2 and so on... Then, we can update all components
+   * with the same depth in parallel.
+   */
+  async __notifyComponents() {
+    const rev = ++this.rev;
+    const subs = this.subscriptions.update || [];
+    for (let i = 0, iLen = subs.length; i < iLen; i++) {
+      const sub = subs[i];
+      const shouldCallback = sub.owner ? sub.owner.__owl__.isMounted : true;
+      if (shouldCallback) {
+        const render = sub.callback.call(sub.owner, rev);
+        scheduler.flush();
+        await render;
+      }
+    }
+  }
+}
+
+/**
+ * The`useContext` hook is the normal way for a component to register themselve
+ * to context state changes. The `useContext` method returns the context state
+ */
+export function useContext(ctx: Context): any {
+  const component: Component<any, any> = Component.current!;
+  return useContextWithCB(ctx, component, component.render.bind(component));
+}
+
+export function useContextWithCB(ctx: Context, component: Component<any, any>, method): any {
+  const __owl__ = component.__owl__;
+  const id = __owl__.id;
+  const mapping = ctx.mapping;
+  if (id in mapping) {
+    return ctx.state;
+  }
+  if (!__owl__.observer) {
+    __owl__.observer = new Observer();
+    __owl__.observer.notifyCB = component.render.bind(component);
+  }
+  const currentCB = __owl__.observer.notifyCB;
+  __owl__.observer.notifyCB = function () {
+      if (ctx.rev > mapping[id]) {
+          // in this case, the context has been updated since we were rendering
+          // last, and we do not need to render here with the observer. A
+          // rendering is coming anyway, with the correct props.
+          return;
+      }
+      currentCB();
+  }
+
+  mapping[id] = 0;
+  const renderFn = __owl__.renderFn;
+  __owl__.renderFn = function(comp, params) {
+    mapping[id] = ctx.rev;
+    return renderFn(comp, params);
+  };
+  ctx.on("update", component, async contextRev => {
+    if (mapping[id] < contextRev) {
+      mapping[id] = contextRev;
+      await method();
+    }
+  });
+  onWillUnmount(() => {
+    ctx.off("update", component);
+    delete mapping[id];
+  });
+  return ctx.state;
+}

src/core/event_bus.ts

@@ -29,7 +29,7 @@ export class EventBus {
    * Add a listener for the 'eventType' events.
    *
    * Note that the 'owner' of this event can be anything, but will more likely
-   * be a widget or a class. The idea is that the callback will be called with
+   * be a component or a class. The idea is that the callback will be called with
    * the proper owner bound.
    *
    * Also, the owner should be kind of unique. This will be used to remove the

src/core/observer.ts

@@ -0,0 +1,109 @@
+/**
+ * Owl Observer
+ *
+ * This code contains the logic that allows Owl to observe and react to state
+ * changes.
+ *
+ * This is a Observer class that can observe any JS values.  The way it works
+ * can be summarized thusly:
+ * - primitive values are not observed at all
+ * - Objects and arrays are observed by replacing them with a Proxy
+ * - each object/array metadata are tracked in a weakmap, and keep a revision
+ *   number
+ *
+ * Note that this code is loosely inspired by Vue.
+ */
+
+//------------------------------------------------------------------------------
+// Observer
+//------------------------------------------------------------------------------
+export class Observer {
+  rev: number = 1;
+  allowMutations: boolean = true;
+  dirty: boolean = false;
+  weakMap: WeakMap<any, any> = new WeakMap();
+
+  notifyCB() {}
+  async notifyChange() {
+    this.dirty = true;
+    await Promise.resolve();
+    if (this.dirty) {
+      this.dirty = false;
+      this.notifyCB();
+    }
+  }
+
+  observe<T>(value: T, parent?: any): T {
+    if (value === null || typeof value !== "object" || value instanceof Date) {
+      // fun fact: typeof null === 'object'
+      return value;
+    }
+    let metadata = this.weakMap.get(value) || this._observe(value, parent);
+    return metadata.proxy;
+  }
+
+  revNumber(value): number {
+    const metadata = this.weakMap.get(value);
+    return metadata ? metadata.rev : 0;
+  }
+  deepRevNumber(value): number {
+    const metadata = this.weakMap.get(value);
+    return metadata ? metadata.deepRev : 0;
+  }
+
+  _observe(value, parent) {
+    var self = this;
+
+    const proxy = new Proxy(value, {
+      get(target, k) {
+        const targetValue = target[k];
+        return self.observe(targetValue, value);
+      },
+      set(target, key: string, newVal): boolean {
+        const value = target[key];
+        if (newVal !== value) {
+          if (!self.allowMutations) {
+            throw new Error(
+              `Observed state cannot be changed here! (key: "${key}", val: "${newVal}")`
+            );
+          }
+          self._updateRevNumber(target);
+          target[key] = newVal;
+          self.notifyChange();
+        }
+        return true;
+      },
+      deleteProperty(target, key) {
+        if (key in target) {
+          delete target[key];
+          self._updateRevNumber(target);
+          self.notifyChange();
+        }
+        return true;
+      }
+    });
+
+    const metadata = {
+      value,
+      proxy,
+      rev: this.rev,
+      deepRev: this.rev,
+      parent
+    };
+
+    this.weakMap.set(value, metadata);
+    this.weakMap.set(metadata.proxy, metadata);
+    return metadata;
+  }
+
+  _updateRevNumber(target: any) {
+    this.rev++;
+    let metadata = this.weakMap.get(target);
+    metadata.rev!++;
+    let parent = target;
+    do {
+      metadata = this.weakMap.get(parent);
+      metadata.deepRev++;
+    } while ((parent = metadata.parent) && parent !== target);
+  }
+}

src/hooks.ts

@@ -0,0 +1,128 @@
+import { Component } from "./component/component";
+import { Observer } from "./core/observer";
+
+/**
+ * Owl Hook System
+ *
+ * This file introduces the concept of hooks, similar to React or Vue hooks.
+ * We have currently an implementation of:
+ * - useState (reactive state)
+ * - onMounted
+ * - onWillUnmount
+ * - useRef
+ */
+
+// -----------------------------------------------------------------------------
+// useState
+// -----------------------------------------------------------------------------
+
+/**
+ * This is the main way a component can be made reactive.  The useState hook
+ * will return an observed object (or array).  Changes to that value will then
+ * trigger a rerendering of the current component.
+ */
+export function useState<T>(state: T): T {
+  const component: Component<any, any> = Component.current!;
+  const __owl__ = component.__owl__;
+  if (!__owl__.observer) {
+    __owl__.observer = new Observer();
+    __owl__.observer.notifyCB = component.render.bind(component);
+  }
+  return __owl__.observer.observe(state);
+}
+
+// -----------------------------------------------------------------------------
+// Life cycle hooks
+// -----------------------------------------------------------------------------
+function makeLifecycleHook(method: string, reverse: boolean = false) {
+  if (reverse) {
+    return function(cb) {
+      const component: Component<any, any> = Component.current!;
+      if (component.__owl__[method]) {
+        const current = component.__owl__[method];
+        component.__owl__[method] = function() {
+          current.call(component);
+          cb.call(component);
+        };
+      } else {
+        component.__owl__[method] = cb;
+      }
+    };
+  } else {
+    return function(cb) {
+      const component: Component<any, any> = Component.current!;
+      if (component.__owl__[method]) {
+        const current = component.__owl__[method];
+        component.__owl__[method] = function() {
+          cb.call(component);
+          current.call(component);
+        };
+      } else {
+        component.__owl__[method] = cb;
+      }
+    };
+  }
+}
+
+function makeAsyncHook(method: string) {
+  return function(cb) {
+    const component: Component<any, any> = Component.current!;
+    if (component.__owl__[method]) {
+      const current = component.__owl__[method];
+      component.__owl__[method] = function(...args) {
+        return Promise.all[(current.call(component, ...args), cb.call(component, ...args))];
+      };
+    } else {
+      component.__owl__[method] = cb;
+    }
+  };
+}
+
+export const onMounted = makeLifecycleHook("mountedCB", true);
+export const onWillUnmount = makeLifecycleHook("willUnmountCB");
+export const onWillPatch = makeLifecycleHook("willPatchCB");
+export const onPatched = makeLifecycleHook("patchedCB", true);
+
+export const onWillStart = makeAsyncHook("willStartCB");
+export const onWillUpdateProps = makeAsyncHook("willUpdatePropsCB");
+
+// -----------------------------------------------------------------------------
+// useRef
+// -----------------------------------------------------------------------------
+
+/**
+ * The purpose of this hook is to allow components to get a reference to a sub
+ * html node or component.
+ */
+interface Ref {
+  el: HTMLElement | null;
+  comp: Component<any, any> | null;
+}
+
+export function useRef(name: string): Ref {
+  const __owl__ = Component.current!.__owl__;
+  return {
+    get el(): HTMLElement | null {
+      const val = __owl__.refs && __owl__.refs[name];
+      return val instanceof HTMLElement ? val : null;
+    },
+    get comp(): Component<any, any> | null {
+      const val = __owl__.refs && __owl__.refs[name];
+      return val instanceof Component ? val : null;
+    }
+  };
+}
+
+// -----------------------------------------------------------------------------
+// useSubEnv
+// -----------------------------------------------------------------------------
+
+/**
+ * This hook is a simple way to let components use a sub environment.  Note that
+ * like for all hooks, it is important that this is only called in the
+ * constructor method.
+ */
+export function useSubEnv(nextEnv) {
+  const component = Component.current!;
+  component.env = Object.assign(Object.create(component.env), nextEnv);
+}

src/index.ts

@@ -4,20 +4,36 @@
  *
  * Note that dynamic values, such as a date or a commit hash are added by rollup
  */
-export { Component } from "./component";
-export { EventBus } from "./event_bus";
-export { Observer } from "./observer";
+import { EventBus } from "./core/event_bus";
+import { Observer } from "./core/observer";
+import { QWeb } from "./qweb/index";
+import * as _store from "./store";
+import * as _utils from "./utils";
+import * as _tags from "./tags";
+import {AsyncRoot} from "./misc/async_root";
+import * as _hooks from "./hooks";
+import * as _context from "./context";
+import { Link } from "./router/link";
+import { RouteComponent } from "./router/route_component";
+import { Router } from "./router/router";
 
-// we need to import manually the extra directives so they can register
-// themselves in QWeb, otherwise these files will not even be loaded.
-import "./qweb_directives";
-import "./qweb_extensions";
-import { QWeb } from "./qweb_core";
+export { Component } from "./component/component";
 export { QWeb };
 
-export { connect, Store } from "./store";
-import * as _utils from "./utils";
-
+export const Context = _context.Context;
+export const useState = _hooks.useState;
+export const core = { EventBus, Observer };
+export const router = { Router, RouteComponent, Link };
+export const Store = _store.Store;
+export const utils = _utils;
+export const tags = _tags;
+export const misc = { AsyncRoot};
+export const hooks = Object.assign({}, _hooks, {
+  useContext: _context.useContext,
+  useDispatch: _store.useDispatch,
+  useGetters: _store.useGetters,
+  useStore: _store.useStore
+});
 export const __info__ = {};
 
 Object.defineProperty(__info__, "mode", {
@@ -32,8 +48,7 @@ Object.defineProperty(__info__, "mode", {
         `Owl is running in 'dev' mode.  This is not suitable for production use. See ${url} for more information.`
       );
     } else {
-        console.log(`Owl is now running in 'prod' mode.`)
+      console.log(`Owl is now running in 'prod' mode.`);
     }
   }
 });
-export const utils = _utils;

src/misc/async_root.ts

@@ -0,0 +1,19 @@
+import { Component } from "../component/component";
+import { xml } from "../tags";
+
+/**
+ * AsyncRoot
+ *
+ * Owl is by default asynchronous, and the user interface will wait for all its
+ * subcomponents to be rendered before updating the DOM. This is most of the
+ * time what we want, but in some cases, it makes sense to "detach" a component
+ * from this coordination.  This is the goal of the AsyncRoot component.
+ */
+
+export class AsyncRoot extends Component<any, any> {
+  static template = xml`<t t-slot="default"/>`;
+
+  async __updateProps(nextProps, parentFiber) {
+    this.render(parentFiber.force);
+  }
+}

src/observer.ts

@@ -1,211 +0,0 @@
-/**
- * Owl Observer
- *
- * This code contains the logic that allows Owl to observe and react to state
- * changes.
- *
- * This is a Observer class that can observe any JS values.  The way it works
- * can be summarized thusly:
- * - primitive values are not observed at all
- * - Objects are observed by replacing all their keys with getters/setters
- *   (recursively)
- * - Arrays are observed by replacing their prototype with a customized version,
- *   which wrap some methods to allow the tracking of each state change.
- *
- * Note that this code is inspired by Vue.
- */
-
-//------------------------------------------------------------------------------
-// Modified Array prototype
-//------------------------------------------------------------------------------
-
-// we define here a new modified Array prototype, which basically override all
-// Array methods that change some state to be able to track their changes
-const methodsToPatch = [
-  "push",
-  "pop",
-  "shift",
-  "unshift",
-  "splice",
-  "sort",
-  "reverse"
-];
-const methodLen = methodsToPatch.length;
-
-const ArrayProto = Array.prototype;
-const ModifiedArrayProto = Object.create(ArrayProto);
-
-for (let i = 0; i < methodLen; i++) {
-  const method = methodsToPatch[i];
-  const initialMethod = ArrayProto[method];
-  ModifiedArrayProto[method] = function(...args) {
-    if (!this.__observer__.allowMutations) {
-      throw new Error(`Array cannot be changed here")`);
-    }
-    this.__observer__.rev++;
-    this.__observer__.notifyChange();
-    this.__owl__.rev++;
-    let parent = this;
-    do {
-      parent.__owl__.deepRev++;
-    } while ((parent = parent.__owl__.parent));
-    let inserted;
-    switch (method) {
-      case "push":
-      case "unshift":
-        inserted = args;
-        break;
-      case "splice":
-        inserted = args.slice(2);
-        break;
-    }
-    if (inserted) {
-      for (let i = 0, iLen = inserted.length; i < iLen; i++) {
-        this.__observer__.observe(inserted[i], this);
-      }
-    }
-    return initialMethod.call(this, ...args);
-  };
-}
-
-//------------------------------------------------------------------------------
-// Observer
-//------------------------------------------------------------------------------
-export class Observer {
-  rev: number = 1;
-  allowMutations: boolean = true;
-  dirty: boolean = false;
-
-  static set(target: any, key: number | string, value: any) {
-    if (!target.__owl__) {
-      throw Error(
-        "`Observer.set()` can only be called with observed Objects or Arrays"
-      );
-    }
-    target.__owl__.observer.set(target, key, value);
-  }
-
-  static delete(target: any, key: number | string) {
-    if (!target.__owl__) {
-      throw Error(
-        "`Observer.delete()` can only be called with observed Objects"
-      );
-    }
-    target.__owl__.observer.delete(target, key);
-  }
-
-  notifyCB() {}
-  notifyChange() {
-    this.dirty = true;
-    Promise.resolve().then(() => {
-      if (this.dirty) {
-        this.dirty = false;
-        this.notifyCB();
-      }
-    });
-  }
-
-  observe(value: any, parent?: any) {
-    if (value === null) {
-      // fun fact: typeof null === 'object'
-      return;
-    }
-    if (typeof value !== "object") {
-      return;
-    }
-    if ("__owl__" in value) {
-      // already observed
-      value.__owl__.parent = parent;
-      return;
-    }
-    if (Array.isArray(value)) {
-      this._observeArr(value, parent);
-    } else {
-      this._observeObj(value, parent);
-    }
-  }
-
-  set(target: any, key: number | string, value: any) {
-    let alreadyDefined =
-      key in target &&
-      Object.getOwnPropertyDescriptor(target, key)!.configurable === false;
-    if (alreadyDefined) {
-      target[key] = value;
-    } else {
-      this._addProp(target, key, value);
-      this._updateRevNumber(target);
-    }
-    this.notifyChange();
-  }
-
-  delete(target: any, key: number | string) {
-    delete target[key];
-    this._updateRevNumber(target);
-    this.notifyChange();
-  }
-
-  _observeObj<T extends { __owl__?: any }>(obj: T, parent?: any) {
-    obj.__owl__ = {
-      rev: this.rev,
-      deepRev: this.rev,
-      parent,
-      observer: this
-    };
-    Object.defineProperty(obj, "__owl__", { enumerable: false });
-    for (let key in obj) {
-      this._addProp(obj, key, obj[key]);
-    }
-  }
-
-  _observeArr(arr: Array<any>, parent?: any) {
-    (<any>arr).__owl__ = {
-      rev: this.rev,
-      deepRev: this.rev,
-      parent,
-      observer: this
-    };
-    Object.defineProperty(arr, "__owl__", { enumerable: false });
-    (<any>arr).__proto__ = Object.create(ModifiedArrayProto);
-    (<any>arr).__proto__.__observer__ = this;
-    for (let i = 0, iLen = arr.length; i < iLen; i++) {
-      this.observe(arr[i], arr);
-    }
-  }
-
-  _addProp<T extends { __owl__?: any }>(
-    obj: T,
-    key: string | number,
-    value: any
-  ) {
-    var self = this;
-    Object.defineProperty(obj, key, {
-      configurable: true,
-      enumerable: true,
-      get() {
-        return value;
-      },
-      set(newVal) {
-        if (newVal !== value) {
-          if (!self.allowMutations) {
-            throw new Error(
-              `Observed state cannot be changed here! (key: "${key}", val: "${newVal}")`
-            );
-          }
-          self._updateRevNumber(obj);
-          value = newVal;
-          self.observe(newVal, obj);
-          self.notifyChange();
-        }
-      }
-    });
-    this.observe(value, obj);
-  }
-  _updateRevNumber(target: any) {
-    this.rev++;
-    target.__owl__.rev!++;
-    let parent = target;
-    do {
-      parent.__owl__.deepRev++;
-    } while ((parent = parent.__owl__.parent) && parent !== target);
-  }
-}

src/qweb/base_directives.ts

@@ -1,5 +1,7 @@
-import { Context, QWeb, UTILS } from "./qweb_core";
-import { QWebExprVar } from "./qweb_expressions";
+import { CompilationContext } from "./compilation_context";
+import { QWebExprVar } from "./expression_parser";
+import { QWeb } from "./qweb";
+import { htmlToVDOM } from "../vdom/html_to_vdom";
 
 /**
  * Owl QWeb Directives
@@ -18,13 +20,15 @@ import { QWebExprVar } from "./qweb_expressions";
 //------------------------------------------------------------------------------
 // t-esc and t-raw
 //------------------------------------------------------------------------------
-(<any>UTILS).getFragment = function(str: string): DocumentFragment {
+QWeb.utils.getFragment = function(str: string): DocumentFragment {
   const temp = document.createElement("template");
   temp.innerHTML = str;
   return temp.content;
 };
 
-function compileValueNode(value: any, node: Element, qweb: QWeb, ctx: Context) {
+QWeb.utils.htmlToVDOM = htmlToVDOM;
+
+function compileValueNode(value: any, node: Element, qweb: QWeb, ctx: CompilationContext) {
   if (value === "0" && ctx.caller) {
     qweb._compileNode(ctx.caller, ctx);
     return;
@@ -54,18 +58,13 @@ function compileValueNode(value: any, node: Element, qweb: QWeb, ctx: Context) {
       ctx.rootContext.rootNode = nodeID;
       ctx.rootContext.parentTextNode = nodeID;
       ctx.addLine(`var vn${nodeID} = {text: ${exprID}};`);
+      if (ctx.rootContext.shouldDefineResult) {
+        ctx.addLine(`result = vn${nodeID}`);
+      }
     }
   } else {
-    let fragID = ctx.generateID();
-    ctx.addLine(`var frag${fragID} = this.utils.getFragment(${exprID})`);
-    let tempNodeID = ctx.generateID();
-    ctx.addLine(`var p${tempNodeID} = {hook: {`);
-    ctx.addLine(
-      `  insert: n => n.elm.parentNode.replaceChild(frag${fragID}, n.elm),`
-    );
-    ctx.addLine(`}};`);
-    ctx.addLine(`var vn${tempNodeID} = h('div', p${tempNodeID})`);
-    ctx.addLine(`c${ctx.parentNode}.push(vn${tempNodeID});`);
+    ctx.rootContext.shouldDefineUtils = true;
+    ctx.addLine(`c${ctx.parentNode}.push(...utils.htmlToVDOM(${exprID}));`);
   }
   if (node.childNodes.length) {
     ctx.addElse();
@@ -79,10 +78,6 @@ QWeb.addDirective({
   name: "esc",
   priority: 70,
   atNodeEncounter({ node, qweb, ctx }): boolean {
-    if (node.nodeName !== "t") {
-      let nodeID = qweb._compileGenericNode(node, ctx);
-      ctx = ctx.withParent(nodeID);
-    }
     let value = ctx.getValue(node.getAttribute("t-esc")!);
     compileValueNode(value, node, qweb, ctx.subContext("escaping", true));
     return true;
@@ -93,10 +88,6 @@ QWeb.addDirective({
   name: "raw",
   priority: 80,
   atNodeEncounter({ node, qweb, ctx }): boolean {
-    if (node.nodeName !== "t") {
-      let nodeID = qweb._compileGenericNode(node, ctx);
-      ctx = ctx.withParent(nodeID);
-    }
     let value = ctx.getValue(node.getAttribute("t-raw")!);
     compileValueNode(value, node, qweb, ctx);
     return true;
@@ -116,9 +107,7 @@ QWeb.addDirective({
     if (value) {
       const formattedValue = ctx.formatExpression(value);
       if (ctx.variables.hasOwnProperty(variable)) {
-        ctx.addLine(
-          `${(<QWebExprVar>ctx.variables[variable]).id} = ${formattedValue}`
-        );
+        ctx.addLine(`${(<QWebExprVar>ctx.variables[variable]).id} = ${formattedValue}`);
       } else {
         const varName = `_${ctx.generateID()}`;
         ctx.addLine(`var ${varName} = ${formattedValue};`);
@@ -144,7 +133,7 @@ QWeb.addDirective({
   priority: 20,
   atNodeEncounter({ node, ctx }): boolean {
     let cond = ctx.getValue(node.getAttribute("t-if")!);
-    ctx.addIf(`${ctx.formatExpression(cond)}`);
+    ctx.addIf(typeof cond === "string" ? ctx.formatExpression(cond) : cond.id);
     return false;
   },
   finalize({ ctx }) {
@@ -157,7 +146,7 @@ QWeb.addDirective({
   priority: 30,
   atNodeEncounter({ node, ctx }): boolean {
     let cond = ctx.getValue(node.getAttribute("t-elif")!);
-    ctx.addLine(`else if (${ctx.formatExpression(cond)}) {`);
+    ctx.addLine(`else if (${typeof cond === "string" ? ctx.formatExpression(cond) : cond.id}) {`);
     ctx.indent();
     return false;
   },
@@ -198,14 +187,57 @@ QWeb.addDirective({
     nodeCopy.removeAttribute("t-call");
 
     // extract variables from nodecopy
-    const tempCtx = new Context();
+    const tempCtx = new CompilationContext();
     tempCtx.nextID = ctx.rootContext.nextID;
+    tempCtx.allowMultipleRoots = true;
     qweb._compileNode(nodeCopy, tempCtx);
     const vars = Object.assign({}, ctx.variables, tempCtx.variables);
     ctx.rootContext.nextID = tempCtx.nextID;
 
+    const templateMap = Object.create(ctx.templates);
     // open new scope, if necessary
     const hasNewVariables = Object.keys(tempCtx.variables).length > 0;
+
+    // compile sub template
+    let subCtx = ctx.subContext("caller", nodeCopy).subContext("variables", Object.create(vars));
+    subCtx = subCtx.subContext("templates", templateMap);
+
+    if (templateMap[subTemplate]) {
+      // OUCH, IT IS A RECURSIVE TEMPLATE SITUATION...
+      // This is a tricky situation... We obviously cannot inline the compiled
+      // template. So, what we need to do is to compile it, and make sure we
+      // properly transfer everything from the current scope to the sub template.
+      ctx.rootContext.shouldTrackScope = true;
+      ctx.rootContext.shouldDefineOwner = true;
+      let subTemplateName;
+      if (ctx.hasParentWidget) {
+        subTemplateName = ctx.templateName;
+      } else {
+        subTemplateName = `__${ctx.generateID()}`;
+        subCtx.variables = {};
+        let id = 0;
+        for (let v in vars) {
+          subCtx.variables[v] = vars[v];
+          (vars[v] as any).id = `_v${id++}`;
+        }
+        const subTemplateFn = qweb._compile(subTemplateName, nodeTemplate.elem, subCtx);
+        qweb.recursiveFns[subTemplateName] = subTemplateFn;
+      }
+      let varCode = `{}`;
+      if (Object.keys(vars).length) {
+        let id = 0;
+        const content = Object.values(vars)
+          .map((v: any) => `_v${id++}: ${v.expr}`)
+          .join(",");
+        varCode = `{${content}}`;
+      }
+      ctx.addLine(
+        `this.recursiveFns['${subTemplateName}'].call(this, context, Object.assign({}, extra, {parentNode: c${ctx.parentNode}, fiber: {vars: ${varCode}, scope}}));`
+      );
+      return true;
+    }
+    templateMap[subTemplate] = true;
+
     if (hasNewVariables) {
       ctx.addLine("{");
       ctx.indent();
@@ -218,12 +250,6 @@ QWeb.addDirective({
         // todo: handle XML variables...
       }
     }
-
-    // compile sub template
-    const subCtx = ctx
-      .subContext("caller", nodeCopy)
-      .subContext("variables", Object.create(vars));
-
     qweb._compileNode(nodeTemplate.elem, subCtx);
 
     // close new scope
@@ -245,14 +271,12 @@ QWeb.addDirective({
   priority: 10,
   atNodeEncounter({ node, qweb, ctx }): boolean {
     ctx.rootContext.shouldProtectContext = true;
-    ctx = ctx.subContext("inLoop", true);
+    ctx = ctx.subContext("loopNumber", ctx.loopNumber + 1);
     const elems = node.getAttribute("t-foreach")!;
     const name = node.getAttribute("t-as")!;
     let arrayID = ctx.generateID();
     ctx.addLine(`var _${arrayID} = ${ctx.formatExpression(elems)};`);
-    ctx.addLine(
-      `if (!_${arrayID}) { throw new Error('QWeb error: Invalid loop expression')}`
-    );
+    ctx.addLine(`if (!_${arrayID}) { throw new Error('QWeb error: Invalid loop expression')}`);
     let keysID = ctx.generateID();
     let valuesID = ctx.generateID();
     ctx.addLine(`var _${keysID} = _${valuesID} = _${arrayID};`);
@@ -261,18 +285,18 @@ QWeb.addDirective({
     ctx.addLine(`_${valuesID} = Object.values(_${arrayID});`);
     ctx.closeIf();
     ctx.addLine(`var _length${keysID} = _${keysID}.length;`);
-    ctx.addLine(`for (let i = 0; i < _length${keysID}; i++) {`);
+    const loopVar = `i${ctx.loopNumber}`;
+    ctx.addLine(`for (let ${loopVar} = 0; ${loopVar} < _length${keysID}; ${loopVar}++) {`);
     ctx.indent();
-    ctx.addLine(`context.${name}_first = i === 0;`);
-    ctx.addLine(`context.${name}_last = i === _length${keysID} - 1;`);
-    ctx.addLine(`context.${name}_index = i;`);
-    ctx.addLine(`context.${name} = _${keysID}[i];`);
-    ctx.addLine(`context.${name}_value = _${valuesID}[i];`);
+    ctx.addToScope(name + "_first", `${loopVar} === 0`);
+    ctx.addToScope(name + "_last", `${loopVar} === _length${keysID} - 1`);
+    ctx.addToScope(name + "_index", loopVar);
+    ctx.addToScope(name, `_${keysID}[${loopVar}]`);
+    ctx.addToScope(name + "_value", `_${valuesID}[${loopVar}]`);
     const nodeCopy = <Element>node.cloneNode(true);
-    let shouldWarn =
-      nodeCopy.tagName !== "t" && !nodeCopy.hasAttribute("t-key");
+    let shouldWarn = nodeCopy.tagName !== "t" && !nodeCopy.hasAttribute("t-key");
     if (!shouldWarn && node.tagName === "t") {
-      if (node.hasAttribute("t-widget") && !node.hasAttribute("t-key")) {
+      if (node.hasAttribute("t-component") && !node.hasAttribute("t-key")) {
         shouldWarn = true;
       }
       if (
@@ -286,9 +310,7 @@ QWeb.addDirective({
     }
     if (shouldWarn) {
       console.warn(
-        `Directive t-foreach should always be used with a t-key! (in template: '${
-          ctx.templateName
-        }')`
+        `Directive t-foreach should always be used with a t-key! (in template: '${ctx.templateName}')`
       );
     }
     nodeCopy.removeAttribute("t-foreach");
@@ -304,7 +326,7 @@ QWeb.addDirective({
 //------------------------------------------------------------------------------
 QWeb.addDirective({
   name: "debug",
-  priority: 99,
+  priority: 1,
   atNodeEncounter({ ctx }) {
     ctx.addLine("debugger;");
   }
@@ -315,7 +337,7 @@ QWeb.addDirective({
 //------------------------------------------------------------------------------
 QWeb.addDirective({
   name: "log",
-  priority: 99,
+  priority: 1,
   atNodeEncounter({ ctx, value }) {
     const expr = ctx.formatExpression(value);
     ctx.addLine(`console.log(${expr})`);

src/qweb/compilation_context.ts

@@ -0,0 +1,183 @@
+import { compileExpr, QWebVar, QWebExprVar } from "./expression_parser";
+
+export const INTERP_REGEXP = /\{\{.*?\}\}/g;
+//------------------------------------------------------------------------------
+// Compilation Context
+//------------------------------------------------------------------------------
+
+export class CompilationContext {
+  nextID: number = 1;
+  code: string[] = [];
+  variables: { [key: string]: QWebVar } = {};
+  escaping: boolean = false;
+  parentNode: number | null = null;
+  parentTextNode: number | null = null;
+  rootNode: number | null = null;
+  indentLevel: number = 0;
+  rootContext: CompilationContext;
+  caller: Element | undefined;
+  shouldDefineOwner: boolean = false;
+  shouldDefineParent: boolean = false;
+  shouldDefineQWeb: boolean = false;
+  shouldDefineUtils: boolean = false;
+  shouldDefineRefs: boolean = false;
+  shouldDefineResult: boolean = true;
+  shouldDefineSibling: boolean = true;
+  shouldProtectContext: boolean = false;
+  shouldTrackScope: boolean = false;
+  loopNumber: number = 0;
+  inPreTag: boolean = false;
+  templateName: string;
+  allowMultipleRoots: boolean = false;
+  hasParentWidget: boolean = false;
+  scopeVars: any[] = [];
+  currentKey: string = "";
+  lastNodeKey: string = ""; // temp variable to communicate to previous caller
+  templates: { [key: string]: boolean } = {};
+
+  constructor(name?: string) {
+    this.rootContext = this;
+    this.templateName = name || "noname";
+    this.templates[this.templateName] = true;
+    this.addLine("var h = this.h;");
+  }
+
+  generateID(): number {
+    const id = this.rootContext.nextID++;
+    return id;
+  }
+
+  generateCode(): string[] {
+    const shouldTrackScope = this.shouldTrackScope && this.scopeVars.length;
+    if (shouldTrackScope) {
+      // add some vars to scope if needed
+      for (let scopeVar of this.scopeVars.reverse()) {
+        let { index, key, indent } = scopeVar;
+        const prefix = new Array(indent + 2).join("    ");
+        this.code.splice(index + 1, 0, prefix + `scope.${key} = context.${key};`);
+      }
+      this.code.unshift("    const scope = Object.create(null);");
+    }
+    if (this.shouldProtectContext) {
+      this.code.unshift("    context = Object.create(context);");
+    }
+    if (this.shouldDefineResult) {
+      this.code.unshift("    let result;");
+    }
+    if (this.shouldDefineSibling) {
+      this.code.unshift("    let sibling = null;");
+    }
+    if (this.shouldDefineRefs) {
+      this.code.unshift("    context.__owl__.refs = context.__owl__.refs || {};");
+    }
+    if (this.shouldDefineOwner) {
+      // this is necessary to prevent some directives (t-forach for ex) to
+      // pollute the rendering context by adding some keys in it.
+      this.code.unshift("    let owner = context;");
+    }
+    if (this.shouldDefineParent) {
+      if (this.hasParentWidget) {
+        this.code.unshift("    let parent = extra.parent;");
+      } else {
+        this.code.unshift("    let parent = context;");
+      }
+    }
+    if (this.shouldDefineQWeb) {
+      this.code.unshift("    let QWeb = this.constructor;");
+    }
+    if (this.shouldDefineUtils) {
+      this.code.unshift("    let utils = this.constructor.utils;");
+    }
+    return this.code;
+  }
+
+  withParent(node: number): CompilationContext {
+    if (
+      !this.allowMultipleRoots &&
+      this === this.rootContext &&
+      (this.parentNode || this.parentTextNode)
+    ) {
+      throw new Error("A template should not have more than one root node");
+    }
+    if (!this.rootContext.rootNode) {
+      this.rootContext.rootNode = node;
+    }
+    if (!this.parentNode && this.rootContext.shouldDefineResult) {
+      this.addLine(`result = vn${node};`);
+    }
+    return this.subContext("parentNode", node);
+  }
+
+  subContext(key: keyof CompilationContext, value: any): CompilationContext {
+    const newContext = Object.create(this);
+    newContext[key] = value;
+    return newContext;
+  }
+
+  indent() {
+    this.indentLevel++;
+  }
+
+  dedent() {
+    this.indentLevel--;
+  }
+
+  addLine(line: string): number {
+    const prefix = new Array(this.indentLevel + 2).join("    ");
+    this.code.push(prefix + line);
+    return this.code.length - 1;
+  }
+
+  addToScope(key: string, expr: string) {
+    const index = this.addLine(`context.${key} = ${expr};`);
+    this.rootContext.scopeVars.push({ index, key, indent: this.indentLevel });
+  }
+
+  addIf(condition: string) {
+    this.addLine(`if (${condition}) {`);
+    this.indent();
+  }
+
+  addElse() {
+    this.dedent();
+    this.addLine("} else {");
+    this.indent();
+  }
+
+  closeIf() {
+    this.dedent();
+    this.addLine("}");
+  }
+
+  getValue(val: any): QWebExprVar | string {
+    return val in this.variables ? this.getValue(this.variables[val]) : val;
+  }
+
+  /**
+   * Prepare an expression for being consumed at render time.  Its main job
+   * is to
+   * - replace unknown variables by a lookup in the context
+   * - replace already defined variables by their internal name
+   */
+  formatExpression(expr: string): string {
+    return compileExpr(expr, this.variables);
+  }
+
+  /**
+   * Perform string interpolation on the given string. Note that if the whole
+   * string is an expression, it simply returns it (formatted and enclosed in
+   * parentheses).
+   * For instance:
+   *   'Hello {{x}}!' -> `Hello ${x}`
+   *   '{{x ? 'a': 'b'}}' -> (x ? 'a' : 'b')
+   */
+  interpolate(s: string): string {
+    let matches = s.match(INTERP_REGEXP);
+    if (matches && matches[0].length === s.length) {
+      return `(${this.formatExpression(s.slice(2, -2))})`;
+    }
+
+    let r = s.replace(/\{\{.*?\}\}/g, s => "${" + this.formatExpression(s.slice(2, -2)) + "}");
+    return "`" + r + "`";
+  }
+}

src/qweb/expression_parser.ts

@@ -82,7 +82,7 @@ const STATIC_TOKEN_MAP: { [key: string]: TKind } = {
   ")": "RIGHT_PAREN"
 };
 
-const OPERATORS = ".,===,==,+,!,||,&&,>=,>,<=,<,?,-,*,/,%".split(',');
+const OPERATORS = ".,===,==,+,!==,!=,!,||,&&,>=,>,<=,<,?,-,*,/,%".split(",");
 
 type Tokenizer = (expr: string) => Token | false;
 
@@ -231,10 +231,7 @@ export function tokenize(expr: string): Token[] {
  * - or if the previous token is a left brace or a comma, and the next token is
  *   a colon (in that case, this is an object key: `{a: b}`)
  */
-export function compileExpr(
-  expr: string,
-  vars: { [key: string]: QWebVar }
-): string {
+export function compileExpr(expr: string, vars: { [key: string]: QWebVar }): string {
   const tokens = tokenize(expr);
   let result = "";
   for (let i = 0; i < tokens.length; i++) {
@@ -246,10 +243,7 @@ export function compileExpr(
       if (prevToken) {
         if (prevToken.type === "OPERATOR" && prevToken.value === ".") {
           isVar = false;
-        } else if (
-          prevToken.type === "LEFT_BRACE" ||
-          prevToken.type === "COMMA"
-        ) {
+        } else if (prevToken.type === "LEFT_BRACE" || prevToken.type === "COMMA") {
           let nextToken = tokens[i + 1];
           if (nextToken && nextToken.type === "COLON") {
             isVar = false;

src/qweb/extensions.ts

@@ -0,0 +1,261 @@
+import { VNode } from "../vdom/index";
+import { QWeb } from "./qweb";
+
+/**
+ * Owl QWeb Extensions
+ *
+ * This file contains the implementation of non standard QWeb directives, added
+ * by Owl and that will only work on Owl projects:
+ *
+ * - t-on
+ * - t-ref
+ * - t-transition
+ * - t-mounted
+ * - t-slot
+ * - t-model
+ */
+
+//------------------------------------------------------------------------------
+// t-on
+//------------------------------------------------------------------------------
+// these are pieces of code that will be injected into the event handler if
+// modifiers are specified
+export const MODS_CODE = {
+  prevent: "e.preventDefault();",
+  self: "if (e.target !== this.elm) {return}",
+  stop: "e.stopPropagation();"
+};
+
+QWeb.addDirective({
+  name: "on",
+  priority: 90,
+  atNodeCreation({ ctx, fullName, value, nodeID }) {
+    ctx.rootContext.shouldDefineOwner = true;
+    const [eventName, ...mods] = fullName.slice(5).split(".");
+    if (!eventName) {
+      throw new Error("Missing event name with t-on directive");
+    }
+    let extraArgs;
+    let handlerName = value.replace(/\(.*\)/, function(args) {
+      extraArgs = args.slice(1, -1);
+      return "";
+    });
+    let params = extraArgs ? `owner, ${ctx.formatExpression(extraArgs)}` : "owner";
+    let handler = `function (e) {`;
+    handler += mods
+      .map(function(mod) {
+        return MODS_CODE[mod];
+      })
+      .join("");
+    if (handlerName) {
+      if (!extraArgs) {
+        handler += `const fn = context['${handlerName}'];`;
+        handler += `if (fn) { fn.call(${params}, e); } else { context.${handlerName}; }`;
+        handler += `}`;
+        ctx.addLine(
+          `extra.handlers['${eventName}' + ${nodeID}] = extra.handlers['${eventName}' + ${nodeID}] || ${handler};`
+        );
+        ctx.addLine(`p${nodeID}.on['${eventName}'] = extra.handlers['${eventName}' + ${nodeID}];`);
+      } else {
+        const handlerKey = `handler${ctx.generateID()}`;
+        ctx.addLine(`const ${handlerKey} = context['${handlerName}'] && context['${handlerName}'].bind(${params});`);
+        handler += `if (${handlerKey}) { ${handlerKey}(e); } else { context.${value}; }`;
+        handler += `}`;
+        ctx.addLine(`p${nodeID}.on['${eventName}'] = ${handler};`);
+      }
+    } else {
+      handler += "}";
+      ctx.addLine(`p${nodeID}.on['${eventName}'] = ${handler};`);
+    }
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-ref
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "ref",
+  priority: 95,
+  atNodeCreation({ ctx, value, addNodeHook }) {
+    ctx.rootContext.shouldDefineRefs = true;
+    const refKey = `ref${ctx.generateID()}`;
+    ctx.addLine(`const ${refKey} = ${ctx.interpolate(value)};`);
+    addNodeHook("create", `context.__owl__.refs[${refKey}] = n.elm;`);
+    addNodeHook("destroy", `delete context.__owl__.refs[${refKey}];`);
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-transition
+//------------------------------------------------------------------------------
+QWeb.utils.nextFrame = function(cb: () => void) {
+  requestAnimationFrame(() => requestAnimationFrame(cb));
+};
+
+QWeb.utils.transitionInsert = function(vn: VNode, name: string) {
+  const elm = <HTMLElement>vn.elm;
+  // remove potential duplicated vnode that is currently being removed, to
+  // prevent from having twice the same node in the DOM during an animation
+  const dup = elm.parentElement && elm.parentElement!.querySelector(`*[data-owl-key='${vn.key}']`);
+  if (dup) {
+    dup.remove();
+  }
+
+  elm.classList.add(name + "-enter");
+  elm.classList.add(name + "-enter-active");
+  const finalize = () => {
+    elm.classList.remove(name + "-enter-active");
+    elm.classList.remove(name + "-enter-to");
+  };
+  this.nextFrame(() => {
+    elm.classList.remove(name + "-enter");
+    elm.classList.add(name + "-enter-to");
+    whenTransitionEnd(elm, finalize);
+  });
+};
+
+QWeb.utils.transitionRemove = function(vn: VNode, name: string, rm: () => void) {
+  const elm = <HTMLElement>vn.elm;
+  elm.setAttribute("data-owl-key", vn.key!);
+
+  elm.classList.add(name + "-leave");
+  elm.classList.add(name + "-leave-active");
+  const finalize = () => {
+    elm.classList.remove(name + "-leave-active");
+    elm.classList.remove(name + "-leave-to");
+    rm();
+  };
+  this.nextFrame(() => {
+    elm.classList.remove(name + "-leave");
+    elm.classList.add(name + "-leave-to");
+    whenTransitionEnd(elm, finalize);
+  });
+};
+
+function getTimeout(delays: Array<string>, durations: Array<string>): number {
+  /* istanbul ignore next */
+  while (delays.length < durations.length) {
+    delays = delays.concat(delays);
+  }
+
+  return Math.max.apply(
+    null,
+    durations.map((d, i) => {
+      return toMs(d) + toMs(delays[i]);
+    })
+  );
+}
+
+// Old versions of Chromium (below 61.0.3163.100) formats floating pointer numbers
+// in a locale-dependent way, using a comma instead of a dot.
+// If comma is not replaced with a dot, the input will be rounded down (i.e. acting
+// as a floor function) causing unexpected behaviors
+function toMs(s: string): number {
+  return Number(s.slice(0, -1).replace(",", ".")) * 1000;
+}
+
+function whenTransitionEnd(elm: HTMLElement, cb) {
+  const styles = window.getComputedStyle(elm);
+  const delays: Array<string> = (styles.transitionDelay || "").split(", ");
+  const durations: Array<string> = (styles.transitionDuration || "").split(", ");
+  const timeout: number = getTimeout(delays, durations);
+  if (timeout > 0) {
+    elm.addEventListener("transitionend", cb, { once: true });
+  } else {
+    cb();
+  }
+}
+
+QWeb.addDirective({
+  name: "transition",
+  priority: 96,
+  atNodeCreation({ ctx, value, addNodeHook }) {
+    ctx.rootContext.shouldDefineUtils = true;
+    let name = value;
+    const hooks = {
+      insert: `utils.transitionInsert(vn, '${name}');`,
+      remove: `utils.transitionRemove(vn, '${name}', rm);`
+    };
+    for (let hookName in hooks) {
+      addNodeHook(hookName, hooks[hookName]);
+    }
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-slot
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "slot",
+  priority: 80,
+  atNodeEncounter({ ctx, value }): boolean {
+    const slotKey = ctx.generateID();
+    ctx.rootContext.shouldDefineOwner = true;
+    ctx.addLine(
+      `const slot${slotKey} = this.constructor.slots[context.__owl__.slotId + '_' + '${value}'];`
+    );
+    ctx.addIf(`slot${slotKey}`);
+    let parentNode = `c${ctx.parentNode}`;
+    if (!ctx.parentNode) {
+      ctx.rootContext.shouldDefineResult = true;
+      ctx.rootContext.shouldDefineUtils = true;
+      parentNode = `children${ctx.nextID++}`;
+      ctx.addLine(`let ${parentNode}= []`);
+      ctx.addLine(`result = {}`);
+    }
+    ctx.addLine(
+      `slot${slotKey}.call(this, context.__owl__.parent, Object.assign({}, extra, {parentNode: ${parentNode}, vars: extra.vars, parent: owner}));`
+    );
+    if (!ctx.parentNode) {
+      ctx.addLine(`utils.defineProxy(result, ${parentNode}[0]);`);
+    }
+    ctx.closeIf();
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-model
+//------------------------------------------------------------------------------
+QWeb.utils.toNumber = function(val: string): number | string {
+  const n = parseFloat(val);
+  return isNaN(n) ? val : n;
+};
+
+QWeb.addDirective({
+  name: "model",
+  priority: 42,
+  atNodeCreation({ ctx, nodeID, value, node, fullName, addNodeHook }) {
+    const type = node.getAttribute("type");
+    let handler;
+    let event = fullName.includes(".lazy") ? "change" : "input";
+    const expr = ctx.formatExpression(value);
+    if (node.tagName === "select") {
+      ctx.addLine(`p${nodeID}.props = {value: ${expr}};`);
+      addNodeHook("create", `n.elm.value=${expr};`);
+      event = "change";
+      handler = `(ev) => {${expr} = ev.target.value}`;
+    } else if (type === "checkbox") {
+      ctx.addLine(`p${nodeID}.props = {checked: ${expr}};`);
+      handler = `(ev) => {${expr} = ev.target.checked}`;
+    } else if (type === "radio") {
+      const nodeValue = node.getAttribute("value")!;
+      ctx.addLine(`p${nodeID}.props = {checked:${expr} === '${nodeValue}'};`);
+      handler = `(ev) => {${expr} = ev.target.value}`;
+      event = "click";
+    } else {
+      ctx.addLine(`p${nodeID}.props = {value: ${expr}};`);
+      const trimCode = fullName.includes(".trim") ? ".trim()" : "";
+      let valueCode = `ev.target.value${trimCode}`;
+      if (fullName.includes(".number")) {
+        ctx.rootContext.shouldDefineUtils = true;
+        valueCode = `utils.toNumber(${valueCode})`;
+      }
+      handler = `(ev) => {${expr} = ${valueCode}}`;
+    }
+    ctx.addLine(
+      `extra.handlers['${event}' + ${nodeID}] = extra.handlers['${event}' + ${nodeID}] || (${handler});`
+    );
+    ctx.addLine(`p${nodeID}.on['${event}'] = extra.handlers['${event}' + ${nodeID}];`);
+  }
+});

src/qweb/index.ts

@@ -0,0 +1,4 @@
+import "./base_directives";
+import "./extensions";
+
+export { CompiledTemplate, QWeb } from "./qweb";

src/qweb/qweb.ts

@@ -1,5 +1,8 @@
-import { VNode, h } from "./vdom";
-import { QWebVar, compileExpr } from "./qweb_expressions";
+import { EventBus } from "../core/event_bus";
+import { h, patch, VNode } from "../vdom/index";
+import { CompilationContext } from "./compilation_context";
+import { shallowEqual } from "../utils";
+import { addNS } from "../vdom/vdom";
 
 /**
  * Owl QWeb Engine
@@ -33,7 +36,7 @@ interface Template {
 interface CompilationInfo {
   node: Element;
   qweb: QWeb;
-  ctx: Context;
+  ctx: CompilationContext;
   fullName: string;
   value: string;
 }
@@ -58,120 +61,161 @@ export interface Directive {
 // Const/global stuff/helpers
 //------------------------------------------------------------------------------
 
-const DISABLED_TAGS = [
-  "input",
-  "textarea",
-  "button",
-  "select",
-  "option",
-  "optgroup"
-];
+const DISABLED_TAGS = ["input", "textarea", "button", "select", "option", "optgroup"];
 
 const lineBreakRE = /[\r\n]/;
 const whitespaceRE = /\s+/g;
 
-const DIRECTIVE_NAMES = {
-  name: 1,
-  att: 1,
-  attf: 1,
-  key: 1
-};
-
-const DIRECTIVES: Directive[] = [];
-
 const NODE_HOOKS_PARAMS = {
   create: "(_, n)",
   insert: "vn",
-  remove: "(vn, rm)"
+  remove: "(vn, rm)",
+  destroy: "()"
 };
 
 interface Utils {
-  h: typeof h;
-  objectToAttrString(obj: Object): string;
+  toObj(expr: any): Object;
   shallowEqual(p1: Object, p2: Object): boolean;
   [key: string]: any;
 }
 
-export const UTILS: Utils = {
-  h: h,
-  objectToAttrString(obj: Object): string {
-    let classes: string[] = [];
-    for (let k in obj) {
-      if (obj[k]) {
-        classes.push(k);
+const UTILS: Utils = {
+  toObj(expr) {
+    if (typeof expr === "string") {
+      expr = expr.trim();
+      if (!expr) {
+        return {};
       }
+      let words = expr.split(/\s+/);
+      let result = {};
+      for (let i = 0; i < words.length; i++) {
+        result[words[i]] = true;
+      }
+      return result;
     }
-    return classes.join(" ");
+    return expr;
   },
-  shallowEqual(p1, p2) {
-    for (let k in p1) {
-      if (p1[k] !== p2[k]) {
-        return false;
-      }
-    }
-    return true;
+  shallowEqual,
+  addNameSpace(vnode) {
+    addNS(vnode.data, vnode.children, vnode.sel);
   }
 };
 
 function parseXML(xml: string): Document {
   const parser = new DOMParser();
+
   const doc = parser.parseFromString(xml, "text/xml");
   if (doc.getElementsByTagName("parsererror").length) {
-    throw new Error("Invalid XML in template");
+    let msg = "Invalid XML in template.";
+    const parsererrorText = doc.getElementsByTagName("parsererror")[0].textContent;
+    if (parsererrorText) {
+      msg += "\nThe parser has produced the following error message:\n" + parsererrorText;
+      const re = /\d+/g;
+      const firstMatch = re.exec(parsererrorText);
+      if (firstMatch) {
+        const lineNumber = Number(firstMatch[0]);
+        const line = xml.split("\n")[lineNumber - 1];
+        const secondMatch = re.exec(parsererrorText);
+        if (line && secondMatch) {
+          const columnIndex = Number(secondMatch[0]) - 1;
+          if (line[columnIndex]) {
+            msg +=
+              `\nThe error might be located at xml line ${lineNumber} column ${columnIndex}\n` +
+              `${line}\n${"-".repeat(columnIndex - 1)}^`;
+          }
+        }
+      }
+    }
+    throw new Error(msg);
   }
   return doc;
 }
 
-let nextID = 1;
-
 //------------------------------------------------------------------------------
 // QWeb rendering engine
 //------------------------------------------------------------------------------
-export class QWeb {
-  templates: { [name: string]: Template } = {};
-  utils = UTILS;
-  static widgets = Object.create(null);
+export class QWeb extends EventBus {
+  templates: { [name: string]: Template };
+  static utils = UTILS;
+  static components = Object.create(null);
 
+  static DIRECTIVE_NAMES: { [key: string]: 1 } = {
+    name: 1,
+    att: 1,
+    attf: 1,
+    key: 1
+  };
+  static DIRECTIVES: Directive[] = [];
+
+  static TEMPLATES: { [name: string]: Template } = {};
+
+  static nextId: number = 1;
+
+  h = h;
   // dev mode enables better error messages or more costly validations
   static dev: boolean = false;
 
-  // the id field is useful to be able to hash qweb instances.  The current
-  // use case is that component's templates are qweb dependant, and need to be
-  // able to map a qweb instance to a template name.
-  id = nextID++;
-
-  // slots contains sub templates defined with t-set inside t-widget nodes, and
+  // slots contains sub templates defined with t-set inside t-component nodes, and
   // are meant to be used by the t-slot directive.
-  slots = {};
-  nextSlotId = 1;
+  static slots = {};
+  static nextSlotId = 1;
+
+  // recursiveTemplates contains sub templates called with t-call, but which
+  // ends up in recursive situations.  This is very similar to the slot situation,
+  // as in we need to propagate the scope.
+  recursiveFns = {};
+
+  isUpdating: boolean = false;
 
   constructor(data?: string) {
+    super();
+    this.templates = Object.create(QWeb.TEMPLATES);
     if (data) {
       this.addTemplates(data);
     }
   }
 
   static addDirective(directive: Directive) {
-    DIRECTIVES.push(directive);
-    DIRECTIVE_NAMES[directive.name] = 1;
-    DIRECTIVES.sort((d1, d2) => d1.priority - d2.priority);
+    if (directive.name in QWeb.DIRECTIVE_NAMES) {
+      throw new Error(`Directive "${directive.name} already registered`);
+    }
+    QWeb.DIRECTIVES.push(directive);
+    QWeb.DIRECTIVE_NAMES[directive.name] = 1;
+    QWeb.DIRECTIVES.sort((d1, d2) => d1.priority - d2.priority);
     if (directive.extraNames) {
-      directive.extraNames.forEach(n => (DIRECTIVE_NAMES[n] = 1));
+      directive.extraNames.forEach(n => (QWeb.DIRECTIVE_NAMES[n] = 1));
     }
   }
 
-  static register(name: string, Component: any) {
-    if (QWeb.widgets[name]) {
+  static registerComponent(name: string, Component: any) {
+    if (QWeb.components[name]) {
       throw new Error(`Component '${name}' has already been registered`);
     }
-    QWeb.widgets[name] = Component;
+    QWeb.components[name] = Component;
+  }
+
+  /**
+   * Register globally a template.  All QWeb instances will obtain their
+   * templates from their own template map, and then, from the global static
+   * TEMPLATES property.
+   */
+  static registerTemplate(name: string, template: string) {
+    if (QWeb.TEMPLATES[name]) {
+      throw new Error(`Template '${name}' has already been registered`);
+    }
+    const qweb = new QWeb();
+    qweb.addTemplate(name, template);
+    QWeb.TEMPLATES[name] = qweb.templates[name];
   }
 
   /**
    * Add a template to the internal template map.  Note that it is not
    * immediately compiled.
    */
-  addTemplate(name: string, xmlString: string) {
+  addTemplate(name: string, xmlString: string, allowDuplicate?: boolean) {
+    if (allowDuplicate && name in this.templates) {
+      return;
+    }
     const doc = parseXML(xmlString);
     if (!doc.firstChild) {
       throw new Error("Invalid template (should not be empty)");
@@ -180,12 +224,12 @@ export class QWeb {
   }
 
   /**
-   * Load templates from a xml (as a string).  This will look up for the first
-   * <templates> tag, and will consider each child of this as a template, with
-   * the name given by the t-name attribute.
+   * Load templates from a xml (as a string or xml document).  This will look up
+   * for the first <templates> tag, and will consider each child of this as a
+   * template, with the name given by the t-name attribute.
    */
-  addTemplates(xmlstr: string) {
-    const doc = parseXML(xmlstr);
+  addTemplates(xmlstr: string | Document) {
+    const doc = typeof xmlstr === "string" ? parseXML(xmlstr) : xmlstr;
     const templates = doc.getElementsByTagName("templates")[0];
     if (!templates) {
       return;
@@ -203,7 +247,7 @@ export class QWeb {
     this._processTemplate(elem);
     const template = {
       elem,
-      fn: (context, extra) => {
+      fn: function(this: QWeb, context, extra) {
         const compiledFunction = this._compile(name, elem);
         template.fn = compiledFunction;
         return compiledFunction.call(this, context, extra);
@@ -234,9 +278,7 @@ export class QWeb {
             return a + b;
           }) > 1
         ) {
-          throw new Error(
-            "Only one conditional branching directive is allowed per node"
-          );
+          throw new Error("Only one conditional branching directive is allowed per node");
         }
         // All text nodes between branch nodes are removed
         let textNode;
@@ -266,53 +308,98 @@ export class QWeb {
     return template.fn.call(this, context, extra);
   }
 
-  _compile(name: string, elem: Element): CompiledTemplate {
+  /**
+   * Render a template to a html string.
+   *
+   * Note that this is more limited than the `render` method: it is not suitable
+   * to render a full component tree, since this is an asynchronous operation.
+   * This method can only render templates without components.
+   */
+  renderToString(name: string, context: EvalContext = {}, extra?: any): string {
+    const vnode = this.render(name, context, extra);
+    if (vnode.sel === undefined) {
+      return vnode.text!;
+    }
+    const node = document.createElement(vnode.sel);
+    const result = patch(node, vnode);
+    return (<HTMLElement>result.elm).outerHTML;
+  }
+
+  /**
+   * Force all widgets connected to this QWeb instance to rerender themselves.
+   *
+   * This method is mostly useful for external code that want to modify the
+   * application in some cases.  For example, a router plugin.
+   */
+  forceUpdate() {
+    this.isUpdating = true;
+    Promise.resolve().then(() => {
+      if (this.isUpdating) {
+        this.isUpdating = false;
+        this.trigger("update");
+      }
+    });
+  }
+
+  _compile(name: string, elem: Element, parentContext?: CompilationContext): CompiledTemplate {
     const isDebug = elem.attributes.hasOwnProperty("t-debug");
-    const ctx = new Context(name);
+    const ctx = new CompilationContext(name);
+    if (elem.tagName !== "t") {
+      ctx.shouldDefineResult = false;
+    }
+    if (parentContext) {
+      ctx.templates = Object.create(parentContext.templates);
+      ctx.variables = Object.create(parentContext.variables);
+      ctx.nextID = parentContext.nextID + 1;
+      ctx.parentNode = parentContext.parentNode || ctx.nextID++;
+      ctx.allowMultipleRoots = true;
+      ctx.hasParentWidget = true;
+      ctx.shouldDefineResult = false;
+      ctx.addLine(`let c${ctx.parentNode} = extra.parentNode;`);
+
+      for (let v in parentContext.variables) {
+        let variable = <any>parentContext.variables[v];
+        if (variable.id) {
+          ctx.addLine(`let ${variable.id} = extra.fiber.vars.${variable.id}`);
+        }
+      }
+    }
+    if (parentContext) {
+      ctx.addLine("    Object.assign(context, extra.fiber.scope);");
+    }
     this._compileNode(elem, ctx);
 
-    if (ctx.shouldProtectContext) {
-      ctx.code.unshift("    context = Object.create(context);");
-    }
-    if (ctx.shouldDefineOwner) {
-      // this is necessary to prevent some directives (t-forach for ex) to
-      // pollute the rendering context by adding some keys in it.
-      ctx.code.unshift("    let owner = context;");
-    }
-    if (ctx.shouldDefineQWeb) {
-      ctx.code.unshift("    let QWeb = this.constructor;");
-    }
-    if (ctx.shouldDefineUtils) {
-      ctx.code.unshift("    let utils = this.utils;");
+    if (!parentContext) {
+      if (ctx.shouldDefineResult) {
+        ctx.addLine(`return result;`);
+      } else {
+        if (!ctx.rootNode) {
+          throw new Error(`A template should have one root node (${ctx.templateName})`);
+        }
+        ctx.addLine(`return vn${ctx.rootNode};`);
+      }
     }
 
-    if (!ctx.rootNode) {
-      throw new Error("A template should have one root node");
-    }
-    ctx.addLine(`return vn${ctx.rootNode};`);
+    let code = ctx.generateCode();
+
     let template;
     try {
-      template = new Function(
-        "context",
-        "extra",
-        ctx.code.join("\n")
-      ) as CompiledTemplate;
+      template = new Function("context", "extra", code.join("\n")) as CompiledTemplate;
     } catch (e) {
       const templateName = ctx.templateName.replace(/`/g, "'");
       console.groupCollapsed(`Invalid Code generated by ${templateName}`);
-      console.warn(ctx.code.join("\n"));
+      console.warn(code.join("\n"));
       console.groupEnd();
       throw new Error(
-        `Invalid generated code while compiling template '${templateName}': ${
-          e.message
-        }`
+        `Invalid generated code while compiling template '${templateName}': ${e.message}`
       );
     }
     if (isDebug) {
-      console.log(
-        `Template: ${this.templates[name].elem.outerHTML}\nCompiled code:\n` +
-          template.toString()
-      );
+      const tpl = this.templates[name];
+      if (tpl) {
+        const msg = `Template: ${tpl.elem.outerHTML}\nCompiled code:\n${template.toString()}`;
+        console.log(msg);
+      }
     }
     return template;
   }
@@ -321,7 +408,7 @@ export class QWeb {
    * Generate code from an xml node
    *
    */
-  _compileNode(node: ChildNode, ctx: Context) {
+  _compileNode(node: ChildNode, ctx: CompilationContext) {
     if (!(node instanceof Element)) {
       // this is a text node, there are no directive to apply
       let text = node.textContent!;
@@ -332,7 +419,11 @@ export class QWeb {
         text = text.replace(whitespaceRE, " ");
       }
       if (ctx.parentNode) {
-        ctx.addLine(`c${ctx.parentNode}.push({text: \`${text}\`});`);
+        if (node.nodeType === 3) {
+          ctx.addLine(`c${ctx.parentNode}.push({text: \`${text}\`});`);
+        } else if (node.nodeType === 8) {
+          ctx.addLine(`c${ctx.parentNode}.push(h('!', \`${text}\`));`);
+        }
       } else if (ctx.parentTextNode) {
         ctx.addLine(`vn${ctx.parentTextNode}.text += \`${text}\`;`);
       } else {
@@ -340,12 +431,19 @@ export class QWeb {
         // template rendering.
         let nodeID = ctx.generateID();
         ctx.addLine(`var vn${nodeID} = {text: \`${text}\`};`);
+        ctx.addLine(`result = vn${nodeID};`);
         ctx.rootContext.rootNode = nodeID;
         ctx.rootContext.parentTextNode = nodeID;
       }
       return;
     }
 
+    const firstLetter = node.tagName[0];
+    if (firstLetter === firstLetter.toUpperCase()) {
+      // this is a component, we modify in place the xml document to change
+      // <SomeComponent ... /> to <t t-component="SomeComponent" ... />
+      node.setAttribute("t-component", node.tagName);
+    }
     const attributes = (<Element>node).attributes;
 
     const validDirectives: {
@@ -354,7 +452,7 @@ export class QWeb {
       fullName: string;
     }[] = [];
 
-    let withHandlers = false;
+    const finalizers: typeof validDirectives = [];
 
     // maybe this is not optimal: we iterate on all attributes here, and again
     // just after for each directive.
@@ -362,16 +460,26 @@ export class QWeb {
       let attrName = attributes[i].name;
       if (attrName.startsWith("t-")) {
         let dName = attrName.slice(2).split(/-|\./)[0];
-        if (!(dName in DIRECTIVE_NAMES)) {
+        if (!(dName in QWeb.DIRECTIVE_NAMES)) {
           throw new Error(`Unknown QWeb directive: '${attrName}'`);
         }
+        if (node.tagName !== "t" && (attrName === "t-esc" || attrName === "t-raw")) {
+          const tNode = document.createElement("t");
+          tNode.setAttribute(attrName, node.getAttribute(attrName)!);
+          for (let child of Array.from(node.childNodes)) {
+            tNode.appendChild(child);
+          }
+          node.appendChild(tNode);
+          node.removeAttribute(attrName);
+        }
       }
     }
 
-    const DIR_N = DIRECTIVES.length;
+    const DIR_N = QWeb.DIRECTIVES.length;
     const ATTR_N = attributes.length;
+    let withHandlers = false;
     for (let i = 0; i < DIR_N; i++) {
-      let directive = DIRECTIVES[i];
+      let directive = QWeb.DIRECTIVES[i];
       let fullName;
       let value;
       for (let j = 0; j < ATTR_N; j++) {
@@ -384,13 +492,17 @@ export class QWeb {
           fullName = name;
           value = attributes[j].textContent;
           validDirectives.push({ directive, value, fullName });
-          if (directive.name === "on" || directive.name === 'model') {
+          if (directive.name === "on" || directive.name === "model") {
             withHandlers = true;
           }
         }
       }
     }
+
     for (let { directive, value, fullName } of validDirectives) {
+      if (directive.finalize) {
+        finalizers.push({ directive, value, fullName });
+      }
       if (directive.atNodeEncounter) {
         const isDone = directive.atNodeEncounter({
           node,
@@ -400,6 +512,9 @@ export class QWeb {
           value
         });
         if (isDone) {
+          for (let { directive, value, fullName } of finalizers) {
+            directive.finalize!({ node, qweb: this, ctx, fullName, value });
+          }
           return;
         }
       }
@@ -408,6 +523,7 @@ export class QWeb {
     if (node.nodeName !== "t") {
       let nodeID = this._compileGenericNode(node, ctx, withHandlers);
       ctx = ctx.withParent(nodeID);
+      ctx = ctx.subContext("currentKey", ctx.lastNodeKey);
       let nodeHooks = {};
       let addNodeHook = function(hook, handler) {
         nodeHooks[hook] = nodeHooks[hook] || [];
@@ -445,17 +561,26 @@ export class QWeb {
     }
 
     this._compileChildren(node, ctx);
+    // svg support
+    // we hadd svg namespace if it is a svg or if it is a g, but only if it is
+    // the root node.  This is the easiest way to support svg sub components:
+    // they need to have a g tag as root. Otherwise, we would need a complete
+    // list of allowed svg tags.
+    const shouldAddNS =
+      node.nodeName === "svg" || (node.nodeName === "g" && ctx.rootNode === ctx.parentNode);
+    if (shouldAddNS) {
+      ctx.rootContext.shouldDefineUtils = true;
+      ctx.addLine(`utils.addNameSpace(vn${ctx.parentNode});`);
+    }
 
-    for (let { directive, value, fullName } of validDirectives) {
-      if (directive.finalize) {
-        directive.finalize({ node, qweb: this, ctx, fullName, value });
-      }
+    for (let { directive, value, fullName } of finalizers) {
+      directive.finalize!({ node, qweb: this, ctx, fullName, value });
     }
   }
 
   _compileGenericNode(
     node: ChildNode,
-    ctx: Context,
+    ctx: CompilationContext,
     withHandlers: boolean = true
   ): number {
     // nodeType 1 is generic tag
@@ -481,67 +606,76 @@ export class QWeb {
       if (key === "disabled" && DISABLED_TAGS.indexOf(node.nodeName) > -1) {
         isProp = true;
       }
-      if (
-        (key === "readonly" && node.nodeName === "input") ||
-        node.nodeName === "textarea"
-      ) {
+      if ((key === "readonly" && node.nodeName === "input") || node.nodeName === "textarea") {
         isProp = true;
       }
       if (isProp) {
         props.push(`${key}: _${val}`);
       }
     }
+    let classObj = "";
 
     for (let i = 0; i < attributes.length; i++) {
       let name = attributes[i].name;
       const value = attributes[i].textContent!;
 
       // regular attributes
-      if (
-        !name.startsWith("t-") &&
-        !(<Element>node).getAttribute("t-attf-" + name)
-      ) {
+      if (!name.startsWith("t-") && !(<Element>node).getAttribute("t-attf-" + name)) {
         const attID = ctx.generateID();
-        ctx.addLine(`var _${attID} = '${value}';`);
-        if (!name.match(/^[a-zA-Z]+$/)) {
-          // attribute contains 'non letters' => we want to quote it
-          name = '"' + name + '"';
+        if (name === "class") {
+          let classDef = value
+            .trim()
+            .split(/\s+/)
+            .map(a => `'${a}':true`)
+            .join(",");
+          classObj = `_${ctx.generateID()}`;
+          ctx.addLine(`let ${classObj} = {${classDef}};`);
+        } else {
+          ctx.addLine(`var _${attID} = '${value}';`);
+          if (!name.match(/^[a-zA-Z]+$/)) {
+            // attribute contains 'non letters' => we want to quote it
+            name = '"' + name + '"';
+          }
+          attrs.push(`${name}: _${attID}`);
+          handleBooleanProps(name, attID);
         }
-        attrs.push(`${name}: _${attID}`);
-        handleBooleanProps(name, attID);
       }
 
       // dynamic attributes
       if (name.startsWith("t-att-")) {
         let attName = name.slice(6);
         const v = ctx.getValue(value);
-        let formattedValue = v.id || ctx.formatExpression(v);
-        if (
-          formattedValue[0] === "{" &&
-          formattedValue[formattedValue.length - 1] === "}"
-        ) {
-          formattedValue = `this.utils.objectToAttrString(${formattedValue})`;
+        let formattedValue = typeof v === "string" ? ctx.formatExpression(v) : v.id;
+
+        if (attName === "class") {
+          ctx.rootContext.shouldDefineUtils = true;
+          formattedValue = `utils.toObj(${formattedValue})`;
+          if (classObj) {
+            ctx.addLine(`Object.assign(${classObj}, ${formattedValue})`);
+          } else {
+            classObj = `_${ctx.generateID()}`;
+            ctx.addLine(`let ${classObj} = ${formattedValue};`);
+          }
+        } else {
+          const attID = ctx.generateID();
+          if (!attName.match(/^[a-zA-Z]+$/)) {
+            // attribute contains 'non letters' => we want to quote it
+            attName = '"' + attName + '"';
+          }
+          // we need to combine dynamic with non dynamic attributes:
+          // class="a" t-att-class="'yop'" should be rendered as class="a yop"
+          const attValue = (<Element>node).getAttribute(attName);
+          if (attValue) {
+            const attValueID = ctx.generateID();
+            ctx.addLine(`var _${attValueID} = ${formattedValue};`);
+            formattedValue = `'${attValue}' + (_${attValueID} ? ' ' + _${attValueID} : '')`;
+            const attrIndex = attrs.findIndex(att => att.startsWith(attName + ":"));
+            attrs.splice(attrIndex, 1);
+          }
+          ctx.addLine(`var _${attID} = ${formattedValue};`);
+          attrs.push(`${attName}: _${attID}`);
+          handleBooleanProps(attName, attID);
         }
-        const attID = ctx.generateID();
-        if (!attName.match(/^[a-zA-Z]+$/)) {
-          // attribute contains 'non letters' => we want to quote it
-          attName = '"' + attName + '"';
-        }
-        // we need to combine dynamic with non dynamic attributes:
-        // class="a" t-att-class="'yop'" should be rendered as class="a yop"
-        const attValue = (<Element>node).getAttribute(attName);
-        if (attValue) {
-          const attValueID = ctx.generateID();
-          ctx.addLine(`var _${attValueID} = ${formattedValue};`);
-          formattedValue = `'${attValue}' + (_${attValueID} ? ' ' + _${attValueID} : '')`;
-          const attrIndex = attrs.findIndex(att =>
-            att.startsWith(attName + ":")
-          );
-          attrs.splice(attrIndex, 1);
-        }
-        ctx.addLine(`var _${attID} = ${formattedValue};`);
-        attrs.push(`${attName}: _${attID}`);
-        handleBooleanProps(attName, attID);
       }
 
       if (name.startsWith("t-attf-")) {
@@ -571,7 +705,9 @@ export class QWeb {
     let nodeID = ctx.generateID();
     let nodeKey: any = (<Element>node).getAttribute("t-key");
     if (nodeKey) {
-      nodeKey = ctx.formatExpression(nodeKey);
+      ctx.addLine(`const nodeKey${nodeID} = ${ctx.formatExpression(nodeKey)}`);
+      nodeKey = `nodeKey${nodeID}`;
+      ctx.lastNodeKey = nodeKey;
     } else {
       nodeKey = nodeID;
     }
@@ -582,6 +718,9 @@ export class QWeb {
     if (props.length > 0) {
       parts.push(`props:{${props.join(",")}}`);
     }
+    if (classObj) {
+      parts.push(`class:${classObj}`);
+    }
     if (withHandlers) {
       parts.push(`on:{}`);
     }
@@ -598,9 +737,7 @@ export class QWeb {
       ctx.addLine(`}`);
       ctx.closeIf();
     }
-    ctx.addLine(
-      `var vn${nodeID} = h('${node.nodeName}', p${nodeID}, c${nodeID});`
-    );
+    ctx.addLine(`var vn${nodeID} = h('${node.nodeName}', p${nodeID}, c${nodeID});`);
     if (ctx.parentNode) {
       ctx.addLine(`c${ctx.parentNode}.push(vn${nodeID});`);
     }
@@ -608,7 +745,7 @@ export class QWeb {
     return nodeID;
   }
 
-  _compileChildren(node: ChildNode, ctx: Context) {
+  _compileChildren(node: ChildNode, ctx: CompilationContext) {
     if (node.childNodes.length > 0) {
       for (let child of Array.from(node.childNodes)) {
         this._compileNode(child, ctx);
@@ -616,118 +753,3 @@ export class QWeb {
     }
   }
 }
-
-//------------------------------------------------------------------------------
-// Compilation Context
-//------------------------------------------------------------------------------
-
-export class Context {
-  nextID: number = 1;
-  code: string[] = [];
-  variables: { [key: string]: QWebVar } = {};
-  escaping: boolean = false;
-  parentNode: number | null = null;
-  parentTextNode: number | null = null;
-  rootNode: number | null = null;
-  indentLevel: number = 0;
-  rootContext: Context;
-  caller: Element | undefined;
-  shouldDefineOwner: boolean = false;
-  shouldDefineQWeb: boolean = false;
-  shouldDefineUtils: boolean = false;
-  shouldProtectContext: boolean = false;
-  inLoop: boolean = false;
-  inPreTag: boolean = false;
-  templateName: string;
-
-  constructor(name?: string) {
-    this.rootContext = this;
-    this.templateName = name || "noname";
-    this.addLine("var h = this.utils.h;");
-  }
-
-  generateID(): number {
-    const id = this.rootContext.nextID++;
-    return id;
-  }
-
-  withParent(node: number): Context {
-    if (this === this.rootContext && (this.parentNode || this.parentTextNode)) {
-      throw new Error("A template should not have more than one root node");
-    }
-    if (!this.rootContext.rootNode) {
-      this.rootContext.rootNode = node;
-    }
-    return this.subContext("parentNode", node);
-  }
-
-  subContext(key: keyof Context, value: any): Context {
-    const newContext = Object.create(this);
-    newContext[key] = value;
-    return newContext;
-  }
-
-  indent() {
-    this.indentLevel++;
-  }
-
-  dedent() {
-    this.indentLevel--;
-  }
-
-  addLine(line: string) {
-    const prefix = new Array(this.indentLevel + 2).join("    ");
-    this.code.push(prefix + line);
-  }
-
-  addIf(condition: string) {
-    this.addLine(`if (${condition}) {`);
-    this.indent();
-  }
-
-  addElse() {
-    this.dedent();
-    this.addLine("} else {");
-    this.indent();
-  }
-
-  closeIf() {
-    this.dedent();
-    this.addLine("}");
-  }
-
-  getValue(val: any): any {
-    return val in this.variables ? this.getValue(this.variables[val]) : val;
-  }
-
-  /**
-   * Prepare an expression for being consumed at render time.  Its main job
-   * is to
-   * - replace unknown variables by a lookup in the context
-   * - replace already defined variables by their internal name
-   */
-  formatExpression(expr: string): string {
-    return compileExpr(expr, this.variables);
-  }
-
-  /**
-   * Perform string interpolation on the given string. Note that if the whole
-   * string is an expression, it simply returns it (formatted and enclosed in
-   * parentheses).
-   * For instance:
-   *   'Hello {{x}}!' -> `Hello ${x}`
-   *   '{{x ? 'a': 'b'}}' -> (x ? 'a' : 'b')
-   */
-  interpolate(s: string): string {
-    let matches = s.match(/\{\{.*?\}\}/g);
-    if (matches && matches[0].length === s.length) {
-      return `(${this.formatExpression(s.slice(2, -2))})`;
-    }
-
-    let r = s.replace(
-      /\{\{.*?\}\}/g,
-      s => "${" + this.formatExpression(s.slice(2, -2)) + "}"
-    );
-    return "`" + r + "`";
-  }
-}

src/qweb_extensions.ts

@@ -1,722 +0,0 @@
-import { QWeb, UTILS } from "./qweb_core";
-import { VNode } from "./vdom";
-
-/**
- * Owl QWeb Extensions
- *
- * This file contains the implementation of non standard QWeb directives, added
- * by Owl and that will only work on Owl projects:
- *
- * - t-on
- * - t-ref
- * - t-transition
- * - t-widget/t-keepalive
- * - t-mounted
- * - t-slot
- * - t-model
- */
-
-//------------------------------------------------------------------------------
-// t-on
-//------------------------------------------------------------------------------
-// these are pieces of code that will be injected into the event handler if
-// modifiers are specified
-const MODS_CODE = {
-  prevent: "e.preventDefault();",
-  self: "if (e.target !== this.elm) {return}",
-  stop: "e.stopPropagation();"
-};
-
-QWeb.addDirective({
-  name: "on",
-  priority: 90,
-  atNodeCreation({ ctx, fullName, value, nodeID }) {
-    ctx.rootContext.shouldDefineOwner = true;
-    const [eventName, ...mods] = fullName.slice(5).split(".");
-    if (!eventName) {
-      throw new Error("Missing event name with t-on directive");
-    }
-    let extraArgs;
-    let handlerName = value.replace(/\(.*\)/, function(args) {
-      extraArgs = args.slice(1, -1);
-      return "";
-    });
-    ctx.addIf(`!context['${handlerName}']`);
-    ctx.addLine(
-      `throw new Error('Missing handler \\'' + '${handlerName}' + \`\\' when evaluating template '${ctx.templateName.replace(
-        /`/g,
-        "'"
-      )}'\`)`
-    );
-    ctx.closeIf();
-    let params = extraArgs
-      ? `owner, ${ctx.formatExpression(extraArgs)}`
-      : "owner";
-    let handler;
-    if (mods.length > 0) {
-      handler = `function (e) {`;
-      handler += mods
-        .map(function(mod) {
-          return MODS_CODE[mod];
-        })
-        .join("");
-      handler += `context['${handlerName}'].call(${params}, e);}`;
-    } else {
-      handler = `context['${handlerName}'].bind(${params})`;
-    }
-    if (extraArgs) {
-      ctx.addLine(`p${nodeID}.on['${eventName}'] = ${handler};`);
-    } else {
-      ctx.addLine(
-        `extra.handlers['${eventName}' + ${nodeID}] = extra.handlers['${eventName}' + ${nodeID}] || ${handler};`
-      );
-      ctx.addLine(
-        `p${nodeID}.on['${eventName}'] = extra.handlers['${eventName}' + ${nodeID}];`
-      );
-    }
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-ref
-//------------------------------------------------------------------------------
-QWeb.addDirective({
-  name: "ref",
-  priority: 95,
-  atNodeCreation({ ctx, value, addNodeHook }) {
-    const refKey = `ref${ctx.generateID()}`;
-    ctx.addLine(`const ${refKey} = ${ctx.interpolate(value)};`);
-    addNodeHook("create", `context.refs[${refKey}] = n.elm;`);
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-transition
-//------------------------------------------------------------------------------
-UTILS.nextFrame = function(cb: () => void) {
-  requestAnimationFrame(() => requestAnimationFrame(cb));
-};
-
-UTILS.transitionInsert = function(vn: VNode, name: string) {
-  const elm = <HTMLElement>vn.elm;
-  // remove potential duplicated vnode that is currently being removed, to
-  // prevent from having twice the same node in the DOM during an animation
-  const dup =
-    elm.parentElement &&
-    elm.parentElement!.querySelector(`*[data-owl-key='${vn.key}']`);
-  if (dup) {
-    dup.remove();
-  }
-
-  elm.classList.add(name + "-enter");
-  elm.classList.add(name + "-enter-active");
-  const finalize = () => {
-    elm.classList.remove(name + "-enter-active");
-    elm.classList.remove(name + "-enter-to");
-  };
-  this.nextFrame(() => {
-    elm.classList.remove(name + "-enter");
-    elm.classList.add(name + "-enter-to");
-    whenTransitionEnd(elm, finalize);
-  });
-};
-
-UTILS.transitionRemove = function(vn: VNode, name: string, rm: () => void) {
-  const elm = <HTMLElement>vn.elm;
-  elm.setAttribute("data-owl-key", vn.key!);
-
-  elm.classList.add(name + "-leave");
-  elm.classList.add(name + "-leave-active");
-  const finalize = () => {
-    elm.classList.remove(name + "-leave-active");
-    elm.classList.remove(name + "-leave-to");
-    rm();
-  };
-  this.nextFrame(() => {
-    elm.classList.remove(name + "-leave");
-    elm.classList.add(name + "-leave-to");
-    whenTransitionEnd(elm, finalize);
-  });
-};
-
-function getTimeout(delays: Array<string>, durations: Array<string>): number {
-  /* istanbul ignore next */
-  while (delays.length < durations.length) {
-    delays = delays.concat(delays);
-  }
-
-  return Math.max.apply(
-    null,
-    durations.map((d, i) => {
-      return toMs(d) + toMs(delays[i]);
-    })
-  );
-}
-
-// Old versions of Chromium (below 61.0.3163.100) formats floating pointer numbers
-// in a locale-dependent way, using a comma instead of a dot.
-// If comma is not replaced with a dot, the input will be rounded down (i.e. acting
-// as a floor function) causing unexpected behaviors
-function toMs(s: string): number {
-  return Number(s.slice(0, -1).replace(",", ".")) * 1000;
-}
-
-function whenTransitionEnd(elm: HTMLElement, cb) {
-  const styles = window.getComputedStyle(elm);
-  const delays: Array<string> = (styles.transitionDelay || "").split(", ");
-  const durations: Array<string> = (styles.transitionDuration || "").split(
-    ", "
-  );
-  const timeout: number = getTimeout(delays, durations);
-  if (timeout > 0) {
-    elm.addEventListener("transitionend", cb, { once: true });
-  } else {
-    cb();
-  }
-}
-
-QWeb.addDirective({
-  name: "transition",
-  priority: 96,
-  atNodeCreation({ value, addNodeHook }) {
-    let name = value;
-    const hooks = {
-      insert: `this.utils.transitionInsert(vn, '${name}');`,
-      remove: `this.utils.transitionRemove(vn, '${name}', rm);`
-    };
-    for (let hookName in hooks) {
-      addNodeHook(hookName, hooks[hookName]);
-    }
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-widget
-//------------------------------------------------------------------------------
-
-const T_WIDGET_MODS_CODE = Object.assign({}, MODS_CODE, {
-  self: "if (e.target !== vn.elm) {return}"
-});
-
-/**
- * The t-widget directive is certainly a complicated and hard to maintain piece
- * of code.  To help you, fellow developer, if you have to maintain it, I offer
- * you this advice: Good luck...
- *
- * Since it is not 'direct' code, but rather code that generates other code, it
- * is not easy to understand.  To help you, here  is a detailed and commented
- * explanation of the code generated by the t-widget directive for the following
- * situation:
- * ```xml
- *   <t t-widget="child"
- *      t-key="'somestring'"
- *      flag="state.flag"
- *      t-transition="fade"/>
- * ```
- *
- * ```js
- * // we assign utils on top of the function because it will be useful for
- * // each widgets
- * let utils = this.utils;
- *
- * // this is the virtual node representing the parent div
- * let c1 = [], p1 = { key: 1 };
- * var vn1 = h("div", p1, c1);
- *
- * // t-widget directive: we start by evaluating the expression given by t-key:
- * let key5 = "somestring";
- *
- * // def3 is the promise that will contain later either the new widget
- * // creation, or the props update...
- * let def3;
- *
- * // this is kind of tricky: we need here to find if the widget was already
- * // created by a previous rendering.  This is done by checking the internal
- * // `cmap` (children map) of the parent widget: it maps keys to widget ids,
- * // and, then, if there is an id, we look into the children list to get the
- * // instance
- * let w4 =
- *   key5 in context.__owl__.cmap
- *   ? context.__owl__.children[context.__owl__.cmap[key5]]
- *   : false;
- *
- * // We keep the index of the position of the widget in the closure.  We push
- * // null to reserve the slot, and will replace it later by the widget vnode,
- * // when it will be ready (do not forget that preparing/rendering a widget is
- * // asynchronous)
- * let _2_index = c1.length;
- * c1.push(null);
- *
- * // we evaluate here the props given to the component. It is done here to be
- * // able to easily reference it later, and also, it might be an expensive
- * // computation, so it is certainly better to do it only once
- * let props4 = { flag: context["state"].flag };
- *
- * // If we have a widget, currently rendering, but not ready yet, we do not want
- * // to wait for it to be ready if we can avoid it
- * if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
- *   // we check if the props are the same.  In that case, we can simply reuse
- *   // the previous rendering and skip all useless work
- *   if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
- *     def3 = w4.__owl__.renderPromise;
- *   } else {
- *     // if the props are not the same, we destroy the widget and starts anew.
- *     // this will be faster than waiting for its rendering, then updating it
- *     w4.destroy();
- *     w4 = false;
- *   }
- * }
- *
- * if (!w4) {
- *   // in this situation, we need to create a new widget.  First step is
- *   // to get a reference to the class, then create an instance with
- *   // current context as parent, and the props.
- *   let W4 = context.widgets && context.widgets[widgetKey4] || QWeb.widgets[widgetKey4];
-
- *   if (!W4) {
- *     throw new Error("Cannot find the definition of widget 'child'");
- *   }
- *   w4 = new W4(owner, props4);
- *
- *   // Whenever we rerender the parent widget, we need to be sure that we
- *   // are able to find the widget instance. To do that, we register it to
- *   // the parent cmap (children map).  Note that the 'template' key is
- *   // used here, since this is what identify the widget from the template
- *   // perspective.
- *   context.__owl__.cmap[key5] = w4.__owl__.id;
- *
- *   // _prepare is called, to basically call willStart, then render the
- *   // widget
- *   def3 = w4._prepare();
- *
- *   def3 = def3.then(vnode => {
- *     // we create here a virtual node for the parent (NOT the widget). This
- *     // means that the vdom of the parent will be stopped here, and from
- *     // the parent's perspective, it simply is a vnode with no children.
- *     // However, it shares the same dom element with the component root
- *     // vnode.
- *     let pvnode = h(vnode.sel, { key: key5 });
- *
- *     // we add hooks to the parent vnode so we can interact with the new
- *     // widget at the proper time
- *     pvnode.data.hook = {
- *       insert(vn) {
- *         // the _mount method will patch the widget vdom into the elm vn.elm,
- *         // then call the mounted hooks. However, suprisingly, the snabbdom
- *         // patch method actually replace the elm by a new elm, so we need
- *         // to synchronise the pvnode elm with the resulting elm
- *         let nvn = w4._mount(vnode, vn.elm);
- *         pvnode.elm = nvn.elm;
- *         // what follows is only present if there are animations on the widget
- *         utils.transitionInsert(vn, "fade");
- *       },
- *       remove() {
- *         // override with empty function to prevent from removing the node
- *         // directly. It will be removed when destroy is called anyway, which
- *         // delays the removal if there are animations.
- *       },
- *       destroy() {
- *         // if there are animations, we delay the call to destroy on the
- *         // widget, if not, we call it directly.
- *         let finalize = () => {
- *           w4.destroy();
- *         };
- *         utils.transitionRemove(vn, "fade", finalize);
- *       }
- *     };
- *     // the pvnode is inserted at the correct position in the div's children
- *     c1[_2_index] = pvnode;
- *
- *     // we keep here a reference to the parent vnode (representing the
- *     // widget, so we can reuse it later whenever we update the widget
- *     w4.__owl__.pvnode = pvnode;
- *   });
- * } else {
- *   // this is the 'update' path of the directive.
- *   // the call to _updateProps is the actual widget update
- *   // Note that we only update the props if we cannot reuse the previous
- *   // rendering work (in the case it was rendered with the same props)
- *   def3 = def3 || w4._updateProps(props4, extra.forceUpdate, extra.patchQueue);
- *   def3 = def3.then(() => {
- *     // if widget was destroyed in the meantime, we do nothing (so, this
- *     // means that the parent's element children list will have a null in
- *     // the widget's position, which will cause the pvnode to be removed
- *     // when it is patched.
- *     if (w4.__owl__.isDestroyed) {
- *       return;
- *     }
- *     // like above, we register the pvnode to the children list, so it
- *     // will not be patched out of the dom.
- *     let pvnode = w4.__owl__.pvnode;
- *     c1[_2_index] = pvnode;
- *   });
- * }
- *
- * // we register the deferred here so the parent can coordinate its patch operation
- * // with all the children.
- * extra.promises.push(def3);
- * return vn1;
- * ```
- */
-
-QWeb.addDirective({
-  name: "widget",
-  extraNames: ["props", "keepalive", "asyncroot"],
-  priority: 100,
-  atNodeEncounter({ ctx, value, node, qweb }): boolean {
-    ctx.addLine("//WIDGET");
-    ctx.rootContext.shouldDefineOwner = true;
-    ctx.rootContext.shouldDefineQWeb = true;
-    ctx.rootContext.shouldDefineUtils = true;
-    let keepAlive = node.getAttribute("t-keepalive") ? true : false;
-    let async = node.getAttribute("t-asyncroot") ? true : false;
-
-    // t-on- events and t-transition
-    const events: [string, string[], string, string][] = [];
-    let transition: string = "";
-    const attributes = (<Element>node).attributes;
-    const props: { [key: string]: string } = {};
-    for (let i = 0; i < attributes.length; i++) {
-      const name = attributes[i].name;
-      const value = attributes[i].textContent!;
-      if (name.startsWith("t-on-")) {
-        const [eventName, ...mods] = name.slice(5).split(".");
-        let extraArgs;
-        let handlerName = value.replace(/\(.*\)/, function(args) {
-          extraArgs = args.slice(1, -1);
-          return "";
-        });
-        events.push([eventName, mods, handlerName, extraArgs]);
-      } else if (name === "t-transition") {
-        transition = value;
-      } else if (!name.startsWith("t-")) {
-        if (name !== "class" && name !== "style") {
-          // this is a prop!
-          props[name] = ctx.formatExpression(value);
-        }
-      }
-    }
-
-    let key = node.getAttribute("t-key");
-    if (key) {
-      key = ctx.formatExpression(key);
-    }
-
-    // computing the props string representing the props object
-    let propStr = Object.keys(props)
-      .map(k => k + ":" + props[k])
-      .join(",");
-    let dummyID = ctx.generateID();
-    let defID = ctx.generateID();
-    let widgetID = ctx.generateID();
-    let keyID = key && ctx.generateID();
-    if (key) {
-      // we bind a variable to the key (could be a complex expression, so we
-      // want to evaluate it only once)
-      ctx.addLine(`let key${keyID} = ${key};`);
-    }
-    ctx.addLine(`let def${defID};`);
-    let templateID = key
-      ? `key${keyID}`
-      : ctx.inLoop
-      ? `String(-${widgetID} - i)`
-      : String(widgetID);
-
-    let ref = node.getAttribute("t-ref");
-    let refExpr = "";
-    let refKey: string = "";
-    if (ref) {
-      refKey = `ref${ctx.generateID()}`;
-      ctx.addLine(`const ${refKey} = ${ctx.interpolate(ref)};`);
-      refExpr = `context.refs[${refKey}] = w${widgetID};`;
-    }
-    let transitionsInsertCode = "";
-    if (transition) {
-      transitionsInsertCode = `utils.transitionInsert(vn, '${transition}');`;
-    }
-    let finalizeWidgetCode = `w${widgetID}.${
-      keepAlive ? "unmount" : "destroy"
-    }();`;
-    if (ref && !keepAlive) {
-      finalizeWidgetCode += `delete context.refs[${refKey}];`;
-    }
-    if (transition) {
-      finalizeWidgetCode = `let finalize = () => {
-          ${finalizeWidgetCode}
-        };
-        utils.transitionRemove(vn, '${transition}', finalize);`;
-    }
-
-    let createHook = "";
-    let classAttr = node.getAttribute("class");
-    let tattClass = node.getAttribute("t-att-class");
-    let styleAttr = node.getAttribute("style");
-    let tattStyle = node.getAttribute("t-att-style");
-    if (tattStyle) {
-      const attVar = `_${ctx.generateID()}`;
-      ctx.addLine(`const ${attVar} = ${ctx.formatExpression(tattStyle)};`);
-      tattStyle = attVar;
-    }
-    let updateClassCode = "";
-    if (classAttr || tattClass || styleAttr || tattStyle || events.length) {
-      let classCode = "";
-      if (classAttr) {
-        classCode =
-          classAttr
-            .split(" ")
-            .map(c => `vn.elm.classList.add('${c}')`)
-            .join(";") + ";";
-      }
-      if (tattClass) {
-        const attVar = `_${ctx.generateID()}`;
-        ctx.addLine(`const ${attVar} = ${ctx.formatExpression(tattClass)};`);
-        classCode = `for (let k in ${attVar}) {
-              if (${attVar}[k]) {
-                  vn.elm.classList.add(k);
-              }
-          }`;
-        updateClassCode = `let cl=w${widgetID}.el.classList;for (let k in ${attVar}) {if (${attVar}[k]) {cl.add(k)} else {cl.remove(k)}}`;
-      }
-      let eventsCode = events
-        .map(function([eventName, mods, handlerName, extraArgs]) {
-          let params = extraArgs
-            ? `owner, ${ctx.formatExpression(extraArgs)}`
-            : "owner";
-          let handler;
-          if (mods.length > 0) {
-            handler = `function (e) {`;
-            handler += mods
-              .map(function(mod) {
-                return T_WIDGET_MODS_CODE[mod];
-              })
-              .join("");
-            handler += `owner['${handlerName}'].call(${params}, e);}`;
-          } else {
-            handler = `owner['${handlerName}'].bind(${params})`;
-          }
-          return `vn.elm.addEventListener('${eventName}', ${handler});`;
-        })
-        .join("");
-      const styleExpr = tattStyle || (styleAttr ? `'${styleAttr}'` : false);
-      const styleCode = styleExpr ? `vn.elm.style = ${styleExpr};` : "";
-      createHook = `vnode.data.hook = {create(_, vn){${classCode}${styleCode}${eventsCode}}};`;
-    }
-
-    ctx.addLine(
-      `let w${widgetID} = ${templateID} in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[${templateID}]] : false;`
-    );
-    ctx.addLine(`let _${dummyID}_index = c${ctx.parentNode}.length;`);
-    if (async) {
-      ctx.addLine(`const patchQueue${widgetID} = [];`);
-      ctx.addLine(
-        `c${
-          ctx.parentNode
-        }.push(w${widgetID} && w${widgetID}.__owl__.pvnode || null);`
-      );
-    } else {
-      ctx.addLine(`c${ctx.parentNode}.push(null);`);
-    }
-    ctx.addLine(`let props${widgetID} = {${propStr}};`);
-    ctx.addIf(
-      `w${widgetID} && w${widgetID}.__owl__.renderPromise && !w${widgetID}.__owl__.vnode`
-    );
-    ctx.addIf(
-      `utils.shallowEqual(props${widgetID}, w${widgetID}.__owl__.renderProps)`
-    );
-    ctx.addLine(`def${defID} = w${widgetID}.__owl__.renderPromise;`);
-    ctx.addElse();
-    ctx.addLine(`w${widgetID}.destroy();`);
-    ctx.addLine(`w${widgetID} = false;`);
-    ctx.closeIf();
-    ctx.closeIf();
-
-    ctx.addIf(`!w${widgetID}`);
-    // new widget
-    ctx.addLine(`let widgetKey${widgetID} = ${ctx.interpolate(value)};`);
-    ctx.addLine(
-      `let W${widgetID} = context.widgets && context.widgets[widgetKey${widgetID}] || QWeb.widgets[widgetKey${widgetID}];`
-    );
-
-    // maybe only do this in dev mode...
-    ctx.addLine(
-      `if (!W${widgetID}) {throw new Error('Cannot find the definition of widget "' + widgetKey${widgetID} + '"')}`
-    );
-    ctx.addLine(`w${widgetID} = new W${widgetID}(owner, props${widgetID});`);
-    ctx.addLine(
-      `context.__owl__.cmap[${templateID}] = w${widgetID}.__owl__.id;`
-    );
-
-    // SLOTS
-    if (node.childElementCount) {
-      const clone = <Element>node.cloneNode(true);
-      const slotNodes = clone.querySelectorAll("[t-set]");
-      const slotId = qweb.nextSlotId++;
-      ctx.addLine(`w${widgetID}.__owl__.slotId = ${slotId};`);
-      if (slotNodes.length) {
-        for (let i = 0, length = slotNodes.length; i < length; i++) {
-          const slotNode = slotNodes[i];
-          slotNode.parentElement!.removeChild(slotNode);
-          const key = slotNode.getAttribute("t-set")!;
-          slotNode.removeAttribute("t-set");
-          const slotFn = qweb._compile(`slot_${key}_template`, slotNode);
-          qweb.slots[`${slotId}_${key}`] = slotFn.bind(qweb);
-        }
-      }
-      if (clone.childElementCount) {
-        const content = clone.children[0];
-        const slotFn = qweb._compile(`slot_default_template`, content);
-        qweb.slots[`${slotId}_default`] = slotFn.bind(qweb);
-      }
-    }
-
-    ctx.addLine(`def${defID} = w${widgetID}._prepare();`);
-    // hack: specify empty remove hook to prevent the node from being removed from the DOM
-    ctx.addLine(
-      `def${defID} = def${defID}.then(vnode=>{${createHook}let pvnode=h(vnode.sel, {key: ${templateID}, hook: {insert(vn) {let nvn=w${widgetID}._mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;${refExpr}${transitionsInsertCode}},remove() {},destroy(vn) {${finalizeWidgetCode}}}});c${
-        ctx.parentNode
-      }[_${dummyID}_index]=pvnode;w${widgetID}.__owl__.pvnode = pvnode;});`
-    );
-
-    ctx.addElse();
-    // need to update widget
-    const patchQueueCode = async ? `patchQueue${widgetID}` : "extra.patchQueue";
-    ctx.addLine(
-      `def${defID} = def${defID} || w${widgetID}._updateProps(props${widgetID}, extra.forceUpdate, ${patchQueueCode});`
-    );
-    let keepAliveCode = "";
-    if (keepAlive) {
-      keepAliveCode = `pvnode.data.hook.insert = vn => {vn.elm.parentNode.replaceChild(w${widgetID}.el,vn.elm);vn.elm=w${widgetID}.el;w${widgetID}._remount();};`;
-    }
-    ctx.addLine(
-      `def${defID} = def${defID}.then(()=>{if (w${widgetID}.__owl__.isDestroyed) {return};${
-        tattStyle ? `w${widgetID}.el.style=${tattStyle};` : ""
-      }${updateClassCode}let pvnode=w${widgetID}.__owl__.pvnode;${keepAliveCode}c${
-        ctx.parentNode
-      }[_${dummyID}_index]=pvnode;});`
-    );
-    ctx.closeIf();
-
-    if (async) {
-      ctx.addLine(
-        `def${defID}.then(w${widgetID}._applyPatchQueue.bind(w${widgetID}, patchQueue${widgetID}));`
-      );
-    } else {
-      ctx.addLine(`extra.promises.push(def${defID});`);
-    }
-
-    if (
-      node.hasAttribute("t-if") ||
-      node.hasAttribute("t-else") ||
-      node.hasAttribute("t-elif")
-    ) {
-      ctx.closeIf();
-    }
-
-    return true;
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-mounted
-//------------------------------------------------------------------------------
-QWeb.addDirective({
-  name: "mounted",
-  priority: 97,
-  atNodeCreation({ ctx, fullName, value, nodeID, addNodeHook }) {
-    ctx.rootContext.shouldDefineOwner = true;
-    const eventName = fullName.slice(5);
-    if (!eventName) {
-      throw new Error("Missing event name with t-on directive");
-    }
-    let extraArgs;
-    let handler = value.replace(/\(.*\)/, function(args) {
-      extraArgs = args.slice(1, -1);
-      return "";
-    });
-    let error = `(function () {throw new Error('Missing handler \\'' + '${handler}' + \`\\' when evaluating template '${ctx.templateName.replace(
-      /`/g,
-      "'"
-    )}'\`)})()`;
-    if (extraArgs) {
-      ctx.addLine(
-        `extra.mountedHandlers[${nodeID}] = (context['${handler}'] || ${error}).bind(owner, ${ctx.formatExpression(
-          extraArgs
-        )});`
-      );
-    } else {
-      ctx.addLine(
-        `extra.mountedHandlers[${nodeID}] = extra.mountedHandlers[${nodeID}] || (context['${handler}'] || ${error}).bind(owner);`
-      );
-    }
-    addNodeHook(
-      "insert",
-      `if (context.__owl__.isMounted) { extra.mountedHandlers[${nodeID}](); }`
-    );
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-slot
-//------------------------------------------------------------------------------
-QWeb.addDirective({
-  name: "slot",
-  priority: 80,
-  atNodeEncounter({ ctx, value }): boolean {
-    const slotKey = ctx.generateID();
-    ctx.addLine(
-      `const slot${slotKey} = this.slots[context.__owl__.slotId + '_' + '${value}'];`
-    );
-    ctx.addLine(
-      `c${ctx.parentNode}.push(slot${slotKey}(context.__owl__.parent, extra));`
-    );
-    return true;
-  }
-});
-
-//------------------------------------------------------------------------------
-// t-model
-//------------------------------------------------------------------------------
-UTILS.toNumber = function(val: string): number | string {
-  const n = parseFloat(val);
-  return isNaN(n) ? val : n;
-};
-
-QWeb.addDirective({
-  name: "model",
-  priority: 42,
-  atNodeCreation({ ctx, nodeID, value, node, fullName }) {
-    const type = node.getAttribute("type");
-    let handler;
-    let event = fullName.includes(".lazy") ? "change" : "input";
-    if (node.tagName === "select") {
-      ctx.addLine(`p${nodeID}.props = {value: context.state['${value}']};`);
-      event = "change";
-      handler = `(ev) => {context.state['${value}'] = ev.target.value}`;
-    } else if (type === "checkbox") {
-      ctx.addLine(`p${nodeID}.props = {checked: context.state['${value}']};`);
-      handler = `(ev) => {context.state['${value}'] = ev.target.checked}`;
-    } else if (type === "radio") {
-      const nodeValue = node.getAttribute("value")!;
-      ctx.addLine(
-        `p${nodeID}.props = {checked:context.state['${value}'] === '${nodeValue}'};`
-      );
-      handler = `(ev) => {context.state['${value}'] = ev.target.value}`;
-      event = "click";
-    } else {
-      ctx.addLine(`p${nodeID}.props = {value: context.state['${value}']};`);
-      const trimCode = fullName.includes(".trim") ? ".trim()" : "";
-      let valueCode = `ev.target.value${trimCode}`;
-      if (fullName.includes(".number")) {
-        ctx.rootContext.shouldDefineUtils = true;
-        valueCode = `utils.toNumber(${valueCode})`;
-      }
-      handler = `(ev) => {context.state['${value}'] = ${valueCode}}`;
-    }
-    ctx.addLine(
-      `extra.handlers['${event}' + ${nodeID}] = extra.handlers['${event}' + ${nodeID}] || (${handler});`
-    );
-    ctx.addLine(
-      `p${nodeID}.on['${event}'] = extra.handlers['${event}' + ${nodeID}];`
-    );
-  }
-});

src/router/link.ts

@@ -0,0 +1,48 @@
+import { Component } from "../component/component";
+import { xml } from "../tags";
+import { Destination, RouterEnv } from "./router";
+
+type Props = Destination;
+
+export class Link<Env extends RouterEnv> extends Component<Env, Props> {
+  static template = xml`
+    <a  t-att-class="{'router-link-active': isActive }"
+        t-att-href="href"
+        t-on-click="navigate">
+        <t t-slot="default"/>
+    </a>
+  `;
+
+  href: string = this.env.router.destToPath(this.props);
+
+  async willUpdateProps(nextProps) {
+    this.href = this.env.router.destToPath(nextProps);
+  }
+
+  get isActive() {
+    if (this.env.router.mode === "hash") {
+      return (<any>document.location).hash === this.href;
+    }
+    return (<any>document.location).pathname === this.href;
+  }
+
+  navigate(ev) {
+    // don't redirect with control keys
+    if (ev.metaKey || ev.altKey || ev.ctrlKey || ev.shiftKey) {
+      return;
+    }
+    // don't redirect on right click
+    if (ev.button !== undefined && ev.button !== 0) {
+      return;
+    }
+    // don't redirect if `target="_blank"`
+    if (ev.currentTarget && ev.currentTarget.getAttribute) {
+      const target = ev.currentTarget.getAttribute("target");
+      if (/\b_blank\b/i.test(target)) {
+        return;
+      }
+    }
+    ev.preventDefault();
+    this.env.router.navigate(this.props);
+  }
+}

src/router/route_component.ts

@@ -0,0 +1,18 @@
+import { Component } from "../component/component";
+import { xml } from "../tags";
+
+export class RouteComponent extends Component<any, {}> {
+  static template = xml`
+    <t>
+        <t
+            t-if="routeComponent"
+            t-component="routeComponent"
+            t-key="env.router.currentRouteName"
+            t-props="env.router.currentParams" />
+    </t>
+  `;
+
+  get routeComponent(): any {
+    return this.env.router.currentRoute && this.env.router.currentRoute.component;
+  }
+}

src/router/router.ts

@@ -0,0 +1,275 @@
+import { Env } from "../component/component";
+import { QWeb } from "../qweb/index";
+import { shallowEqual } from "../utils";
+
+type NavigationGuard = (info: {
+  env: Env;
+  to: Route | null;
+  from: Route | null;
+}) => boolean | Destination;
+
+export interface Route {
+  name: string;
+  path: string;
+  component?: any;
+  redirect?: Destination;
+  params: string[];
+  beforeRouteEnter?: NavigationGuard;
+}
+
+export type RouteParams = { [key: string]: string | number };
+
+export interface RouterEnv extends Env {
+  router: Router;
+}
+
+export interface Destination {
+  path?: string;
+  to?: string;
+  params?: RouteParams;
+}
+
+interface PositiveMatchResult {
+  type: "match";
+  route: Route;
+  params: RouteParams;
+}
+
+interface NegativeMatchResult {
+  type: "nomatch";
+}
+
+interface CancelledMatch {
+  type: "cancelled";
+}
+
+type MatchResult = PositiveMatchResult | NegativeMatchResult | CancelledMatch;
+
+interface Options {
+  mode: Router["mode"];
+}
+
+const paramRegexp = /\{\{(.*?)\}\}/;
+
+export class Router {
+  currentRoute: Route | null = null;
+  currentParams: RouteParams | null = null;
+  mode: "history" | "hash";
+
+  routes: { [id: string]: Route };
+  routeIds: string[];
+  env: RouterEnv;
+
+  constructor(env: Env, routes: Partial<Route>[], options: Options = { mode: "history" }) {
+    env.router = this;
+    this.mode = options.mode;
+    this.env = env as RouterEnv;
+
+    this.routes = {};
+    this.routeIds = [];
+    let nextId = 1;
+    for (let partialRoute of routes) {
+      if (!partialRoute.name) {
+        partialRoute.name = "__route__" + nextId++;
+      }
+      if (partialRoute.component) {
+        QWeb.registerComponent("__component__" + partialRoute.name, partialRoute.component);
+      }
+      if (partialRoute.redirect) {
+        this.validateDestination(partialRoute.redirect);
+      }
+      partialRoute.params = partialRoute.path ? findParams(partialRoute.path) : [];
+      this.routes[partialRoute.name] = partialRoute as Route;
+      this.routeIds.push(partialRoute.name);
+    }
+  }
+
+  //--------------------------------------------------------------------------
+  // Public API
+  //--------------------------------------------------------------------------
+
+  async start() {
+    (this as any)._listener = ev => this._navigate(this.currentPath(), ev);
+    window.addEventListener("popstate", (this as any)._listener);
+    if (this.mode === "hash") {
+      window.addEventListener("hashchange", (this as any)._listener);
+    }
+    const result = await this.matchAndApplyRules(this.currentPath());
+    if (result.type === "match") {
+      this.currentRoute = result.route;
+      this.currentParams = result.params;
+      const currentPath = this.routeToPath(result.route, result.params);
+      if (currentPath !== this.currentPath()) {
+        this.setUrlFromPath(currentPath);
+      }
+    }
+  }
+
+  async navigate(to: Destination): Promise<boolean> {
+    const path = this.destToPath(to);
+    return this._navigate(path);
+  }
+  async _navigate(path: string, ev?: any): Promise<boolean> {
+    const initialName = this.currentRouteName;
+    const initialParams = this.currentParams;
+    const result = await this.matchAndApplyRules(path);
+    if (result.type === "match") {
+      const finalPath = this.routeToPath(result.route, result.params);
+      const isPopStateEvent = ev && ev instanceof PopStateEvent;
+      if (!isPopStateEvent) {
+        this.setUrlFromPath(finalPath);
+      }
+      this.currentRoute = result.route;
+      this.currentParams = result.params;
+    } else if (result.type === "nomatch") {
+      this.currentRoute = null;
+      this.currentParams = null;
+    }
+    const didChange =
+      this.currentRouteName !== initialName || !shallowEqual(this.currentParams, initialParams);
+    if (didChange) {
+      this.env.qweb.forceUpdate();
+      return true;
+    }
+    return false;
+  }
+
+  destToPath(dest: Destination): string {
+    this.validateDestination(dest);
+    return dest.path || this.routeToPath(this.routes[dest.to!], dest.params!);
+  }
+
+  get currentRouteName(): string | null {
+    return this.currentRoute && this.currentRoute.name;
+  }
+
+  //--------------------------------------------------------------------------
+  // Private helpers
+  //--------------------------------------------------------------------------
+
+  private setUrlFromPath(path: string) {
+    const separator = this.mode === "hash" ? "/" : "";
+    const url = location.origin + separator + path;
+    if (url !== window.location.href) {
+      window.history.pushState({}, path, url);
+    }
+  }
+
+  private validateDestination(dest: Destination) {
+    if ((!dest.path && !dest.to) || (dest.path && dest.to)) {
+      throw new Error(`Invalid destination: ${JSON.stringify(dest)}`);
+    }
+  }
+
+  private routeToPath(route: Route, params: RouteParams): string {
+    const path = route.path;
+    const parts = path.split("/");
+    const l = parts.length;
+    for (let i = 0; i < l; i++) {
+      const part = parts[i];
+      const match = part.match(paramRegexp);
+      if (match) {
+        const key = match[1].split(".")[0];
+        parts[i] = <string>params[key];
+      }
+    }
+    const prefix = this.mode === "hash" ? "#" : "";
+    return prefix + parts.join("/");
+  }
+
+  private currentPath(): string {
+    let result = this.mode === "history" ? window.location.pathname : window.location.hash.slice(1);
+    return result || "/";
+  }
+
+  private match(path: string): MatchResult {
+    for (let routeId of this.routeIds) {
+      let route = this.routes[routeId];
+      let params = this.getRouteParams(route, path);
+      if (params) {
+        return {
+          type: "match",
+          route: route,
+          params: params
+        };
+      }
+    }
+    return { type: "nomatch" };
+  }
+
+  private async matchAndApplyRules(path: string): Promise<MatchResult> {
+    const result = this.match(path);
+    if (result.type === "match") {
+      return this.applyRules(result);
+    }
+    return result;
+  }
+
+  private async applyRules(matchResult: PositiveMatchResult): Promise<MatchResult> {
+    const route = matchResult.route;
+    if (route.redirect) {
+      const path = this.destToPath(route.redirect);
+      return this.matchAndApplyRules(path);
+    }
+    if (route.beforeRouteEnter) {
+      const result = await route.beforeRouteEnter({
+        env: this.env,
+        from: this.currentRoute,
+        to: route
+      });
+      if (result === false) {
+        return { type: "cancelled" };
+      } else if (result !== true) {
+        // we want to navigate to another destination
+        const path = this.destToPath(result);
+        return this.matchAndApplyRules(path);
+      }
+    }
+
+    return matchResult;
+  }
+
+  private getRouteParams(route: Route, path: string): RouteParams | false {
+    if (route.path === "*") {
+      return {};
+    }
+    if (path.startsWith("#")) {
+      path = path.slice(1);
+    }
+    const descrParts = route.path.split("/");
+    const targetParts = path.split("/");
+    const l = descrParts.length;
+    if (l !== targetParts.length) {
+      return false;
+    }
+    const result = {};
+    for (let i = 0; i < l; i++) {
+      const descr = descrParts[i];
+      let target: string | number = targetParts[i];
+      const match = descr.match(paramRegexp);
+      if (match) {
+        const [key, suffix] = match[1].split(".");
+        if (suffix === "number") {
+          target = parseInt(target, 10);
+        }
+        result[key] = target;
+      } else if (descr !== target) {
+        return false;
+      }
+    }
+    return result;
+  }
+}
+
+function findParams(str: string): string[] {
+  const globalParamRegexp = /\{\{(.*?)\}\}/g;
+  const result: string[] = [];
+  let m;
+  do {
+    m = globalParamRegexp.exec(str);
+    if (m) {
+      result.push(m[1].split(".")[0]);
+    }
+  } while (m);
+  return result;
+}

src/store.ts

@@ -1,17 +1,20 @@
-import { Component, Env } from "./component";
-import { EventBus } from "./event_bus";
-import { Observer } from "./observer";
+import { Component } from "./component/component";
+import { Env } from "./component/component";
+import { Context, useContextWithCB } from "./context";
+import { onWillUpdateProps } from "./hooks";
 
 /**
  * Owl Store
  *
  * We have here:
  * - a Store class
- * - a connect function
+ * - useStore hook
+ * - useDispatch hook
+ * - useGetters hook
  *
  * The Owl store is our answer to the problem of managing complex state across
  * components. The main idea is that the store owns some state, allow external
- * code to modify it through actions/mutations, and for each state changes,
+ * code to modify it through actions, and for each state changes,
  * connected component will be notified, and updated if necessary.
  *
  * Note that this code is partly inspired by VueX and React/Redux
@@ -21,278 +24,119 @@ import { Observer } from "./observer";
 // Store Definition
 //------------------------------------------------------------------------------
 
-type Mutation = ({ state, commit, getters }, payload: any) => void;
-type Action = ({ commit, state, dispatch, env, getters }, payload: any) => void;
-type Getter = ({ state, getters }, payload) => any;
+export type Action = ({ state, dispatch, env, getters }, ...payload: any) => any;
+export type Getter = ({ state: any, getters }, payload?) => any;
 
 interface StoreConfig {
   env?: Env;
   state?: any;
   actions?: { [name: string]: Action };
   getters?: { [name: string]: Getter };
-  mutations?: { [name: string]: Mutation };
 }
 
-interface StoreOption {
-  debug?: boolean;
-}
-
-export class Store extends EventBus {
-  state: any;
+export class Store extends Context {
   actions: any;
-  mutations: any;
-  _commitLevel: number = 0;
-  history: any[] = [];
-  debug: boolean;
   env: any;
-  observer: Observer;
   getters: { [name: string]: (payload?) => any };
-  _gettersCache: { [name: string]: {} };
+  updateFunctions: { [key: number]: (() => boolean)[] };
 
-  constructor(config: StoreConfig, options: StoreOption = {}) {
-    super();
-    this.debug = options.debug || false;
-    this.state = config.state || {};
+  constructor(config: StoreConfig) {
+    super(config.state);
     this.actions = config.actions;
-    this.mutations = config.mutations;
     this.env = config.env;
-    this.observer = new Observer();
-    this.observer.notifyCB = () => {
-      this._gettersCache = {};
-      this.trigger("update");
-    };
-    this.observer.allowMutations = false;
-    this.observer.observe(this.state);
     this.getters = {};
-    this._gettersCache = {};
-
-    if (this.debug) {
-      this.history.push({ state: this.state });
-    }
-
-    const cTypes = ["undefined", "number", "string"];
-    for (let entry of Object.entries(config.getters || {})) {
-      const name: string = entry[0];
-      const func: (...any) => any = entry[1];
-      this.getters[name] = payload => {
-        if (this._commitLevel === 0 && cTypes.indexOf(typeof payload) >= 0) {
-          this._gettersCache[name] = this._gettersCache[name] || {};
-          this._gettersCache[name][payload] =
-            this._gettersCache[name][payload] ||
-            func({ state: this.state, getters: this.getters }, payload);
-          return this._gettersCache[name][payload];
-        }
-        return func({ state: this.state, getters: this.getters }, payload);
+    this.updateFunctions = [];
+    if (config.getters) {
+      const firstArg = {
+        state: this.state,
+        getters: this.getters
       };
+      for (let g in config.getters) {
+        this.getters[g] = config.getters[g].bind(this, firstArg);
+      }
     }
   }
 
-  dispatch(action: string, payload?: any): Promise<void> | void {
+  dispatch(action: string, ...payload: any): Promise<void> | void {
     if (!this.actions[action]) {
       throw new Error(`[Error] action ${action} is undefined`);
     }
     const result = this.actions[action](
       {
-        commit: this.commit.bind(this),
         dispatch: this.dispatch.bind(this),
         env: this.env,
         state: this.state,
         getters: this.getters
       },
-      payload
+      ...payload
     );
-    if (result instanceof Promise) {
-      return new Promise((resolve, reject) => {
-        result.then(() => resolve());
-        result.catch(reject);
-      });
-    }
-  }
-
-  commit(type: string, payload?: any): any {
-    if (!this.mutations[type]) {
-      throw new Error(`[Error] mutation ${type} is undefined`);
-    }
-    this._commitLevel++;
-    this.observer.allowMutations = true;
-
-    const res = this.mutations[type].call(
-      null,
-      {
-        commit: this.commit.bind(this),
-        state: this.state,
-        getters: this.getters
-      },
-      payload
-    );
-
-    if (this._commitLevel === 1) {
-      this.observer.allowMutations = false;
-      if (this.debug) {
-        this.history.push({
-          state: this.state,
-          mutation: type,
-          payload: payload
-        });
-      }
-    }
-    this._commitLevel--;
-    return res;
+    return result;
   }
 }
 
-//------------------------------------------------------------------------------
-// Connect function
-//------------------------------------------------------------------------------
+interface SelectorOptions {
+  store?: Store;
+  isEqual?: (a: any, b: any) => boolean;
+}
 
-function revNumber<T extends Object>(o: T): number {
-  if (o !== null && typeof o === "object" && (<any>o).__owl__) {
-    return (<any>o).__owl__.rev;
+const isStrictEqual = (a, b) => a === b;
+
+export function useStore(selector, options: SelectorOptions = {}): any {
+  const component: Component<any, any> = Component.current!;
+  const store = options.store || (component.env.store as Store);
+  let result = selector(store.state, component.props);
+  const hashFn = store.observer.deepRevNumber.bind(store.observer);
+  let revNumber = hashFn(result) || result;
+  const isEqual = options.isEqual || isStrictEqual;
+  if (!store.updateFunctions[component.__owl__.id]) {
+    store.updateFunctions[component.__owl__.id] = [];
   }
-  return 0;
+  const updateFunctions = store.updateFunctions[component.__owl__.id];
+  updateFunctions.push(function(): boolean {
+    const oldResult = result;
+    result = selector(store!.state, component.props);
+    const newRevNumber = hashFn(result);
+    if (
+      (newRevNumber > 0 && revNumber !== newRevNumber) ||
+      (newRevNumber === 0 && !isEqual(oldResult, result))
+    ) {
+      revNumber = newRevNumber;
+      return true;
+    }
+    return false;
+  });
+
+  useContextWithCB(store, component, function(): Promise<void> | void {
+    let shouldRender = false;
+    updateFunctions.forEach(function(updateFn) {
+      shouldRender = updateFn() || shouldRender;
+    });
+    if (shouldRender) {
+      return component.render();
+    }
+  });
+  onWillUpdateProps(props => {
+    // FIXME: only do that if not keepalive + do it in destroy in that case
+    delete store.updateFunctions[component.__owl__.id];
+    result = selector(store.state, props);
+  });
+  return new Proxy(result, {
+    get(target, k) {
+      return result[k];
+    },
+    set(target, k, v) {
+      result[k] = v;
+      return true;
+    }
+  });
 }
 
-function deepRevNumber<T extends Object>(o: T): number {
-  if (o !== null && typeof o === "object" && (<any>o).__owl__) {
-    return (<any>o).__owl__.deepRev;
-  }
-  return 0;
+export function useDispatch(store?: Store): Store["dispatch"] {
+  store = store || (Component.current!.env.store as Store);
+  return store.dispatch.bind(store);
 }
 
-type Constructor<T> = new (...args: any[]) => T;
-interface EnvWithStore extends Env {
-  store: Store;
-}
-type HashFunction = (a: any, b: any) => number;
-interface StoreOptions {
-  getStore?(Env): Store;
-  hashFunction?: HashFunction;
-  deep?: boolean;
-}
-
-let nextID = 1;
-
-export function connect<E extends EnvWithStore, P, S>(
-  Comp: Constructor<Component<E, P, S>>,
-  mapStoreToProps,
-  options: StoreOptions = <StoreOptions>{}
-) {
-  let hashFunction = options.hashFunction || null;
-  const getStore = options.getStore || (env => env.store);
-
-  if (!hashFunction) {
-    let deep = "deep" in options ? options.deep : true;
-    let defaultRevFunction = deep ? deepRevNumber : revNumber;
-    hashFunction = function({ storeProps }, options) {
-      const { currentStoreProps } = options;
-      if ("__owl__" in storeProps) {
-        return defaultRevFunction(storeProps);
-      }
-      let hash = 0;
-      for (let key in storeProps) {
-        const val = storeProps[key];
-        const hashVal = defaultRevFunction(val);
-        if (hashVal === 0) {
-          if (val !== currentStoreProps[key]) {
-            options.didChange = true;
-          }
-        } else {
-          hash += hashVal;
-        }
-      }
-      return hash;
-    };
-  }
-
-  const Result = class extends Comp {
-    constructor(parent, props?: any) {
-      const env = parent instanceof Component ? parent.env : parent;
-      const store = getStore(env);
-      const ownProps = Object.assign({}, props || {});
-      const storeProps = mapStoreToProps(store.state, ownProps, store.getters);
-      const mergedProps = Object.assign({}, props || {}, storeProps);
-      super(parent, mergedProps);
-      (<any>this.__owl__).ownProps = ownProps;
-      (<any>this.__owl__).currentStoreProps = storeProps;
-      (<any>this.__owl__).store = store;
-      (<any>this.__owl__).storeHash = (<HashFunction>hashFunction)(
-        {
-          state: store.state,
-          storeProps: storeProps,
-          revNumber,
-          deepRevNumber
-        },
-        {
-          currentStoreProps: storeProps
-        }
-      );
-    }
-    /**
-     * We do not use the mounted hook here for a subtle reason: we want the
-     * updates to be called for the parents before the children.  However,
-     * if we use the mounted hook, this will be done in the reverse order.
-     */
-    _callMounted() {
-      (<any>this.__owl__).store.on("update", this, this._checkUpdate);
-      super._callMounted();
-    }
-    willUnmount() {
-      (<any>this.__owl__).store.off("update", this);
-      super.willUnmount();
-    }
-
-    _checkUpdate() {
-      const ownProps = (<any>this.__owl__).ownProps;
-      const storeProps = mapStoreToProps(
-        (<any>this.__owl__).store.state,
-        ownProps,
-        (<any>this.__owl__).store.getters
-      );
-      const options: any = {
-        currentStoreProps: (<any>this.__owl__).currentStoreProps
-      };
-      const storeHash = (<HashFunction>hashFunction)(
-        {
-          state: (<any>this.__owl__).store.state,
-          storeProps: storeProps,
-          revNumber,
-          deepRevNumber
-        },
-        options
-      );
-      let didChange = options.didChange;
-      if (storeHash !== (<any>this.__owl__).storeHash) {
-        didChange = true;
-        (<any>this.__owl__).storeHash = storeHash;
-      }
-      if (didChange) {
-        (<any>this.__owl__).currentStoreProps = storeProps;
-        this._updateProps(ownProps, false);
-      }
-    }
-    _updateProps(nextProps, forceUpdate, patchQueue?: any[]) {
-      if ((<any>this.__owl__).ownProps !== nextProps) {
-        (<any>this.__owl__).currentStoreProps = mapStoreToProps(
-          (<any>this.__owl__).store.state,
-          nextProps,
-          (<any>this.__owl__).store.getters
-        );
-      }
-      (<any>this.__owl__).ownProps = nextProps;
-      const mergedProps = Object.assign(
-        {},
-        nextProps,
-        (<any>this.__owl__).currentStoreProps
-      );
-      return super._updateProps(mergedProps, forceUpdate, patchQueue);
-    }
-  };
-
-  // we assign here a unique name to the resulting anonymous class.
-  // this is necessary for Owl to be able to properly deduce templates.
-  // Otherwise, all connected components would have the same name, and then
-  // each component after the first will necessarily have the same template.
-  let name = `ConnectedComponent${nextID++}`;
-  Object.defineProperty(Result, "name", { value: name });
-  return Result;
+export function useGetters(store?: Store): Store["getters"] {
+  store = store || (Component.current!.env.store as Store);
+  return store.getters;
 }

src/tags.ts

@@ -0,0 +1,27 @@
+import { QWeb } from "./qweb/index";
+
+/**
+ * Owl Tags
+ *
+ * We have here a (very) small collection of tag functions:
+ *
+ * - xml
+ *
+ * The plan is to add a few other tags such as css, globalcss.
+ */
+
+/**
+ * XML tag helper for defining templates.  With this, one can simply define
+ * an inline template with just the template xml:
+ * ```js
+ *   class A extends Component {
+ *     static template = xml`<div>some template</div>`;
+ *   }
+ * ```
+ */
+export function xml(strings, ...args) {
+  const name = `__template__${QWeb.nextId++}`;
+  const value = String.raw(strings, ...args);
+  QWeb.registerTemplate(name, value);
+  return name;
+}

src/utils.ts

@@ -5,19 +5,19 @@
  *
  * - whenReady
  * - loadJS
- * - loadTemplates
+ * - loadFile
  * - escape
  * - debounce
  */
 
-export function whenReady(fn) {
+export function whenReady(fn?: any) {
   return new Promise(function(resolve) {
     if (document.readyState !== "loading") {
       resolve();
     } else {
       document.addEventListener("DOMContentLoaded", resolve, false);
     }
-  }).then(fn || function () {});
+  }).then(fn || function() {});
 }
 
 const loadedScripts: { [key: string]: Promise<void> } = {};
@@ -43,14 +43,12 @@ export function loadJS(url: string): Promise<void> {
   return promise;
 }
 
-export async function loadTemplates(url: string): Promise<string> {
+export async function loadFile(url: string): Promise<string> {
   const result = await fetch(url);
   if (!result.ok) {
     throw new Error("Error while fetching xml templates");
   }
-  let templates = await result.text();
-  templates = templates.replace(/<!--[\s\S]*?-->/g, "");
-  return templates;
+  return await result.text();
 }
 
 export function escape(str: string | number | undefined): string {
@@ -76,11 +74,7 @@ export function escape(str: string | number | undefined): string {
  *
  * Inspired by https://davidwalsh.name/javascript-debounce-function
  */
-export function debounce(
-  func: Function,
-  wait: number,
-  immediate?: boolean
-): Function {
+export function debounce(func: Function, wait: number, immediate?: boolean): Function {
   let timeout;
   return function(this: any) {
     const context = this;
@@ -99,3 +93,12 @@ export function debounce(
     }
   };
 }
+
+export function shallowEqual(p1, p2): boolean {
+  for (let k in p1) {
+    if (p1[k] !== p2[k]) {
+      return false;
+    }
+  }
+  return true;
+}

src/vdom/html_to_vdom.ts

@@ -0,0 +1,29 @@
+import { VNode, h } from "./vdom";
+
+const parser = new DOMParser();
+
+export function htmlToVDOM(html: string): VNode[] {
+  const doc = parser.parseFromString(html, "text/html");
+  const result: VNode[] = [];
+  for (let child of doc.body.childNodes) {
+    result.push(htmlToVNode(child));
+  }
+  return result;
+}
+
+function htmlToVNode(node: ChildNode): VNode {
+  if (!(node instanceof Element)) {
+    return { text: node.textContent! } as VNode;
+  }
+  const attrs = {};
+  for (let attr of node.attributes) {
+    attrs[attr.name] = attr.textContent;
+  }
+  const children: VNode[] = [];
+  if (node.hasChildNodes) {
+    for (let c of node.childNodes) {
+      children.push(htmlToVNode(c));
+    }
+  }
+  return h((node as Element).tagName, { attrs }, children);
+}

src/vdom/index.ts

@@ -0,0 +1,9 @@
+import { attrsModule, classModule, eventListenersModule, propsModule } from "./modules";
+import { init } from "./vdom";
+//------------------------------------------------------------------------------
+// patch
+//------------------------------------------------------------------------------
+
+export { h, VNode } from "./vdom";
+
+export const patch = init([eventListenersModule, attrsModule, propsModule, classModule]);

src/vdom/modules.ts

@@ -0,0 +1,234 @@
+import { Module, VNode, VNodeData } from "./vdom";
+
+//------------------------------------------------------------------------------
+// module/props.ts
+//------------------------------------------------------------------------------
+
+function updateProps(oldVnode: VNode, vnode: VNode): void {
+  var key: string,
+    cur: any,
+    old: any,
+    elm = vnode.elm,
+    oldProps = (oldVnode.data as VNodeData).props,
+    props = (vnode.data as VNodeData).props;
+
+  if (!oldProps && !props) return;
+  if (oldProps === props) return;
+  oldProps = oldProps || {};
+  props = props || {};
+
+  for (key in oldProps) {
+    if (!props[key]) {
+      delete (elm as any)[key];
+    }
+  }
+  for (key in props) {
+    cur = props[key];
+    old = oldProps[key];
+    if (old !== cur && (key !== "value" || (elm as any)[key] !== cur)) {
+      (elm as any)[key] = cur;
+    }
+  }
+}
+
+export const propsModule = {
+  create: updateProps,
+  update: updateProps
+} as Module;
+
+//------------------------------------------------------------------------------
+// module/eventlisteners.ts
+//------------------------------------------------------------------------------
+
+function invokeHandler(handler: any, vnode?: VNode, event?: Event): void {
+  if (typeof handler === "function") {
+    // call function handler
+    handler.call(vnode, event, vnode);
+  } else if (typeof handler === "object") {
+    // call handler with arguments
+    if (typeof handler[0] === "function") {
+      // special case for single argument for performance
+      if (handler.length === 2) {
+        handler[0].call(vnode, handler[1], event, vnode);
+      } else {
+        var args = handler.slice(1);
+        args.push(event);
+        args.push(vnode);
+        handler[0].apply(vnode, args);
+      }
+    } else {
+      // call multiple handlers
+      for (let i = 0, iLen = handler.length; i < iLen; i++) {
+        invokeHandler(handler[i], vnode, event);
+      }
+    }
+  }
+}
+
+function handleEvent(event: Event, vnode: VNode) {
+  var name = event.type,
+    on = (vnode.data as VNodeData).on;
+
+  // call event handler(s) if exists
+  if (on && on[name]) {
+    invokeHandler(on[name], vnode, event);
+  }
+}
+
+function createListener() {
+  return function handler(event: Event) {
+    handleEvent(event, (handler as any).vnode);
+  };
+}
+
+function updateEventListeners(oldVnode: VNode, vnode?: VNode): void {
+  var oldOn = (oldVnode.data as VNodeData).on,
+    oldListener = (oldVnode as any).listener,
+    oldElm: Element = oldVnode.elm as Element,
+    on = vnode && (vnode.data as VNodeData).on,
+    elm: Element = (vnode && vnode.elm) as Element,
+    name: string;
+
+  // optimization for reused immutable handlers
+  if (oldOn === on) {
+    return;
+  }
+
+  // remove existing listeners which no longer used
+  if (oldOn && oldListener) {
+    // if element changed or deleted we remove all existing listeners unconditionally
+    if (!on) {
+      for (name in oldOn) {
+        // remove listener if element was changed or existing listeners removed
+        oldElm.removeEventListener(name, oldListener, false);
+      }
+    } else {
+      for (name in oldOn) {
+        // remove listener if existing listener removed
+        if (!on[name]) {
+          oldElm.removeEventListener(name, oldListener, false);
+        }
+      }
+    }
+  }
+
+  // add new listeners which has not already attached
+  if (on) {
+    // reuse existing listener or create new
+    var listener = ((vnode as any).listener = (oldVnode as any).listener || createListener());
+    // update vnode for listener
+    listener.vnode = vnode;
+
+    // if element changed or added we add all needed listeners unconditionally
+    if (!oldOn) {
+      for (name in on) {
+        // add listener if element was changed or new listeners added
+        elm.addEventListener(name, listener, false);
+      }
+    } else {
+      for (name in on) {
+        // add listener if new listener added
+        if (!oldOn[name]) {
+          elm.addEventListener(name, listener, false);
+        }
+      }
+    }
+  }
+}
+
+export const eventListenersModule = {
+  create: updateEventListeners,
+  update: updateEventListeners,
+  destroy: updateEventListeners
+} as Module;
+
+//------------------------------------------------------------------------------
+// attributes.ts
+//------------------------------------------------------------------------------
+
+const xlinkNS = "http://www.w3.org/1999/xlink";
+const xmlNS = "http://www.w3.org/XML/1998/namespace";
+const colonChar = 58;
+const xChar = 120;
+
+function updateAttrs(oldVnode: VNode, vnode: VNode): void {
+  var key: string,
+    elm: Element = vnode.elm as Element,
+    oldAttrs = (oldVnode.data as VNodeData).attrs,
+    attrs = (vnode.data as VNodeData).attrs;
+
+  if (!oldAttrs && !attrs) return;
+  if (oldAttrs === attrs) return;
+  oldAttrs = oldAttrs || {};
+  attrs = attrs || {};
+
+  // update modified attributes, add new attributes
+  for (key in attrs) {
+    const cur = attrs[key];
+    const old = oldAttrs[key];
+    if (old !== cur) {
+      if (cur === true) {
+        elm.setAttribute(key, "");
+      } else if (cur === false) {
+        elm.removeAttribute(key);
+      } else {
+        if (key.charCodeAt(0) !== xChar) {
+          elm.setAttribute(key, cur);
+        } else if (key.charCodeAt(3) === colonChar) {
+          // Assume xml namespace
+          elm.setAttributeNS(xmlNS, key, cur);
+        } else if (key.charCodeAt(5) === colonChar) {
+          // Assume xlink namespace
+          elm.setAttributeNS(xlinkNS, key, cur);
+        } else {
+          elm.setAttribute(key, cur);
+        }
+      }
+    }
+  }
+  // remove removed attributes
+  // use `in` operator since the previous `for` iteration uses it (.i.e. add even attributes with undefined value)
+  // the other option is to remove all attributes with value == undefined
+  for (key in oldAttrs) {
+    if (!(key in attrs)) {
+      elm.removeAttribute(key);
+    }
+  }
+}
+
+export const attrsModule = {
+  create: updateAttrs,
+  update: updateAttrs
+} as Module;
+
+//------------------------------------------------------------------------------
+// class.ts
+//------------------------------------------------------------------------------
+function updateClass(oldVnode: VNode, vnode: VNode): void {
+  var cur: any,
+    name: string,
+    elm: Element,
+    oldClass = (oldVnode.data as VNodeData).class,
+    klass = (vnode.data as VNodeData).class;
+
+  if (!oldClass && !klass) return;
+  if (oldClass === klass) return;
+  oldClass = oldClass || {};
+  klass = klass || {};
+
+  elm = vnode.elm as Element;
+
+  for (name in oldClass) {
+    if (!klass[name]) {
+      elm.classList.remove(name);
+    }
+  }
+  for (name in klass) {
+    cur = klass[name];
+    if (cur !== oldClass[name]) {
+      (elm.classList as any)[cur ? "add" : "remove"](name);
+    }
+  }
+}
+
+export const classModule = { create: updateClass, update: updateClass } as Module;

src/vdom/vdom.ts

@@ -27,6 +27,21 @@ declare global {
   }
 }
 
+type Props = Record<string, any>;
+type Attrs = Record<string, string | number | boolean>;
+type On = { [N in keyof HTMLElementEventMap]?: (ev: HTMLElementEventMap[N]) => void } & {
+  [event: string]: EventListener;
+};
+
+export interface Module {
+  pre: PreHook;
+  create: CreateHook;
+  update: UpdateHook;
+  destroy: DestroyHook;
+  remove: RemoveHook;
+  post: PostHook;
+}
+
 //------------------------------------------------------------------------------
 // vnode.ts
 //------------------------------------------------------------------------------
@@ -41,7 +56,7 @@ export interface VNode {
   key: Key | undefined;
 }
 
-interface VNodeData {
+export interface VNodeData {
   props?: Props;
   attrs?: Attrs;
   on?: On;
@@ -59,7 +74,7 @@ function vnode(
   elm: Element | Text | undefined
 ): VNode {
   let key = data === undefined ? undefined : data.key;
-  return {sel, data, children, text, elm, key};
+  return { sel, data, children, text, elm, key };
 }
 
 //------------------------------------------------------------------------------
@@ -109,14 +124,7 @@ function createKeyToOldIdx(
   return map;
 }
 
-const hooks: (keyof Module)[] = [
-  "create",
-  "update",
-  "remove",
-  "destroy",
-  "pre",
-  "post"
-];
+const hooks: (keyof Module)[] = ["create", "update", "remove", "destroy", "pre", "post"];
 
 export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   let i: number,
@@ -138,13 +146,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   function emptyNodeAt(elm: Element) {
     const id = elm.id ? "#" + elm.id : "";
     const c = elm.className ? "." + elm.className.split(" ").join(".") : "";
-    return vnode(
-      api.tagName(elm).toLowerCase() + id + c,
-      {},
-      [],
-      undefined,
-      elm
-    );
+    return vnode(api.tagName(elm).toLowerCase() + id + c, {}, [], undefined, elm);
   }
 
   function createRmCb(childElm: Node, listeners: number) {
@@ -174,24 +176,11 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       }
       vnode.elm = api.createComment(vnode.text as string);
     } else if (sel !== undefined) {
-      // Parse selector
-      const hashIdx = sel.indexOf("#");
-      const dotIdx = sel.indexOf(".", hashIdx);
-      const hash = hashIdx > 0 ? hashIdx : sel.length;
-      const dot = dotIdx > 0 ? dotIdx : sel.length;
-      const tag =
-        hashIdx !== -1 || dotIdx !== -1
-          ? sel.slice(0, Math.min(hash, dot))
-          : sel;
       const elm = (vnode.elm =
         isDef(data) && isDef((i = (data as VNodeData).ns))
-          ? api.createElementNS(i, tag)
-          : api.createElement(tag));
-      if (hash < dot) elm.setAttribute("id", sel.slice(hash + 1, dot));
-      if (dotIdx > 0)
-        elm.setAttribute("class", sel.slice(dot + 1).replace(/\./g, " "));
-      for (i = 0, iLen = cbs.create.length; i < iLen; ++i)
-        cbs.create[i](emptyNode, vnode);
+          ? api.createElementNS(i, sel)
+          : api.createElement(sel));
+      for (i = 0, iLen = cbs.create.length; i < iLen; ++i) cbs.create[i](emptyNode, vnode);
       if (array(children)) {
         for (i = 0, iLen = children.length; i < iLen; ++i) {
           const ch = children[i];
@@ -237,8 +226,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       data = vnode.data;
     if (data !== undefined) {
       if (isDef((i = data.hook)) && isDef((i = i.destroy))) i(vnode);
-      for (i = 0, iLen = cbs.destroy.length; i < iLen; ++i)
-        cbs.destroy[i](vnode);
+      for (i = 0, iLen = cbs.destroy.length; i < iLen; ++i) cbs.destroy[i](vnode);
       if (vnode.children !== undefined) {
         for (j = 0, jLen = vnode.children.length; j < jLen; ++j) {
           i = vnode.children[j];
@@ -267,13 +255,8 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           invokeDestroyHook(ch);
           listeners = cbs.remove.length + 1;
           rm = createRmCb(ch.elm as Node, listeners);
-          for (i = 0, iLen = cbs.remove.length; i < iLen; ++i)
-            cbs.remove[i](ch, rm);
-          if (
-            isDef((i = ch.data)) &&
-            isDef((i = i.hook)) &&
-            isDef((i = i.remove))
-          ) {
+          for (i = 0, iLen = cbs.remove.length; i < iLen; ++i) cbs.remove[i](ch, rm);
+          if (isDef((i = ch.data)) && isDef((i = i.hook)) && isDef((i = i.remove))) {
             i(ch, rm);
           } else {
             rm();
@@ -335,11 +318,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       } else if (sameVnode(oldEndVnode, newStartVnode)) {
         // Vnode moved left
         patchVnode(oldEndVnode, newStartVnode, insertedVnodeQueue);
-        api.insertBefore(
-          parentElm,
-          oldEndVnode.elm as Node,
-          oldStartVnode.elm as Node
-        );
+        api.insertBefore(parentElm, oldEndVnode.elm as Node, oldStartVnode.elm as Node);
         oldEndVnode = oldCh[--oldEndIdx];
         newStartVnode = newCh[++newStartIdx];
       } else {
@@ -366,11 +345,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           } else {
             patchVnode(elmToMove, newStartVnode, insertedVnodeQueue);
             oldCh[idxInOld] = undefined as any;
-            api.insertBefore(
-              parentElm,
-              elmToMove.elm as Node,
-              oldStartVnode.elm as Node
-            );
+            api.insertBefore(parentElm, elmToMove.elm as Node, oldStartVnode.elm as Node);
           }
           newStartVnode = newCh[++newStartIdx];
         }
@@ -379,31 +354,16 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
     if (oldStartIdx <= oldEndIdx || newStartIdx <= newEndIdx) {
       if (oldStartIdx > oldEndIdx) {
         before = newCh[newEndIdx + 1] == null ? null : newCh[newEndIdx + 1].elm;
-        addVnodes(
-          parentElm,
-          before,
-          newCh,
-          newStartIdx,
-          newEndIdx,
-          insertedVnodeQueue
-        );
+        addVnodes(parentElm, before, newCh, newStartIdx, newEndIdx, insertedVnodeQueue);
       } else {
         removeVnodes(parentElm, oldCh, oldStartIdx, oldEndIdx);
       }
     }
   }
 
-  function patchVnode(
-    oldVnode: VNode,
-    vnode: VNode,
-    insertedVnodeQueue: VNodeQueue
-  ) {
+  function patchVnode(oldVnode: VNode, vnode: VNode, insertedVnodeQueue: VNodeQueue) {
     let i: any, iLen: number, hook: any;
-    if (
-      isDef((i = vnode.data)) &&
-      isDef((hook = i.hook)) &&
-      isDef((i = hook.prepatch))
-    ) {
+    if (isDef((i = vnode.data)) && isDef((hook = i.hook)) && isDef((i = hook.prepatch))) {
       i(oldVnode, vnode);
     }
     const elm = (vnode.elm = oldVnode.elm as Node);
@@ -411,20 +371,14 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
     let ch = vnode.children;
     if (oldVnode === vnode) return;
     if (vnode.data !== undefined) {
-      for (i = 0, iLen = cbs.update.length; i < iLen; ++i)
-        cbs.update[i](oldVnode, vnode);
+      for (i = 0, iLen = cbs.update.length; i < iLen; ++i) cbs.update[i](oldVnode, vnode);
       i = vnode.data.hook;
       if (isDef(i) && isDef((i = i.update))) i(oldVnode, vnode);
     }
     if (isUndef(vnode.text)) {
       if (isDef(oldCh) && isDef(ch)) {
         if (oldCh !== ch)
-          updateChildren(
-            elm,
-            oldCh as Array<VNode>,
-            ch as Array<VNode>,
-            insertedVnodeQueue
-          );
+          updateChildren(elm, oldCh as Array<VNode>, ch as Array<VNode>, insertedVnodeQueue);
       } else if (isDef(ch)) {
         if (isDef(oldVnode.text)) api.setTextContent(elm, "");
         addVnodes(
@@ -436,23 +390,13 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           insertedVnodeQueue
         );
       } else if (isDef(oldCh)) {
-        removeVnodes(
-          elm,
-          oldCh as Array<VNode>,
-          0,
-          (oldCh as Array<VNode>).length - 1
-        );
+        removeVnodes(elm, oldCh as Array<VNode>, 0, (oldCh as Array<VNode>).length - 1);
       } else if (isDef(oldVnode.text)) {
         api.setTextContent(elm, "");
       }
     } else if (oldVnode.text !== vnode.text) {
       if (isDef(oldCh)) {
-        removeVnodes(
-          elm,
-          oldCh as Array<VNode>,
-          0,
-          (oldCh as Array<VNode>).length - 1
-        );
+        removeVnodes(elm, oldCh as Array<VNode>, 0, (oldCh as Array<VNode>).length - 1);
       }
       api.setTextContent(elm, vnode.text as string);
     }
@@ -510,21 +454,13 @@ interface DOMAPI {
   createElementNS: (namespaceURI: string, qualifiedName: string) => Element;
   createTextNode: (text: string) => Text;
   createComment: (text: string) => Comment;
-  insertBefore: (
-    parentNode: Node,
-    newNode: Node,
-    referenceNode: Node | null
-  ) => void;
+  insertBefore: (parentNode: Node, newNode: Node, referenceNode: Node | null) => void;
   removeChild: (node: Node, child: Node) => void;
   appendChild: (node: Node, child: Node) => void;
   parentNode: (node: Node) => Node;
   nextSibling: (node: Node) => Node;
   tagName: (elm: Element) => string;
   setTextContent: (node: Node, text: string | null) => void;
-  getTextContent: (node: Node) => string | null;
-  isElement: (node: Node) => node is Element;
-  isText: (node: Node) => node is Text;
-  isComment: (node: Node) => node is Comment;
 }
 
 function createElement(tagName: any): HTMLElement {
@@ -543,11 +479,7 @@ function createComment(text: string): Comment {
   return document.createComment(text);
 }
 
-function insertBefore(
-  parentNode: Node,
-  newNode: Node,
-  referenceNode: Node | null
-): void {
+function insertBefore(parentNode: Node, newNode: Node, referenceNode: Node | null): void {
   parentNode.insertBefore(newNode, referenceNode);
 }
 
@@ -575,22 +507,6 @@ function setTextContent(node: Node, text: string | null): void {
   node.textContent = text;
 }
 
-function getTextContent(node: Node): string | null {
-  return node.textContent;
-}
-
-function isElement(node: Node): node is Element {
-  return node.nodeType === 1;
-}
-
-function isText(node: Node): node is Text {
-  return node.nodeType === 3;
-}
-
-function isComment(node: Node): node is Comment {
-  return node.nodeType === 8;
-}
-
 const htmlDomApi = {
   createElement,
   createElementNS,
@@ -602,11 +518,7 @@ const htmlDomApi = {
   parentNode,
   nextSibling,
   tagName,
-  setTextContent,
-  getTextContent,
-  isElement,
-  isText,
-  isComment
+  setTextContent
 } as DOMAPI;
 
 //------------------------------------------------------------------------------
@@ -644,21 +556,19 @@ type VNodeChildElement = VNode | string | number | undefined | null;
 type ArrayOrElement<T> = T | T[];
 type VNodeChildren = ArrayOrElement<VNodeChildElement>;
 
-function addNS(
-  data: any,
-  children: VNodes | undefined,
-  sel: string | undefined
-): void {
+export function addNS(data: any, children: VNodes | undefined, sel: string | undefined): void {
+  if (sel === "dummy") {
+    // we do not need to add the namespace on dummy elements, they come from a
+    // subcomponent, which will handle the namespace itself
+    return;
+  }
   data.ns = "http://www.w3.org/2000/svg";
   if (sel !== "foreignObject" && children !== undefined) {
     for (let i = 0, iLen = children.length; i < iLen; ++i) {
-      let childData = children[i].data;
+      const child = children[i];
+      let childData = child.data;
       if (childData !== undefined) {
-        addNS(
-          childData,
-          (children[i] as VNode).children as VNodes,
-          children[i].sel
-        );
+        addNS(childData, (child as VNode).children as VNodes, child.sel);
       }
     }
   }
@@ -697,245 +607,8 @@ export function h(sel: any, b?: any, c?: any): VNode {
   if (children !== undefined) {
     for (i = 0, iLen = children.length; i < iLen; ++i) {
       if (primitive(children[i]))
-        children[i] = vnode(
-          undefined,
-          undefined,
-          undefined,
-          children[i],
-          undefined
-        );
+        children[i] = vnode(undefined, undefined, undefined, children[i], undefined);
     }
   }
-  if (
-    sel[0] === "s" &&
-    sel[1] === "v" &&
-    sel[2] === "g" &&
-    (sel.length === 3 || sel[3] === "." || sel[3] === "#")
-  ) {
-    addNS(data, children, sel);
-  }
   return vnode(sel, data, children, text, undefined);
 }
-
-//------------------------------------------------------------------------------
-// module/props.ts
-//------------------------------------------------------------------------------
-type Props = Record<string, any>;
-
-function updateProps(oldVnode: VNode, vnode: VNode): void {
-  var key: string,
-    cur: any,
-    old: any,
-    elm = vnode.elm,
-    oldProps = (oldVnode.data as VNodeData).props,
-    props = (vnode.data as VNodeData).props;
-
-  if (!oldProps && !props) return;
-  if (oldProps === props) return;
-  oldProps = oldProps || {};
-  props = props || {};
-
-  for (key in oldProps) {
-    if (!props[key]) {
-      delete (elm as any)[key];
-    }
-  }
-  for (key in props) {
-    cur = props[key];
-    old = oldProps[key];
-    if (old !== cur && (key !== "value" || (elm as any)[key] !== cur)) {
-      (elm as any)[key] = cur;
-    }
-  }
-}
-
-export const propsModule = {
-  create: updateProps,
-  update: updateProps
-} as Module;
-
-//------------------------------------------------------------------------------
-// module/module.ts
-//------------------------------------------------------------------------------
-interface Module {
-  pre: PreHook;
-  create: CreateHook;
-  update: UpdateHook;
-  destroy: DestroyHook;
-  remove: RemoveHook;
-  post: PostHook;
-}
-
-//------------------------------------------------------------------------------
-// module/eventlisteners.ts
-//------------------------------------------------------------------------------
-type On = {
-  [N in keyof HTMLElementEventMap]?: (ev: HTMLElementEventMap[N]) => void
-} & {
-  [event: string]: EventListener;
-};
-
-function invokeHandler(handler: any, vnode?: VNode, event?: Event): void {
-  if (typeof handler === "function") {
-    // call function handler
-    handler.call(vnode, event, vnode);
-  } else if (typeof handler === "object") {
-    // call handler with arguments
-    if (typeof handler[0] === "function") {
-      // special case for single argument for performance
-      if (handler.length === 2) {
-        handler[0].call(vnode, handler[1], event, vnode);
-      } else {
-        var args = handler.slice(1);
-        args.push(event);
-        args.push(vnode);
-        handler[0].apply(vnode, args);
-      }
-    } else {
-      // call multiple handlers
-      for (let i = 0, iLen = handler.length; i < iLen; i++) {
-        invokeHandler(handler[i], vnode, event);
-      }
-    }
-  }
-}
-
-function handleEvent(event: Event, vnode: VNode) {
-  var name = event.type,
-    on = (vnode.data as VNodeData).on;
-
-  // call event handler(s) if exists
-  if (on && on[name]) {
-    invokeHandler(on[name], vnode, event);
-  }
-}
-
-function createListener() {
-  return function handler(event: Event) {
-    handleEvent(event, (handler as any).vnode);
-  };
-}
-
-function updateEventListeners(oldVnode: VNode, vnode?: VNode): void {
-  var oldOn = (oldVnode.data as VNodeData).on,
-    oldListener = (oldVnode as any).listener,
-    oldElm: Element = oldVnode.elm as Element,
-    on = vnode && (vnode.data as VNodeData).on,
-    elm: Element = (vnode && vnode.elm) as Element,
-    name: string;
-
-  // optimization for reused immutable handlers
-  if (oldOn === on) {
-    return;
-  }
-
-  // remove existing listeners which no longer used
-  if (oldOn && oldListener) {
-    // if element changed or deleted we remove all existing listeners unconditionally
-    if (!on) {
-      for (name in oldOn) {
-        // remove listener if element was changed or existing listeners removed
-        oldElm.removeEventListener(name, oldListener, false);
-      }
-    } else {
-      for (name in oldOn) {
-        // remove listener if existing listener removed
-        if (!on[name]) {
-          oldElm.removeEventListener(name, oldListener, false);
-        }
-      }
-    }
-  }
-
-  // add new listeners which has not already attached
-  if (on) {
-    // reuse existing listener or create new
-    var listener = ((vnode as any).listener =
-      (oldVnode as any).listener || createListener());
-    // update vnode for listener
-    listener.vnode = vnode;
-
-    // if element changed or added we add all needed listeners unconditionally
-    if (!oldOn) {
-      for (name in on) {
-        // add listener if element was changed or new listeners added
-        elm.addEventListener(name, listener, false);
-      }
-    } else {
-      for (name in on) {
-        // add listener if new listener added
-        if (!oldOn[name]) {
-          elm.addEventListener(name, listener, false);
-        }
-      }
-    }
-  }
-}
-
-export const eventListenersModule = {
-  create: updateEventListeners,
-  update: updateEventListeners,
-  destroy: updateEventListeners
-} as Module;
-
-//------------------------------------------------------------------------------
-// attributes.ts
-//------------------------------------------------------------------------------
-type Attrs = Record<string, string | number | boolean>;
-
-const xlinkNS = "http://www.w3.org/1999/xlink";
-const xmlNS = "http://www.w3.org/XML/1998/namespace";
-const colonChar = 58;
-const xChar = 120;
-
-function updateAttrs(oldVnode: VNode, vnode: VNode): void {
-  var key: string,
-    elm: Element = vnode.elm as Element,
-    oldAttrs = (oldVnode.data as VNodeData).attrs,
-    attrs = (vnode.data as VNodeData).attrs;
-
-  if (!oldAttrs && !attrs) return;
-  if (oldAttrs === attrs) return;
-  oldAttrs = oldAttrs || {};
-  attrs = attrs || {};
-
-  // update modified attributes, add new attributes
-  for (key in attrs) {
-    const cur = attrs[key];
-    const old = oldAttrs[key];
-    if (old !== cur) {
-      if (cur === true) {
-        elm.setAttribute(key, "");
-      } else if (cur === false) {
-        elm.removeAttribute(key);
-      } else {
-        if (key.charCodeAt(0) !== xChar) {
-          elm.setAttribute(key, cur);
-        } else if (key.charCodeAt(3) === colonChar) {
-          // Assume xml namespace
-          elm.setAttributeNS(xmlNS, key, cur);
-        } else if (key.charCodeAt(5) === colonChar) {
-          // Assume xlink namespace
-          elm.setAttributeNS(xlinkNS, key, cur);
-        } else {
-          elm.setAttribute(key, cur);
-        }
-      }
-    }
-  }
-  // remove removed attributes
-  // use `in` operator since the previous `for` iteration uses it (.i.e. add even attributes with undefined value)
-  // the other option is to remove all attributes with value == undefined
-  for (key in oldAttrs) {
-    if (!(key in attrs)) {
-      elm.removeAttribute(key);
-    }
-  }
-}
-
-export const attrsModule = {
-  create: updateAttrs,
-  update: updateAttrs
-} as Module;
-
-export const patch = init([eventListenersModule, attrsModule, propsModule]);

tests/__snapshots__/animations.test.ts.snap

@@ -1,88 +1,90 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`animations t-transition combined with t-widget 1`] = `
+exports[`animations t-transition combined with component 1`] = `
 "function anonymous(context,extra
 ) {
-    let utils = this.utils;
+    let utils = this.constructor.utils;
     let QWeb = this.constructor;
+    let parent = context;
     let owner = context;
-    var h = this.utils.h;
+    let sibling = null;
+    var h = this.h;
     let c1 = [], p1 = {key:1};
     var vn1 = h('div', p1, c1);
-    //WIDGET
-    let def3;
-    let w4 = 4 in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[4]] : false;
-    let _2_index = c1.length;
-    c1.push(null);
-    let props4 = {};
-    if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
-        if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
-            def3 = w4.__owl__.renderPromise;
-        } else {
-            w4.destroy();
-            w4 = false;
-        }
+    //COMPONENT
+    let templateId3 = \`__4__\`;
+    let w3 = templateId3 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[templateId3]] : false;
+    let props3 = {};
+    if (w3 && w3.__owl__.currentFiber && !w3.__owl__.vnode) {
+        w3.destroy();
+        w3 = false;
     }
-    if (!w4) {
-        let widgetKey4 = \`Child\`;
-        let W4 = context.widgets && context.widgets[widgetKey4] || QWeb.widgets[widgetKey4];
-        if (!W4) {throw new Error('Cannot find the definition of widget \\"' + widgetKey4 + '\\"')}
-        w4 = new W4(owner, props4);
-        context.__owl__.cmap[4] = w4.__owl__.id;
-        def3 = w4._prepare();
-        def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4, hook: {insert(vn) {let nvn=w4._mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
-          w4.destroy();
-        };
-        utils.transitionRemove(vn, 'chimay', finalize);}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
+    if (w3) {
+        w3.__updateProps(props3, extra.fiber, undefined, undefined, sibling);
+        let pvnode = w3.__owl__.pvnode;
+        c1.push(pvnode);
     } else {
-        def3 = def3 || w4._updateProps(props4, extra.forceUpdate, extra.patchQueue);
-        def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
+        let componentKey3 = \`Child\`;
+        let W3 = context.constructor.components[componentKey3] || QWeb.components[componentKey3]|| context['Child'];
+        if (!W3) {throw new Error('Cannot find the definition of component \\"' + componentKey3 + '\\"')}
+        w3 = new W3(parent, props3);
+        parent.__owl__.cmap[templateId3] = w3.__owl__.id;
+        let def2 = w3.__prepare(extra.fiber, undefined, undefined, sibling);
+        let pvnode = h('dummy', {key: templateId3, hook: {insert(vn) { let nvn=w3.__mount(fiber, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
+          w3.destroy();
+        };
+        utils.transitionRemove(vn, 'chimay', finalize);}}});
+        const fiber = w3.__owl__.currentFiber;
+        def2.then(function () {if (w3.__owl__.isDestroyed) {return;} const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
+        c1.push(pvnode);
+        w3.__owl__.pvnode = pvnode;
     }
-    extra.promises.push(def3);
+    sibling = w3.__owl__.currentFiber || sibling;
     return vn1;
 }"
 `;
 
-exports[`animations t-transition combined with t-widget and t-if 1`] = `
+exports[`animations t-transition combined with t-component and t-if 1`] = `
 "function anonymous(context,extra
 ) {
-    let utils = this.utils;
+    let utils = this.constructor.utils;
     let QWeb = this.constructor;
+    let parent = context;
     let owner = context;
-    var h = this.utils.h;
+    let sibling = null;
+    var h = this.h;
     let c1 = [], p1 = {key:1};
     var vn1 = h('div', p1, c1);
     if (context['state'].display) {
-        //WIDGET
-        let def3;
-        let w4 = 4 in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[4]] : false;
-        let _2_index = c1.length;
-        c1.push(null);
-        let props4 = {};
-        if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
-            if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
-                def3 = w4.__owl__.renderPromise;
-            } else {
-                w4.destroy();
-                w4 = false;
-            }
+        //COMPONENT
+        let templateId3 = \`__4__\`;
+        let w3 = templateId3 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[templateId3]] : false;
+        let props3 = {};
+        if (w3 && w3.__owl__.currentFiber && !w3.__owl__.vnode) {
+            w3.destroy();
+            w3 = false;
         }
-        if (!w4) {
-            let widgetKey4 = \`Child\`;
-            let W4 = context.widgets && context.widgets[widgetKey4] || QWeb.widgets[widgetKey4];
-            if (!W4) {throw new Error('Cannot find the definition of widget \\"' + widgetKey4 + '\\"')}
-            w4 = new W4(owner, props4);
-            context.__owl__.cmap[4] = w4.__owl__.id;
-            def3 = w4._prepare();
-            def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4, hook: {insert(vn) {let nvn=w4._mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
-          w4.destroy();
-        };
-        utils.transitionRemove(vn, 'chimay', finalize);}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
+        if (w3) {
+            w3.__updateProps(props3, extra.fiber, undefined, undefined, sibling);
+            let pvnode = w3.__owl__.pvnode;
+            c1.push(pvnode);
         } else {
-            def3 = def3 || w4._updateProps(props4, extra.forceUpdate, extra.patchQueue);
-            def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
+            let componentKey3 = \`Child\`;
+            let W3 = context.constructor.components[componentKey3] || QWeb.components[componentKey3]|| context['Child'];
+            if (!W3) {throw new Error('Cannot find the definition of component \\"' + componentKey3 + '\\"')}
+            w3 = new W3(parent, props3);
+            parent.__owl__.cmap[templateId3] = w3.__owl__.id;
+            let def2 = w3.__prepare(extra.fiber, undefined, undefined, sibling);
+            let pvnode = h('dummy', {key: templateId3, hook: {insert(vn) { let nvn=w3.__mount(fiber, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
+          w3.destroy();
+        };
+        utils.transitionRemove(vn, 'chimay', finalize);}}});
+            const fiber = w3.__owl__.currentFiber;
+            def2.then(function () {if (w3.__owl__.isDestroyed) {return;} const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
+            c1.push(pvnode);
+            w3.__owl__.pvnode = pvnode;
         }
-        extra.promises.push(def3);
+        sibling = w3.__owl__.currentFiber || sibling;
     }
     return vn1;
 }"
@@ -91,15 +93,17 @@ exports[`animations t-transition combined with t-widget and t-if 1`] = `
 exports[`animations t-transition with no delay/duration 1`] = `
 "function anonymous(context,extra
 ) {
-    var h = this.utils.h;
+    let utils = this.constructor.utils;
+    let sibling = null;
+    var h = this.h;
     let c1 = [], p1 = {key:1};
     var vn1 = h('span', p1, c1);
     p1.hook = {
       insert: vn => {
-        this.utils.transitionInsert(vn, 'jupiler');
+        utils.transitionInsert(vn, 'jupiler');
       },
       remove: (vn, rm) => {
-        this.utils.transitionRemove(vn, 'jupiler', rm);
+        utils.transitionRemove(vn, 'jupiler', rm);
       },
     };
     c1.push({text: \`blue\`});
@@ -110,15 +114,17 @@ exports[`animations t-transition with no delay/duration 1`] = `
 exports[`animations t-transition, on a simple node (insert) 1`] = `
 "function anonymous(context,extra
 ) {
-    var h = this.utils.h;
+    let utils = this.constructor.utils;
+    let sibling = null;
+    var h = this.h;
     let c1 = [], p1 = {key:1};
     var vn1 = h('span', p1, c1);
     p1.hook = {
       insert: vn => {
-        this.utils.transitionInsert(vn, 'chimay');
+        utils.transitionInsert(vn, 'chimay');
       },
       remove: (vn, rm) => {
-        this.utils.transitionRemove(vn, 'chimay', rm);
+        utils.transitionRemove(vn, 'chimay', rm);
       },
     };
     c1.push({text: \`blue\`});

tests/__snapshots__/store.test.ts.snap

@@ -1,17 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`connecting a component to store connecting a component to a local store 1`] = `"<div></div>"`;
-
-exports[`connecting a component to store connecting a component to a local store 2`] = `"<div><span>hello</span></div>"`;
-
-exports[`connecting a component to store connecting a component works 1`] = `"<div></div>"`;
-
-exports[`connecting a component to store connecting a component works 2`] = `"<div><span>hello</span></div>"`;
-
-exports[`connecting a component to store deep and shallow connecting a component 1`] = `"<div><span>Kasteel</span></div>"`;
-
-exports[`connecting a component to store deep and shallow connecting a component 2`] = `"<div><span>Kasteel</span></div>"`;
-
-exports[`connecting a component to store deep and shallow connecting a component 3`] = `"<div><span>Bertinchamps</span></div>"`;
-
-exports[`connecting a component to store deep and shallow connecting a component 4`] = `"<div><span>Kasteel</span></div>"`;

tests/__snapshots__/store_hooks.test.ts.snap

@@ -0,0 +1,5 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`various scenarios scenarios with async store updates and some components events 1`] = `"<div><button>Do stuff</button><div><span>Attachment 100</span><span>Name: text.txt</span></div></div>"`;
+
+exports[`various scenarios scenarios with async store updates and some components events 2`] = `"<div><button>Do stuff</button></div>"`;

tests/__snapshots__/untitled.js

@@ -1,33 +0,0 @@
-function anonymous(context, extra) {
- var h = this.utils.h;
-          let c1 = [], p1 = {key:1};
-          var vn1 = h('div', p1, c1);
-          if (context['state'].display) {
-              //WIDGET
-              let _2_index = c1.length;
-              c1.push(null);
-              let def3;
-              let w4 = 4 in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[4]] : false;
-              let props4 = {};
-              if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode && props4 !== w4.__owl__.renderProps) {
-                  w4.destroy();
-                  w4 = false
-              }
-              if (!w4) {
-                  let W4 = context.widgets['Child'];
-                  if (!W4) {throw new Error(`Cannot find the definition of widget "Child"`)}
-                  w4 = new W4(owner, props4);
-                  context.__owl__.cmap[4] = w4.__owl__.id;
-                  def3 = w4._prepare();
-                  def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4, hook: {insert: (vn) => {let nvn=w4._mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;this.utils.transitionInsert(vn.elm, 'chimay');},remove: () => {},destroy: (vn) => {let finalize = () => {
-                w4.destroy();
-              };
-              this.utils.transitionRemove(vn.elm, 'chimay', finalize);}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
-              } else {
-                  def3 = w4._updateProps(props4, extra.forceUpdate, extra.patchQueue);
-                  def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
-              }
-              extra.promises.push(def3);
-          }
-
-}

tests/animations.test.ts

@@ -1,10 +1,10 @@
-import { Component, Env } from "../src/component";
-import { QWeb } from "../src/qweb_core";
+import { Component, Env } from "../src/component/component";
+import { QWeb } from "../src/qweb/index";
+import { useState, useRef } from "../src/hooks";
 import {
   makeDeferred,
   makeTestFixture,
   makeTestEnv,
-  nextTick,
   patchNextFrame,
   renderToDOM,
   unpatchNextFrame
@@ -18,7 +18,7 @@ import {
 // - fixture: a div, appended to the DOM, intended to be the target of dom
 //   manipulations.  Note that it is removed after each test.
 // - qweb: a new QWeb instance
-// - env: a WEnv, necessary to create new widgets
+// - env: a WEnv, necessary to create new components
 // - cssEl: a stylesheet injected into the dom
 
 let fixture: HTMLElement;
@@ -36,7 +36,7 @@ afterEach(() => {
   fixture.remove();
 });
 
-class Widget extends Component<any, any, any> {}
+class Widget extends Component<any, any> {}
 
 //------------------------------------------------------------------------------
 // Tests
@@ -106,7 +106,7 @@ describe("animations", () => {
       `<div><span t-if="!state.hide" t-transition="chimay">blue</span></div>`
     );
     class TestWidget extends Widget {
-      state = { hide: false };
+      state = useState({ hide: false });
     }
     const widget = new TestWidget(env);
 
@@ -148,7 +148,8 @@ describe("animations", () => {
       `<div><span t-ref="span" t-transition="chimay">blue</span></div>`
     );
     class TestWidget extends Widget {
-      state = { hide: false };
+      state = useState({ hide: false });
+      span = useRef("span");
     }
     const widget = new TestWidget(env);
 
@@ -163,25 +164,22 @@ describe("animations", () => {
     });
     await widget.mount(fixture);
     spanNode = widget.el!.children[0];
-    expect(widget.refs.span).toBe(spanNode);
+    expect(widget.span.el).toBe(spanNode);
     expect(spanNode.className).toBe("chimay-enter chimay-enter-active");
     await def; // wait for the mocked repaint to be done
     spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
     expect(spanNode.className).toBe("");
   });
 
-  test("t-transition combined with t-widget", async () => {
+  test("t-transition combined with component", async () => {
     expect.assertions(5);
 
-    env.qweb.addTemplate(
-      "Parent",
-      `<div><t t-widget="Child" t-transition="chimay"/></div>`
-    );
+    env.qweb.addTemplate("Parent", `<div><Child t-transition="chimay"/></div>`);
     env.qweb.addTemplate("Child", `<span>blue</span>`);
-    class Parent extends Widget {
-      widgets = { Child: Child };
-    }
     class Child extends Widget {}
+    class Parent extends Widget {
+      static components = { Child: Child };
+    }
     const widget = new Parent(env);
 
     let def = makeDeferred();
@@ -209,19 +207,19 @@ describe("animations", () => {
     expect(fixture.innerHTML).toBe('<div><span class="">blue</span></div>');
   });
 
-  test("t-transition combined with t-widget and t-if", async () => {
+  test("t-transition combined with t-component and t-if", async () => {
     expect.assertions(8);
 
     env.qweb.addTemplate(
       "Parent",
-      `<div><t t-if="state.display" t-widget="Child" t-transition="chimay"/></div>`
+      `<div><t t-if="state.display" t-component="Child" t-transition="chimay"/></div>`
     );
     env.qweb.addTemplate("Child", `<span>blue</span>`);
-    class Parent extends Widget {
-      widgets = { Child: Child };
-      state = { display: true };
-    }
     class Child extends Widget {}
+    class Parent extends Widget {
+      static components = { Child: Child };
+      state = useState({ display: true });
+    }
     const widget = new Parent(env);
 
     let def = makeDeferred();
@@ -253,11 +251,11 @@ describe("animations", () => {
     widget.state.display = false;
     patchNextFrame(cb => {
       expect(fixture.innerHTML).toBe(
-        '<div><span class="chimay-leave chimay-leave-active" data-owl-key="4">blue</span></div>'
+        '<div><span class="chimay-leave chimay-leave-active" data-owl-key="__4__">blue</span></div>'
       );
       cb();
       expect(fixture.innerHTML).toBe(
-        '<div><span class="chimay-leave-active chimay-leave-to" data-owl-key="4">blue</span></div>'
+        '<div><span class="chimay-leave-active chimay-leave-to" data-owl-key="__4__">blue</span></div>'
       );
       def.resolve();
     });
@@ -266,28 +264,6 @@ describe("animations", () => {
     expect(fixture.innerHTML).toBe("<div></div>");
   });
 
-  test("t-transition combined with t-mounted", async () => {
-    env.qweb.addTemplate(
-      "TestWidget",
-      `<div><span t-if="state.flag" t-mounted="f" t-transition="chimay">blue</span></div>`
-    );
-    class TestWidget extends Widget {
-      state = { flag: false };
-      f() {}
-    }
-    const widget = new TestWidget(env);
-    widget.f = jest.fn();
-    await widget.mount(fixture);
-
-    patchNextFrame(cb => cb());
-    expect(widget.f).toHaveBeenCalledTimes(0);
-
-    widget.state.flag = true;
-    await nextTick();
-    expect(widget.f).toHaveBeenCalledTimes(1);
-    unpatchNextFrame();
-  });
-
   test("t-transition, remove and re-add before transitionend", async () => {
     expect.assertions(11);
 
@@ -300,10 +276,8 @@ describe("animations", () => {
       </templates>`
     );
     class Parent extends Widget {
-      constructor(parent) {
-        super(parent);
-        this.state = { flag: false };
-      }
+      state = useState({ flag: false });
+
       toggle() {
         this.state.flag = !this.state.flag;
       }
@@ -320,9 +294,7 @@ describe("animations", () => {
       expect(spans.length).toBe(1);
       expect(spans[0].className).toBe(`chimay-${phase} chimay-${phase}-active`);
       cb();
-      expect(spans[0].className).toBe(
-        `chimay-${phase}-active chimay-${phase}-to`
-      );
+      expect(spans[0].className).toBe(`chimay-${phase}-active chimay-${phase}-to`);
       def.resolve();
     });
 
@@ -330,9 +302,7 @@ describe("animations", () => {
     button!.click();
     await def; // wait for the mocked repaint to be done
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
-    expect(fixture.innerHTML).toBe(
-      '<div><button>Toggle</button><span class="">blue</span></div>'
-    );
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
 
     // click to remove the span, and click again to re-add it before transitionend
     def = makeDeferred();
@@ -346,30 +316,26 @@ describe("animations", () => {
 
     await def; // wait for the mocked repaint to be done
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
-    expect(fixture.innerHTML).toBe(
-      '<div><button>Toggle</button><span class="">blue</span></div>'
-    );
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
   });
 
-  test("t-transition combined with t-widget, remove and re-add before transitionend", async () => {
+  test("t-transition combined with t-component, remove and re-add before transitionend", async () => {
     expect.assertions(11);
 
     env.qweb.addTemplates(
       `<templates>
         <div t-name="Parent">
           <button t-on-click="toggle">Toggle</button>
-          <t t-if="state.flag" t-widget="Child" t-transition="chimay"/>
+          <t t-if="state.flag" t-component="Child" t-transition="chimay"/>
         </div>
         <span t-name="Child">blue</span>
       </templates>`
     );
     class Child extends Widget {}
     class Parent extends Widget {
-      widgets = { Child };
-      constructor(parent) {
-        super(parent);
-        this.state = { flag: false };
-      }
+      static components = { Child };
+      state = useState({ flag: false });
+
       toggle() {
         this.state.flag = !this.state.flag;
       }
@@ -386,9 +352,7 @@ describe("animations", () => {
       expect(spans.length).toBe(1);
       expect(spans[0].className).toBe(`chimay-${phase} chimay-${phase}-active`);
       cb();
-      expect(spans[0].className).toBe(
-        `chimay-${phase}-active chimay-${phase}-to`
-      );
+      expect(spans[0].className).toBe(`chimay-${phase}-active chimay-${phase}-to`);
       def.resolve();
     });
 
@@ -396,9 +360,7 @@ describe("animations", () => {
     button!.click();
     await def; // wait for the mocked repaint to be done
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
-    expect(fixture.innerHTML).toBe(
-      '<div><button>Toggle</button><span class="">blue</span></div>'
-    );
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
 
     // click to remove the span, and click again to re-add it before transitionend
     def = makeDeferred();
@@ -412,8 +374,6 @@ describe("animations", () => {
 
     await def; // wait for the mocked repaint to be done
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
-    expect(fixture.innerHTML).toBe(
-      '<div><button>Toggle</button><span class="">blue</span></div>'
-    );
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
   });
 });

tests/component/__snapshots__/props_validation.test.ts.snap

@@ -0,0 +1,43 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`props validation props are validated in dev mode (code snapshot) 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.constructor.utils;
+    let QWeb = this.constructor;
+    let parent = context;
+    let owner = context;
+    let sibling = null;
+    var h = this.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('div', p1, c1);
+    //COMPONENT
+    let templateId3 = \`__4__\`;
+    let w3 = templateId3 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[templateId3]] : false;
+    let props3 = {message:1};
+    if (w3 && w3.__owl__.currentFiber && !w3.__owl__.vnode) {
+        w3.destroy();
+        w3 = false;
+    }
+    if (w3) {
+        utils.validateProps(w3.constructor, props3)
+        w3.__updateProps(props3, extra.fiber, undefined, undefined, sibling);
+        let pvnode = w3.__owl__.pvnode;
+        c1.push(pvnode);
+    } else {
+        let componentKey3 = \`Child\`;
+        let W3 = context.constructor.components[componentKey3] || QWeb.components[componentKey3]|| context['Child'];
+        if (!W3) {throw new Error('Cannot find the definition of component \\"' + componentKey3 + '\\"')}
+        w3 = new W3(parent, props3);
+        parent.__owl__.cmap[templateId3] = w3.__owl__.id;
+        let def2 = w3.__prepare(extra.fiber, undefined, undefined, sibling);
+        let pvnode = h('dummy', {key: templateId3, hook: {insert(vn) { let nvn=w3.__mount(fiber, pvnode.elm);pvnode.elm=nvn.elm;},remove() {},destroy(vn) {w3.destroy();}}});
+        const fiber = w3.__owl__.currentFiber;
+        def2.then(function () {if (w3.__owl__.isDestroyed) {return;} const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
+        c1.push(pvnode);
+        w3.__owl__.pvnode = pvnode;
+    }
+    sibling = w3.__owl__.currentFiber || sibling;
+    return vn1;
+}"
+`;

tests/component/props_validation.test.ts

@@ -1,6 +1,8 @@
-import { Component, Env } from "../src/component";
-import { makeTestFixture, makeTestEnv } from "./helpers";
-import { QWeb } from "../src";
+import { Component, Env } from "../../src/component/component";
+import { makeTestFixture, makeTestEnv, nextTick } from "../helpers";
+import { useState } from "../../src/hooks";
+import { QWeb } from "../../src/qweb";
+import { xml } from "../../src/tags";
 
 //------------------------------------------------------------------------------
 // Setup and helpers
@@ -22,7 +24,7 @@ afterEach(() => {
   QWeb.dev = dev;
 });
 
-class Widget extends Component<any, any, any> {}
+class Widget extends Component<any, any> {}
 
 //------------------------------------------------------------------------------
 // Tests
@@ -31,6 +33,7 @@ describe("props validation", () => {
   test("validation is only done in dev mode", async () => {
     class TestWidget extends Widget {
       static props = ["message"];
+      static template = xml`<div>hey</div>`;
     }
 
     QWeb.dev = true;
@@ -45,27 +48,15 @@ describe("props validation", () => {
     }).not.toThrow();
   });
 
-  test("props validation is also done on update props", async () => {
-    expect.assertions(1);
-    class TestWidget extends Widget {
-      static props = ["message"];
-    }
-    const w = new TestWidget(env, { message: "bottle" });
-    try {
-      await w._updateProps({});
-    } catch (e) {
-      expect(e.message).toBe("Missing props 'message' (widget 'TestWidget')");
-    }
-  });
-
   test("props: list of strings", async () => {
     class TestWidget extends Widget {
       static props = ["message"];
+      static template = xml`<div>hey</div>`;
     }
 
     expect(() => {
       new TestWidget(env);
-    }).toThrow("Missing props 'message' (widget 'TestWidget')");
+    }).toThrow("Missing props 'message' (component 'TestWidget')");
   });
 
   test("validate simple types", async () => {
@@ -80,6 +71,7 @@ describe("props validation", () => {
 
     for (let test of Tests) {
       let TestWidget = class extends Widget {
+        static template = xml`<div>hey</div>`;
         static props = { p: test.type };
       };
 
@@ -93,7 +85,7 @@ describe("props validation", () => {
 
       expect(() => {
         new TestWidget(env, { p: test.ko });
-      }).toThrow("Props 'p' of invalid type in widget");
+      }).toThrow("Props 'p' of invalid type in component");
     }
   });
 
@@ -109,6 +101,7 @@ describe("props validation", () => {
 
     for (let test of Tests) {
       let TestWidget = class extends Widget {
+        static template = xml`<div>hey</div>`;
         static props = { p: { type: test.type } };
       };
 
@@ -122,13 +115,13 @@ describe("props validation", () => {
 
       expect(() => {
         new TestWidget(env, { p: test.ko });
-      }).toThrow("Props 'p' of invalid type in widget");
+      }).toThrow("Props 'p' of invalid type in component");
     }
   });
 
-
   test("can validate a prop with multiple types", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = { p: [String, Boolean] };
     };
 
@@ -139,28 +132,28 @@ describe("props validation", () => {
 
     expect(() => {
       new TestWidget(env, { p: 1 });
-    }).toThrow("Props 'p' of invalid type in widget");
+    }).toThrow("Props 'p' of invalid type in component");
   });
 
   test("can validate an optional props", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = { p: { type: String, optional: true } };
     };
 
     expect(() => {
       new TestWidget(env, { p: "hey" });
-      new TestWidget(env, { });
+      new TestWidget(env, {});
     }).not.toThrow();
 
     expect(() => {
       new TestWidget(env, { p: 1 });
     }).toThrow();
-
   });
 
-
   test("can validate an array with given primitive type", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = { p: { type: Array, element: String } };
     };
 
@@ -180,6 +173,7 @@ describe("props validation", () => {
 
   test("can validate an array with multiple sub element types", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = { p: { type: Array, element: [String, Boolean] } };
     };
 
@@ -196,6 +190,7 @@ describe("props validation", () => {
 
   test("can validate an object with simple shape", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = {
         p: { type: Object, shape: { id: Number, url: String } }
       };
@@ -217,12 +212,13 @@ describe("props validation", () => {
 
   test("can validate recursively complicated prop def", async () => {
     let TestWidget = class extends Widget {
+      static template = xml`<div>hey</div>`;
       static props = {
         p: {
           type: Object,
           shape: {
             id: Number,
-            url: [Boolean, {type: Array, element: Number}],
+            url: [Boolean, { type: Array, element: Number }]
           }
         }
       };
@@ -230,21 +226,109 @@ describe("props validation", () => {
 
     expect(() => {
       new TestWidget(env, { p: { id: 1, url: true } });
-      new TestWidget(env, { p: { id: 1, url: [12]} });
+      new TestWidget(env, { p: { id: 1, url: [12] } });
     }).not.toThrow();
 
     expect(() => {
-      new TestWidget(env, { p: { id: 1, url: [12, true]} });
+      new TestWidget(env, { p: { id: 1, url: [12, true] } });
     }).toThrow();
+  });
 
+  test("props are validated in dev mode (code snapshot)", async () => {
+    env.qweb.addTemplates(`
+      <templates>
+        <div t-name="App">
+          <Child message="1"/>
+        </div>
+        <div t-name="Child"><t t-esc="props.message"/></div>
+      </templates>`);
+
+    class Child extends Widget {
+      static props = ["message"];
+    }
+    class App extends Widget {
+      static components = { Child };
+    }
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div>1</div></div>");
+    // need to make sure there are 2 call to update props. one at component
+    // creation, and one at update time.
+    expect(env.qweb.templates.App.fn.toString()).toMatchSnapshot();
+  });
+
+  test("props: list of strings with optional props", async () => {
+    class TestWidget extends Widget {
+      static props = ["message", "someProp?"];
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { someProp: 1 });
+    }).toThrow();
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: 1 });
+    }).not.toThrow();
+  });
+
+  test("props: can be defined with a boolean", async () => {
+    class TestWidget extends Widget {
+      static props = { message: true };
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, {});
+    }).toThrow();
+  });
+
+  test("props: extra props cause an error", async () => {
+    class TestWidget extends Widget {
+      static props = ["message"];
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: 1, flag: true });
+    }).toThrow();
+  });
+
+  test("props: extra props cause an error, part 2", async () => {
+    class TestWidget extends Widget {
+      static props = { message: true };
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: 1, flag: true });
+    }).toThrow();
+  });
+
+  test("props: optional prop do not cause an error", async () => {
+    class TestWidget extends Widget {
+      static props = ["message?"];
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: 1 });
+    }).not.toThrow();
+  });
+
+  test("optional prop do not cause an error if value is undefined", async () => {
+    class TestWidget extends Widget {
+      static props = { message: { type: String, optional: true } };
+    }
+
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: undefined });
+    }).not.toThrow();
+    expect(() => {
+      QWeb.utils.validateProps(TestWidget, { message: null });
+    }).toThrow();
   });
 });
 
-
 describe("default props", () => {
   test("can set default values", async () => {
     class TestWidget extends Widget {
-      static defaultProps = {p: 4}
+      static defaultProps = { p: 4 };
+      static template = xml`<div>hey</div>`;
     }
 
     const w = new TestWidget(env, {});
@@ -253,11 +337,38 @@ describe("default props", () => {
 
   test("default values are also set whenever component is updated", async () => {
     class TestWidget extends Widget {
-      static defaultProps = {p: 4}
+      static template = xml`<div><t t-esc="props.p"/></div>`;
+      static defaultProps = { p: 4 };
+    }
+    class Parent extends Widget {
+      static template = xml`<div><TestWidget p="state.p"/></div>`;
+      static components = { TestWidget };
+      state: any = useState({ p: 1 });
     }
 
-    const w = new TestWidget(env, {p: 1});
-    await w._updateProps({});
-    expect(w.props.p).toBe(4);
+    const w = new Parent(env);
+    await w.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div>1</div></div>");
+
+    w.state.p = undefined;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><div>4</div></div>");
+  });
+
+  test("can set default required boolean values", async () => {
+    class TestWidget extends Widget {
+      static props = ["p", "q"];
+      static defaultProps = { p: true, q: false };
+      static template = xml`<span><t t-if="props.p">hey</t><t t-if="!props.q">hey</t></span>`;
+    }
+
+    class App extends Widget {
+      static template = xml`<div><TestWidget/></div>`;
+      static components = { TestWidget };
+    }
+
+    const w = new App(env, {});
+    await w.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>heyhey</span></div>");
   });
 });

tests/context.test.ts

@@ -0,0 +1,224 @@
+import { makeDeferred, makeTestEnv, makeTestFixture, nextTick } from "./helpers";
+import { Component, Env } from "../src/component/component";
+import { Context, useContext } from "../src/context";
+import { xml } from "../src/tags";
+import { useState } from "../src/hooks";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+// We create before each test:
+// - fixture: a div, appended to the DOM, intended to be the target of dom
+//   manipulations.  Note that it is removed after each test.
+// - env: a WEnv, necessary to create new components
+
+let fixture: HTMLElement;
+let env: Env;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+  env = makeTestEnv();
+});
+
+afterEach(() => {
+  fixture.remove();
+});
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+describe("Context", () => {
+  test("very simple use, with initial value", async () => {
+    const testContext = new Context({ value: 123 });
+
+    class Test extends Component<any, any> {
+      static template = xml`<div><t t-esc="contextObj.value"/></div>`;
+      contextObj = useContext(testContext);
+    }
+    const test = new Test(env);
+    await test.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>123</div>");
+  });
+
+  test("useContext hook is reactive, for one component", async () => {
+    const testContext = new Context({ value: 123 });
+
+    class Test extends Component<any, any> {
+      static template = xml`<div><t t-esc="contextObj.value"/></div>`;
+      contextObj = useContext(testContext);
+    }
+    const test = new Test(env);
+    await test.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>123</div>");
+    test.contextObj.value = 321;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>321</div>");
+  });
+
+  test("two components can subscribe to same context", async () => {
+    const testContext = new Context({ value: 123 });
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="contextObj.value"/></span>`;
+      contextObj = useContext(testContext);
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child /><Child /></div>`;
+      static components = { Child };
+    }
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>123</span><span>123</span></div>");
+    testContext.state.value = 321;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>321</span><span>321</span></div>");
+  });
+
+  test("one components can subscribe twice to same context", async () => {
+    const testContext = new Context({ a: 1, b: 2 });
+    const steps: string[] = [];
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="contextObj1.a"/><t t-esc="contextObj2.b"/></span>`;
+      contextObj1 = useContext(testContext);
+      contextObj2 = useContext(testContext);
+      __render(fiber) {
+        steps.push("child");
+        return super.__render(fiber);
+      }
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child /></div>`;
+      static components = { Child };
+    }
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>12</span></div>");
+    expect(steps).toEqual(["child"]);
+    testContext.state.a = 3;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>32</span></div>");
+    expect(steps).toEqual(["child", "child"]);
+  });
+
+  test("parent and children subscribed to same context", async () => {
+    const testContext = new Context({ a: 123, b: 321 });
+    const steps: string[] = [];
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="contextObj.a"/></span>`;
+      contextObj = useContext(testContext);
+      __render(fiber) {
+        steps.push("child");
+        return super.__render(fiber);
+      }
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child /><t t-esc="contextObj.b"/></div>`;
+      static components = { Child };
+      contextObj = useContext(testContext);
+      __render(fiber) {
+        steps.push("parent");
+        return super.__render(fiber);
+      }
+    }
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>123</span>321</div>");
+    expect(steps).toEqual(["parent", "child"]);
+
+    parent.contextObj.a = 124;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>124</span>321</div>");
+
+    // we only  want one render from the child here, not two
+    expect(steps).toEqual(["parent", "child", "parent", "child"]);
+  });
+
+  test("destroyed component is inactive", async () => {
+    const testContext = new Context({ a: 123 });
+    const steps: string[] = [];
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="contextObj.a"/></span>`;
+      contextObj = useContext(testContext);
+      __render(fiber) {
+        steps.push("child");
+        return super.__render(fiber);
+      }
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child t-if="state.flag"/></div>`;
+      static components = { Child };
+      state = useState({ flag: true });
+      __render(fiber) {
+        steps.push("parent");
+        return super.__render(fiber);
+      }
+    }
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>123</span></div>");
+    expect(steps).toEqual(["parent", "child"]);
+    expect(testContext.subscriptions.update.length).toBe(1);
+
+    parent.state.flag = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+    expect(steps).toEqual(["parent", "child", "parent"]);
+    // kind of whitebox...
+    // we make sure we do not have any pending subscriptions to the 'update'
+    // event
+    expect(testContext.subscriptions.update.length).toBe(0);
+  });
+
+  test("concurrent renderings", async () => {
+    const testContext = new Context({ x: { n: 1 }, key: "x" });
+    const def = makeDeferred();
+    let stateC;
+    class ComponentC extends Component<any, any> {
+      static template = xml`<span><t t-esc="context[props.key].n"/><t t-esc="state.x"/></span>`;
+      context = useContext(testContext);
+      state = useState({ x: "a" });
+
+      constructor(parent, props) {
+        super(parent, props);
+        stateC = this.state;
+      }
+    }
+    class ComponentB extends Component<any, any> {
+      static components = { ComponentC };
+      static template = xml`<p><ComponentC key="props.key"/></p>`;
+
+      willUpdateProps() {
+        return def;
+      }
+    }
+    class ComponentA extends Component<any, any> {
+      static components = { ComponentB };
+      static template = xml`<div><ComponentB key="context.key"/></div>`;
+      context = useContext(testContext);
+    }
+
+    const component = new ComponentA(env);
+    await component.mount(fixture);
+
+    expect(fixture.innerHTML).toBe("<div><p><span>1a</span></p></div>");
+    testContext.state.key = "y";
+    testContext.state.y = {n: 2};
+    delete testContext.state.x;
+    await nextTick();
+
+    expect(fixture.innerHTML).toBe("<div><p><span>1a</span></p></div>");
+    stateC.x = "b";
+    await nextTick();
+
+    expect(fixture.innerHTML).toBe("<div><p><span>1a</span></p></div>");
+    def.resolve();
+    await nextTick();
+
+    expect(fixture.innerHTML).toBe("<div><p><span>2b</span></p></div>");
+  });
+});

tests/core/event_bus.test.ts

@@ -1,4 +1,4 @@
-import { EventBus } from "../src/event_bus";
+import { EventBus } from "../../src/core/event_bus";
 
 describe("event bus behaviour", () => {
   test("can subscribe and be notified", () => {
@@ -23,9 +23,7 @@ describe("event bus behaviour", () => {
   test("throw error if callback is undefined", () => {
     expect.assertions(1);
     const bus = new EventBus();
-    expect(() => bus.on("event", {}, <any>undefined)).toThrow(
-      `Missing callback`
-    );
+    expect(() => bus.on("event", {}, <any>undefined)).toThrow(`Missing callback`);
   });
 
   test("can unsubscribe", () => {

tests/core/observer.test.ts

@@ -0,0 +1,466 @@
+import { Observer } from "../../src/core/observer";
+import { nextMicroTick } from "../helpers";
+
+describe("observer", () => {
+  test("properly observe objects", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({});
+
+    expect(typeof obj).toBe("object");
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    const obj2: any = observer.observe({ a: 1 });
+    expect(observer.revNumber(obj2)).toBe(1);
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    obj2.a = 2;
+
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.revNumber(obj2)).toBe(2);
+    expect(observer.rev).toBe(2);
+
+    expect(obj2).toEqual({
+      a: 2
+    });
+  });
+
+  test("properly handle null or undefined", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ a: null, b: undefined });
+
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    obj.a = 3;
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+
+    obj.b = 5;
+    expect(observer.revNumber(obj)).toBe(3);
+    expect(observer.deepRevNumber(obj)).toBe(3);
+    expect(observer.rev).toBe(3);
+
+    obj.a = null;
+    obj.b = undefined;
+    expect(observer.revNumber(obj)).toBe(5);
+    expect(observer.deepRevNumber(obj)).toBe(5);
+    expect(observer.rev).toBe(5);
+    expect(obj).toEqual({
+      a: null,
+      b: undefined
+    });
+  });
+
+  test("properly handle dates", () => {
+    const observer = new Observer();
+    const date = new Date();
+    const obj: any = observer.observe({ date });
+
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+    expect(typeof obj.date.getFullYear()).toBe("number");
+    expect(obj.date).toBe(date);
+
+    obj.date = new Date();
+
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+    expect(obj.date).not.toBe(date);
+  });
+
+  test("can change values in array", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ arr: [1, 2] });
+
+    expect(Array.isArray(obj.arr)).toBe(true);
+    expect(observer.revNumber(obj.arr)).toBe(1);
+    expect(observer.deepRevNumber(obj.arr)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    obj.arr[0] = "nope";
+    expect(observer.revNumber(obj.arr)).toBe(2);
+    expect(observer.deepRevNumber(obj.arr)).toBe(2);
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+  });
+
+  test("various object property changes", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ a: 1 });
+
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    obj.a = 2;
+
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+
+    // same value again
+    obj.a = 2;
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+
+    obj.a = 3;
+    expect(observer.revNumber(obj)).toBe(3);
+    expect(observer.deepRevNumber(obj)).toBe(3);
+    expect(observer.rev).toBe(3);
+  });
+
+  test("properly observe arrays", () => {
+    const observer = new Observer();
+    const arr: any = observer.observe([]);
+
+    expect(Array.isArray(arr)).toBe(true);
+    expect(arr.length).toBe(0);
+    expect(observer.revNumber(arr)).toBe(1);
+    expect(observer.deepRevNumber(arr)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    arr.push(1);
+    expect(observer.revNumber(arr)).toBe(2);
+    expect(observer.deepRevNumber(arr)).toBe(2);
+    expect(observer.rev).toBe(2);
+    expect(arr.length).toBe(1);
+    expect(arr).toEqual([1]);
+
+    arr.splice(1, 0, "hey");
+    expect(observer.revNumber(arr)).toBe(3);
+    expect(observer.deepRevNumber(arr)).toBe(3);
+    expect(observer.rev).toBe(3);
+    expect(arr).toEqual([1, "hey"]);
+    expect(arr.length).toBe(2);
+
+    arr.unshift("lindemans");
+    //it generates 3 primitive operations
+    expect(observer.revNumber(arr)).toBe(6);
+    expect(observer.deepRevNumber(arr)).toBe(6);
+    expect(observer.rev).toBe(6);
+    expect(arr).toEqual(["lindemans", 1, "hey"]);
+    expect(arr.length).toBe(3);
+
+    arr.reverse();
+    //it generates 2 primitive operations
+    expect(observer.revNumber(arr)).toBe(8);
+    expect(observer.deepRevNumber(arr)).toBe(8);
+    expect(observer.rev).toBe(8);
+    expect(arr).toEqual(["hey", 1, "lindemans"]);
+    expect(arr.length).toBe(3);
+
+    arr.pop(); // one set, one delete
+    expect(observer.revNumber(arr)).toBe(10);
+    expect(observer.deepRevNumber(arr)).toBe(10);
+    expect(observer.rev).toBe(10);
+    expect(arr).toEqual(["hey", 1]);
+    expect(arr.length).toBe(2);
+
+    arr.shift(); // 2 sets, 1 delete
+    expect(observer.revNumber(arr)).toBe(13);
+    expect(observer.deepRevNumber(arr)).toBe(13);
+    expect(observer.rev).toBe(13);
+    expect(arr).toEqual([1]);
+    expect(arr.length).toBe(1);
+  });
+
+  test("object pushed into arrays are observed", () => {
+    const observer = new Observer();
+    const arr: any = observer.observe([]);
+    expect(observer.rev).toBe(1);
+
+    arr.push({ kriek: 5 });
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(arr)).toBe(2);
+    expect(observer.revNumber(arr[0])).toBe(2);
+
+    arr[0].kriek = 6;
+
+    expect(observer.rev).toBe(3);
+    expect(observer.revNumber(arr)).toBe(2);
+    expect(observer.deepRevNumber(arr)).toBe(3);
+    expect(observer.revNumber(arr[0])).toBe(3);
+  });
+
+  test("set new property on observed object", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = observer.observe({ a: 1 });
+    expect(observer.notifyCB).toBeCalledTimes(0);
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state)).toBe(1);
+
+    state.b = 8;
+
+    await nextMicroTick();
+
+    expect(observer.notifyCB).toBeCalledTimes(1);
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state)).toBe(2);
+
+    expect(state.b).toBe(8);
+  });
+
+  test("delete property from observed object", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = observer.observe({ a: 1, b: 8 });
+    observer.observe(state);
+
+    expect(observer.notifyCB).toBeCalledTimes(0);
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state)).toBe(1);
+
+    delete state.b;
+    await nextMicroTick();
+
+    expect(observer.notifyCB).toBeCalledTimes(1);
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state)).toBe(2);
+
+    expect(state).toEqual({ a: 1 });
+  });
+
+  test("set element in observed array", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = observer.observe(["a"]);
+
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.deepRevNumber(state)).toBe(1);
+    expect(observer.notifyCB).toBeCalledTimes(0);
+
+    state[1] = "b";
+
+    await nextMicroTick();
+
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state)).toBe(2);
+    expect(observer.deepRevNumber(state)).toBe(2);
+    expect(observer.notifyCB).toBeCalledTimes(1);
+
+    expect(state).toEqual(["a", "b"]);
+  });
+
+  test("properly observe arrays in object", () => {
+    const observer = new Observer();
+    const state: any = observer.observe({ arr: [] });
+
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state.arr)).toBe(1);
+    expect(observer.deepRevNumber(state.arr)).toBe(1);
+    expect(state.arr.length).toBe(0);
+
+    state.arr.push(1);
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state.arr)).toBe(2);
+    expect(observer.deepRevNumber(state.arr)).toBe(2);
+    expect(state.arr.length).toBe(1);
+  });
+
+  test("properly observe objects in array", () => {
+    const observer = new Observer();
+    const state: any = observer.observe({ arr: [{ something: 1 }] });
+    observer.observe(state);
+
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state.arr)).toBe(1);
+    expect(observer.revNumber(state.arr[0])).toBe(1);
+
+    state.arr[0].something = 2;
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state.arr)).toBe(1);
+    expect(observer.revNumber(state.arr[0])).toBe(2);
+  });
+
+  test("properly observe objects in object", () => {
+    const observer = new Observer();
+    const state: any = observer.observe({ a: { b: 1 } });
+
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.revNumber(state.a)).toBe(1);
+
+    state.a.b = 2;
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.revNumber(state.a)).toBe(2);
+  });
+
+  test("reobserve new object values", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ a: 1 });
+
+    expect(observer.rev).toBe(1);
+    expect(observer.revNumber(obj)).toBe(1);
+
+    obj.a = { b: 2 };
+
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.revNumber(obj.a)).toBe(2);
+    obj.a.b = 3;
+    expect(observer.rev).toBe(3);
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.revNumber(obj.a)).toBe(3);
+  });
+
+  test("deep observe misc changes", () => {
+    const observer = new Observer();
+    const state: any = observer.observe({ o: { a: 1 }, arr: [1], n: 13 });
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.deepRevNumber(state)).toBe(1);
+
+    state.o.a = 2;
+    expect(observer.rev).toBe(2);
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.deepRevNumber(state)).toBe(2);
+
+    state.arr.push(2);
+    expect(observer.rev).toBe(3);
+    expect(observer.revNumber(state)).toBe(1);
+    expect(observer.deepRevNumber(state)).toBe(3);
+
+    state.n = 155;
+    expect(observer.rev).toBe(4);
+    expect(observer.revNumber(state)).toBe(2);
+    expect(observer.deepRevNumber(state)).toBe(4);
+  });
+
+  test("properly handle already observed state", () => {
+    const observer = new Observer();
+    const obj1: any = observer.observe({ a: 1 });
+    const obj2: any = observer.observe({ b: 1 });
+
+    expect(observer.revNumber(obj1)).toBe(1);
+    expect(observer.revNumber(obj2)).toBe(1);
+
+    obj1.a = 2;
+    obj2.b = 3;
+    expect(observer.revNumber(obj1)).toBe(2);
+    expect(observer.revNumber(obj2)).toBe(2);
+
+    obj2.b = obj1;
+    expect(observer.revNumber(obj1)).toBe(2);
+    expect(observer.revNumber(obj2)).toBe(3);
+  });
+
+  test("can set a property more than once", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({});
+
+    expect(observer.revNumber(obj)).toBe(1);
+    expect(observer.deepRevNumber(obj)).toBe(1);
+    expect(observer.rev).toBe(1);
+
+    obj.aku = "always finds annoying problems";
+    expect(observer.revNumber(obj)).toBe(2);
+    expect(observer.deepRevNumber(obj)).toBe(2);
+    expect(observer.rev).toBe(2);
+
+    obj.aku = "always finds good problems";
+
+    expect(observer.revNumber(obj)).toBe(3);
+    expect(observer.deepRevNumber(obj)).toBe(3);
+    expect(observer.rev).toBe(3);
+  });
+
+  test("properly handle swapping elements", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ a: { arr: [] }, b: 1 });
+
+    // swap a and b
+    const b = obj.b;
+    obj.b = obj.a;
+    obj.a = b;
+    expect(observer.rev).toBe(3);
+
+    // push something into array to make sure it works
+    obj.b.arr.push("blanche");
+    expect(observer.rev).toBe(4);
+  });
+
+  test("properly handle assigning observed obj containing array", () => {
+    const observer = new Observer();
+    const obj: any = observer.observe({ a: { arr: [], val: "test" } });
+
+    expect(observer.rev).toBe(1);
+    obj.a = { ...obj.a, val: "test2" };
+    expect(observer.rev).toBe(2);
+
+    // push something into array to make sure it works
+    obj.a.arr.push("blanche");
+    expect(observer.rev).toBe(3);
+  });
+
+  test("accept cycles in observed state", () => {
+    const observer = new Observer();
+    let obj1: any = {};
+    let obj2: any = { b: obj1, key: 1 };
+    obj1.a = obj2;
+    obj1 = observer.observe(obj1);
+    obj2 = obj1.a;
+
+    expect(observer.revNumber(obj1)).toBe(1);
+    expect(observer.revNumber(obj2)).toBe(1);
+
+    obj2.key = 3;
+    expect(observer.revNumber(obj1)).toBe(1);
+    expect(observer.revNumber(obj2)).toBe(2);
+  });
+
+  test("call callback when state is changed", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const obj: any = observer.observe({ a: 1, b: { c: 2 }, d: [{ e: 3 }], f: 4 });
+
+    expect(observer.notifyCB).toBeCalledTimes(0);
+
+    obj.a = 2;
+    await nextMicroTick();
+    expect(observer.notifyCB).toBeCalledTimes(1);
+
+    obj.b.c = 3;
+    await nextMicroTick();
+    expect(observer.notifyCB).toBeCalledTimes(2);
+
+    obj.d[0].e = 5;
+    await nextMicroTick();
+    expect(observer.notifyCB).toBeCalledTimes(3);
+
+    obj.a = 111;
+    obj.f = 222;
+    await nextMicroTick();
+    expect(observer.notifyCB).toBeCalledTimes(4);
+  });
+
+  test("throw error when state is mutated in object if allowMutation=false", async () => {
+    const observer = new Observer();
+    observer.allowMutations = false;
+    const obj: any = observer.observe({ a: 1 });
+    expect(() => {
+      obj.a = 2;
+    }).toThrow('Observed state cannot be changed here! (key: "a", val: "2")');
+  });
+
+  test("throw error when state is mutated in array if allowMutation=false", async () => {
+    const observer = new Observer();
+    observer.allowMutations = false;
+    const obj: any = observer.observe({ a: [1] });
+
+    expect(() => {
+      obj.a.push(2);
+    }).toThrow('Observed state cannot be changed here! (key: "1", val: "2")');
+  });
+});

tests/doc_link_checker.test.ts

@@ -13,7 +13,8 @@ const HEADING_REGEXP = /\n(#+\s*)(.*)/g;
 function getFiles(): string[] {
   const DOCFILES = fs.readdirSync("doc").map(f => `doc/${f}`);
   const MAINREADME = "README.md";
-  return DOCFILES.concat(MAINREADME);
+  DOCFILES.push("roadmap.md", MAINREADME);
+  return DOCFILES;
 }
 
 test("All markdown links work", () => {
@@ -52,15 +53,15 @@ interface FileData {
   sections: MarkDownSection[];
 }
 
-function isLinkValid(
-  link: MarkDownLink,
-  current: FileData,
-  files: FileData[]
-): boolean {
+function isLinkValid(link: MarkDownLink, current: FileData, files: FileData[]): boolean {
+  if (link.link.startsWith("http")) {
+    // no check on external links
+    return true;
+  }
   const parts = link.link.split("#");
   const currentParts = current.name.split("/");
-  const path = currentParts.length > 1 ? currentParts[0] + '/' : "";
-  const fullName =  path + parts[0];
+  const path = currentParts.length > 1 ? currentParts[0] + "/" : "";
+  const fullName = path + parts[0];
   if (parts.length === 1) {
     // no # in url
     if (parts[0].endsWith(".md")) {
@@ -70,8 +71,7 @@ function isLinkValid(
       }
     }
   } else {
-    const file =
-      parts[0] === "" ? current : files.find(f => f.name === fullName);
+    const file = parts[0] === "" ? current : files.find(f => f.name === fullName);
     if (!file) {
       return false;
     }

tests/helpers.ts

@@ -1,15 +1,45 @@
-import { Env } from "../src/component";
-import { EvalContext, QWeb, UTILS } from "../src/qweb_core";
+import { Env, scheduler } from "../src/component/component";
+import { EvalContext, QWeb } from "../src/qweb/qweb";
 import { patch } from "../src/vdom";
-import "../src/qweb_directives";
-import "../src/qweb_extensions";
+import "../src/qweb/base_directives";
+import "../src/qweb/extensions";
+import "../src/component/directive";
 
+// modifies scheduler to make it faster to test components
+scheduler.requestAnimationFrame = function(callback: FrameRequestCallback) {
+  setTimeout(callback, 1);
+  return 1;
+};
+
+// Some static cleanup
+let nextSlotId;
+let slots;
+let nextId;
+let TEMPLATES;
+
+beforeEach(() => {
+  nextSlotId = QWeb.nextSlotId;
+  slots = Object.assign({}, QWeb.slots);
+  nextId = QWeb.nextId;
+  TEMPLATES = Object.assign({}, QWeb.TEMPLATES);
+});
+
+afterEach(() => {
+  QWeb.nextSlotId = nextSlotId;
+  QWeb.slots = slots;
+  QWeb.nextId = nextId;
+  QWeb.TEMPLATES = TEMPLATES;
+});
+
+// helpers
 export function nextMicroTick(): Promise<void> {
   return Promise.resolve();
 }
 
-export function nextTick(): Promise<void> {
-  return new Promise(resolve => setTimeout(resolve));
+export async function nextTick(): Promise<void> {
+  return new Promise(function(resolve) {
+    setTimeout(() => scheduler.requestAnimationFrame(() => resolve()));
+  });
 }
 
 export function makeTestFixture() {
@@ -68,34 +98,45 @@ export function renderToDOM(
   return result.elm as HTMLElement;
 }
 
+/**
+ * Render a template to an html string. The big difference with the
+ * renderToString method in QWeb is that we use the renderToDom method, which
+ * snapshots the resulting template function.  Doing so gives us a large body
+ * of reference to evaluate changes in the generated QWeb code.
+ *
+ * Note that the result of renderToString is guaranteed to be the same as the
+ * one from QWeb.
+ */
 export function renderToString(
   qweb: QWeb,
   t: string,
-  context: EvalContext = {}
+  context: EvalContext = {},
+  extra?: any
 ): string {
-  const node = renderToDOM(qweb, t, context);
-  return node instanceof Text ? node.textContent! : node.outerHTML;
+  const node = renderToDOM(qweb, t, context, extra);
+  const result = node instanceof Text ? node.textContent! : node.outerHTML;
+  if (result !== qweb.renderToString(t, context, extra)) {
+    throw new Error("HTML string returned by renderToString helper does not match QWeb render");
+  }
+  return result;
 }
 
 // hereafter, we define two helpers to patch/unpatch the nextFrame utils. This
 // is useful for animations tests, as we hook before repaints to trigger
 // animations (thanks to requestAnimationFrame). Patching nextFrame allows to
 // simulate calls to this hook. One must not forget to unpatch afterwards.
-let nextFrame = UTILS.nextFrame;
+let nextFrame = QWeb.utils.nextFrame;
 export function patchNextFrame(f: Function) {
-  UTILS.nextFrame = (cb: () => void) => {
+  QWeb.utils.nextFrame = (cb: () => void) => {
     setTimeout(() => f(cb));
   };
 }
 
 export function unpatchNextFrame() {
-  UTILS.nextFrame = nextFrame;
+  QWeb.utils.nextFrame = nextFrame;
 }
 
-export async function editInput(
-  input: HTMLInputElement | HTMLTextAreaElement,
-  value: string
-) {
+export async function editInput(input: HTMLInputElement | HTMLTextAreaElement, value: string) {
   input.value = value;
   input.dispatchEvent(new Event("input"));
   input.dispatchEvent(new Event("change"));

tests/hooks.test.ts

@@ -0,0 +1,493 @@
+import { makeTestEnv, makeTestFixture, nextTick } from "./helpers";
+import { Component, Env } from "../src/component/component";
+import {
+  useState,
+  onMounted,
+  onWillUnmount,
+  useRef,
+  onPatched,
+  onWillPatch,
+  onWillStart,
+  onWillUpdateProps,
+  useSubEnv
+} from "../src/hooks";
+import { xml } from "../src/tags";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+// We create before each test:
+// - fixture: a div, appended to the DOM, intended to be the target of dom
+//   manipulations.  Note that it is removed after each test.
+// - env: a WEnv, necessary to create new components
+
+let fixture: HTMLElement;
+let env: Env;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+  env = makeTestEnv();
+});
+
+afterEach(() => {
+  fixture.remove();
+});
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+describe("hooks", () => {
+  test("can use a state hook", async () => {
+    class Counter extends Component<any, any> {
+      static template = xml`<div><t t-esc="counter.value"/></div>`;
+      counter = useState({ value: 42 });
+    }
+    const counter = new Counter(env);
+    await counter.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>42</div>");
+    counter.counter.value = 3;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>3</div>");
+  });
+
+  test("can use onMounted, onWillUnmount", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onMounted(() => {
+        steps.push("mounted");
+      });
+      onWillUnmount(() => {
+        steps.push("willunmount");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey</div>`;
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+    }
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(component).not.toHaveProperty("mounted");
+    expect(component).not.toHaveProperty("willUnmount");
+    expect(fixture.innerHTML).toBe("<div>hey</div>");
+    expect(steps).toEqual(["mounted"]);
+    component.unmount();
+    expect(fixture.innerHTML).toBe("");
+    expect(steps).toEqual(["mounted", "willunmount"]);
+  });
+
+  test("can use onMounted, onWillUnmount, part 2", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onMounted(() => {
+        steps.push("mounted");
+      });
+      onWillUnmount(() => {
+        steps.push("willunmount");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey</div>`;
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`<div><MyComponent t-if="state.flag"/></div>`;
+      static components = { MyComponent };
+      state = useState({ flag: true });
+    }
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div>hey</div></div>");
+    expect(steps).toEqual(["mounted"]);
+
+    parent.state.flag = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+    expect(steps).toEqual(["mounted", "willunmount"]);
+  });
+
+  test("mounted, willUnmount, onMounted, onWillUnmount order", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onMounted(() => {
+        steps.push("hook:mounted");
+      });
+      onWillUnmount(() => {
+        steps.push("hook:willunmount");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey</div>`;
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+      mounted() {
+        steps.push("comp:mounted");
+      }
+      willUnmount() {
+        steps.push("comp:willunmount");
+      }
+    }
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>hey</div>");
+    component.unmount();
+    expect(fixture.innerHTML).toBe("");
+    expect(steps).toEqual(["comp:mounted", "hook:mounted", "hook:willunmount", "comp:willunmount"]);
+  });
+
+  test("mounted, willUnmount, onMounted, onWillUnmount order, part 2", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onMounted(() => {
+        steps.push("hook:mounted");
+      });
+      onWillUnmount(() => {
+        steps.push("hook:willunmount");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey</div>`;
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+      mounted() {
+        steps.push("comp:mounted");
+      }
+      willUnmount() {
+        steps.push("comp:willunmount");
+      }
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`<div><MyComponent t-if="state.flag"/></div>`;
+      static components = { MyComponent };
+      state = useState({ flag: true });
+    }
+
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div>hey</div></div>");
+    parent.state.flag = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+
+    expect(steps).toEqual(["comp:mounted", "hook:mounted", "hook:willunmount", "comp:willunmount"]);
+  });
+
+  test("two different call to mounted/willunmount should work", async () => {
+    const steps: string[] = [];
+    function useMyHook(i) {
+      onMounted(() => {
+        steps.push("hook:mounted" + i);
+      });
+      onWillUnmount(() => {
+        steps.push("hook:willunmount" + i);
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey</div>`;
+      constructor(env) {
+        super(env);
+        useMyHook(1);
+        useMyHook(2);
+      }
+    }
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>hey</div>");
+    component.unmount();
+    expect(fixture.innerHTML).toBe("");
+    expect(steps).toEqual([
+      "hook:mounted1",
+      "hook:mounted2",
+      "hook:willunmount2",
+      "hook:willunmount1"
+    ]);
+  });
+
+  test("useRef hook", async () => {
+    class Counter extends Component<any, any> {
+      static template = xml`<div><button t-ref="button"><t t-esc="value"/></button></div>`;
+      button = useRef("button");
+      value = 0;
+      increment() {
+        this.value++;
+        (this.button.el as HTMLButtonElement).innerHTML = String(this.value);
+      }
+    }
+    const counter = new Counter(env);
+    await counter.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><button>0</button></div>");
+    counter.increment();
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><button>1</button></div>");
+  });
+
+  test("useRef hook is null if ref is removed ", async () => {
+    expect.assertions(4);
+    class TestRef extends Component<any, any> {
+      static template = xml`<div><span t-if="state.flag" t-ref="span">owl</span></div>`;
+      spanRef = useRef("span");
+      state = useState({ flag: true });
+      willPatch() {
+        expect(this.spanRef.el).not.toBeNull();
+      }
+      patched() {
+        expect(this.spanRef.el).toBeNull();
+      }
+    }
+    const component = new TestRef(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>owl</span></div>");
+    component.state.flag = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+  });
+
+  test("can use onPatched, onWillPatch", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onWillPatch(() => {
+        steps.push("willPatch");
+      });
+      onPatched(() => {
+        steps.push("patched");
+      });
+    }
+
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div><t t-if="state.flag">hey</t></div>`;
+      state = useState({ flag: true });
+
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+    }
+
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(component).not.toHaveProperty("patched");
+    expect(component).not.toHaveProperty("willPatch");
+    expect(steps).toEqual([]);
+
+    expect(fixture.innerHTML).toBe("<div>hey</div>");
+    component.state.flag = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+
+    expect(steps).toEqual(["willPatch", "patched"]);
+  });
+
+  test("patched, willPatch, onPatched, onWillPatch order", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onPatched(() => {
+        steps.push("hook:patched");
+      });
+      onWillPatch(() => {
+        steps.push("hook:willPatch");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div><t t-if="state.flag">hey</t></div>`;
+      state = useState({ flag: true });
+
+      constructor(env) {
+        super(env);
+        useMyHook();
+      }
+      willPatch() {
+        steps.push("comp:willPatch");
+      }
+      patched() {
+        steps.push("comp:patched");
+      }
+    }
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>hey</div>");
+    component.state.flag = false;
+    await nextTick();
+
+    expect(steps).toEqual(["hook:willPatch", "comp:willPatch", "comp:patched", "hook:patched"]);
+  });
+
+  test("two different call to willPatch/patched should work", async () => {
+    const steps: string[] = [];
+    function useMyHook(i) {
+      onPatched(() => {
+        steps.push("hook:patched" + i);
+      });
+      onWillPatch(() => {
+        steps.push("hook:willPatch" + i);
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<div>hey<t t-esc="state.value"/></div>`;
+      state = useState({ value: 1 });
+      constructor(env) {
+        super(env);
+        useMyHook(1);
+        useMyHook(2);
+      }
+    }
+    const component = new MyComponent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>hey1</div>");
+    component.state.value++;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>hey2</div>");
+
+    expect(steps).toEqual(["hook:willPatch2", "hook:willPatch1", "hook:patched1", "hook:patched2"]);
+  });
+
+  describe("autofocus hook", () => {
+    function useAutofocus(name) {
+      let ref = useRef(name);
+      let isInDom = false;
+      function updateFocus() {
+        if (!isInDom && ref.el) {
+          isInDom = true;
+          ref.el.focus();
+        } else if (isInDom && !ref.el) {
+          isInDom = false;
+        }
+      }
+      onPatched(updateFocus);
+      onMounted(updateFocus);
+    }
+
+    test("simple input", async () => {
+      class SomeComponent extends Component<any, any> {
+        static template = xml`
+            <div>
+                <input t-ref="input1"/>
+                <input t-ref="input2"/>
+            </div>`;
+
+        constructor(env) {
+          super(env);
+          useAutofocus("input2");
+        }
+      }
+
+      const component = new SomeComponent(env);
+      await component.mount(fixture);
+      expect(fixture.innerHTML).toBe("<div><input><input></div>");
+      const input2 = fixture.querySelectorAll("input")[1];
+      expect(input2).toBe(document.activeElement);
+    });
+
+    test("input in a t-if", async () => {
+      class SomeComponent extends Component<any, any> {
+        static template = xml`
+            <div>
+                <input t-ref="input1"/>
+                <t t-if="state.flag"><input t-ref="input2"/></t>
+            </div>`;
+
+        state = useState({ flag: false });
+        constructor(env) {
+          super(env);
+          useAutofocus("input2");
+        }
+      }
+
+      const component = new SomeComponent(env);
+      await component.mount(fixture);
+      expect(fixture.innerHTML).toBe("<div><input></div>");
+      expect(document.activeElement).toBe(document.body);
+
+      component.state.flag = true;
+      await nextTick();
+      const input2 = fixture.querySelectorAll("input")[1];
+      expect(input2).toBe(document.activeElement);
+    });
+  });
+
+  test("can use sub env", async () => {
+    class TestComponent extends Component<any, any> {
+      static template = xml`<div><t t-esc="env.val"/></div>`;
+      constructor(env) {
+        super(env);
+        useSubEnv({ val: 3 });
+      }
+    }
+    const component = new TestComponent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>3</div>");
+    expect(env).not.toHaveProperty("val");
+    expect(component.env).toHaveProperty("val");
+  });
+
+  test("parent and child env", async () => {
+    class Child extends Component<any, any> {
+      static template = xml`<div><t t-esc="env.val"/></div>`;
+      constructor(env) {
+        super(env);
+        useSubEnv({ val: 5 });
+      }
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`<div><t t-esc="env.val"/><Child/></div>`;
+      static components = { Child };
+      constructor(env) {
+        super(env);
+        useSubEnv({ val: 3 });
+      }
+    }
+    const component = new Parent(env);
+    await component.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>3<div>5</div></div>");
+  });
+
+  test("can use onWillStart, onWillUpdateProps", async () => {
+    const steps: string[] = [];
+    function useMyHook() {
+      onWillStart(() => {
+        steps.push("onWillStart");
+      });
+      onWillUpdateProps(nextProps => {
+        expect(nextProps).toEqual({ value: 2 });
+        steps.push("onWillUpdateProps");
+      });
+    }
+    class MyComponent extends Component<any, any> {
+      static template = xml`<span><t t-esc="props.value"/></span>`;
+      constructor(parent, props) {
+        super(parent, props);
+        useMyHook();
+      }
+    }
+    class App extends Component<any, any> {
+      static template = xml`<div><MyComponent value="state.value"/></div>`;
+      static components = { MyComponent };
+      state = useState({ value: 1 });
+    }
+
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(app).not.toHaveProperty("willStart");
+    expect(app).not.toHaveProperty("willUpdateProps");
+    expect(fixture.innerHTML).toBe("<div><span>1</span></div>");
+    expect(steps).toEqual(["onWillStart"]);
+
+    app.state.value = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>2</span></div>");
+    expect(steps).toEqual(["onWillStart", "onWillUpdateProps"]);
+  });
+});

tests/misc/async_root.test.ts

@@ -0,0 +1,189 @@
+import { AsyncRoot } from "../../src/misc/async_root";
+import { useState } from "../../src/hooks";
+import { xml } from "../../src/tags";
+import { makeDeferred, makeTestFixture, makeTestEnv, nextTick } from "../helpers";
+import { Env, Component } from "../../src/component/component";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+// We create before each test:
+// - fixture: a div, appended to the DOM, intended to be the target of dom
+//   manipulations.  Note that it is removed after each test.
+// - env: a WEnv, necessary to create new components
+
+let fixture: HTMLElement;
+let env: Env;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+  env = makeTestEnv();
+});
+
+afterEach(() => {
+  fixture.remove();
+});
+
+describe("Asyncroot", () => {
+  test("delayed component with AsyncRoot component", async () => {
+    let def;
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="props.val"/></span>`;
+    }
+    class AsyncChild extends Child {
+      willUpdateProps() {
+        return def;
+      }
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`
+          <div>
+            <button t-on-click="updateApp">Update App State</button>
+            <div class="children">
+              <Child val="state.val"/>
+              <AsyncRoot>
+                  <AsyncChild val="state.val"/>
+              </AsyncRoot>
+            </div>
+          </div>`;
+      static components = { Child, AsyncChild, AsyncRoot };
+      state = useState({ val: 0 });
+
+      updateApp() {
+        this.state.val++;
+      }
+    }
+
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>0</span><span>0</span>");
+
+    // click on button to increment Parent counter
+    def = makeDeferred();
+    fixture.querySelector("button")!.click();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1</span><span>0</span>");
+
+    def.resolve();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1</span><span>1</span>");
+  });
+
+  test("fast component with AsyncRoot", async () => {
+    let def;
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="props.val"/></span>`;
+    }
+    class AsyncChild extends Child {
+      willUpdateProps() {
+        return def;
+      }
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`
+          <div>
+            <button t-on-click="updateApp">Update App State</button>
+            <div class="children">
+              <AsyncRoot>
+                <Child val="state.val"/>
+              </AsyncRoot>
+              <AsyncChild val="state.val"/>
+            </div>
+          </div>`;
+      static components = { Child, AsyncChild, AsyncRoot };
+      state = useState({ val: 0 });
+
+      updateApp() {
+        this.state.val++;
+      }
+    }
+
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>0</span><span>0</span>");
+
+    // click on button to increment Parent counter
+    def = makeDeferred();
+    fixture.querySelector("button")!.click();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1</span><span>0</span>");
+
+    def.resolve();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1</span><span>1</span>");
+  });
+
+  test("asyncroot component: mixed re-renderings", async () => {
+    let def;
+    class Child extends Component<any, any> {
+      static template = xml`
+        <span t-on-click="increment">
+          <t t-esc="state.val"/>/<t t-esc="props.val"/>
+        </span>`;
+      state = useState({ val: 0 });
+
+      increment() {
+        this.state.val++;
+      }
+    }
+    class AsyncChild extends Child {
+      willUpdateProps() {
+        return def;
+      }
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`
+        <div>
+          <button t-on-click="updateApp">Update App State</button>
+          <div class="children">
+            <Child val="state.val"/>
+            <AsyncRoot>
+              <AsyncChild val="state.val"/>
+            </AsyncRoot>
+          </div>
+        </div>`;
+      static components = { Child, AsyncChild, AsyncRoot };
+      state = useState({ val: 0 });
+
+      updateApp() {
+        this.state.val++;
+      }
+    }
+
+    const parent = new Parent(env);
+    await parent.mount(fixture);
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>0/0</span><span>0/0</span>");
+
+    // click on button to increment Parent counter
+    def = makeDeferred();
+    fixture.querySelector("button")!.click();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>0/1</span><span>0/0</span>");
+
+    // click on each Child to increment their local counter
+    const children = parent.el!.querySelectorAll("span");
+    children[0]!.click();
+    await nextTick();
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1/1</span><span>0/0</span>");
+
+    children[1]!.click();
+    await nextTick();
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1/1</span><span>0/0</span>");
+
+    // finalize first re-rendering (coming from the props update)
+    def.resolve();
+    await nextTick();
+
+    expect(fixture.querySelector(".children")!.innerHTML).toBe("<span>1/1</span><span>1/1</span>");
+  });
+});

tests/observer.test.ts

@@ -1,394 +0,0 @@
-import { Observer } from "../src/observer";
-import { nextMicroTick } from "./helpers";
-
-describe("observer", () => {
-  test("properly observe objects", () => {
-    const observer = new Observer();
-    const obj: any = {};
-
-    observer.observe(obj);
-    expect(obj.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-
-    const ob2: any = { a: 1 };
-    observer.observe(ob2);
-    expect(ob2.__owl__.rev).toBe(1);
-    ob2.a = 2;
-    expect(observer.rev).toBe(2);
-    expect(ob2.__owl__.rev).toBe(2);
-
-    ob2.b = 3;
-    expect(observer.rev).toBe(2);
-    expect(ob2.__owl__.rev).toBe(2);
-
-    observer.set(ob2, "b", 4);
-    expect(observer.rev).toBe(3);
-    expect(ob2.__owl__.rev).toBe(3);
-  });
-
-  test("properly handle null or undefined", () => {
-    const observer = new Observer();
-    const obj: any = { a: null, b: undefined };
-
-    observer.observe(obj);
-    expect(obj.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-
-    obj.a = 3;
-    expect(obj.__owl__.rev).toBe(2);
-
-    obj.b = 5;
-    expect(obj.__owl__.rev).toBe(3);
-
-    obj.a = null;
-    obj.b = undefined;
-    expect(obj.__owl__.rev).toBe(5);
-  });
-
-  test("can change values in array", () => {
-    const observer = new Observer();
-    const obj: any = { arr: [1, 2] };
-
-    observer.observe(obj);
-    expect(obj.arr.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-
-    obj.arr[0] = "nope";
-    expect(obj.arr.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-
-    observer.set(obj.arr, 0, "yep");
-    expect(obj.arr.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-  });
-
-  test("various object property changes", () => {
-    const observer = new Observer();
-    const obj: any = { a: 1 };
-    observer.observe(obj);
-    expect(obj.__owl__.rev).toBe(1);
-    obj.a = 2;
-    expect(observer.rev).toBe(2);
-    expect(obj.__owl__.rev).toBe(2);
-
-    // same value again
-    obj.a = 2;
-    expect(observer.rev).toBe(2);
-    expect(obj.__owl__.rev).toBe(2);
-
-    obj.a = 3;
-    expect(observer.rev).toBe(3);
-    expect(obj.__owl__.rev).toBe(3);
-  });
-
-  test("properly observe arrays", () => {
-    const observer = new Observer();
-    const arr: any = [];
-    observer.observe(arr);
-    expect(arr.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(arr.length).toBe(0);
-
-    arr.push(1);
-    expect(arr.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-    expect(arr.length).toBe(1);
-
-    arr.splice(1, 0, "hey");
-    expect(arr.__owl__.rev).toBe(3);
-    expect(observer.rev).toBe(3);
-    expect(arr.length).toBe(2);
-
-    arr.unshift("lindemans");
-    expect(arr.__owl__.rev).toBe(4);
-
-    arr.reverse();
-    expect(arr.__owl__.rev).toBe(5);
-
-    arr.pop();
-    expect(arr.__owl__.rev).toBe(6);
-
-    arr.shift();
-    expect(arr.__owl__.rev).toBe(7);
-
-    arr.sort();
-    expect(arr.__owl__.rev).toBe(8);
-
-    expect(arr).toEqual([1]);
-  });
-
-  test("object pushed into arrays are observed", () => {
-    const observer = new Observer();
-    const arr: any = [];
-    observer.observe(arr);
-    expect(observer.rev).toBe(1);
-
-    arr.push({ kriek: 5 });
-    expect(observer.rev).toBe(2);
-    expect(arr.__owl__.rev).toBe(2);
-    expect(arr[0].__owl__.rev).toBe(2);
-
-    arr[0].kriek = 6;
-    expect(observer.rev).toBe(3);
-    expect(arr.__owl__.rev).toBe(2);
-    expect(arr[0].__owl__.rev).toBe(3);
-  });
-
-  test("set new property on observed object", async () => {
-    const observer = new Observer();
-    observer.notifyCB = jest.fn();
-    const state: any = { a: 1 };
-    observer.observe(state);
-    expect(state.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(observer.notifyCB).toBeCalledTimes(0);
-
-    Observer.set(state, "b", 8);
-    await nextMicroTick();
-    expect(state.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-    expect(observer.notifyCB).toBeCalledTimes(1);
-    expect(state.b).toBe(8);
-  });
-
-  test("delete property from observed object", async () => {
-    const observer = new Observer();
-    observer.notifyCB = jest.fn();
-    const state: any = { a: 1, b: 8 };
-    observer.observe(state);
-    expect(state.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(observer.notifyCB).toBeCalledTimes(0);
-
-    Observer.delete(state, "b");
-    await nextMicroTick();
-    expect(state.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-    expect(observer.notifyCB).toBeCalledTimes(1);
-    expect(state).toEqual({ a: 1 });
-  });
-
-  test("set element in observed array", async () => {
-    const observer = new Observer();
-    observer.notifyCB = jest.fn();
-    const state: any = ["a"];
-    observer.observe(state);
-    expect(state.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(observer.notifyCB).toBeCalledTimes(0);
-
-    Observer.set(state, 1, "b");
-    await nextMicroTick();
-    expect(state.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-    expect(observer.notifyCB).toBeCalledTimes(1);
-    expect(state).toEqual(["a", "b"]);
-  });
-
-  test("properly observe arrays in object", () => {
-    const observer = new Observer();
-    const state: any = { arr: [] };
-    observer.observe(state);
-    expect(state.arr.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(state.arr.length).toBe(0);
-
-    state.arr.push(1);
-    expect(state.arr.__owl__.rev).toBe(2);
-    expect(observer.rev).toBe(2);
-    expect(state.arr.length).toBe(1);
-  });
-
-  test("properly observe objects in array", () => {
-    const observer = new Observer();
-    const state: any = { arr: [{ something: 1 }] };
-    observer.observe(state);
-    expect(state.arr.__owl__.rev).toBe(1);
-    expect(state.arr[0].__owl__.rev).toBe(1);
-
-    state.arr[0].something = 2;
-    expect(state.arr.__owl__.rev).toBe(1);
-    expect(state.arr[0].__owl__.rev).toBe(2);
-  });
-
-  test("properly observe objects in object", () => {
-    const observer = new Observer();
-    const state: any = { a: { b: 1 } };
-    observer.observe(state);
-    expect(state.__owl__.rev).toBe(1);
-    expect(state.a.__owl__.rev).toBe(1);
-
-    state.a.b = 2;
-    expect(state.__owl__.rev).toBe(1);
-    expect(state.a.__owl__.rev).toBe(2);
-  });
-
-  test("reobserve new object values", () => {
-    const observer = new Observer();
-    const obj: any = { a: 1 };
-    observer.observe(obj);
-    expect(obj.__owl__.rev).toBe(1);
-    obj.a = { b: 2 };
-    expect(observer.rev).toBe(2);
-    expect(obj.__owl__.rev).toBe(2);
-
-    // we start at 2 because it is the new observer rev number
-    expect(obj.a.__owl__.rev).toBe(2);
-
-    obj.a.b = 3;
-    expect(observer.rev).toBe(3);
-    expect(obj.__owl__.rev).toBe(2);
-    expect(obj.a.__owl__.rev).toBe(3);
-  });
-
-  test("deep observe misc changes", () => {
-    const observer = new Observer();
-    const state: any = { o: { a: 1 }, arr: [1], n: 13 };
-    observer.observe(state);
-    expect(state.__owl__.rev).toBe(1);
-    expect(state.__owl__.deepRev).toBe(1);
-
-    state.o.a = 2;
-    expect(observer.rev).toBe(2);
-    expect(state.__owl__.rev).toBe(1);
-    expect(state.__owl__.deepRev).toBe(2);
-
-    state.arr.push(2);
-    expect(state.__owl__.rev).toBe(1);
-    expect(state.__owl__.deepRev).toBe(3);
-
-    state.n = 155;
-    expect(state.__owl__.rev).toBe(2);
-    expect(state.__owl__.deepRev).toBe(4);
-  });
-
-  test("properly handle already observed state", () => {
-    const observer = new Observer();
-    const obj1: any = { a: 1 };
-    const obj2: any = { b: 1 };
-    observer.observe(obj1);
-    observer.observe(obj2);
-    expect(obj1.__owl__.rev).toBe(1);
-    expect(obj2.__owl__.rev).toBe(1);
-
-    obj1.a = 2;
-    obj2.b = 3;
-    expect(obj1.__owl__.rev).toBe(2);
-    expect(obj2.__owl__.rev).toBe(2);
-
-    obj2.b = obj1;
-    expect(obj1.__owl__.rev).toBe(2);
-    expect(obj2.__owl__.rev).toBe(3);
-  });
-
-  test("can set a property more than once", () => {
-    const observer = new Observer();
-    const obj: any = {};
-
-    observer.observe(obj);
-    expect(obj.__owl__.rev).toBe(1);
-    expect(observer.rev).toBe(1);
-    expect(obj.__owl__.deepRev).toBe(1);
-
-    observer.set(obj, "aku", "always finds annoying problems");
-    expect(observer.rev).toBe(2);
-    expect(obj.__owl__.rev).toBe(2);
-    expect(obj.__owl__.deepRev).toBe(2);
-
-    observer.set(obj, "aku", "always finds good problems");
-    expect(observer.rev).toBe(3);
-    expect(obj.__owl__.rev).toBe(3);
-    expect(obj.__owl__.deepRev).toBe(3);
-  });
-
-  test("properly handle swapping elements", () => {
-    const observer = new Observer();
-    const obj: any = { a: { arr: [] }, b: 1 };
-    observer.observe(obj);
-
-    // swap a and b
-    const b = obj.b;
-    obj.b = obj.a;
-    obj.a = b;
-    expect(observer.rev).toBe(3);
-
-    // push something into array to make sure it works
-    obj.b.arr.push("blanche");
-    expect(observer.rev).toBe(4);
-  });
-
-  test("properly handle assigning observed obj containing array", () => {
-    const observer = new Observer();
-    const obj: any = { a: { arr: [], val: "test" } };
-    observer.observe(obj);
-
-    obj.a = { ...obj.a, val: "test2" };
-    expect(observer.rev).toBe(2);
-
-    // push something into array to make sure it works
-    obj.a.arr.push("blanche");
-    expect(observer.rev).toBe(3);
-  });
-
-  test("accept cycles in observed state", () => {
-    const observer = new Observer();
-    const obj1: any = {};
-    const obj2: any = { b: obj1, key: 1 };
-    obj1.a = obj2;
-    observer.observe(obj1);
-    expect(obj1.__owl__.rev).toBe(1);
-    expect(obj2.__owl__.rev).toBe(1);
-
-    obj2.key = 3;
-    expect(obj1.__owl__.rev).toBe(1);
-    expect(obj2.__owl__.rev).toBe(2);
-  });
-
-  test("call callback when state is changed", async () => {
-    const observer = new Observer();
-    observer.notifyCB = jest.fn();
-    const obj: any = { a: 1, b: { c: 2 }, d: [{ e: 3 }], f: 4 };
-
-    observer.observe(obj);
-    expect(observer.notifyCB).toBeCalledTimes(0);
-
-    obj.a = 2;
-    await nextMicroTick();
-    expect(observer.notifyCB).toBeCalledTimes(1);
-
-    obj.b.c = 3;
-    await nextMicroTick();
-    expect(observer.notifyCB).toBeCalledTimes(2);
-
-    obj.d[0].e = 5;
-    await nextMicroTick();
-    expect(observer.notifyCB).toBeCalledTimes(3);
-
-    obj.a = 111;
-    obj.f = 222;
-    await nextMicroTick();
-    expect(observer.notifyCB).toBeCalledTimes(4);
-  });
-
-  test("throw error when state is mutated in object if allowMutation=false", async () => {
-    const observer = new Observer();
-    observer.allowMutations = false;
-    const obj: any = { a: 1 };
-    observer.observe(obj);
-
-    expect(() => {
-      obj.a = 2;
-    }).toThrow('Observed state cannot be changed here! (key: "a", val: "2")');
-  });
-
-  test("throw error when state is mutated in array if allowMutation=false", async () => {
-    const observer = new Observer();
-    observer.allowMutations = false;
-    const obj: any = { a: [1] };
-    observer.observe(obj);
-
-    expect(() => {
-      obj.a.push(2);
-    }).toThrow("Array cannot be changed here");
-  });
-});

tests/qweb/qweb.test.ts

@@ -1,5 +1,5 @@
-import { QWeb } from "../src/qweb_core";
-import { normalize, renderToDOM, renderToString, trim } from "./helpers";
+import { QWeb } from "../../src/qweb/index";
+import { normalize, renderToDOM, renderToString, trim, nextTick } from "../helpers";
 
 //------------------------------------------------------------------------------
 // Setup and helpers
@@ -11,6 +11,7 @@ import { normalize, renderToDOM, renderToString, trim } from "./helpers";
 let qweb: QWeb;
 
 beforeEach(() => {
+  QWeb.TEMPLATES = {};
   qweb = new QWeb();
 });
 
@@ -25,13 +26,13 @@ describe("static templates", () => {
   });
 
   test("simple dynamic value", () => {
-    qweb.addTemplate("test", "<t><t t-esc=\"text\"/></t>");
-    expect(renderToString(qweb, "test", {text: "hello vdom"})).toBe("hello vdom");
+    qweb.addTemplate("test", '<t><t t-esc="text"/></t>');
+    expect(renderToString(qweb, "test", { text: "hello vdom" })).toBe("hello vdom");
   });
 
   test("simple string, with some dynamic value", () => {
-    qweb.addTemplate("test", "<t>hello <t t-esc=\"text\"/></t>");
-    expect(renderToString(qweb, "test", {text: "vdom"})).toBe("hello vdom");
+    qweb.addTemplate("test", '<t>hello <t t-esc="text"/></t>');
+    expect(renderToString(qweb, "test", { text: "vdom" })).toBe("hello vdom");
   });
 
   test("empty div", () => {
@@ -48,13 +49,16 @@ describe("static templates", () => {
     qweb.addTemplate("test", "<div><span>word</span></div>");
     expect(renderToString(qweb, "test")).toBe("<div><span>word</span></div>");
   });
+
+  test("properly handle comments", () => {
+    qweb.addTemplate("test", "<div>hello <!-- comment-->owl</div>");
+    expect(renderToString(qweb, "test")).toBe("<div>hello <!-- comment-->owl</div>");
+  });
 });
 
 describe("error handling", () => {
   test("invalid xml", () => {
-    expect(() => qweb.addTemplate("test", "<div>")).toThrow(
-      "Invalid XML in template"
-    );
+    expect(() => qweb.addTemplate("test", "<div>")).toThrow("Invalid XML in template");
   });
 
   test("template with text node and tag", () => {
@@ -71,37 +75,26 @@ describe("error handling", () => {
 
   test("cannot add twice the same template", () => {
     qweb.addTemplate("test", `<t></t>`);
+    expect(() => qweb.addTemplate("test", "<div/>", true)).not.toThrow("already defined");
     expect(() => qweb.addTemplate("test", "<div/>")).toThrow("already defined");
   });
 
-  test("loadTemplates throw if parser error", () => {
+  test("addTemplates throw if parser error", () => {
     expect(() => {
       qweb.addTemplates("<templates><abc>></templates>");
     }).toThrow("Invalid XML in template");
   });
 
-  test("nice error when t-on-directive is evaluated with a missing handler", () => {
-    qweb.addTemplate("templatename", `<div t-on-click="somemethod"></div>`);
-    expect(() => qweb.render("templatename", {}, { handlers: [] })).toThrow(
-      "Missing handler 'somemethod' when evaluating template 'templatename'"
-    );
-  });
-
   test("nice error when t-on is evaluated with a missing event", () => {
     qweb.addTemplate("templatename", `<div t-on="somemethod"></div>`);
-    expect(() =>
-      qweb.render("templatename", { someMethod() {} }, { handlers: [] })
-    ).toThrow("Missing event name with t-on directive");
+    expect(() => qweb.render("templatename", { someMethod() {} }, { handlers: [] })).toThrow(
+      "Missing event name with t-on directive"
+    );
   });
 
   test("error when unknown directive", () => {
-    qweb.addTemplate(
-      "templatename",
-      `<div t-best-beer="rochefort 10">test</div>`
-    );
-    expect(() => qweb.render("templatename")).toThrow(
-      "Unknown QWeb directive: 't-best-beer'"
-    );
+    qweb.addTemplate("templatename", `<div t-best-beer="rochefort 10">test</div>`);
+    expect(() => qweb.render("templatename")).toThrow("Unknown QWeb directive: 't-best-beer'");
   });
 });
 
@@ -118,9 +111,7 @@ describe("t-esc", () => {
 
   test.skip("escaping", () => {
     qweb.addTemplate("test", `<span><t t-esc="var"/></span>`);
-    expect(renderToString(qweb, "test", { var: "<ok>" })).toBe(
-      "<span>&lt;ok&gt;</span>"
-    );
+    expect(renderToString(qweb, "test", { var: "<ok>" })).toBe("<span>&lt;ok&gt;</span>");
   });
 
   test("escaping on a node", () => {
@@ -152,9 +143,7 @@ describe("t-raw", () => {
 
   test("not escaping", () => {
     qweb.addTemplate("test", `<div><t t-raw="var"/></div>`);
-    expect(renderToString(qweb, "test", { var: "<ok></ok>" })).toBe(
-      "<div><ok></ok></div>"
-    );
+    expect(renderToString(qweb, "test", { var: "<ok></ok>" })).toBe("<div><ok></ok></div>");
   });
 
   test("t-raw and another sibling node", () => {
@@ -167,10 +156,7 @@ describe("t-raw", () => {
 
 describe("t-set", () => {
   test("set from attribute literal", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="'ok'"/><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="'ok'"/><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>ok</div>");
   });
 
@@ -182,24 +168,16 @@ describe("t-set", () => {
         <t t-if="v === 'ok'">grimbergen</t>
         </div>`
     );
-    expect(renderToString(qweb, "test", { value: "ok" })).toBe(
-      "<div>grimbergen</div>"
-    );
+    expect(renderToString(qweb, "test", { value: "ok" })).toBe("<div>grimbergen</div>");
   });
 
   test("set from body literal", () => {
-    qweb.addTemplate(
-      "test",
-      `<t><t t-set="value">ok</t><t t-esc="value"/></t>`
-    );
+    qweb.addTemplate("test", `<t><t t-set="value">ok</t><t t-esc="value"/></t>`);
     expect(renderToString(qweb, "test")).toBe("ok");
   });
 
   test("set from attribute lookup", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="stuff" t-value="value"/><t t-esc="stuff"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="stuff" t-value="value"/><t t-esc="stuff"/></div>`);
     expect(renderToString(qweb, "test", { value: "ok" })).toBe("<div>ok</div>");
   });
 
@@ -231,18 +209,12 @@ describe("t-set", () => {
   });
 
   test("value priority", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="1">2</t><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="1">2</t><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>1</div>");
   });
 
   test("evaluate value expression", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="1 + 2"/><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="1 + 2"/><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>3</div>");
   });
 
@@ -267,25 +239,19 @@ describe("t-set", () => {
       "test",
       `<div><t t-set="value" t-value="somevariable + 2"/><t t-esc="value"/></div>`
     );
-    expect(renderToString(qweb, "test", { somevariable: 43 })).toBe(
-      "<div>45</div>"
-    );
+    expect(renderToString(qweb, "test", { somevariable: 43 })).toBe("<div>45</div>");
   });
 });
 
 describe("t-if", () => {
   test("boolean value true condition", () => {
     qweb.addTemplate("test", `<div><t t-if="condition">ok</t></div>`);
-    expect(renderToString(qweb, "test", { condition: true })).toBe(
-      "<div>ok</div>"
-    );
+    expect(renderToString(qweb, "test", { condition: true })).toBe("<div>ok</div>");
   });
 
   test("boolean value false condition", () => {
     qweb.addTemplate("test", `<div><t t-if="condition">ok</t></div>`);
-    expect(renderToString(qweb, "test", { condition: false })).toBe(
-      "<div></div>"
-    );
+    expect(renderToString(qweb, "test", { condition: false })).toBe("<div></div>");
   });
 
   test("boolean value condition missing", () => {
@@ -302,9 +268,7 @@ describe("t-if", () => {
         <t t-else="">beer</t></div>
     `
     );
-    expect(renderToString(qweb, "test", { color: "red" })).toBe(
-      "<div>red is dead</div>"
-    );
+    expect(renderToString(qweb, "test", { color: "red" })).toBe("<div>red is dead</div>");
   });
 
   test("boolean value condition else", () => {
@@ -330,9 +294,7 @@ describe("t-if", () => {
         `
     );
     const result = trim(renderToString(qweb, "test", { condition: false }));
-    expect(result).toBe(
-      "<div><span>begin</span>fail-else<span>end</span></div>"
-    );
+    expect(result).toBe("<div><span>begin</span>fail-else<span>end</span></div>");
   });
 
   test("can use some boolean operators in expressions", () => {
@@ -357,9 +319,62 @@ describe("t-if", () => {
       m: 5,
       n: 2
     };
-    expect(normalize(renderToString(qweb, "test", context))).toBe(
-      "<div>andormgtnlt</div>"
+    expect(normalize(renderToString(qweb, "test", context))).toBe("<div>andormgtnlt</div>");
+  });
+
+  test("t-esc with t-if", () => {
+    qweb.addTemplate("test", `<div><t t-if="true" t-esc="'x'"/></div>`);
+    expect(renderToString(qweb, "test")).toBe("<div>x</div>");
+  });
+
+  test("t-esc with t-elif", () => {
+    qweb.addTemplate("test", `<div><t t-if="false">abc</t><t t-else="1" t-esc="'x'"/></div>`);
+    expect(renderToString(qweb, "test")).toBe("<div>x</div>");
+  });
+
+  test("t-set, then t-if", () => {
+    qweb.addTemplate(
+      "test",
+      `
+      <div>
+        <t t-set="title" t-value="'test'"/>
+        <t t-if="title"><t t-esc="title"/></t>
+      </div>`
     );
+    const result = renderToString(qweb, "test");
+    const expected = `<div>test</div>`;
+    expect(result).toBe(expected);
+  });
+
+  test("t-set, then t-if, part 2", () => {
+    qweb.addTemplate(
+      "test",
+      `
+        <div>
+            <t t-set="y" t-value="true"/>
+            <t t-set="x" t-value="y"/>
+            <span t-if="x">COUCOU</span>
+        </div>`
+    );
+    const result = renderToString(qweb, "test");
+    const expected = `<div><span>COUCOU</span></div>`;
+    expect(result).toBe(expected);
+  });
+
+  test("t-set, then t-elif, part 3", () => {
+    qweb.addTemplate(
+      "test",
+      `
+        <div>
+            <t t-set="y" t-value="false"/>
+            <t t-set="x" t-value="y"/>
+            <span t-if="x">AAA</span>
+            <span t-elif="!x">BBB</span>
+        </div>`
+    );
+    const result = renderToString(qweb, "test");
+    const expected = `<div><span>BBB</span></div>`;
+    expect(result).toBe(expected);
   });
 });
 
@@ -484,10 +499,7 @@ describe("attributes", () => {
   });
 
   test("format multiple", () => {
-    qweb.addTemplate(
-      "test",
-      `<div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>`
-    );
+    qweb.addTemplate("test", `<div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>`);
     const result = renderToString(qweb, "test", {
       value1: 0,
       value2: 1,
@@ -523,19 +535,13 @@ describe("attributes", () => {
   });
 
   test("class and t-attf-class with ternary operation", () => {
-    qweb.addTemplate(
-      "test",
-      `<div class="hello" t-attf-class="{{value ? 'world' : ''}}"/>`
-    );
+    qweb.addTemplate("test", `<div class="hello" t-attf-class="{{value ? 'world' : ''}}"/>`);
     const result = renderToString(qweb, "test", { value: true });
     expect(result).toBe(`<div class="hello world"></div>`);
   });
 
   test("t-att-class with object", () => {
-    qweb.addTemplate(
-      "test",
-      `<div class="static" t-att-class="{a: b, c: d, e: f}"/>`
-    );
+    qweb.addTemplate("test", `<div class="static" t-att-class="{a: b, c: d, e: f}"/>`);
     const result = renderToString(qweb, "test", { b: true, d: false, f: true });
     expect(result).toBe(`<div class="static a e"></div>`);
   });
@@ -549,6 +555,13 @@ describe("t-call (template calling", () => {
     expect(renderToString(qweb, "caller")).toBe(expected);
   });
 
+  test("t-call with t-if", () => {
+    qweb.addTemplate("sub", "<span>ok</span>");
+    qweb.addTemplate("caller", '<div><t t-if="flag" t-call="sub"/></div>');
+    const expected = "<div><span>ok</span></div>";
+    expect(renderToString(qweb, "caller", { flag: true })).toBe(expected);
+  });
+
   test("t-call not allowed on a non t node", () => {
     qweb.addTemplate("_basic-callee", "<t>ok</t>");
     qweb.addTemplate("caller", '<div t-call="_basic-callee"/>');
@@ -564,10 +577,7 @@ describe("t-call (template calling", () => {
 
   test("with unused setbody", () => {
     qweb.addTemplate("_basic-callee", "<div>ok</div>");
-    qweb.addTemplate(
-      "caller",
-      '<t t-call="_basic-callee"><t t-set="qux" t-value="3"/></t>'
-    );
+    qweb.addTemplate("caller", '<t t-call="_basic-callee"><t t-set="qux" t-value="3"/></t>');
     const expected = "<div>ok</div>";
     expect(renderToString(qweb, "caller")).toBe(expected);
   });
@@ -617,6 +627,103 @@ describe("t-call (template calling", () => {
     const expected = "<div>ok</div>";
     expect(trim(renderToString(qweb, "caller"))).toBe(expected);
   });
+
+  test("call with several sub nodes on same line", () => {
+    qweb.addTemplates(`
+        <templates>
+            <div t-name="SubTemplate">
+                <t t-raw="0"/>
+            </div>
+
+            <div t-name="main">
+                <t t-call="SubTemplate">
+                    <span>hey</span> <span>yay</span>
+                </t>
+            </div>
+        </templates>
+    `);
+    const expected = "<div><div><span>hey</span> <span>yay</span></div></div>";
+    expect(renderToString(qweb, "main")).toBe(expected);
+  });
+
+  test("recursive template, part 1", () => {
+    qweb.addTemplates(`
+        <templates>
+            <div t-name="recursive">
+                <span>hey</span>
+                <t t-if="false">
+                    <t t-call="recursive"/>
+                </t>
+            </div>
+        </templates>
+    `);
+    const expected = "<div><span>hey</span></div>";
+    expect(renderToString(qweb, "recursive")).toBe(expected);
+    const recursiveFn = Object.values(qweb.recursiveFns)[0];
+    expect(recursiveFn.toString()).toMatchSnapshot();
+  });
+
+  test("recursive template, part 2", () => {
+    qweb.addTemplates(`
+        <templates>
+            <div t-name="Parent">
+                <t t-call="nodeTemplate">
+                    <t t-set="node" t-value="root"/>
+                </t>
+            </div>
+            <div t-name="nodeTemplate">
+                <p><t t-esc="node.val"/></p>
+                <t t-foreach="node.children or []" t-as="subtree">
+                    <t t-call="nodeTemplate">
+                        <t t-set="node" t-value="subtree"/>
+                    </t>
+                </t>
+            </div>
+
+        </templates>
+    `);
+    const root = { val: "a", children: [{ val: "b" }, { val: "c" }] };
+    const expected = "<div><div><p>a</p><div><p>b</p></div><div><p>c</p></div></div></div>";
+    expect(renderToString(qweb, "Parent", { root }, { fiber: { vars: {}, scope: {} } })).toBe(
+      expected
+    );
+    const recursiveFn = Object.values(qweb.recursiveFns)[0];
+    expect(recursiveFn.toString()).toMatchSnapshot();
+  });
+
+  test("recursive template, part 3", () => {
+    qweb.addTemplates(`
+        <templates>
+            <div t-name="Parent">
+                <t t-call="nodeTemplate">
+                    <t t-set="node" t-value="root"/>
+                </t>
+            </div>
+            <div t-name="nodeTemplate">
+                <p><t t-esc="node.val"/></p>
+                <t t-foreach="node.children or []" t-as="subtree">
+                    <t t-call="nodeTemplate">
+                        <t t-set="node" t-value="subtree"/>
+                    </t>
+                </t>
+            </div>
+
+        </templates>
+    `);
+    const root = { val: "a", children: [{ val: "b", children: [{ val: "d" }] }, { val: "c" }] };
+    const expected =
+      "<div><div><p>a</p><div><p>b</p><div><p>d</p></div></div><div><p>c</p></div></div></div>";
+    expect(renderToString(qweb, "Parent", { root }, { fiber: {} })).toBe(expected);
+    const recursiveFn = Object.values(qweb.recursiveFns)[0];
+    expect(recursiveFn.toString()).toMatchSnapshot();
+  });
+
+  test("t-call, global templates", () => {
+    QWeb.registerTemplate("abcd", '<div><t t-call="john"/></div>');
+    qweb.addTemplate("john", `<span>desk</span>`);
+    const expected = "<div><span>desk</span></div>";
+    expect(trim(renderToString(qweb, "abcd"))).toBe(expected);
+  });
 });
 
 describe("foreach", () => {
@@ -673,9 +780,7 @@ describe("foreach", () => {
         </t>
       </div>`
     );
-    const result = trim(
-      renderToString(qweb, "test", { value: { a: 1, b: 2, c: 3 } })
-    );
+    const result = trim(renderToString(qweb, "test", { value: { a: 1, b: 2, c: 3 } }));
     const expected = `<div>[0:a1][1:b2][2:c3]</div>`;
     expect(result).toBe(expected);
   });
@@ -692,6 +797,23 @@ describe("foreach", () => {
     expect(Object.keys(context).length).toBe(0);
   });
 
+  test("t-foreach in t-forach", () => {
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <t t-foreach="numbers" t-as="number">
+          <t t-foreach="letters" t-as="letter">
+            [<t t-esc="number"/><t t-esc="letter"/>]
+          </t>
+        </t>
+      </div>`
+    );
+    const context = { numbers: [1, 2, 3], letters: ["a", "b"] };
+    expect(renderToString(qweb, "test", context)).toBe(
+      "<div> [1a]  [1b]  [2a]  [2b]  [3a]  [3b] </div>"
+    );
+  });
+
   test("throws error if invalid loop expression", () => {
     qweb.addTemplate(
       "test",
@@ -721,15 +843,9 @@ describe("foreach", () => {
 
 describe("misc", () => {
   test("global", () => {
-    qweb.addTemplate("_callee-asc", `<Año t-att-falló="'agüero'" t-raw="0"/>`);
-    qweb.addTemplate(
-      "_callee-uses-foo",
-      `<span t-esc="foo">foo default</span>`
-    );
-    qweb.addTemplate(
-      "_callee-asc-toto",
-      `<div t-raw="toto">toto default</div>`
-    );
+    qweb.addTemplate("_callee-asc", `<año t-att-falló="'agüero'" t-raw="0"/>`);
+    qweb.addTemplate("_callee-uses-foo", `<span t-esc="foo">foo default</span>`);
+    qweb.addTemplate("_callee-asc-toto", `<div t-raw="toto">toto default</div>`);
     qweb.addTemplate(
       "caller",
       `
@@ -842,10 +958,7 @@ describe("t-on", () => {
   });
 
   test("can bind handlers with object arguments", () => {
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="add({val: 5})">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="add({val: 5})">Click</button>`);
     let a = 1;
     const node = renderToDOM(
       qweb,
@@ -863,10 +976,7 @@ describe("t-on", () => {
 
   test("can bind handlers with empty object", () => {
     expect.assertions(2);
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="doSomething({})">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="doSomething({})">Click</button>`);
     const node = renderToDOM(
       qweb,
       "test",
@@ -882,10 +992,7 @@ describe("t-on", () => {
 
   test("can bind handlers with empty object (with non empty inner string)", () => {
     expect.assertions(2);
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="doSomething({ })">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="doSomething({ })">Click</button>`);
     const node = renderToDOM(
       qweb,
       "test",
@@ -933,6 +1040,33 @@ describe("t-on", () => {
     (<HTMLElement>node).click();
   });
 
+  test("t-on with inline statement", () => {
+    qweb.addTemplate("test", `<button t-on-click="state.counter++">Click</button>`);
+    let owner = {
+      state: {
+        counter: 0,
+      },
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+    expect(owner.state.counter).toBe(0);
+    (<HTMLElement>node).click();
+    expect(owner.state.counter).toBe(1);
+  });
+
+  test("t-on with inline statement (function call)", () => {
+    qweb.addTemplate("test", `<button t-on-click="state.incrementCounter(2)">Click</button>`);
+    let owner = {
+      state: {
+        counter: 0,
+        incrementCounter: (inc) => { owner.state.counter += inc; },
+      },
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+    expect(owner.state.counter).toBe(0);
+    (<HTMLElement>node).click();
+    expect(owner.state.counter).toBe(2);
+  });
+
   test("t-on with prevent and/or stop modifiers", async () => {
     expect.assertions(7);
     qweb.addTemplate(
@@ -1044,20 +1178,110 @@ describe("t-on", () => {
 
     expect(steps).toEqual([true, true]);
   });
+
+  test("t-on with prevent modifier in t-foreach", async () => {
+    expect.assertions(5);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <t t-foreach="projects" t-as="project">
+          <a href="#" t-key="project" t-on-click.prevent="onEdit(project.id)">
+            Edit <t t-esc="project.name"/>
+          </a>
+        </t>
+      </div>`
+    );
+    const steps: string[] = [];
+    const owner = {
+      projects: [{ id: 1, name: "Project 1" }, { id: 2, name: "Project 2" }],
+
+      onEdit(projectId, ev) {
+        expect(ev.defaultPrevented).toBe(true);
+        steps.push(projectId);
+      }
+    };
+
+    const node = <HTMLElement>renderToDOM(qweb, "test", owner, { handlers: [] });
+    expect(node.outerHTML).toBe(
+      `<div><a href="#"> Edit Project 1</a><a href="#"> Edit Project 2</a></div>`
+    );
+
+    const links = node.querySelectorAll("a")!;
+    links[0].click();
+    links[1].click();
+
+    expect(steps).toEqual([1, 2]);
+  });
+
+  test("t-on with empty handler (only modifiers)", () => {
+    expect.assertions(2);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <button t-on-click.prevent="">Button</button>
+      </div>`
+    );
+    const node = renderToDOM(qweb, "test", {}, { handlers: [] });
+
+    node.addEventListener('click', (e) => {
+      expect(e.defaultPrevented).toBe(true);
+    });
+
+    const button = (<HTMLElement>node).getElementsByTagName("button")[0];
+    button.click();
+  });
+
+  test("t-on combined with t-esc", async () => {
+    expect.assertions(3);
+    qweb.addTemplate("test", `<div><button t-on-click="onClick" t-esc="text"/></div>`);
+    const steps: string[] = [];
+    const owner = {
+      text: "Click here",
+      onClick() {
+        steps.push("onClick");
+      }
+    };
+
+    const node = <HTMLElement>renderToDOM(qweb, "test", owner, { handlers: [] });
+    expect(node.outerHTML).toBe(`<div><button>Click here</button></div>`);
+
+    node.querySelector("button")!.click();
+
+    expect(steps).toEqual(["onClick"]);
+  });
+
+  test("t-on combined with t-raw", async () => {
+    expect.assertions(3);
+    qweb.addTemplate("test", `<div><button t-on-click="onClick" t-raw="html"/></div>`);
+    const steps: string[] = [];
+    const owner = {
+      html: "Click <b>here</b>",
+      onClick() {
+        steps.push("onClick");
+      }
+    };
+
+    const node = <HTMLElement>renderToDOM(qweb, "test", owner, { handlers: [] });
+    expect(node.outerHTML).toBe(`<div><button>Click <b>here</b></button></div>`);
+
+    node.querySelector("button")!.click();
+
+    expect(steps).toEqual(["onClick"]);
+  });
 });
 
 describe("t-ref", () => {
   test("can get a ref on a node", () => {
     qweb.addTemplate("test", `<div><span t-ref="myspan"/></div>`);
     let refs: any = {};
-    renderToDOM(qweb, "test", { refs });
+    renderToDOM(qweb, "test", { __owl__: { refs } });
     expect(refs.myspan.tagName).toBe("SPAN");
   });
 
   test("can get a dynamic ref on a node", () => {
     qweb.addTemplate("test", `<div><span t-ref="myspan{{id}}"/></div>`);
     let refs: any = {};
-    renderToDOM(qweb, "test", { refs, id: 3 });
+    renderToDOM(qweb, "test", { id: 3, __owl__: { refs } });
     expect(refs.myspan3.tagName).toBe("SPAN");
   });
 
@@ -1072,7 +1296,7 @@ describe("t-ref", () => {
       </div>`
     );
     let refs: any = {};
-    renderToDOM(qweb, "test", { refs, items: [1, 2, 3] });
+    renderToDOM(qweb, "test", { items: [1, 2, 3], __owl__: { refs } });
     expect(Object.keys(refs)).toEqual(["1", "2", "3"]);
   });
 });
@@ -1185,13 +1409,10 @@ describe("whitespace handling", () => {
 
 describe("t-key", () => {
   test("can use t-key directive on a node", () => {
-    qweb.addTemplate(
-      "test",
-      `<div t-key="beer.id"><t t-esc="beer.name"/></div>`
+    qweb.addTemplate("test", `<div t-key="beer.id"><t t-esc="beer.name"/></div>`);
+    expect(renderToString(qweb, "test", { beer: { id: 12, name: "Chimay Rouge" } })).toBe(
+      "<div>Chimay Rouge</div>"
     );
-    expect(
-      renderToString(qweb, "test", { beer: { id: 12, name: "Chimay Rouge" } })
-    ).toBe("<div>Chimay Rouge</div>");
   });
 
   test("t-key directive in a list", () => {
@@ -1242,3 +1463,57 @@ describe("debugging", () => {
     console.log = consoleLog;
   });
 });
+
+describe("update on event bus", () => {
+  test("two consecutive forceUpdates only causes one listener update", async () => {
+    const fn = jest.fn();
+    qweb.on("update", null, fn);
+    qweb.forceUpdate();
+    qweb.forceUpdate();
+    expect(fn).toBeCalledTimes(0);
+    await nextTick();
+    expect(fn).toBeCalledTimes(1);
+  });
+});
+
+describe("global template registration", () => {
+  test("can register template globally", () => {
+    expect.assertions(5);
+    let qweb = new QWeb();
+    try {
+      qweb.render("mytemplate");
+    } catch (e) {
+      expect(e.message).toMatch("Template mytemplate does not exist");
+    }
+    expect(qweb.templates.mytemplate).toBeUndefined();
+
+    QWeb.registerTemplate("mytemplate", "<div>global</div>");
+    expect(qweb.templates.mytemplate).toBeDefined();
+    const vnode = qweb.render("mytemplate");
+    expect(vnode.sel).toBe("div");
+    expect((vnode as any).children[0].text).toBe("global");
+  });
+});
+
+describe("properly support svg", () => {
+  test("add proper namespace to svg", () => {
+    qweb.addTemplate(
+      "test",
+      `<svg width="100px" height="90px"><circle cx="50" cy="50" r="4" stroke="green" stroke-width="1" fill="yellow"/> </svg>`
+    );
+    expect(renderToString(qweb, "test")).toBe(
+      `<svg width=\"100px\" height=\"90px\"><circle cx=\"50\" cy=\"50\" r=\"4\" stroke=\"green\" stroke-width=\"1\" fill=\"yellow\"></circle> </svg>`
+    );
+  });
+
+  test("add proper namespace to g tags", () => {
+    // this is necessary if one wants to use components in a svg
+    qweb.addTemplate(
+      "test",
+      `<g><circle cx="50" cy="50" r="4" stroke="green" stroke-width="1" fill="yellow"/> </g>`
+    );
+    expect(renderToString(qweb, "test")).toBe(
+      `<g><circle cx=\"50\" cy=\"50\" r=\"4\" stroke=\"green\" stroke-width=\"1\" fill=\"yellow\"></circle> </g>`
+    );
+  });
+});

tests/qweb/qweb_expressions.test.ts

@@ -1,10 +1,8 @@
-import { compileExpr, tokenize } from "../src/qweb_expressions";
+import { compileExpr, tokenize } from "../../src/qweb/expression_parser";
 
 describe("tokenizer", () => {
   test("simple tokens", () => {
-    expect(tokenize("1.3")).toEqual([
-      { type: "VALUE", value: "1.3" }
-    ]);
+    expect(tokenize("1.3")).toEqual([{ type: "VALUE", value: "1.3" }]);
 
     expect(tokenize("{}")).toEqual([
       { type: "LEFT_BRACE", value: "{" },
@@ -29,10 +27,7 @@ describe("tokenizer", () => {
       { type: "VALUE", value: "2" },
       { type: "RIGHT_BRACE", value: "}" }
     ]);
-    expect(tokenize("a,")).toEqual([
-      { type: "SYMBOL", value: "a" },
-      { type: "COMMA", value: "," }
-    ]);
+    expect(tokenize("a,")).toEqual([{ type: "SYMBOL", value: "a" }, { type: "COMMA", value: "," }]);
     expect(tokenize("][")).toEqual([
       { type: "RIGHT_BRACKET", value: "]" },
       { type: "LEFT_BRACKET", value: "[" }
@@ -40,11 +35,13 @@ describe("tokenizer", () => {
   });
 
   test("various operators", () => {
-    expect(tokenize(">= <= < >")).toEqual([
+    expect(tokenize(">= <= < > !== !=")).toEqual([
       { type: "OPERATOR", value: ">=" },
       { type: "OPERATOR", value: "<=" },
       { type: "OPERATOR", value: "<" },
       { type: "OPERATOR", value: ">" },
+      { type: "OPERATOR", value: "!==" },
+      { type: "OPERATOR", value: "!=" }
     ]);
   });
 
@@ -52,25 +49,17 @@ describe("tokenizer", () => {
     expect(() => tokenize("'")).toThrow("Invalid expression");
     expect(() => tokenize("'\\")).toThrow("Invalid expression");
     expect(() => tokenize("'\\'")).toThrow("Invalid expression");
-    expect(tokenize("'hello ged'")).toEqual([
-      { type: "VALUE", value: "'hello ged'" }
-    ]);
-    expect(tokenize("'hello \\'ged\\''")).toEqual([
-      { type: "VALUE", value: "'hello \\'ged\\''" }
-    ]);
+    expect(tokenize("'hello ged'")).toEqual([{ type: "VALUE", value: "'hello ged'" }]);
+    expect(tokenize("'hello \\'ged\\''")).toEqual([{ type: "VALUE", value: "'hello \\'ged\\''" }]);
 
     expect(() => tokenize('"')).toThrow("Invalid expression");
     expect(() => tokenize('"\\"')).toThrow("Invalid expression");
-    expect(tokenize('"hello ged"')).toEqual([
-      { type: "VALUE", value: '"hello ged"' }
-    ]);
+    expect(tokenize('"hello ged"')).toEqual([{ type: "VALUE", value: '"hello ged"' }]);
     expect(tokenize('"hello ged"}')).toEqual([
       { type: "VALUE", value: '"hello ged"' },
       { type: "RIGHT_BRACE", value: "}" }
     ]);
-    expect(tokenize('"hello \\"ged\\""')).toEqual([
-      { type: "VALUE", value: '"hello \\"ged\\""' }
-    ]);
+    expect(tokenize('"hello \\"ged\\""')).toEqual([{ type: "VALUE", value: '"hello \\"ged\\""' }]);
   });
 });
 
@@ -111,9 +100,7 @@ describe("expression evaluation", () => {
   test("arrays and objects", () => {
     expect(compileExpr("[{b:1}] ", {})).toBe("[{b:1}]");
     expect(compileExpr("{a: []} ", {})).toBe("{a:[]}");
-    expect(compileExpr("[{b:1, c: [1, {d: {e: 3}} ]}] ", {})).toBe(
-      "[{b:1,c:[1,{d:{e:3}}]}]"
-    );
+    expect(compileExpr("[{b:1, c: [1, {d: {e: 3}} ]}] ", {})).toBe("[{b:1,c:[1,{d:{e:3}}]}]");
   });
 
   test("dot operator", () => {
@@ -128,13 +115,9 @@ describe("expression evaluation", () => {
   });
 
   test("various binary operators", () => {
-    expect(compileExpr("color == 'black'", {})).toBe(
-      "context['color']=='black'"
-    );
+    expect(compileExpr("color == 'black'", {})).toBe("context['color']=='black'");
     expect(compileExpr("a || b", {})).toBe("context['a']||context['b']");
-    expect(compileExpr("color === 'black'", {})).toBe(
-      "context['color']==='black'"
-    );
+    expect(compileExpr("color === 'black'", {})).toBe("context['color']==='black'");
     expect(compileExpr("'li_'+item", {})).toBe("'li_'+context['item']");
     expect(compileExpr("state.val > 1", {})).toBe("context['state'].val>1");
   });
@@ -162,18 +145,14 @@ describe("expression evaluation", () => {
     expect(compileExpr("a()", {})).toBe("context['a']()");
     expect(compileExpr("a(1)", {})).toBe("context['a'](1)");
     expect(compileExpr("a(1,2)", {})).toBe("context['a'](1,2)");
-    expect(compileExpr("a(1,2,{a:[a]})", {})).toBe(
-      "context['a'](1,2,{a:[context['a']]})"
-    );
+    expect(compileExpr("a(1,2,{a:[a]})", {})).toBe("context['a'](1,2,{a:[context['a']]})");
     expect(compileExpr("'x'.toUpperCase()", {})).toBe("'x'.toUpperCase()");
-    expect(compileExpr("'x'.toUpperCase({a: 3})", {})).toBe(
-      "'x'.toUpperCase({a:3})"
+    expect(compileExpr("'x'.toUpperCase({a: 3})", {})).toBe("'x'.toUpperCase({a:3})");
+    expect(compileExpr("'x'.toUpperCase(a)", { a: { id: "_v5", expr: "" } })).toBe(
+      "'x'.toUpperCase(_v5)"
+    );
+    expect(compileExpr("'x'.toUpperCase({b: a})", { a: { id: "_v5", expr: "" } })).toBe(
+      "'x'.toUpperCase({b:_v5})"
     );
-    expect(
-      compileExpr("'x'.toUpperCase(a)", { a: { id: "_v5", expr: "" } })
-    ).toBe("'x'.toUpperCase(_v5)");
-    expect(
-      compileExpr("'x'.toUpperCase({b: a})", { a: { id: "_v5", expr: "" } })
-    ).toBe("'x'.toUpperCase({b:_v5})");
   });
 });

tests/router/__snapshots__/link.test.ts.snap

@@ -0,0 +1,22 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Link component can render simple cases 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.constructor.utils;
+    let owner = context;
+    let sibling = null;
+    var h = this.h;
+    let _1 = utils.toObj({'router-link-active':context['isActive']});
+    var _2 = context['href'];
+    let c3 = [], p3 = {key:3,attrs:{href: _2},class:_1,on:{}};
+    var vn3 = h('a', p3, c3);
+    extra.handlers['click' + 3] = extra.handlers['click' + 3] || function (e) {const fn = context['navigate'];if (fn) { fn.call(owner, e); } else { context.navigate; }};
+    p3.on['click'] = extra.handlers['click' + 3];
+    const slot4 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot4) {
+        slot4.call(this, context.__owl__.parent, Object.assign({}, extra, {parentNode: c3, vars: extra.vars, parent: owner}));
+    }
+    return vn3;
+}"
+`;

tests/router/__snapshots__/route_component.test.ts.snap

@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`RouteComponent can render simple cases 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.constructor.utils;
+    let QWeb = this.constructor;
+    let parent = context;
+    let owner = context;
+    let sibling = null;
+    let result;
+    var h = this.h;
+    if (context['routeComponent']) {
+        //COMPONENT
+        let key3 = 'key' + context['env'].router.currentRouteName;
+        let templateId2 = \`__4__\` + key3;
+        let w2 = templateId2 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[templateId2]] : false;
+        let vn5 = {};
+        result = vn5;
+        let props2 = Object.assign({}, context['env'].router.currentParams);
+        if (w2 && w2.__owl__.currentFiber && !w2.__owl__.vnode) {
+            w2.destroy();
+            w2 = false;
+        }
+        if (w2) {
+            w2.__updateProps(props2, extra.fiber, undefined, undefined, sibling);
+            let pvnode = w2.__owl__.pvnode;
+            utils.defineProxy(vn5, pvnode);
+        } else {
+            let componentKey2 = \`routeComponent\`;
+            let W2 = context.constructor.components[componentKey2] || QWeb.components[componentKey2]|| context['routeComponent'];
+            if (!W2) {throw new Error('Cannot find the definition of component \\"' + componentKey2 + '\\"')}
+            w2 = new W2(parent, props2);
+            parent.__owl__.cmap[templateId2] = w2.__owl__.id;
+            let def1 = w2.__prepare(extra.fiber, undefined, undefined, sibling);
+            let pvnode = h('dummy', {key: templateId2, hook: {insert(vn) { let nvn=w2.__mount(fiber, pvnode.elm);pvnode.elm=nvn.elm;},remove() {},destroy(vn) {w2.destroy();}}});
+            const fiber = w2.__owl__.currentFiber;
+            def1.then(function () {if (w2.__owl__.isDestroyed) {return;} const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
+            utils.defineProxy(vn5, pvnode);
+            w2.__owl__.pvnode = pvnode;
+        }
+        sibling = w2.__owl__.currentFiber || sibling;
+    }
+    return result;
+}"
+`;

tests/router/link.test.ts

@@ -0,0 +1,84 @@
+import { Component } from "../../src/component/component";
+import { Link } from "../../src/router/link";
+import { RouterEnv } from "../../src/router/router";
+import { makeTestEnv, makeTestFixture, nextTick } from "../helpers";
+import { TestRouter } from "./test_router";
+
+describe("Link component", () => {
+  let fixture: HTMLElement;
+  let env: RouterEnv;
+  let router: TestRouter | null = null;
+
+  beforeEach(() => {
+    fixture = makeTestFixture();
+    env = <RouterEnv>makeTestEnv();
+  });
+
+  afterEach(() => {
+    fixture.remove();
+    if (router) {
+      router.destroy();
+    }
+    router = null;
+  });
+
+  test("can render simple cases", async () => {
+    env.qweb.addTemplates(`
+        <templates>
+            <div t-name="App">
+                <Link to="'about'">About</Link>
+            </div>
+        </templates>
+    `);
+    class App extends Component<any, any> {
+      static components = { Link: Link };
+    }
+
+    const routes = [{ name: "about", path: "/about" }, { name: "users", path: "/users" }];
+
+    router = new TestRouter(env, routes, { mode: "history" });
+    router.navigate({ to: "users" });
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe('<div><a href="/about">About</a></div>');
+
+    expect(window.location.pathname).toBe("/users");
+    fixture.querySelector("a")!.click();
+    await nextTick();
+    expect(window.location.pathname).toBe("/about");
+    expect(fixture.innerHTML).toBe(
+      '<div><a href="/about" class="router-link-active">About</a></div>'
+    );
+
+    expect(env.qweb.templates[Link.template].fn.toString()).toMatchSnapshot();
+  });
+
+  test("do not redirect if right clicking", async () => {
+    env.qweb.addTemplates(`
+        <templates>
+            <div t-name="App">
+                <Link to="'about'">About</Link>
+            </div>
+        </templates>
+    `);
+    class App extends Component<any, any> {
+      static components = { Link: Link };
+    }
+
+    const routes = [{ name: "about", path: "/about" }, { name: "users", path: "/users" }];
+
+    router = new TestRouter(env, routes, { mode: "history" });
+    router.navigate({ to: "users" });
+    const app = new App(env);
+    await app.mount(fixture);
+
+    expect(window.location.pathname).toBe("/users");
+    var evt = new MouseEvent("click", {
+      button: 1
+    });
+
+    fixture.querySelector("a")!.dispatchEvent(evt);
+    await nextTick();
+    expect(window.location.pathname).toBe("/users");
+  });
+});

tests/router/route_component.test.ts

@@ -0,0 +1,105 @@
+import { Component } from "../../src/component/component";
+import { RouterEnv } from "../../src/router/router";
+import { RouteComponent } from "../../src/router/route_component";
+import { makeTestEnv, makeTestFixture, nextTick } from "../helpers";
+import { TestRouter } from "./test_router";
+
+describe("RouteComponent", () => {
+  let fixture: HTMLElement;
+  let env: RouterEnv;
+  let router: TestRouter | null = null;
+
+  beforeEach(() => {
+    fixture = makeTestFixture();
+    env = <RouterEnv>makeTestEnv();
+  });
+
+  afterEach(() => {
+    fixture.remove();
+    if (router) {
+      router.destroy();
+    }
+    router = null;
+  });
+
+  test("can render simple cases", async () => {
+    env.qweb.addTemplates(`
+        <templates>
+            <div t-name="App">
+                <RouteComponent />
+            </div>
+            <span t-name="About">About</span>
+            <span t-name="Users">Users</span>
+        </templates>
+    `);
+    class About extends Component<any, any> {}
+    class Users extends Component<any, any> {}
+    class App extends Component<any, any> {
+      static components = { RouteComponent };
+    }
+
+    const routes = [
+      { name: "about", path: "/about", component: About },
+      { name: "users", path: "/users", component: Users }
+    ];
+
+    router = new TestRouter(env, routes, { mode: "history" });
+    await router.navigate({ to: "about" });
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>About</span></div>");
+
+    await router.navigate({ to: "users" });
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>Users</span></div>");
+    expect(env.qweb.templates[RouteComponent.template].fn.toString()).toMatchSnapshot();
+  });
+
+  test("can render parameterized route", async () => {
+    env.qweb.addTemplates(`
+        <templates>
+            <div t-name="App">
+                <RouteComponent />
+            </div>
+            <span t-name="Book">Book <t t-esc="props.title"/></span>
+        </templates>
+    `);
+    class Book extends Component<any, any> {}
+    class App extends Component<any, any> {
+      static components = { RouteComponent };
+    }
+
+    const routes = [{ name: "book", path: "/book/{{title}}", component: Book }];
+    router = new TestRouter(env, routes, { mode: "history" });
+    await router.navigate({ to: "book", params: { title: "1984" } });
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>Book 1984</span></div>");
+  });
+
+  test("can render parameterized route with suffixes", async () => {
+    env.qweb.addTemplates(`
+        <templates>
+            <div t-name="App">
+                <RouteComponent />
+            </div>
+            <span t-name="Book">Book <t t-esc="props.title"/>|<t t-esc="incVal"/></span>
+        </templates>
+    `);
+    class Book extends Component<any, any> {
+      get incVal() {
+        return this.props.val + 1;
+      }
+    }
+    class App extends Component<any, any> {
+      static components = { RouteComponent };
+    }
+
+    const routes = [{ name: "book", path: "/book/{{title}}/{{val.number}}", component: Book }];
+    router = new TestRouter(env, routes, { mode: "history" });
+    await router.navigate({ to: "book", params: { title: "1984", val: "123" } });
+    const app = new App(env);
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>Book 1984|124</span></div>");
+  });
+});

tests/router/router.test.ts

@@ -0,0 +1,258 @@
+import { Destination, RouterEnv, Route } from "../../src/router/router";
+import { makeTestEnv, nextTick } from "../helpers";
+import { TestRouter } from "./test_router";
+
+let env: RouterEnv;
+let router: TestRouter | null = null;
+
+beforeEach(() => {
+  env = <RouterEnv>makeTestEnv();
+  window.history.pushState({}, "/", "/");
+});
+
+afterEach(() => {
+  if (router) {
+    router.destroy();
+  }
+  router = null;
+});
+
+describe("router miscellaneous", () => {
+  test("validate routes shape", () => {
+    expect(() => {
+      router = new TestRouter(env, [
+        { name: "someroute", path: "/some/path", redirect: { abc: "hey" } as Destination }
+      ]);
+    }).toThrow(`Invalid destination: {"abc":"hey"}`);
+  });
+
+  test("navigate to same route but with different params should trigger update", async () => {
+    router = new TestRouter(env, [{ name: "users", path: "/users/{{id}}" }]);
+    env.qweb.forceUpdate = jest.fn();
+    await router.navigate({ to: "users", params: { id: 3 } });
+    expect(window.location.pathname).toBe("/users/3");
+    expect(env.qweb.forceUpdate).toHaveBeenCalledTimes(1);
+
+    await router.navigate({ to: "users", params: { id: 5 } });
+    expect(window.location.pathname).toBe("/users/5");
+    expect(env.qweb.forceUpdate).toHaveBeenCalledTimes(2);
+  });
+
+  test("changing url to same route but with different params should trigger update (hash mode)", async () => {
+    env.qweb.forceUpdate = jest.fn();
+    router = new TestRouter(env, [{ name: "users", path: "/users/{{id}}" }], { mode: "hash" });
+    await router.start();
+    await router.navigate({ to: "users", params: { id: 3 } });
+    expect(window.location.hash).toBe("#/users/3");
+    expect(env.qweb.forceUpdate).toHaveBeenCalledTimes(1);
+
+    window.location.hash = "/users/5";
+    window.dispatchEvent(new Event("hashchange"));
+    await nextTick();
+    expect(window.location.hash).toBe("#/users/5");
+    expect(env.qweb.forceUpdate).toHaveBeenCalledTimes(2);
+  });
+});
+
+describe("routeToPath", () => {
+  test("simple non parameterized path", () => {
+    router = new TestRouter(env, []);
+    expect(router["routeToPath"]({ path: "/abc" } as Route, {})).toBe("/abc");
+    expect(router["routeToPath"]({ path: "/abc/def" } as Route, {})).toBe("/abc/def");
+    expect(router["routeToPath"]({ path: "/abc" } as Route, { val: 12 })).toBe("/abc");
+  });
+
+  test("simple parameterized path", () => {
+    router = new TestRouter(env, []);
+    expect(router["routeToPath"]({ path: "/abc/{{def}}" } as Route, { def: 34 })).toBe("/abc/34");
+  });
+
+  test("simple non parameterized path, mode = hash", () => {
+    router = new TestRouter(env, [], { mode: "hash" });
+    expect(router["routeToPath"]({ path: "/abc" } as Route, {})).toBe("#/abc");
+    expect(router["routeToPath"]({ path: "/abc/def" } as Route, {})).toBe("#/abc/def");
+    expect(router["routeToPath"]({ path: "/abc" } as Route, { val: 12 })).toBe("#/abc");
+  });
+
+  test("simple parameterized path, mode=hash", () => {
+    router = new TestRouter(env, [], { mode: "hash" });
+    expect(router["routeToPath"]({ path: "/abc/{{def}}" } as Route, { def: 34 })).toBe("#/abc/34");
+  });
+});
+
+describe("destToPath", () => {
+  test("validate destination shape", () => {
+    router = new TestRouter(env, [{ name: "someroute", path: "/some/path" }]);
+    expect(() => {
+      router!.destToPath({ abc: 123 } as Destination);
+    }).toThrow('Invalid destination: {"abc":123}');
+
+    expect(() => {
+      router!.destToPath({ to: "someroute" } as Destination);
+    }).not.toThrow();
+
+    expect(() => {
+      router!.destToPath({ path: "/someroute", to: "otherroute" } as Destination);
+    }).toThrow();
+  });
+});
+
+describe("getRouteParams", () => {
+  test("properly match simple routes", () => {
+    router = new TestRouter(env, []);
+    // simple route
+    expect(router["getRouteParams"]({ path: "/home" } as Route, "/home")).toEqual({});
+
+    // no match
+    expect(router["getRouteParams"]({ path: "/home" } as Route, "/otherpath")).toEqual(false);
+
+    // fallback route
+    expect(router["getRouteParams"]({ path: "*" } as Route, "somepath")).toEqual({});
+  });
+
+  test("properly match simple routes, mode hash", () => {
+    router = new TestRouter(env, [], { mode: "hash" });
+    // simple route
+    expect(router["getRouteParams"]({ path: "/home" } as Route, "#/home")).toEqual({});
+
+    // no match
+    expect(router["getRouteParams"]({ path: "/home" } as Route, "#/otherpath")).toEqual(false);
+
+    // fallback route
+    expect(router["getRouteParams"]({ path: "*" } as Route, "#/somepath")).toEqual({});
+  });
+
+  test("match some parameterized routes", () => {
+    router = new TestRouter(env, []);
+    expect(router["getRouteParams"]({ path: "/invoices/{{id}}" } as Route, "/invoices/3")).toEqual({
+      id: "3"
+    });
+  });
+
+  test("match some parameterized routes, mode hash", () => {
+    router = new TestRouter(env, [], { mode: "hash" });
+    expect(router["getRouteParams"]({ path: "/invoices/{{id}}" } as Route, "#/invoices/3")).toEqual(
+      {
+        id: "3"
+      }
+    );
+  });
+
+  test("can convert to number if needed", () => {
+    router = new TestRouter(env, []);
+    expect(
+      router["getRouteParams"]({ path: "/invoices/{{id.number}}" } as Route, "/invoices/3")
+    ).toEqual({
+      id: 3
+    });
+  });
+
+  test("can convert to number if needed, mode: hash", () => {
+    router = new TestRouter(env, [], { mode: "hash" });
+    expect(
+      router["getRouteParams"]({ path: "/invoices/{{id.number}}" } as Route, "#/invoices/3")
+    ).toEqual({
+      id: 3
+    });
+  });
+});
+
+describe("redirect", () => {
+  test("can redirect to other route", async () => {
+    router = new TestRouter(env, [
+      { name: "routea", path: "/some/path" },
+      { name: "routeb", path: "/some/other/path", redirect: { to: "routea" } }
+    ]);
+
+    await router.start();
+    expect(window.location.pathname).toBe("/");
+    await router.navigate({ to: "routeb" });
+    expect(window.location.pathname).toBe("/some/path");
+    expect(router.currentRouteName).toBe("routea");
+  });
+
+  test("can redirect to other path", async () => {
+    router = new TestRouter(env, [
+      { name: "routea", path: "/some/path" },
+      { name: "routeb", path: "/some/other/path", redirect: { path: "/some/path" } }
+    ]);
+    router.navigate = jest.fn(router.navigate);
+
+    await router.start();
+    await router.navigate({ to: "routeb" });
+
+    // once because we ask for it, once because it is redirected
+    // expect(router.navigate).toBeCalledTimes(2);
+    expect(window.location.pathname).toBe("/some/path");
+    expect(router.currentRouteName).toBe("routea");
+  });
+});
+
+describe("beforeRouteEnter", () => {
+  test("navigation guard is called and properly handle return true", async () => {
+    expect(window.location.pathname).not.toBe("/some/path");
+    const guard = jest.fn(() => true);
+    router = new TestRouter(env, [{ name: "route", path: "/some/path", beforeRouteEnter: guard }]);
+
+    await router.start();
+    await router.navigate({ to: "route" });
+    expect(guard).toBeCalledTimes(1);
+    expect(window.location.pathname).toBe("/some/path");
+    expect(router.currentRouteName).toBe("route");
+  });
+
+  test("navigation is cancelled if guard return false", async () => {
+    expect(window.location.pathname).toBe("/");
+    const guard = jest.fn(() => false);
+    router = new TestRouter(env, [
+      { name: "routea", path: "/some/patha" },
+      { name: "routeb", path: "/some/pathb", beforeRouteEnter: guard }
+    ]);
+
+    await router.start();
+    await router.navigate({ to: "routea" });
+    expect(window.location.pathname).toBe("/some/patha");
+    const result = await router.navigate({ to: "routeb" });
+    expect(result).toBe(false);
+    expect(guard).toBeCalledTimes(1);
+    expect(window.location.pathname).toBe("/some/patha");
+    expect(router.currentRouteName).toBe("routea");
+  });
+
+  test("navigation is redirected if guard decides so", async () => {
+    expect(window.location.pathname).toBe("/");
+    const guard = jest.fn(() => {
+      return { to: "routec" };
+    });
+    router = new TestRouter(env, [
+      { name: "routea", path: "/some/patha" },
+      { name: "routeb", path: "/some/pathb", beforeRouteEnter: guard },
+      { name: "routec", path: "/some/pathc" }
+    ]);
+
+    await router.start();
+    const result = await router.navigate({ to: "routea" });
+    expect(result).toBe(true);
+    expect(window.location.pathname).toBe("/some/patha");
+    await router.navigate({ to: "routeb" });
+    expect(guard).toBeCalledTimes(1);
+    expect(window.location.pathname).toBe("/some/pathc");
+    expect(router.currentRouteName).toBe("routec");
+  });
+
+  test("navigation is initially redirected if guard decides so", async () => {
+    expect(window.location.pathname).toBe("/");
+    const guard = jest.fn(() => {
+      return { to: "otherroute" };
+    });
+    router = new TestRouter(env, [
+      { name: "landing", path: "/", beforeRouteEnter: guard },
+      { name: "otherroute", path: "/some/other/route" }
+    ]);
+
+    expect(window.location.pathname).toBe("/");
+
+    await router.start();
+    expect(window.location.pathname).toBe("/some/other/route");
+  });
+});

tests/router/test_router.ts

@@ -0,0 +1,15 @@
+import { Router } from "../../src/router/router";
+import { QWeb } from "../../src/qweb/index";
+
+export class TestRouter extends Router {
+  destroy() {
+    window.removeEventListener("popstate", (this as any)._listener);
+
+    // remove component defined inroutes
+    for (let key in QWeb.components) {
+      if (key.startsWith("__component__")) {
+        delete QWeb.components[key];
+      }
+    }
+  }
+}

tests/store_hooks.test.ts

@@ -0,0 +1,990 @@
+import { Component, Env } from "../src/component/component";
+import { Store, useStore, useDispatch, useGetters } from "../src/store";
+import { useState } from "../src/hooks";
+import { xml } from "../src/tags";
+import { shallowEqual } from "../src/utils";
+import { makeTestEnv, makeTestFixture, nextTick, makeDeferred } from "./helpers";
+
+describe("connecting a component to store", () => {
+  let fixture: HTMLElement;
+  let env: Env;
+
+  beforeEach(() => {
+    fixture = makeTestFixture();
+    env = makeTestEnv();
+  });
+
+  afterEach(() => {
+    fixture.remove();
+  });
+
+  test("connecting a component works, with useStore", async () => {
+    let nextId = 1;
+    const state = { todos: [] };
+    const actions = {
+      addTodo({ state }, msg) {
+        state.todos.push({ msg, id: nextId++ });
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class App extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span t-foreach="todos" t-key="todo.id" t-as="todo"><t t-esc="todo.msg"/></span>
+            </div>`;
+      todos = useStore(state => state.todos);
+    }
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div></div>");
+
+    await store.dispatch("addTodo", "hello");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>hello</span></div>");
+  });
+
+  test("can use useStore twice in a component", async () => {
+    const state = { a: 1, b: 2 };
+    const actions = {
+      doSomething({ state }) {
+        state.a = 2;
+        state.b = 3;
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class App extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span t-esc="a.value"/>
+                <span t-esc="b.value"/>
+            </div>`;
+      a = useStore(state => ({ value: state.a }));
+      b = useStore(state => ({ value: state.b }));
+    }
+    App.prototype.__render = jest.fn(App.prototype.__render);
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>1</span><span>2</span></div>");
+    expect(App.prototype.__render).toBeCalledTimes(1);
+
+    await store.dispatch("doSomething");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>2</span><span>3</span></div>");
+    expect(App.prototype.__render).toBeCalledTimes(2);
+  });
+
+  test("useStore: do not re-render if not changed", async () => {
+    let nextId = 1;
+    const state = { todos: [], a: 1 };
+    const actions = {
+      addTodo({ state }, msg) {
+        state.todos.push({ msg, id: nextId++ });
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class App extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span t-foreach="todos" t-key="todo.id" t-as="todo"><t t-esc="todo.msg"/></span>
+            </div>`;
+      todos = useStore(state => state.todos);
+    }
+    App.prototype.__render = jest.fn(App.prototype.__render);
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div></div>");
+    expect(App.prototype.__render).toBeCalledTimes(1);
+
+    store.state.todos.push({ id: 3, msg: "hello" });
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>hello</span></div>");
+    expect(App.prototype.__render).toBeCalledTimes(2);
+
+    store.state.a = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>hello</span></div>");
+    expect(App.prototype.__render).toBeCalledTimes(2);
+  });
+
+  test("connecting a component with useStore returning number", async () => {
+    let nextId = 1;
+    const state = { todos: [] };
+    const actions = {
+      addTodo({ state }, msg) {
+        state.todos.push({ msg, id: nextId++ });
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class App extends Component<any, any> {
+      static template = xml`<div><t t-esc="nbrTodos.value"/></div>`;
+      nbrTodos = useStore(state => ({ value: state.todos.length }));
+    }
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>0</div>");
+
+    await store.dispatch("addTodo", "hello");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>1</div>");
+  });
+
+  test("connecting a component with useStore returning number", async () => {
+    let nextId = 1;
+    const state = { todos: [], a: 1 };
+    const actions = {
+      addTodo({ state }, msg) {
+        state.todos.push({ msg, id: nextId++ });
+      },
+      incrementA({ state }) {
+        state.a++;
+      }
+    };
+    const store = new Store({ state, actions });
+    class App extends Component<any, any> {
+      static template = xml`<div><t t-esc="nbrTodos.value"/></div>`;
+      nbrTodos = useStore(state => ({ value: state.todos.length }), { isEqual: shallowEqual });
+    }
+    App.prototype.__render = jest.fn(App.prototype.__render);
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>0</div>");
+    expect(App.prototype.__render).toBeCalledTimes(1);
+
+    await store.dispatch("addTodo", "hello");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>1</div>");
+    expect(App.prototype.__render).toBeCalledTimes(2);
+
+    await store.dispatch("incrementA");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>1</div>");
+    expect(App.prototype.__render).toBeCalledTimes(2);
+  });
+
+  test("connecting a component to a local store", async () => {
+    let nextId = 1;
+    const state = { todos: [] };
+    const actions = {
+      addTodo({ state }, msg) {
+        state.todos.push({ msg, id: nextId++ });
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class App extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span t-foreach="todos" t-key="todo.id" t-as="todo"><t t-esc="todo.msg"/></span>
+            </div>`;
+      todos = useStore(state => state.todos, { store });
+    }
+
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div></div>");
+
+    await store.dispatch("addTodo", "hello");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>hello</span></div>");
+  });
+
+  test("can dispatch actions from a connected component", async () => {
+    const store = new Store({
+      state: { value: 1 },
+      actions: {
+        inc({ state }) {
+          state.value++;
+        }
+      }
+    });
+    (<any>env).store = store;
+
+    class App extends Component<any, any> {
+      static template = xml`
+          <div>
+              <button t-on-click="dispatch('inc')">Inc</button>
+              <span><t t-esc="storeState.value"/></span>
+          </div>`;
+      storeState = useStore(state => state);
+      dispatch = useDispatch();
+    }
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><button>Inc</button><span>1</span></div>");
+
+    fixture.querySelector("button")!.click();
+    await nextTick();
+
+    expect(fixture.innerHTML).toBe("<div><button>Inc</button><span>2</span></div>");
+  });
+
+  test("useStore can use props", async () => {
+    const state = { todos: [{ id: 1, text: "jupiler" }, { id: 2, text: "chimay" }] };
+    const store = new Store({ state, actions: {} });
+
+    class TodoItem extends Component<any, any> {
+      static template = xml`<span><t t-esc="todo.text"/></span>`;
+      todo = useStore((state, props) => {
+        return state.todos.find(t => t.id === props.todoId);
+      });
+    }
+
+    class App extends Component<any, any> {
+      static template = xml`<div><TodoItem todoId="state.currentId"/></div>`;
+      static components = { TodoItem };
+      state = useState({ currentId: 1 });
+    }
+
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span></div>");
+
+    app.state.currentId = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>chimay</span></div>");
+  });
+
+  test("useStore receives props as second argument", async () => {
+    const state = { todos: [{ id: 1, text: "jupiler" }] };
+    let nextId = 2;
+    const actions = {
+      addTodo({ state }, text) {
+        state.todos.push({ text, id: nextId++ });
+      }
+    };
+    const store = new Store({ state, actions });
+
+    class TodoItem extends Component<any, any> {
+      static template = xml`<span><t t-esc="todo.text"/></span>`;
+      todo = useStore((state, props) => {
+        return state.todos.find(t => t.id === props.id);
+      });
+    }
+
+    class TodoList extends Component<any, any> {
+      static template = xml`
+        <div>
+          <TodoItem t-foreach="todos" t-as="todo" id="todo.id" t-key="todo.id"/>
+        </div>`;
+      static components = { TodoItem };
+      todos = useStore(state => state.todos);
+    }
+
+    (<any>env).store = store;
+    const app = new TodoList(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span></div>");
+
+    store.dispatch("addTodo", "hoegaarden");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span><span>hoegaarden</span></div>");
+  });
+
+  test("can call useGetters to receive store getters", async () => {
+    const state = {
+      importantID: 1,
+      todos: [{ id: 1, text: "jupiler" }, { id: 2, text: "bertinchamps" }]
+    };
+    const getters = {
+      importantTodoText({ state }) {
+        return state.todos.find(todo => todo.id === state.importantID).text;
+      },
+      text({ state }, id) {
+        return state.todos.find(todo => todo.id === id).text;
+      }
+    };
+    const store = new Store({ state, getters });
+
+    class TodoItem extends Component<any, any> {
+      static template = xml`
+        <div>
+          <span><t t-esc="storeProps.activeTodoText"/></span>
+          <span><t t-esc="storeProps.importantTodoText"/></span>
+        </div>`;
+      getters = useGetters();
+      storeProps = useStore((state, props) => {
+        const todo = state.todos.find(t => t.id === props.id);
+        return {
+          activeTodoText: this.getters.text(todo.id),
+          importantTodoText: this.getters.importantTodoText()
+        };
+      });
+    }
+
+    class TodoList extends Component<any, any> {
+      static components = { TodoItem };
+      static template = xml`
+        <div>
+          <t t-foreach="todos" t-as="todo">
+            <TodoItem id="todo.id" t-key="todo.id"/>
+          </t>
+        </div>`;
+      todos = useStore(state => state.todos);
+    }
+
+    (<any>env).store = store;
+    const app = new TodoList(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>jupiler</span><span>jupiler</span></div><div><span>bertinchamps</span><span>jupiler</span></div></div>"
+    );
+  });
+
+  test("connected component is updated when props are updated", async () => {
+    class Beer extends Component<any, any> {
+      static template = xml`<span><t t-esc="beer.name"/></span>`;
+      beer = useStore((state, props) => state.beers[props.id]);
+    }
+
+    class App extends Component<any, any> {
+      static template = xml`<div><Beer id="state.beerId"/></div>`;
+      static components = { Beer };
+      state = useState({ beerId: 1 });
+    }
+
+    const state = { beers: { 1: { name: "jupiler" }, 2: { name: "kwak" } } };
+    const store = new Store({ state });
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span></div>");
+
+    app.state.beerId = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>kwak</span></div>");
+  });
+
+  test("connected component is updated when store is changed", async () => {
+    class App extends Component<any, any> {
+      static template = xml`
+        <div>
+            <span t-foreach="data.beers" t-as="beer" t-key="beer.name"><t t-esc="beer.name"/></span>
+        </div>`;
+
+      // we have here a new object
+      data = useStore(state => ({ beers: state.beers, otherKey: 1 }));
+    }
+
+    const actions = {
+      addBeer({ state }, name) {
+        state.beers.push({ name });
+      }
+    };
+
+    const state = { beers: [{ name: "jupiler" }] };
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span></div>");
+
+    store.dispatch("addBeer", "kwak");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>jupiler</span><span>kwak</span></div>");
+  });
+
+  test("connected component with undefined, null and string props", async () => {
+    class Beer extends Component<any, any> {
+      static template = xml`
+            <div t-name="Beer">
+                <span>taster:<t t-esc="data.taster"/></span>
+                <span t-if="data.selected">selected:<t t-esc="data.selected.name"/></span>
+                <span t-if="data.consumed">consumed:<t t-esc="data.consumed.name"/></span>
+            </div>`;
+      data = useStore((state, props) => ({
+        selected: state.beers[props.id],
+        consumed: state.beers[state.consumedID] || null,
+        taster: state.taster
+      }));
+    }
+
+    class App extends Component<any, any> {
+      static template = xml`<div><Beer id="state.beerId"/></div>`;
+      static components = { Beer };
+      state = useState({ beerId: 0 });
+    }
+
+    const actions = {
+      consume({ state }, beerId) {
+        state.consumedID = beerId;
+      }
+    };
+    const state = {
+      beers: {
+        1: { name: "jupiler" }
+      },
+      consumedID: null,
+      taster: "aaron"
+    };
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div><span>taster:aaron</span></div></div>");
+
+    app.state.beerId = 1;
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>selected:jupiler</span></div></div>"
+    );
+
+    store.dispatch("consume", 1);
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>selected:jupiler</span><span>consumed:jupiler</span></div></div>"
+    );
+
+    app.state.beerId = 0;
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>consumed:jupiler</span></div></div>"
+    );
+  });
+
+  test("connected component deeply reactive with undefined, null and string props", async () => {
+    class Beer extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span>taster:<t t-esc="info.taster"/></span>
+                <span t-if="info.selected">selected:<t t-esc="info.selected.name"/></span>
+                <span t-if="info.consumed">consumed:<t t-esc="info.consumed.name"/></span>
+            </div>`;
+      info = useStore(function(state, props) {
+        return {
+          selected: state.beers[props.id],
+          consumed: state.beers[state.consumedID] || null,
+          taster: state.taster
+        };
+      });
+    }
+
+    class App extends Component<any, any> {
+      static template = xml`<div><Beer id="state.beerId"/></div>`;
+      static components = { Beer };
+      state = useState({ beerId: 0 });
+    }
+
+    const actions = {
+      changeTaster({ state }, newTaster) {
+        state.taster = newTaster;
+      },
+      consume({ state }, beerId) {
+        state.consumedID = beerId;
+      },
+      renameBeer({ state }, { beerId, name }) {
+        state.beers[beerId].name = name;
+      }
+    };
+    const state = {
+      beers: {
+        1: { name: "jupiler" }
+      },
+      consumedID: null,
+      taster: "aaron"
+    };
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div><span>taster:aaron</span></div></div>");
+
+    app.state.beerId = 1;
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>selected:jupiler</span></div></div>"
+    );
+
+    store.dispatch("renameBeer", { beerId: 1, name: "kwak" });
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>selected:kwak</span></div></div>"
+    );
+
+    store.dispatch("consume", 1);
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>selected:kwak</span><span>consumed:kwak</span></div></div>"
+    );
+
+    app.state.beerId = 0;
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>consumed:kwak</span></div></div>"
+    );
+
+    store.dispatch("renameBeer", { beerId: 1, name: "jupiler" });
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:aaron</span><span>consumed:jupiler</span></div></div>"
+    );
+
+    store.dispatch("changeTaster", "matthieu");
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><span>taster:matthieu</span><span>consumed:jupiler</span></div></div>"
+    );
+  });
+
+  test("correct update order when parent/children are connected", async () => {
+    const steps: string[] = [];
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="state.msg"/></span>`;
+
+      state = useStore((state, props) => {
+        steps.push("child");
+        return { msg: state.msg[props.key] };
+      });
+    }
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child key="state.current"/></div>`;
+      static components = { Child };
+
+      state = useStore(state => {
+        steps.push("parent");
+        return {
+          current: state.current,
+          isvisible: state.isvisible
+        };
+      });
+    }
+
+    const state = { current: "a", msg: { a: "a", b: "b" } };
+    const actions = {
+      setCurrent({ state }, c) {
+        state.current = c;
+      }
+    };
+
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new Parent(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>a</span></div>");
+    expect(steps).toEqual(["parent", "child"]);
+
+    store.dispatch("setCurrent", "b");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>b</span></div>");
+    expect(steps).toEqual(["parent", "child", "parent", "child"]);
+  });
+
+  test("correct update order when parent/children are connected, part 2", async () => {
+    const steps: string[] = [];
+    let def = makeDeferred();
+    def.resolve();
+
+    class Child extends Component<any, any> {
+      static template = xml`<span><t t-esc="state.msg"/></span>`;
+      state = useStore((s, props) => {
+        steps.push("child");
+        return { msg: s.messages[props.someId] };
+      });
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`
+            <div>
+                <Child t-if="state.flag" someId="state.someId"/>
+            </div>`;
+      static components = { Child };
+      state = useStore(s => {
+        steps.push("parent");
+        return { flag: s.flag, someId: s.someId };
+      });
+
+      async render(force) {
+        await def;
+        return super.render(force);
+      }
+    }
+
+    const state = { someId: 1, flag: true, messages: { 1: "abc" } };
+    const actions = {
+      setFlagToFalse({ state }) {
+        state.flag = false;
+      }
+    };
+
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new Parent(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><span>abc</span></div>");
+    expect(steps).toEqual(["parent", "child"]);
+
+    def = makeDeferred();
+    store.dispatch("setFlagToFalse");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><span>abc</span></div>");
+    expect(steps).toEqual(["parent", "child", "parent"]);
+
+    def.resolve();
+    await nextTick();
+    expect(steps).toEqual(["parent", "child", "parent"]);
+    expect(fixture.innerHTML).toBe("<div></div>");
+  });
+
+  test("connected parent/children: no double rendering", async () => {
+    let steps: string[] = [];
+    const actions = {
+      editTodo({ state }) {
+        state.todos[1].title = "abc";
+      }
+    };
+    const todos = { 1: { id: 1, title: "kikoou" } };
+    const state = {
+      todos
+    };
+    const store = new Store({
+      state,
+      actions
+    });
+
+    class TodoItem extends Component<any, any> {
+      static template = xml`
+            <div class="todo">
+                <t t-esc="state.todo.title"/>
+                <button class="destroy" t-on-click="editTodo">x</button>
+            </div>`;
+      state = useStore((state, props) => {
+        steps.push("item:usestore");
+        return {
+          todo: state.todos[props.id]
+        };
+      });
+
+      editTodo() {
+        this.env.store.dispatch("editTodo");
+      }
+      __render(f) {
+        steps.push("item:render");
+        return super.__render(f);
+      }
+    }
+    class TodoApp extends Component<any, any> {
+      static template = xml`
+            <div class="todoapp">
+                <t t-foreach="Object.values(state.todos)" t-as="todo">
+                    <TodoItem t-key="todo.id" id="todo.id"/>
+                </t>
+            </div>`;
+      static components = { TodoItem };
+      state = useStore(state => {
+        steps.push("app:usestore");
+        return { todos: state.todos };
+      });
+      __render(f) {
+        steps.push("app:render");
+        return super.__render(f);
+      }
+    }
+
+    (<any>env).store = store;
+    const app = new TodoApp(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe(
+      '<div class="todoapp"><div class="todo">kikoou<button class="destroy">x</button></div></div>'
+    );
+
+    expect(steps).toEqual(["app:usestore", "app:render", "item:usestore", "item:render"]);
+    steps = [];
+    fixture.querySelector("button")!.click();
+    await nextTick();
+    expect(steps).toEqual(["app:usestore", "app:render", "item:usestore", "item:render"]);
+    expect(fixture.innerHTML).toBe(
+      '<div class="todoapp"><div class="todo">abc<button class="destroy">x</button></div></div>'
+    );
+  });
+
+  test("connected parent/children: no rendering if child is destroyed", async () => {
+    let steps: string[] = [];
+    const actions = {
+      removeTodo({ state }) {
+        delete state.todos[1];
+      }
+    };
+    const todos = { 1: { id: 1, title: "kikoou" } };
+    const state = {
+      todos
+    };
+    const store = new Store({
+      state,
+      actions
+    });
+
+    class TodoItem extends Component<any, any> {
+      static template = xml`
+            <div class="todo">
+                <t t-esc="state.todo.title"/>
+                <button class="destroy" t-on-click="removeTodo">x</button>
+            </div>`;
+      state = useStore((state, props) => {
+        steps.push("item:usestore");
+        return {
+          todo: state.todos[props.id]
+        };
+      });
+
+      removeTodo() {
+        this.env.store.dispatch("removeTodo");
+      }
+      __render(f) {
+        steps.push("item:render");
+        return super.__render(f);
+      }
+    }
+
+    class TodoApp extends Component<any, any> {
+      static template = xml`
+            <div class="todoapp">
+                <t t-foreach="Object.values(state.todos)" t-as="todo">
+                    <TodoItem t-key="todo.id" id="todo.id"/>
+                </t>
+            </div>`;
+      static components = { TodoItem };
+      state = useStore(state => {
+        steps.push("app:usestore");
+        return { todos: state.todos };
+      });
+      __render(f) {
+        steps.push("app:render");
+        return super.__render(f);
+      }
+    }
+
+    (<any>env).store = store;
+    const app = new TodoApp(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe(
+      '<div class="todoapp"><div class="todo">kikoou<button class="destroy">x</button></div></div>'
+    );
+
+    expect(steps).toEqual(["app:usestore", "app:render", "item:usestore", "item:render"]);
+
+    fixture.querySelector("button")!.click();
+    await nextTick();
+    expect(steps).toEqual([
+      "app:usestore",
+      "app:render",
+      "item:usestore",
+      "item:render",
+      "app:usestore",
+      "app:render"
+    ]);
+    expect(fixture.innerHTML).toBe('<div class="todoapp"></div>');
+  });
+
+  test("connected component willpatch/patch hooks are called on store updates", async () => {
+    const steps: string[] = [];
+
+    class App extends Component<any, any> {
+      static template = xml`<div><t t-esc="store.msg"/></div>`;
+      store = useStore(s => ({ msg: s.msg }));
+
+      willPatch() {
+        steps.push("willpatch");
+      }
+      patched() {
+        steps.push("patched");
+      }
+    }
+
+    const state = { msg: "a" };
+    const actions = {
+      setMsg({ state }, c) {
+        state.msg = c;
+      }
+    };
+
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>a</div>");
+
+    store.dispatch("setMsg", "b");
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>b</div>");
+    expect(steps).toEqual(["willpatch", "patched"]);
+  });
+
+  test("connected child components stop listening to store when destroyed", async () => {
+    let steps: any = [];
+
+    class Child extends Component<any, any> {
+      static template = xml`<div><t t-esc="store.val"/></div>`;
+      store = useStore(s => s);
+    }
+
+    class Parent extends Component<any, any> {
+      static template = xml`<div><Child t-if="state.child" /></div>`;
+      static components = { Child };
+      state = useState({ child: true });
+    }
+
+    class TestStore extends Store {
+      on(eventType, owner, callback) {
+        steps.push(`on:${eventType}`);
+        super.on(eventType, owner, callback);
+      }
+      off(eventType, owner) {
+        steps.push(`off:${eventType}`);
+        super.off(eventType, owner);
+      }
+    }
+    const store = new TestStore({ state: { val: 1 } });
+    (<any>env).store = store;
+    const parent = new Parent(env);
+
+    await parent.mount(fixture);
+    expect(steps).toEqual(["on:update"]);
+    expect(fixture.innerHTML).toBe("<div><div>1</div></div>");
+
+    parent.state.child = false;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div></div>");
+    expect(steps).toEqual(["on:update", "off:update"]);
+  });
+
+  test("dispatch an action", async () => {
+    class App extends Component<any, any> {
+      static template = xml`<div><t t-esc="store.counter"/></div>`;
+      store = useStore(state => state);
+      dispatch = useDispatch();
+    }
+
+    const state = {
+      counter: 0
+    };
+
+    const actions = {
+      inc({ state }) {
+        return ++state.counter;
+      }
+    };
+
+    const store = new Store({ state, actions });
+    (<any>env).store = store;
+    const app = new App(env);
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div>0</div>");
+
+    const res = app.dispatch("inc");
+    expect(res).toBe(1);
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div>1</div>");
+  });
+});
+
+describe("various scenarios", () => {
+  let fixture: HTMLElement;
+  let env: Env;
+
+  beforeEach(() => {
+    fixture = makeTestFixture();
+    env = makeTestEnv();
+  });
+
+  afterEach(() => {
+    fixture.remove();
+  });
+
+  test("scenarios with async store updates and some components events", async () => {
+    const actions = {
+      async deleteAttachment({ state }) {
+        await Promise.resolve();
+        delete state.attachments[100];
+        state.messages[10].attachmentIds = [];
+      }
+    };
+    const state = {
+      attachments: {
+        100: {
+          id: 100,
+          name: "text.txt"
+        }
+      },
+      messages: {
+        10: {
+          attachmentIds: [100],
+          id: 10
+        }
+      }
+    };
+    const store = new Store({ actions, state });
+
+    class Attachment extends Component<any, any> {
+      static template = xml`
+            <div>
+                <span>Attachment <t t-esc="props.id"/></span>
+                <span>Name: <t t-esc="attachment.name"/></span>
+            </div>`;
+
+      attachment = useStore((state, props) => ({ name: state.attachments[props.id].name }));
+    }
+
+    class Message extends Component<any, any> {
+      static template = xml`
+            <div>
+                <button t-on-click="doStuff">Do stuff</button>
+                <Attachment t-foreach="store.attachmentIds" t-key="attachmentId" t-as="attachmentId" id="attachmentId"/>
+            </div>`;
+
+      store = useStore(state => ({ attachmentIds: state.messages[10].attachmentIds }));
+      static components = { Attachment };
+      state = { isAttachmentDeleted: false };
+      dispatch = useDispatch();
+      doStuff() {
+        this.dispatch("deleteAttachment", 100);
+        this.state.isAttachmentDeleted = true;
+      }
+    }
+
+    (<any>env).store = store;
+    const message = new Message(env);
+    await message.mount(fixture);
+
+    expect(fixture.innerHTML).toMatchSnapshot();
+
+    fixture.querySelector("button")!.click();
+    await nextTick();
+    expect(fixture.innerHTML).toMatchSnapshot();
+  });
+});

tests/vdom.test.ts

@@ -1,4 +1,6 @@
-import { h, patch, init } from "../src/vdom";
+import { h, patch } from "../src/vdom";
+import { htmlToVDOM } from "../src/vdom/html_to_vdom";
+import { init, addNS } from "../src/vdom/vdom";
 
 function map(list, fn) {
   var ret: any[] = [];
@@ -59,9 +61,7 @@ describe("attributes", function() {
   test("are set correctly when namespaced", function() {
     const vnode1 = h("div", { attrs: { "xlink:href": "#foo" } });
     elm = patch(vnode0, vnode1).elm;
-    expect(elm.getAttributeNS("http://www.w3.org/1999/xlink", "href")).toBe(
-      "#foo"
-    );
+    expect(elm.getAttributeNS("http://www.w3.org/1999/xlink", "href")).toBe("#foo");
   });
 
   test("should not touch class nor id fields", function() {
@@ -185,20 +185,6 @@ describe("snabbdom", function() {
       expect(elm.tagName).toBe("DIV");
     });
 
-    test("has different tag and id", function() {
-      let elm: any = document.createElement("div");
-      vnode0.appendChild(elm);
-      const vnode1 = h("span#id");
-      elm = patch(elm, vnode1).elm;
-      expect(elm.tagName).toBe("SPAN");
-      expect(elm.id).toBe("id");
-    });
-
-    test("has id", function() {
-      elm = patch(vnode0, h("div", [h("div#unique")])).elm;
-      expect(elm.firstChild.id).toBe("unique");
-    });
-
     test("has correct namespace", function() {
       const SVGNamespace = "http://www.w3.org/2000/svg";
       const XHTMLNamespace = "http://www.w3.org/1999/xhtml";
@@ -207,37 +193,15 @@ describe("snabbdom", function() {
       expect(elm.firstChild.namespaceURI).toBe(SVGNamespace);
 
       // verify that svg tag automatically gets svg namespace
-      elm = patch(
-        vnode0,
-        h("svg", [
-          h("foreignObject", [h("div", ["I am HTML embedded in SVG"])])
-        ])
-      ).elm;
+      const vnode = h("svg", [h("foreignObject", [h("div", ["I am HTML embedded in SVG"])])]);
+      // need to add namespace manually. it is usually done by the template
+      // compiler
+      addNS(vnode.data, (vnode as any).children, vnode.sel);
+
+      elm = patch(vnode0, vnode).elm;
       expect(elm.namespaceURI).toBe(SVGNamespace);
       expect(elm.firstChild.namespaceURI).toBe(SVGNamespace);
       expect(elm.firstChild.firstChild.namespaceURI).toBe(XHTMLNamespace);
-
-      // verify that svg tag with extra selectors gets svg namespace
-      elm = patch(vnode0, h("svg#some-id")).elm;
-      expect(elm.namespaceURI).toBe(SVGNamespace);
-
-      // verify that non-svg tag beginning with 'svg' does NOT get namespace
-      elm = patch(vnode0, h("svg-custom-el")).elm;
-      expect(elm.namespaceURI).not.toBe(SVGNamespace);
-    });
-
-    test("receives classes in selector", function() {
-      elm = patch(vnode0, h("div", [h("i.am.a.class")])).elm;
-      expect(elm.firstChild.classList.contains("am")).toBeTruthy();
-      expect(elm.firstChild.classList.contains("a")).toBeTruthy();
-      expect(elm.firstChild.classList.contains("class")).toBeTruthy();
-    });
-
-    test("receives classes in selector when namespaced", function() {
-      elm = patch(vnode0, h("svg", [h("g.am.a.class.too")])).elm;
-      expect(elm.firstChild.classList.contains("am")).toBeTruthy();
-      expect(elm.firstChild.classList.contains("a")).toBeTruthy();
-      expect(elm.firstChild.classList.contains("class")).toBeTruthy();
     });
 
     test("can create elements with text content", function() {
@@ -276,26 +240,6 @@ describe("snabbdom", function() {
   });
 
   describe("patching an element", function() {
-    test("changes the elements classes", function() {
-      const vnode1 = h("i.i.am.horse");
-      const vnode2 = h("i.i.am");
-      patch(vnode0, vnode1);
-      elm = patch(vnode1, vnode2).elm;
-      expect(elm.classList.contains("i")).toBeTruthy();
-      expect(elm.classList.contains("am")).toBeTruthy();
-      expect(!elm.classList.contains("horse")).toBeTruthy();
-    });
-
-    test("removes missing classes", function() {
-      const vnode1 = h("i.i.am.horse");
-      const vnode2 = h("i.i.am");
-      patch(vnode0, vnode1);
-      elm = patch(vnode1, vnode2).elm;
-      expect(elm.classList.contains("i")).toBeTruthy();
-      expect(elm.classList.contains("am")).toBeTruthy();
-      expect(!elm.classList.contains("horse")).toBeTruthy();
-    });
-
     test("changes an elements props", function() {
       const vnode1 = h("a", { props: { src: "http://other/" } });
       const vnode2 = h("a", { props: { src: "http://localhost/" } });
@@ -352,13 +296,7 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(2);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("add elements in the middle", function() {
@@ -368,13 +306,7 @@ describe("snabbdom", function() {
         expect(elm.children.length).toBe(4);
         expect(elm.children.length).toBe(4);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("add elements at beginning and end", function() {
@@ -383,13 +315,7 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(3);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("adds children to parent with no children", function() {
@@ -588,35 +514,19 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(6);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "4",
-          "3",
-          "2",
-          "1",
-          "5",
-          "0"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["4", "3", "2", "1", "5", "0"]);
       });
 
       test("supports null/undefined children", function() {
         const vnode1 = h("i", [0, 1, 2, 3, 4, 5].map(spanNum));
         const vnode2 = h(
           "i",
-          [null, 2, undefined, null, 1, 0, null, 5, 4, null, 3, undefined].map(
-            spanNum
-          )
+          [null, 2, undefined, null, 1, 0, null, 5, 4, null, 3, undefined].map(spanNum)
         );
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(6);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "2",
-          "1",
-          "0",
-          "5",
-          "4",
-          "3"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["2", "1", "0", "5", "4", "3"]);
       });
 
       test("supports all null/undefined children", function() {
@@ -627,14 +537,7 @@ describe("snabbdom", function() {
         elm = patch(vnode1, vnode2).elm;
         expect(elm.children.length).toBe(0);
         elm = patch(vnode2, vnode3).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "5",
-          "4",
-          "3",
-          "2",
-          "1",
-          "0"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["5", "4", "3", "2", "1", "0"]);
       });
     });
   });
@@ -714,18 +617,10 @@ describe("snabbdom", function() {
     });
 
     test("removes elements", function() {
-      const vnode1 = h("div", [
-        h("span", "One"),
-        h("span", "Two"),
-        h("span", "Three")
-      ]);
+      const vnode1 = h("div", [h("span", "One"), h("span", "Two"), h("span", "Three")]);
       const vnode2 = h("div", [h("span", "One"), h("span", "Three")]);
       elm = patch(vnode0, vnode1).elm;
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "One",
-        "Two",
-        "Three"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Two", "Three"]);
       elm = patch(vnode1, vnode2).elm;
       expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Three"]);
     });
@@ -760,49 +655,19 @@ describe("snabbdom", function() {
     });
 
     test("reorders elements", function() {
-      const vnode1 = h("div", [
-        h("span", "One"),
-        h("div", "Two"),
-        h("b", "Three")
-      ]);
-      const vnode2 = h("div", [
-        h("b", "Three"),
-        h("span", "One"),
-        h("div", "Two")
-      ]);
+      const vnode1 = h("div", [h("span", "One"), h("div", "Two"), h("b", "Three")]);
+      const vnode2 = h("div", [h("b", "Three"), h("span", "One"), h("div", "Two")]);
       elm = patch(vnode0, vnode1).elm;
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "One",
-        "Two",
-        "Three"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Two", "Three"]);
       elm = patch(vnode1, vnode2).elm;
       expect(map(elm.children, c => c.tagName)).toEqual(["B", "SPAN", "DIV"]);
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "Three",
-        "One",
-        "Two"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["Three", "One", "Two"]);
     });
 
     test("supports null/undefined children", function() {
       const vnode1 = h("i", [null, h("i", "1"), h("i", "2"), null]);
-      const vnode2 = h("i", [
-        h("i", "2"),
-        undefined,
-        undefined,
-        h("i", "1"),
-        undefined
-      ]);
-      const vnode3 = h("i", [
-        null,
-        h("i", "1"),
-        undefined,
-        null,
-        h("i", "2"),
-        undefined,
-        null
-      ]);
+      const vnode2 = h("i", [h("i", "2"), undefined, undefined, h("i", "1"), undefined]);
+      const vnode3 = h("i", [null, h("i", "1"), undefined, null, h("i", "2"), undefined, null]);
       elm = patch(vnode0, vnode1).elm;
       expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2"]);
       elm = patch(vnode1, vnode2).elm;
@@ -835,10 +700,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { create: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ]),
+          h("div", { hook: { create: cb } }, [h("span", "Child 1"), h("span", "Child 2")]),
           h("span", "Can't touch me")
         ]);
         patch(vnode0, vnode1);
@@ -855,10 +717,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { insert: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ]),
+          h("div", { hook: { insert: cb } }, [h("span", "Child 1"), h("span", "Child 2")]),
           h("span", "Can touch me")
         ]);
         patch(vnode0, vnode1);
@@ -874,17 +733,11 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { prepatch: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { prepatch: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { prepatch: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { prepatch: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -965,10 +818,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { remove: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { remove: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div", [h("span", "First sibling")]);
         patch(vnode0, vnode1);
@@ -981,9 +831,7 @@ describe("snabbdom", function() {
         function cb(vnode) {
           calls++;
         }
-        const vnode1 = h("div", [
-          h("div", { hook: { destroy: cb } }, [h("span", "Child 1")])
-        ]);
+        const vnode1 = h("div", [h("div", { hook: { destroy: cb } }, [h("span", "Child 1")])]);
         const vnode2 = h("div", "Text node");
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1053,10 +901,7 @@ describe("snabbdom", function() {
           result.push(vnode);
           rm();
         }
-        const vnode1 = h("div", { hook: { remove: cb } }, [
-          h("b", "Child 1"),
-          h("i", "Child 2")
-        ]);
+        const vnode1 = h("div", { hook: { remove: cb } }, [h("b", "Child 1"), h("i", "Child 2")]);
         const vnode2 = h("span", [h("b", "Child 1"), h("i", "Child 2")]);
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1091,10 +936,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", [
-            h("span", { hook: { destroy: cb } }, "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", [h("span", { hook: { destroy: cb } }, "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div");
         patch(vnode0, vnode1);
@@ -1150,11 +992,7 @@ describe("snabbdom", function() {
             }
           }
         ]);
-        const vnode1 = h("div", [
-          h("span", "First child"),
-          "",
-          h("span", "Third child")
-        ]);
+        const vnode1 = h("div", [h("span", "First child"), "", h("span", "Third child")]);
         const vnode2 = h("div");
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1196,10 +1034,7 @@ describe("snabbdom", function() {
       function cb(vnode) {
         result.push(vnode);
       }
-      const vnode1 = h("div", [
-        h("span", { hook: { update: cb } }, "Hello"),
-        h("span", "there")
-      ]);
+      const vnode1 = h("div", [h("span", { hook: { update: cb } }, "Hello"), h("span", "there")]);
       patch(vnode0, vnode1);
       patch(vnode1, vnode1);
       expect(result).toHaveLength(0);
@@ -1222,3 +1057,52 @@ describe("snabbdom", function() {
     });
   });
 });
+
+//------------------------------------------------------------------------------
+// Html to vdom
+//------------------------------------------------------------------------------
+describe("html to vdom", function() {
+  let elm, vnode0;
+  beforeEach(function() {
+    elm = document.createElement("div");
+    vnode0 = elm;
+  });
+
+  test("empty strings return empty list", function() {
+    expect(htmlToVDOM("")).toEqual([]);
+  });
+
+  test("just text", function() {
+    const nodeList = htmlToVDOM("simple text");
+    expect(nodeList).toHaveLength(1);
+    expect(nodeList[0]).toEqual({ text: "simple text" });
+  });
+
+  test("empty tag", function() {
+    const nodeList = htmlToVDOM("<span></span>");
+    expect(nodeList).toHaveLength(1);
+    elm = patch(vnode0, nodeList[0]).elm;
+    expect(elm.outerHTML).toEqual("<span></span>");
+  });
+
+  test("tag with text", function() {
+    const nodeList = htmlToVDOM("<span>abc</span>");
+    expect(nodeList).toHaveLength(1);
+    elm = patch(vnode0, nodeList[0]).elm;
+    expect(elm.outerHTML).toEqual("<span>abc</span>");
+  });
+
+  test("tag with attribute", function() {
+    const nodeList = htmlToVDOM(`<span a="1" b="2">abc</span>`);
+    expect(nodeList).toHaveLength(1);
+    elm = patch(vnode0, nodeList[0]).elm;
+    expect(elm.outerHTML).toEqual(`<span a="1" b="2">abc</span>`);
+  });
+
+  test("misc", function() {
+    const nodeList = htmlToVDOM(`<span a="1" b="2">abc<div>1</div></span>`);
+    expect(nodeList).toHaveLength(1);
+    elm = patch(vnode0, nodeList[0]).elm;
+    expect(elm.outerHTML).toEqual(`<span a="1" b="2">abc<div>1</div></span>`);
+  });
+});

tools/benchmarks/owl-0.13.0/app.js

@@ -1,9 +1,4 @@
-import {
-  buildData,
-  startMeasure,
-  stopMeasure,
-  formatNumber
-} from "../shared/utils.js";
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
 
 //------------------------------------------------------------------------------
 // Likes Counter Widget
@@ -40,11 +35,7 @@ class App extends owl.Component {
   state = { messages: [], multipleFlag: false, clearAfterFlag: false };
 
   mounted() {
-    this.log(
-      `Benchmarking Owl v${owl.__info__.version} (build date: ${
-        owl.__info__.date
-      })`
-    );
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
   }
 
   benchmark(message, fn, callback) {

tools/benchmarks/owl-0.14.0/app.js

@@ -1,9 +1,4 @@
-import {
-  buildData,
-  startMeasure,
-  stopMeasure,
-  formatNumber
-} from "../shared/utils.js";
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
 
 //------------------------------------------------------------------------------
 // Likes Counter Widget
@@ -40,11 +35,7 @@ class App extends owl.Component {
   state = { messages: [], multipleFlag: false, clearAfterFlag: false };
 
   mounted() {
-    this.log(
-      `Benchmarking Owl v${owl.__info__.version} (build date: ${
-        owl.__info__.date
-      })`
-    );
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
   }
 
   benchmark(message, fn, callback) {

tools/benchmarks/owl-0.15.0/app.js

@@ -0,0 +1,161 @@
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps.message !== this.props.message;
+  }
+  removeMessage() {
+    this.trigger("remove-message", {
+      id: this.props.message.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(event) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === event.detail.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.15.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.15.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.15.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="log"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <t t-widget="Message" t-key="message.id" message="message"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.message.author"/></span>
+    <span class="msg"><t t-esc="props.message.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <t t-widget="Counter"/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.16.0/app.js

@@ -0,0 +1,161 @@
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  components = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps.message !== this.props.message;
+  }
+  removeMessage() {
+    this.trigger("remove-message", {
+      id: this.props.message.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  components = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(event) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === event.detail.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.16.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.16.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.16.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="log"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <Message t-key="message.id" message="message"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.message.author"/></span>
+    <span class="msg"><t t-esc="props.message.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <Counter/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.17.0/app.js

@@ -0,0 +1,161 @@
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  components = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps.message !== this.props.message;
+  }
+  removeMessage() {
+    this.trigger("remove-message", {
+      id: this.props.message.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  components = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        owl.Observer.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(event) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === event.detail.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.17.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.17.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.17.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="log"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <Message t-key="message.id" message="message"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.message.author"/></span>
+    <span class="msg"><t t-esc="props.message.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <Counter/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.18.0/app.js

@@ -0,0 +1,161 @@
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  components = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps.message !== this.props.message;
+  }
+  removeMessage() {
+    this.trigger("remove-message", {
+      id: this.props.message.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  components = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        messages[i] = msg;
+      }
+    });
+  }
+
+  removeMessage(event) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === event.detail.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.18.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.18.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.18.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="log"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <Message t-key="message.id" message="message"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.message.author"/></span>
+    <span class="msg"><t t-esc="props.message.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <Counter/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.21.0/app.js

@@ -0,0 +1,153 @@
+import { buildData, startMeasure, stopMeasure, formatNumber } from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  static components = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps.message !== this.props.message;
+  }
+  removeMessage() {
+    this.trigger("remove-message", {
+      id: this.props.message.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  static components = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(`Benchmarking Owl v${owl.__info__.version} (build date: ${owl.__info__.date})`);
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        messages[i] = msg;
+      }
+    });
+  }
+
+  removeMessage(event) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === event.detail.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();