[FIX] crash when rendering component before mounting

This commit makes sure that Owl does not crash when a component is
created, then updated (for example, with a (observed) state change), and
then, some moment later, mounted.

The initial render is not useful, because it is not linked to a mounting
action anyway.  And it caused issues such as a crash when Owl tried to
patch it to a non existing target

.github/workflows/deploy.yml

@@ -0,0 +1,27 @@
+# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
+
+name: Node.js CI
+
+on:
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [10.x, 12.x, 14.x]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v1
+      with:
+        node-version: ${{ matrix.node-version }}
+    - run: npm install
+    - run: npm run test
+    - run: npm run prettier

.gitignore

@@ -26,4 +26,6 @@ node_modules
 # Extras temp file
 /tools/owl.js
 
-release-notes.md
+release-notes.md
+
+.rpt2_cache

README.md

@@ -41,7 +41,7 @@ find some more additional information [here](doc/miscellaneous/comparison.md).
 Here is a short example to illustrate interactive components:
 
 ```javascript
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 const { xml } = owl.tags;
 
 class Counter extends Component {
@@ -63,8 +63,7 @@ class App extends Component {
   static components = { Counter };
 }
 
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 ```
 
 Note that the counter component is made reactive with the [`useState` hook](doc/reference/hooks.md#usestate).
@@ -121,8 +120,7 @@ npm install @odoo/owl
 
 If you want to use a simple `<script>` tag, the last release can be downloaded here:
 
-- [owl-1.0.10.js](https://github.com/odoo/owl/releases/download/v1.0.10/owl.js)
-- [owl-1.0.10.min.js](https://github.com/odoo/owl/releases/download/v1.0.10/owl.min.js)
+- [owl-1.2.2](https://github.com/odoo/owl/releases/tag/v1.2.2)
 
 ## License
 

doc/learning/how_to_test.md

@@ -85,8 +85,7 @@ afterEach(() => {
 describe("SomeComponent", () => {
   test("component behaves as expected", async () => {
     const props = {...}; // depends on the component
-    const comp = new SomeComponent(null, props);
-    await comp.mount(fixture);
+    const comp = await mount(SomeComponent, { target: fixture, props });
 
     // do some assertions
     expect(...).toBe(...);

doc/learning/overview.md

@@ -96,7 +96,7 @@ class OrderLine extends Component {
     </div>`;
 
   add() {
-    this.trigger("add-to-order", { line: props.line });
+    this.trigger("add-to-order", { line: this.props.line });
   }
 }
 

doc/learning/quick_start.md

@@ -54,7 +54,7 @@ Now, `index.html` should contain the following:
 And `app.js` should look like this:
 
 ```js
-const { Component } = owl;
+const { Component, mount } = owl;
 const { xml } = owl.tags;
 const { whenReady } = owl.utils;
 
@@ -65,8 +65,7 @@ class App extends Component {
 
 // Setup code
 function setup() {
-  const app = new App();
-  app.mount(document.body);
+  mount(App, target: { document.body })
 }
 
 whenReady(setup);
@@ -124,7 +123,7 @@ Here is the content of `app.js` and `main.js`:
 
 ```js
 // app.js ----------------------------------------------------------------------
-const { Component } = owl;
+const { Component, mount } = owl;
 const { xml } = owl.tags;
 
 export class App extends Component {
@@ -135,8 +134,7 @@ export class App extends Component {
 import { App } from "./app.js";
 
 function setup() {
-  const app = new App();
-  app.mount(document.body);
+  mount(App, { target: document.body });
 }
 
 owl.utils.whenReady(setup);
@@ -240,12 +238,11 @@ export class App extends Component {
 }
 
 // src/main.js -----------------------------------------------------------------
-import { utils } from "@odoo/owl";
+import { utils, mount } from "@odoo/owl";
 import { App } from "./components/App";
 
 function setup() {
-  const app = new App();
-  app.mount(document.body);
+  mount(App, { target: document.body });
 }
 
 utils.whenReady(setup);
@@ -253,6 +250,7 @@ utils.whenReady(setup);
 // tests/components/App.test.js ------------------------------------------------
 import { App } from "../../src/components/App";
 import { makeTestFixture, nextTick, click } from "../helpers";
+import { mount } from "@odoo/owl";
 
 let fixture;
 
@@ -266,8 +264,7 @@ afterEach(() => {
 
 describe("App", () => {
   test("Works as expected...", async () => {
-    const app = new App();
-    await app.mount(fixture);
+    await mount(App, { target: fixture });
     expect(fixture.innerHTML).toBe("<div>Hello Owl</div>");
 
     click(fixture, "div");

doc/learning/tutorial_todoapp.md

@@ -83,7 +83,7 @@ a single root component. Let us start by defining an `App` component. Replace th
 content of the function in `app.js` by the following code:
 
 ```js
-const { Component } = owl;
+const { Component, mount } = owl;
 const { xml } = owl.tags;
 const { whenReady } = owl.utils;
 
@@ -94,8 +94,7 @@ class App extends Component {
 
 // Setup code
 function setup() {
-  const app = new App();
-  app.mount(document.body);
+  mount(App, { target: document.body });
 }
 
 whenReady(setup);
@@ -279,8 +278,7 @@ class App extends Component {
 // -------------------------------------------------------------------------
 function setup() {
     owl.config.mode = "dev";
-    const app = new App();
-    app.mount(document.body);
+    mount(App, { target: document.body });
 }
 
 whenReady(setup);
@@ -547,7 +545,7 @@ application), since it involves extracting all task related code out of the
 components. Here is the new content of the `app.js` file:
 
 ```js
-const { Component, Store } = owl;
+const { Component, Store, mount } = owl;
 const { xml } = owl.tags;
 const { whenReady } = owl.utils;
 const { useRef, useDispatch, useStore } = owl.hooks;
@@ -639,8 +637,7 @@ function setup() {
   owl.config.mode = "dev";
   const store = new Store({ actions, state: initialState });
   App.env.store = store;
-  const app = new App();
-  app.mount(document.body);
+  mount(App, { target: document.body });
 }
 
 whenReady(setup);
@@ -666,9 +663,8 @@ function makeStore() {
 
 function setup() {
   owl.config.mode = "dev";
-  App.env.store = makeStore();
-  const app = new App();
-  app.mount(document.body);
+  const env = {store = makeStore()};
+  mount(App, { target: document.body, env });
 }
 ```
 
@@ -812,7 +808,7 @@ For reference, here is the final code:
 
 ```js
 (function () {
-  const { Component, Store } = owl;
+  const { Component, Store, mount } = owl;
   const { xml } = owl.tags;
   const { whenReady } = owl.utils;
   const { useRef, useDispatch, useState, useStore } = owl.hooks;
@@ -943,9 +939,8 @@ For reference, here is the final code:
 
   function setup() {
     owl.config.mode = "dev";
-    App.env.store = makeStore();
-    const app = new App();
-    app.mount(document.body);
+    const env = {store = makeStore()};
+    mount(App, { target: document.body, env });
   }
 
   whenReady(setup);

doc/miscellaneous/why_owl.md

@@ -61,14 +61,14 @@ because a lot of the state is hidden in their internals.
 
 React or Vue have a huge community, and a lot of effort have been made into their
 tooling. This is wonderful, but at the same time, a pretty big issue for Odoo:
-since the assets are totally dynamic (and could change whenever the user install
-or remove an addon), we need to have all that kind of tooling on the production
+since the assets are totally dynamic (and could change whenever the user installs
+or removes an addon), we need to have all that kind of tooling on the production
 servers. This is certainly not ideal.
 
 Also, this makes it very complicated to setup Vue or React tools: Odoo code is
 not a simple file that import other files. It changes all the time, assets
 are bundled differently in different contexts. This is the reason why Odoo has
-its own module system, which are resolve at runtime, by the browser. The
+its own module system, which are resolved at runtime, by the browser. The
 dynamic nature of Odoo means that we often need to delay work as late as possible
 (in other word, we want a JIT user interface!)
 
@@ -78,12 +78,12 @@ deploy. Using React without JSX, or Vue without vue file is not very appealing.
 At the same time, Owl is designed to solve this issue: it compiles templates
 by the browser, it doesn't need much code for that, since we use the XML parser
 built into each browser. Owl works with or without any additional tooling. It
-can use template strings to write single file component, and is easy to integrate
+can use template strings to write single file components, and is easy to integrate
 in any html page, with a simple `<script>` tag.
 
 ## Template based
 
-Odoo stores template as XML document in a database. This is very powerful, since
+Odoo stores templates as XML documents in a database. This is very powerful, since
 this allow the use of xpaths to customize other templates. This is a very
 important feature of odoo, and one of the key to Odoo modularity.
 
@@ -104,12 +104,12 @@ awkward, and very confusing.
 ## Developer Experience
 
 This brings us to the following point: developer experience. We see this choice
-as an investment for the future, and we want to make onboarding developer as
+as an investment for the future, and we want to make onboarding developers as
 easy as possible.
 
 While many javascript professionals clearly think that react/vue is not difficult
 (which is true to some extent), it is alsy true that many non js specialists are
-overwhelmed with the frontend world: functional component, hooks, and many other
+overwhelmed with the frontend world: functional components, hooks, and many other
 fancy words. Also, what is available in the compilation context may be difficult,
 there is a lot of black magic going on in pretty much every framework. Vue
 somehow join various namespaces into one, under the hood, and add various internal
@@ -135,7 +135,7 @@ needs: Odoo will fetch templates from the database and need to compile them only
 at the last possible moment, so we can apply all necessary xpaths.
 
 Even more: Odoo needs to be able to generate (and compile) templates at runtime.
-Currently, Odoo form views interpret a xml description. But the form view code
+Currently, Odoo form views interpret an xml description. But the form view code
 then needs to do a lot of complicated operations. With Owl, we will be able to
 transform a view description into a QWeb template, then compile that and use it
 immediately.
@@ -147,16 +147,16 @@ For example, the reactivity system. We like the way Vue did it, but it has a
 flaw: it is not really optional. There is actually a way to opt out of the reactivity
 system by freezing the state, but then, it is freezed.
 
-And there certainly are situations where we need a state, which is not readonly,
+And there certainly are situations where we need a state, which is not read-only,
 and not observed. For example, imagine a spreadsheet component. It may have a
 very large internal state, and it knows exactly when it needs to be rendered
-(basically, whenever the user perform some action). Then, observing its state
+(basically, whenever the user performs some action). Then, observing its state
 is a net performance loss, both for the CPU and the memory.
 
 ## Concurrency
 
 Many applications are happy to simply display a spinner whenever a new asynchronous
-action is performed, but Odoo want a different user experience: most asynchronous
+action is performed, but Odoo wants a different user experience: most asynchronous
 state changes are not displayed until ready. This is sometimes called a concurrent
 mode: the UI is rendered in memory, and displayed only when it is ready (and
 only if it has not been cancelled by subsequent user actions).
@@ -175,6 +175,6 @@ that current standard frameworks are not tailored to our needs. It is perfectly
 fine, because they each chose a different set of tradeoffs.
 
 However, we feel that there is still room in the framework world for something
-that is different. For a framework that make choices compatible with Odoo.
+that is different. For a framework that makes choices compatible with Odoo.
 
 And that is why we built Owl 🦉.

doc/readme.md

@@ -17,6 +17,7 @@ You will find here a complete reference of every feature, class or object
 provided by Owl.
 
 - [Animations](reference/animations.md)
+- [Browser](reference/browser.md)
 - [Component](reference/component.md)
 - [Content](reference/content.md)
 - [Concurrency Model](reference/concurrency_model.md)
@@ -27,6 +28,7 @@ provided by Owl.
 - [Event Handling](reference/event_handling.md)
 - [Error Handling](reference/error_handling.md)
 - [Hooks](reference/hooks.md)
+- [Mounting a component](reference/mounting.md)
 - [Miscellaneous Components](reference/misc.md)
 - [Observer](reference/observer.md)
 - [Props](reference/props.md)

doc/reference/animations.md

@@ -52,21 +52,20 @@ sequence of events will happen:
 At node insertion:
 
 - the css classes `name-enter` and `name-enter-active` will be added directly
-  when the node is inserted into the DOM,
+  when the node is inserted into the DOM.
 - on the next animation frame: the css class `name-enter` will be removed and the
   class `name-enter-to` will be added (so they can be used to trigger css
-  transition effects),
-- the css class `name-enter-active` will be removed whenever a css transition
-  ends.
+  transition effects).
+- at the end of the transition, `name-enter-to` and `name-enter-active` will be removed.
 
 At node destruction:
 
 - the css classes `name-leave` and `name-leave-active` will be added before the
-  node is removed to the DOM,
-- the css class `name-leave` will be removed on the next animation frame (so it
-  can be used to trigger css transition effects),
-- the css class `name-leave-active` will be removed whenever a css transition
-  ends. Only then will the element be removed from the DOM.
+  node is removed to the DOM.
+- on the next animation frame: the css class `name-leave` will be removed and the
+  class `name-leave-to` will be added (so they can be used to trigger css
+  transition effects).
+- at the end of the transition, `name-leave-to` and `name-leave-active` will be removed.
 
 For example, a simple fade in/out effect can be done with this:
 
@@ -93,3 +92,36 @@ Notes:
 
 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).
+
+## SCSS Mixins
+
+If you use SCSS, you can use mixins to make generic animations. Here is an exemple with a fade in / fade out animation:
+
+```scss
+@mixin animation-fade($time, $name) {
+  .#{$name}_fade-enter-active,
+  .#{$name}_fade-active {
+    transition: all $time;
+  }
+
+  .#{$name}_fade-enter {
+    opacity: 0;
+  }
+
+  .#{$name}_fade-leave-to {
+    opacity: 0;
+  }
+}
+```
+
+Usage:
+
+```scss
+@include animation-fade(0.5s, "o_notification");
+```
+
+You can now have in your template:
+
+```xml
+<SomeTag  t-transition="o_notification_fade"/>
+```

doc/reference/browser.md

@@ -0,0 +1,33 @@
+# 🦉 Browser 🦉
+
+## Content
+
+- [Overview](#overview)
+- [Browser Content](#browser-content)
+
+## Overview
+
+The browser object contains some browser native APIs, such as `setTimeout`, that
+are used by Owl and its utility functions. They are exposed with the intent of
+making them mockable if necessary.
+
+```js
+owl.browser.setTimeout === window.setTimeout; // return true
+```
+
+For now, this object contains some functions that are not used by Owl. They
+will eventually be removed in Owl 2.0.
+
+## Browser Content
+
+More specifically, the `browser` object contains the following methods and objects:
+
+- `setTimeout`
+- `clearTimeout`
+- `setInterval`
+- `clearInterval`
+- `requestAnimationFrame`
+- `random`
+- `Date`
+- `fetch`
+- `localStorage`

doc/reference/component.md

@@ -10,13 +10,21 @@
   - [Static Properties](#static-properties)
   - [Methods](#methods)
   - [Lifecycle](#lifecycle)
+    - [`constructor(parent, props)`](#constructorparent-props)
+    - [`willStart()`](#willstart)
+    - [`mounted()`](#mounted)
+    - [`willUpdateProps(nextProps)`](#willupdatepropsnextprops)
+    - [`willPatch()`](#willpatch)
+    - [`patched(snapshot)`](#patchedsnapshot)
+    - [`willUnmount()`](#willunmount)
+    - [`catchError(error)`](#catcherrorerror)
   - [Root Component](#root-component)
   - [Composition](#composition)
   - [Form Input Bindings](#form-input-bindings)
   - [References](#references)
   - [Dynamic sub components](#dynamic-sub-components)
   - [Functional Components](#functional-components)
-  - [SVG components](#svg-components)
+  - [SVG Components](#svg-components)
 
 ## Overview
 
@@ -270,6 +278,10 @@ We explain here all the public methods of the `Component` class.
   // app is now visible
   ```
 
+  Note that the normal way of mounting an application is by using the `mount`
+  method on a component class, not by creating the instance by hand. See the
+  documentation on [mounting applications](mounting.md).
+
 * **`unmount()`**: in case a component needs to be detached/removed from the DOM, this
   method can be used. Most applications should not call `unmount`, this is more
   useful to the underlying component system.
@@ -285,8 +297,13 @@ We explain here all the public methods of the `Component` class.
   are updated. It returns a boolean, which indicates if the component should
   ignore a props update. If it returns false, then `willUpdateProps` will not
   be called, and no rendering will occur. Its default implementation is to
-  always return true. This is an optimization, similar to React's `shouldComponentUpdate`. Most of the time, this should not be used, but it
-  can be useful if we are handling large number of components.
+  always return true. Note that this is an optimization, similar to React's `shouldComponentUpdate`. Most of the time, this should not be used, but it
+  can be useful if we are handling large number of components. Since this is an
+  optimization, Owl has the freedom to ignore the result of `shouldUpdate` in
+  some cases (for example, if a component is remounted, or if we want to force
+  a full rerender of the UI). However, if `shouldUpdate` returns true, then Owl
+  provides the guarantee that the component will be rendered at some point in
+  the future (except if the component is destroyed or if some part of the UI crashes).
 
 * **`destroy()`**. As its name suggests, this method will remove the component,
   and perform all necessary cleanup, such as unmounting the component, its children,

doc/reference/config.md

@@ -2,9 +2,10 @@
 
 The Owl framework is designed to work in many situations. However, it is
 sometimes necessary to customize some behaviour. This is done by using the
-global `config` object. It currently has one key:
+global `config` object. It provides two settings:
 
-- [`mode`](#mode).
+- [`mode`](#mode) (default value: `prod`),
+- [`enableTransitions`](#enabletransitions) (default value: `true`).
 
 ## Mode
 
@@ -25,3 +26,19 @@ 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.
+
+## `enableTransitions`
+
+Transitions are usually nice, but they can cause issues in some specific cases,
+such as automated tests. It is uncomfortable having to wait for a transition
+to end before moving to the next step.
+
+To solve this issue, Owl can be configured to ignore the `t-transition` directive.
+To do that, one only needs to set the `enableTransitions` flag to false:
+
+```js
+owl.config.enableTransitions = false;
+```
+
+Note that it suffers from the same drawback as the "dev" mode: all compiled
+templates, if any, will keep their current behaviours.

doc/reference/content.md

@@ -7,13 +7,15 @@ For example, `Component` is available at `owl.Component` and `EventBus` is
 exported as `owl.core.EventBus`.
 
 ```
+browser
 Component                               misc
 Context                                     AsyncRoot
 QWeb                                        Portal
-Store                                   router
-useState                                    Link
-config                                      RouteComponent
-    mode                                    Router
+mount                                   router
+Store                                       Link
+useState                                    RouteComponent
+config                                      Router
+    mode
 core                                    tags
     EventBus                                css
     Observer                                xml
@@ -27,6 +29,8 @@ hooks                                   utils
     useContext
     useState
     useRef
+    useComponent
+    useEnv
     useSubEnv
     useStore
     useDispatch

doc/reference/environment.md

@@ -49,15 +49,14 @@ The correct way to customize an environment is to simply set it up on the root
 component class, before the first component is created:
 
 ```js
-App.env = {
+const env = {
     _t: myTranslateFunction,
     user: {...},
     services: {
         ...
     },
 };
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body, env });
 ```
 
 It is also possible to simply share an environment between all root components,
@@ -121,9 +120,8 @@ async function myEnv() {
 }
 
 async function start() {
-  App.env = await myEnv();
-  const app = new App();
-  await app.mount(document.body);
+  const env = await myEnv();
+  mount(App, { target: document.body, env });
 }
 ```
 
@@ -135,17 +133,4 @@ the `QWeb` instance and a `browser` object:
 - `qweb` will be set to an empty `QWeb` instance. This is absolutely necessary
   for Owl to be able to render anything
 - `browser`: this is an object that contains some common access points to the
-  browser methods with a side effect. This is particularly useful when one want
-  to test more advanced components, and be able to mock those methods.
-
-More specifically, the `browser` object contains the following methods and objects:
-
-- `setTimeout`
-- `clearTimeout`
-- `setInterval`
-- `clearInterval`
-- `requestAnimationFrame`
-- `random`
-- `Date`
-- `fetch`
-- `localStorage`
+  browser methods with a side effect. See [browser](browser.md) for more information. Note that the browser object will be removed from the environment in Owl 2.0.

doc/reference/event_handling.md

@@ -78,6 +78,20 @@ The `t-on` directive allows to prebind its arguments. For example,
 Here, `expr` is a valid Owl expression, so it could be `true` or some variable
 from the rendering context.
 
+### Type Hinting
+
+Note that if you work with Typescript, the `trigger` method is generic on the type of the payload.
+
+You can then describe the type of the event, so you will see typing errors...
+
+```typescript
+this.trigger<MyCustomPayload>("my-custom-event", payload);
+```
+
+```typescript
+myCustomEventHandler(ev: OwlEvent<MyCustomPayload>) { ... }
+```
+
 ## Inline Event Handlers
 
 One can also directly specify inline statements. For example,

doc/reference/hooks.md

@@ -21,6 +21,8 @@
   - [`useStore`](#usestore)
   - [`useDispatch`](#usedispatch)
   - [`useGetters`](#usegetters)
+  - [`useComponent`](#usecomponent)
+  - [`useEnv`](#useenv)
   - [Making customized hooks](#making-customized-hooks)
 
 ## Overview
@@ -381,6 +383,16 @@ The `useDispatch` hook is the way for components to get a reference to the store
 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.
 
+### `useComponent`
+
+The `useComponent` hook is useful as a building block for some customized hooks,
+that may need a reference to the component calling them.
+
+### `useEnv`
+
+The `useEnv` hook is useful as a building block for some customized hooks,
+that may need a reference to the env of the component calling them.
+
 ### Making customized hooks
 
 Hooks are a wonderful way to organize the code of a complex component by feature
@@ -435,13 +447,11 @@ not the solution to every problem.
 
   ```js
   function useRouter() {
-    return Component.current.env.router;
+    const env = useEnv();
+    return 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/reference/misc.md

@@ -43,7 +43,7 @@ workflow to help the user put in some data, which it could use later on.
 JavaScript:
 
 ```js
-const { Component } = owl;
+const { Component, mount } = owl;
 const { Portal } = owl.misc;
 
 class TeleportedComponent extends Component {}
@@ -51,8 +51,7 @@ class App extends Component {
   static components = { Portal, TeleportedComponent };
 }
 
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 ```
 
 XML:

doc/reference/mounting.md

@@ -0,0 +1,60 @@
+# 🦉 Mounting an application 🦉
+
+## Content
+
+- [Overview](#overview)
+- [API](#api)
+
+## Overview
+
+Mounting an Owl application is done by using the `mount` method (available in
+`owl.mount` if you are using the iife build, or it can be directly imported
+from `owl` if you are using a module system):
+
+```js
+const mount = { owl }; // if owl is available as an object
+
+const env = { ... };
+const app = await mount(MyComponent, { target: document.body, env });
+```
+
+Another example:
+
+```js
+const config = {
+  env: ...,
+  props: ...,
+  target: document.body,
+  position: "self",
+};
+const app = await mount(App, config);
+```
+
+A common way to initialize an application is to first setup an environment,
+then to call the `mount` method.
+
+## API
+
+Mount takes two parameters:
+
+- `C`, which should be a component class (NOT instance),
+- `params`, which is an object with the following keys:
+  - `target (HTMLElement | DocumentFragment)`: the target of the mount operation
+  - `env (optional, Env)` an environment
+  - `position (optional, "first-child" | "last-child" | "self")` the position
+    where it should be mounted (see below for more informations)
+  - `props (optional, any)`: some initial values that are given as props. Useful
+    when the root component is configurable, or when testing sub components
+
+Here are the various positions supported by Owl:
+
+- `first-child`: with this option, the component will be prepended inside the target,
+- `last-child` (default value): with this option, the component will be
+  appended in the target element,
+- `self`: the target will be used as the root element for the component. This
+  means that the target has to be an HTMLElement (and not a document fragment).
+  In this situation, it is possible that the component cannot be unmounted. For
+  example, if its target is `document.body`.
+
+The `mount` method returns a promise that resolves to the instance of the created
+component.

doc/reference/props.md

@@ -18,7 +18,7 @@ class Child extends Component {
 }
 
 class Parent extends Component {
-  static template = xml`<div><ComponentA a="state.a" b="'string'"/></div>`;
+  static template = xml`<div><Child a="state.a" b="'string'"/></div>`;
   static components = { Child };
   state = useState({ a: "fromparent" });
 }

doc/reference/qweb_templating_language.md

@@ -15,6 +15,7 @@
   - [Dynamic Attributes](#dynamic-attributes)
   - [Loops](#loops)
   - [Rendering Sub Templates](#rendering-sub-templates)
+  - [Dynamic Sub Templates](#dynamic-sub-templates)
   - [Translations](#translations)
   - [Debugging](#debugging)
 
@@ -452,6 +453,17 @@ are all equivalent:
 
 If there is no `t-key` directive, Owl will use the index as a default key.
 
+Note: the `t-foreach` directive only accepts arrays (lists) or objects. It does
+not work with other iterables, such as `Set`. However, it is only a matter of
+using the `...` javascript operator. For example:
+
+```xml
+<t t-foreach="...items" t-as="item">...</t>
+```
+
+The `...` operator will convert the `Set` (or any other iterables) into a list,
+which will work with Owl QWeb.
+
 ### Rendering Sub Templates
 
 QWeb templates can be used for top level rendering, but they can also be used
@@ -509,6 +521,22 @@ This can be used to define variables scoped to a sub template:
 <!-- "var" does not exist here -->
 ```
 
+### Dynamic sub templates
+
+The `t-call` directive can also be used to dynamically call a sub template,
+using string interpolation. For example:
+
+```xml
+<div t-name="main-template">
+    <t t-call="{{template}}">
+        <em>content</em>
+    </t>
+</div>
+```
+
+Here, the name of the template is obtained from the `template` value in the
+template rendering context.
+
 ### Translations
 
 By default, QWeb specify that templates should be translated. If this behaviour

doc/reference/slots.md

@@ -25,6 +25,8 @@ some sub template, but still be the owner. For example, a generic dialog compone
 will need to render some content, some footer, but with the parent as the
 rendering context.
 
+Slots are inserted with the `t-slot` directive:
+
 ```xml
 <div t-name="Dialog" class="modal">
   <div class="modal-title"><t t-esc="props.title"/></div>
@@ -62,7 +64,9 @@ This is deprecated and should no longer be used in new code.
 
 ## Reference
 
-Default slot: the first element inside the component which is not a named slot will
+### Default Slot
+
+The first element inside the component which is not a named slot will
 be considered the `default` slot. For example:
 
 ```xml
@@ -77,7 +81,9 @@ be considered the `default` slot. For example:
 </div>
 ```
 
-Default content: slots can define a default content, in case the parent did not define them:
+### Default content
+
+Slots can define a default content, in case the parent did not define them:
 
 ```xml
 <div t-name="Parent">
@@ -94,3 +100,12 @@ Rendering context: the content of the slots is actually rendered with the
 rendering context corresponding to where it was defined, not where it is
 positioned. This allows the user to define event handlers that will be bound
 to the correct component (usually, the grandparent of the slot content).
+
+### Dynamic Slots
+
+The `t-slot` directive is actually able to use any expressions, using string
+interplolation:
+
+```xml
+ <t t-slot="{{current}}" />
+```

doc/reference/utils.md

@@ -21,8 +21,8 @@ argument, it executes it as soon as the DOM ready (or directly).
 ```js
 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);
+  const env = { qweb };
+  await mount(App, { env, target: document.body });
 });
 ```
 
@@ -31,8 +31,8 @@ or alternatively:
 ```js
 owl.utils.whenReady(function () {
   const qweb = new owl.QWeb();
-  const app = new App({ qweb });
-  app.mount(document.body);
+  const env = { qweb };
+  await mount(App, { env, target: document.body });
 });
 ```
 

package.json

@@ -1,23 +1,20 @@
 {
   "name": "@odoo/owl",
-  "version": "1.0.10",
+  "version": "1.2.2",
   "description": "Odoo Web Library (OWL)",
-  "main": "dist/owl.js",
+  "main": "dist/owl.cjs.js",
+  "browser": "dist/owl.iife.js",
+  "module": "dist/owl.es.js",
   "types": "dist/types/index.d.ts",
   "files": [
-    "dist/types/",
-    "dist/owl.js",
-    "dist/owl-iife.js"
+    "dist"
   ],
   "engines": {
     "node": ">=10.15.3"
   },
   "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",
+    "build": "npm run build:bundle",
     "test": "jest",
     "test:watch": "jest --watch",
     "tools:serve": "python3 tools/server.py || python tools/server.py",
@@ -25,7 +22,7 @@
     "pretools:watch": "npm run build",
     "tools:watch": "npm-run-all  --parallel tools:serve \"build:* -- --watch\"",
     "prettier": "prettier {src/*.ts,src/**/*.ts,tests/*.ts,tests/**/*.ts,doc/*.md,doc/**/*.md} --write",
-    "publish": "mv dist/owl.js dist/owl-iife.js && npm run buildcommonjs && npm publish",
+    "publish": "npm run build && npm publish",
     "release": "node tools/release.js"
   },
   "repository": {
@@ -38,20 +35,21 @@
     "url": "https://github.com/odoo/owl/issues"
   },
   "homepage": "https://github.com/odoo/owl#readme",
-  "dependencies": {},
   "devDependencies": {
-    "@types/jest": "^23.3.12",
+    "@types/jest": "^23.3.14",
+    "@types/node": "^14.11.8",
     "chalk": "^3.0.0",
     "cpx": "^1.5.0",
     "git-rev-sync": "^1.12.0",
     "github-api": "^3.3.0",
     "jest": "^23.6.0",
     "jest-environment-jsdom": "^24.7.1",
-    "live-server": "^1.2.1",
+    "live-server": "^1.2.2",
     "npm-run-all": "^4.1.5",
     "prettier": "^2.0.4",
     "rollup": "^1.6.0",
-    "rollup-plugin-typescript2": "^0.20.1",
+    "rollup-plugin-terser": "^7.0.2",
+    "rollup-plugin-typescript2": "^0.27.3",
     "sass": "^1.16.1",
     "source-map-support": "^0.5.10",
     "ts-jest": "^23.10.5",

roadmap.md

@@ -1,6 +1,6 @@
 # 🦉 OWL Roadmap 🦉
 
-- Current version: 1.0.10
+- Current version: 1.2.2
 - Status: stable
 
 This roadmap is only an attempt at predicting Owl's future.  Everything may

rollup.config.js

@@ -1,14 +1,70 @@
-import { version } from "./package.json";
+import pkg from "./package.json";
 import git from "git-rev-sync";
+import typescript from 'rollup-plugin-typescript2';
+import { terser } from "rollup-plugin-terser";
+
+const name = "owl";
+const extend = true;
+
+/**
+ * Meta data to be added on the __info__ object.
+ * Used to let external tools know the current owl version.
+ */
+const outro = `
+__info__.version = '${pkg.version}';
+__info__.date = '${new Date().toISOString()}';
+__info__.hash = '${git.short()}';
+__info__.url = 'https://github.com/odoo/owl';
+`;
+
+/**
+ * Generate from a string depicting a path a new path for the minified version.
+ * @param {string} pkgFileName file name
+ */
+function generateMinifiedNameFromPkgName(pkgFileName) {
+  const parts = pkgFileName.split('.');
+  parts.splice(parts.length - 1, 0, "min");
+  return parts.join('.');
+}
+
+/**
+ * Get the rollup config based on the arguments
+ * @param {string} format format of the bundle
+ * @param {string} generatedFileName generated file name
+ * @param {boolean} minified should it be minified
+ */
+function getConfigForFormat(format, generatedFileName, minified = false) {
+  return {
+    file: minified ? generateMinifiedNameFromPkgName(generatedFileName) : generatedFileName,
+    format: format,
+    name: name,
+    extend: extend,
+    outro: outro,
+    plugins: minified ? [terser()] : [],
+    indent: '    ', // indent with 4 spaces
+  };
+}
 
-// rollup.config.js
 export default {
-  input: "dist/owl/index.js",
-  output: {
-    file: "dist/owl.js",
-    format: "iife",
-    name: "owl",
-    extend: true,
-    outro: `exports.__info__.version = '${version}';\nexports.__info__.date = '${new Date().toISOString()}';\nexports.__info__.hash = '${git.short()}';\nexports.__info__.url = 'https://github.com/odoo/owl';`
-  }
+  input: "src/index.ts",
+  output: [
+
+    /**
+     * Read about module formats:
+     *  https://auth0.com/blog/javascript-module-systems-showdown/
+     *  https://medium.com/@kelin2025/so-you-wanna-use-es6-modules-714f48b3a953
+     */
+
+    getConfigForFormat('esm', pkg.module),
+    getConfigForFormat('esm', pkg.module, true),
+    getConfigForFormat('cjs', pkg.main),
+    getConfigForFormat('cjs', pkg.main, true),
+    getConfigForFormat('iife', pkg.browser),
+    getConfigForFormat('iife', pkg.browser, true),
+  ],
+  plugins: [
+    typescript({
+      useTsconfigDeclarationDir: true
+    }),
+  ]
 };

src/browser.ts

@@ -10,6 +10,8 @@ export interface Browser {
   localStorage: Window["localStorage"];
 }
 
+let localStorage: Window["localStorage"] | null = null;
+
 export const browser: Browser = {
   setTimeout: window.setTimeout.bind(window),
   clearTimeout: window.clearTimeout.bind(window),
@@ -19,5 +21,10 @@ export const browser: Browser = {
   random: Math.random,
   Date: window.Date,
   fetch: (window.fetch || (() => {})).bind(window),
-  localStorage: window.localStorage,
+  get localStorage() {
+    return localStorage || window.localStorage;
+  },
+  set localStorage(newLocalStorage: Window["localStorage"]) {
+    localStorage = newLocalStorage;
+  },
 };

src/component/component.ts

@@ -159,6 +159,7 @@ export class Component<Props extends {} = any, T extends Env = Env> {
       if (!this.env.qweb) {
         this.env.qweb = new QWeb();
       }
+      // TODO: remove this in owl 2.0
       if (!this.env.browser) {
         this.env.browser = browser;
       }
@@ -321,7 +322,14 @@ export class Component<Props extends {} = any, T extends Env = Env> {
     }
     if (__owl__.currentFiber) {
       const currentFiber = __owl__.currentFiber;
-      if (currentFiber.target === target && currentFiber.position === position) {
+      if (!currentFiber.target && !currentFiber.position) {
+        // this means we have a pending rendering, but it was a render operation,
+        // not a mount operation. We can simply update the fiber with the target
+        // and the position
+        currentFiber.target = target;
+        currentFiber.position = position;
+        return scheduler.addFiber(currentFiber);
+      } else if (currentFiber.target === target && currentFiber.position === position) {
         return scheduler.addFiber(currentFiber);
       } else {
         scheduler.rejectFiber(currentFiber, "Mounting operation cancelled");
@@ -332,7 +340,7 @@ export class Component<Props extends {} = any, T extends Env = Env> {
       message += `\nMaybe the DOM is not ready yet? (in that case, you can use owl.utils.whenReady)`;
       throw new Error(message);
     }
-    const fiber = new Fiber(null, this, false, target, position);
+    const fiber = new Fiber(null, this, true, target, position);
     fiber.shouldPatch = false;
     if (!__owl__.vnode) {
       this.__prepareAndRender(fiber, () => {});
@@ -365,10 +373,7 @@ export class Component<Props extends {} = any, T extends Env = Env> {
   async render(force: boolean = false): Promise<void> {
     const __owl__ = this.__owl__;
     const currentFiber = __owl__.currentFiber;
-    if (!__owl__.isMounted && !currentFiber) {
-      // if we get here, this means that the component was either never mounted,
-      // or was unmounted and some state change  triggered a render. Either way,
-      // we do not want to actually render anything in this case.
+    if (!__owl__.vnode && !currentFiber) {
       return;
     }
     if (currentFiber && !currentFiber.isRendered && !currentFiber.isCompleted) {
@@ -384,8 +389,6 @@ export class Component<Props extends {} = any, T extends Env = Env> {
         if (fiber.isCompleted) {
           return;
         }
-        // we are mounted (__owl__.isMounted), or if we are currently being
-        // mounted (!isMounted), so we call __render
         this.__render(fiber);
       } else {
         // we were mounted when render was called, but we aren't anymore, so we
@@ -433,8 +436,8 @@ export class Component<Props extends {} = any, T extends Env = Env> {
    * up to the parent DOM nodes. Thus, it must be called between mounted() and
    * willUnmount().
    */
-  trigger(eventType: string, payload?: any) {
-    this.__trigger(this, eventType, payload);
+  trigger<T = any>(eventType: string, payload?: T) {
+    this.__trigger<T>(this, eventType, payload);
   }
 
   //--------------------------------------------------------------------------
@@ -512,9 +515,9 @@ export class Component<Props extends {} = any, T extends Env = Env> {
    * Private trigger method, allows to choose the component which triggered
    * the event in the first place
    */
-  __trigger(component: Component, eventType: string, payload?: any) {
+  __trigger<T>(component: Component, eventType: string, payload?: T) {
     if (this.el) {
-      const ev = new OwlEvent(component, eventType, {
+      const ev = new OwlEvent<T>(component, eventType, {
         bubbles: true,
         cancelable: true,
         detail: payload,
@@ -729,3 +732,34 @@ export class Component<Props extends {} = any, T extends Env = Env> {
     }
   }
 }
+
+interface MountParameters {
+  env?: Env;
+  target: HTMLElement | DocumentFragment;
+  props?: any;
+  position?: MountOptions["position"];
+}
+
+interface Type<T> extends Function {
+  new (...args: any[]): T;
+}
+
+export async function mount<T extends Type<Component>>(
+  C: T,
+  params: MountParameters
+): Promise<InstanceType<T>> {
+  const { env, props, target } = params;
+  let origEnv = C.hasOwnProperty("env") ? (C as any).env : null;
+  if (env) {
+    ((C as any) as typeof Component).env = env;
+  }
+  const component: Component = new C(null, props);
+  if (origEnv) {
+    (C as any).env = origEnv;
+  } else {
+    delete (C as any).env;
+  }
+  const position = params.position || "last-child";
+  await component.mount(target, { position });
+  return component as any;
+}

src/component/directive.ts

@@ -227,7 +227,9 @@ QWeb.addDirective({
       if (name.startsWith("t-on-")) {
         events.push([name, value]);
       } else if (name === "t-transition") {
-        transition = value;
+        if (QWeb.enableTransitions) {
+          transition = value;
+        }
       } else if (!name.startsWith("t-")) {
         if (name !== "class" && name !== "style") {
           // this is a prop!
@@ -400,7 +402,6 @@ QWeb.addDirective({
 
     if (hasSlots) {
       const clone = <Element>node.cloneNode(true);
-      const slotNodes = Array.from(clone.querySelectorAll("[t-set-slot]"));
 
       // The next code is a fallback for compatibility reason. It accepts t-set
       // elements that are direct children with a non empty body as nodes defining
@@ -410,27 +411,45 @@ QWeb.addDirective({
       // code using slots. This will be removed in v2.0 someday. Meanwhile,
       // please use t-set-slot everywhere you need to set the content of a
       // slot.
-      for (let el of clone.children) {
-        if (el.getAttribute("t-set") && el.hasChildNodes()) {
-          slotNodes.push(el);
+      for (let node of clone.children) {
+        if (node.hasAttribute("t-set") && node.hasChildNodes()) {
+          node.setAttribute("t-set-slot", node.getAttribute("t-set")!);
+          node.removeAttribute("t-set");
         }
       }
+      const slotNodes = Array.from(clone.querySelectorAll("[t-set-slot]"));
+      const slotNames = new Set<string>();
       const slotId = QWeb.nextSlotId++;
       ctx.addLine(`w${componentID}.__owl__.slotId = ${slotId};`);
       if (slotNodes.length) {
         for (let i = 0, length = slotNodes.length; i < length; i++) {
           const slotNode = slotNodes[i];
-          slotNode.parentElement!.removeChild(slotNode);
-          let key = slotNode.getAttribute("t-set-slot")!;
-          slotNode.removeAttribute("t-set-slot");
-
-          // here again, this code should be removed when we stop supporting
-          // using t-set to define the content of named slots.
-          if (!key) {
-            key = slotNode.getAttribute("t-set")!;
-            slotNode.removeAttribute("t-set");
+          // check if this is defined in a sub component (in which case it should
+          // be ignored)
+          let el = slotNode.parentElement;
+          let isInSubComponent = false;
+          while (el !== clone) {
+            if (
+              el!.hasAttribute("t-component") ||
+              el!.tagName[0] === el!.tagName[0].toUpperCase()
+            ) {
+              isInSubComponent = true;
+              break;
+            }
+            el = el.parentElement;
           }
-          const slotFn = qweb._compile(`slot_${key}_template`, slotNode, ctx);
+          if (isInSubComponent) {
+            continue;
+          }
+          let key = slotNode.getAttribute("t-set-slot")!;
+          if (slotNames.has(key)) {
+            continue;
+          }
+          slotNames.add(key);
+          slotNode.removeAttribute("t-set-slot");
+          slotNode.parentElement!.removeChild(slotNode);
+
+          const slotFn = qweb._compile(`slot_${key}_template`, { elem: slotNode, hasParent: true });
           QWeb.slots[`${slotId}_${key}`] = slotFn;
         }
       }
@@ -439,7 +458,7 @@ QWeb.addDirective({
         for (let child of Object.values(clone.childNodes)) {
           t.appendChild(child);
         }
-        const slotFn = qweb._compile(`slot_default_template`, t, ctx);
+        const slotFn = qweb._compile(`slot_default_template`, { elem: t, hasParent: true });
         QWeb.slots[`${slotId}_default`] = slotFn;
       }
     }

src/component/fiber.ts

@@ -82,6 +82,7 @@ export class Fiber {
 
     let oldFiber = __owl__.currentFiber;
     if (oldFiber && !oldFiber.isCompleted) {
+      this.force = true;
       if (oldFiber.root === oldFiber && !parent) {
         // both oldFiber and this fiber are root fibers
         this._reuseFiber(oldFiber);
@@ -187,7 +188,8 @@ export class Fiber {
   complete() {
     let component = this.component;
     this.isCompleted = true;
-    if (!this.target && !component.__owl__.isMounted) {
+    const { isMounted, isDestroyed } = component.__owl__;
+    if (isDestroyed) {
       return;
     }
 
@@ -201,14 +203,16 @@ export class Fiber {
     const patchLen = patchQueue.length;
 
     // call willPatch hook on each fiber of patchQueue
-    for (let i = 0; i < patchLen; i++) {
-      const fiber = patchQueue[i];
-      if (fiber.shouldPatch) {
-        component = fiber.component;
-        if (component.__owl__.willPatchCB) {
-          component.__owl__.willPatchCB();
+    if (isMounted) {
+      for (let i = 0; i < patchLen; i++) {
+        const fiber = patchQueue[i];
+        if (fiber.shouldPatch) {
+          component = fiber.component;
+          if (component.__owl__.willPatchCB) {
+            component.__owl__.willPatchCB();
+          }
+          component.willPatch();
         }
-        component.willPatch();
       }
     }
 
@@ -270,16 +274,18 @@ export class Fiber {
     }
 
     // call patched/mounted hook on each fiber of (reversed) patchQueue
-    for (let i = patchLen - 1; i >= 0; i--) {
-      const fiber = patchQueue[i];
-      component = fiber.component;
-      if (fiber.shouldPatch && !this.target) {
-        component.patched();
-        if (component.__owl__.patchedCB) {
-          component.__owl__.patchedCB();
+    if (isMounted || inDOM) {
+      for (let i = patchLen - 1; i >= 0; i--) {
+        const fiber = patchQueue[i];
+        component = fiber.component;
+        if (fiber.shouldPatch && !this.target) {
+          component.patched();
+          if (component.__owl__.patchedCB) {
+            component.__owl__.patchedCB();
+          }
+        } else {
+          component.__callMounted();
         }
-      } else if (this.target ? inDOM : true) {
-        component.__callMounted();
       }
     }
   }

src/config.ts

@@ -8,6 +8,7 @@ import { QWeb } from "./qweb/index";
 
 interface Config {
   mode: string;
+  enableTransitions: boolean;
 }
 
 export const config = {} as Config;
@@ -28,3 +29,12 @@ Object.defineProperty(config, "mode", {
     }
   },
 });
+
+Object.defineProperty(config, "enableTransitions", {
+  get() {
+    return QWeb.enableTransitions;
+  },
+  set(value: boolean) {
+    QWeb.enableTransitions = value;
+  },
+});

src/context.ts

@@ -115,16 +115,6 @@ export function useContextWithCB(ctx: Context, component: Component, method): an
     __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;

src/hooks.ts

@@ -1,4 +1,4 @@
-import { Component } from "./component/component";
+import { Component, Env } from "./component/component";
 import { Observer } from "./core/observer";
 
 /**
@@ -118,6 +118,26 @@ export function useRef<C extends Component = Component>(name: string): Ref<C> {
   };
 }
 
+// -----------------------------------------------------------------------------
+// "Builder" hooks
+// -----------------------------------------------------------------------------
+
+/**
+ * This hook is useful as a building block for some customized hooks, that may
+ * need a reference to the component calling them.
+ */
+export function useComponent<P, E extends Env>(): Component<P, E> {
+  return Component.current as any;
+}
+
+/**
+ * This hook is useful as a building block for some customized hooks, that may
+ * need a reference to the env of the component calling them.
+ */
+export function useEnv<E extends Env>(): E {
+  return Component.current.env as any;
+}
+
 // -----------------------------------------------------------------------------
 // useSubEnv
 // -----------------------------------------------------------------------------

src/index.ts

@@ -19,9 +19,10 @@ import { Link } from "./router/link";
 import { RouteComponent } from "./router/route_component";
 import { Router } from "./router/router";
 
-export { Component } from "./component/component";
+export { Component, mount } from "./component/component";
 export { QWeb };
 export { config };
+export { browser } from "./browser";
 
 export const Context = _context.Context;
 export const useState = _hooks.useState;
@@ -37,4 +38,5 @@ export const hooks = Object.assign({}, _hooks, {
   useGetters: _store.useGetters,
   useStore: _store.useStore,
 });
+
 export const __info__ = {};

src/qweb/base_directives.ts

@@ -1,4 +1,4 @@
-import { CompilationContext } from "./compilation_context";
+import { CompilationContext, INTERP_REGEXP } from "./compilation_context";
 import { QWeb } from "./qweb";
 import { htmlToVDOM } from "../vdom/html_to_vdom";
 import { QWebVar } from "./expression_parser";
@@ -224,19 +224,36 @@ QWeb.addDirective({
     ctx.rootContext.shouldDefineScope = true;
     ctx.rootContext.shouldDefineUtils = true;
     const subTemplate = node.getAttribute("t-call")!;
+    const isDynamic = INTERP_REGEXP.test(subTemplate);
     const nodeTemplate = qweb.templates[subTemplate];
-    if (!nodeTemplate) {
+    if (!isDynamic && !nodeTemplate) {
       throw new Error(`Cannot find template "${subTemplate}" (t-call)`);
     }
 
     // Step 2: compile target template in sub templates
     // ------------------------------------------------
-    let subId = qweb.subTemplates[subTemplate];
-    if (!subId) {
-      subId = QWeb.nextId++;
-      qweb.subTemplates[subTemplate] = subId;
-      const subTemplateFn = qweb._compile(subTemplate, nodeTemplate.elem, ctx, true);
-      QWeb.subTemplates[subId] = subTemplateFn;
+    let subIdstr: string;
+    if (isDynamic) {
+      const _id = ctx.generateID();
+      ctx.addLine(`let tname${_id} = ${ctx.interpolate(subTemplate)};`);
+      ctx.addLine(`let tid${_id} = this.subTemplates[tname${_id}];`);
+      ctx.addIf(`!tid${_id}`);
+      ctx.addLine(`tid${_id} = this.constructor.nextId++;`);
+      ctx.addLine(`this.subTemplates[tname${_id}] = tid${_id};`);
+      ctx.addLine(
+        `this.constructor.subTemplates[tid${_id}] = this._compile(tname${_id}, {hasParent: true, defineKey: true});`
+      );
+      ctx.closeIf();
+      subIdstr = `tid${_id}`;
+    } else {
+      let subId = qweb.subTemplates[subTemplate];
+      if (!subId) {
+        subId = QWeb.nextId++;
+        qweb.subTemplates[subTemplate] = subId;
+        const subTemplateFn = qweb._compile(subTemplate, { hasParent: true, defineKey: true });
+        QWeb.subTemplates[subId] = subTemplateFn;
+      }
+      subIdstr = `'${subId}'`;
     }
 
     // Step 3: compile t-call body if necessary
@@ -251,16 +268,13 @@ QWeb.addDirective({
       for (let attr of ["t-if", "t-else", "t-elif", "t-call"]) {
         nodeCopy.removeAttribute(attr);
       }
-      const parentNode = ctx.parentNode;
-      ctx.parentNode = "__0";
       // this local scope is intended to trap c__0
       ctx.addLine(`{`);
       ctx.indent();
       ctx.addLine("let c__0 = [];");
-      qweb._compileNode(nodeCopy, ctx);
+      qweb._compileNode(nodeCopy, ctx.subContext("parentNode", "__0"));
       ctx.rootContext.shouldDefineUtils = true;
       ctx.addLine("scope[utils.zero] = c__0;");
-      ctx.parentNode = parentNode;
       ctx.dedent();
       ctx.addLine(`}`);
     }
@@ -272,12 +286,12 @@ QWeb.addDirective({
     const parentNode = ctx.parentNode ? `c${ctx.parentNode}` : "result";
     const extra = `Object.assign({}, extra, {parentNode: ${parentNode}, parent: ${parentComponent}, key: ${key}})`;
     if (ctx.parentNode) {
-      ctx.addLine(`this.constructor.subTemplates['${subId}'].call(this, scope, ${extra});`);
+      ctx.addLine(`this.constructor.subTemplates[${subIdstr}].call(this, scope, ${extra});`);
     } else {
       // this is a t-call with no parentnode, we need to extract the result
       ctx.rootContext.shouldDefineResult = true;
       ctx.addLine(`result = []`);
-      ctx.addLine(`this.constructor.subTemplates['${subId}'].call(this, scope, ${extra});`);
+      ctx.addLine(`this.constructor.subTemplates[${subIdstr}].call(this, scope, ${extra});`);
       ctx.addLine(`result = result[0]`);
     }
 

src/qweb/extensions.ts

@@ -1,4 +1,5 @@
 import { VNode } from "../vdom/index";
+import { INTERP_REGEXP } from "./compilation_context";
 import { QWeb } from "./qweb";
 
 /**
@@ -205,6 +206,9 @@ QWeb.addDirective({
   name: "transition",
   priority: 96,
   atNodeCreation({ ctx, value, addNodeHook }) {
+    if (!QWeb.enableTransitions) {
+      return;
+    }
     ctx.rootContext.shouldDefineUtils = true;
     let name = value;
     const hooks = {
@@ -225,8 +229,9 @@ QWeb.addDirective({
   priority: 80,
   atNodeEncounter({ ctx, value, node, qweb }): boolean {
     const slotKey = ctx.generateID();
+    const valueExpr = value.match(INTERP_REGEXP) ? ctx.interpolate(value) : `'${value}'`;
     ctx.addLine(
-      `const slot${slotKey} = this.constructor.slots[context.__owl__.slotId + '_' + '${value}'];`
+      `const slot${slotKey} = this.constructor.slots[context.__owl__.slotId + '_' + ${valueExpr}];`
     );
     ctx.addIf(`slot${slotKey}`);
     let parentNode = `c${ctx.parentNode}`;

src/qweb/qweb.ts

@@ -70,6 +70,7 @@ const TRANSLATABLE_ATTRS = ["label", "title", "placeholder", "alt"];
 
 const lineBreakRE = /[\r\n]/;
 const whitespaceRE = /\s+/g;
+const translationRE = /^(\s*)([\s\S]+?)(\s*)$/;
 
 const NODE_HOOKS_PARAMS = {
   create: "(_, n)",
@@ -212,6 +213,7 @@ export class QWeb extends EventBus {
   h = h;
   // dev mode enables better error messages or more costly validations
   static dev: boolean = false;
+  static enableTransitions: boolean = true;
 
   // slots contains sub templates defined with t-set inside t-component nodes, and
   // are meant to be used by the t-slot directive.
@@ -312,7 +314,7 @@ export class QWeb extends EventBus {
     const template = {
       elem,
       fn: function (this: QWeb, context, extra) {
-        const compiledFunction = this._compile(name, elem);
+        const compiledFunction = this._compile(name);
         template.fn = compiledFunction;
         return compiledFunction.call(this, context, extra);
       },
@@ -417,30 +419,33 @@ export class QWeb extends EventBus {
 
   _compile(
     name: string,
-    elem: Element,
-    parentContext?: CompilationContext,
-    defineKey?: boolean
+    options: {
+      elem?: Element;
+      hasParent?: boolean;
+      defineKey?: boolean;
+    } = {}
   ): CompiledTemplate {
+    const elem = options.elem || this.templates[name].elem;
     const isDebug = elem.attributes.hasOwnProperty("t-debug");
     const ctx = new CompilationContext(name);
     if (elem.tagName !== "t") {
       ctx.shouldDefineResult = false;
     }
-    if (parentContext) {
-      ctx.variables = Object.create(parentContext.variables);
-      ctx.parentNode = parentContext.parentNode || ctx.generateID();
+    if (options.hasParent) {
+      ctx.variables = Object.create(null);
+      ctx.parentNode = ctx.generateID();
       ctx.allowMultipleRoots = true;
       ctx.hasParentWidget = true;
       ctx.shouldDefineResult = false;
       ctx.addLine(`let c${ctx.parentNode} = extra.parentNode;`);
-      if (defineKey) {
+      if (options.defineKey) {
         ctx.addLine(`let key0 = extra.key || "";`);
         ctx.hasKey0 = true;
       }
     }
     this._compileNode(elem, ctx);
 
-    if (!parentContext) {
+    if (!options.hasParent) {
       if (ctx.shouldDefineResult) {
         ctx.addLine(`return result;`);
       } else {
@@ -492,7 +497,8 @@ export class QWeb extends EventBus {
       }
       if (this.translateFn) {
         if ((node.parentNode as any).getAttribute("t-translation") !== "off") {
-          text = this.translateFn(text);
+          const match = translationRE.exec(text);
+          text = match[1] + this.translateFn(match[2]) + match[3];
         }
       }
       if (ctx.parentNode) {

src/store.ts

@@ -1,5 +1,4 @@
-import { Component } from "./component/component";
-import { Env } from "./component/component";
+import { Component, Env } from "./component/component";
 import { Context, useContextWithCB } from "./context";
 import { onWillUpdateProps } from "./hooks";
 
@@ -76,6 +75,11 @@ export class Store extends Context {
     );
     return result;
   }
+
+  __notifyComponents(): Promise<void> {
+    this.trigger("before-update");
+    return super.__notifyComponents();
+  }
 }
 
 interface SelectorOptions {
@@ -106,13 +110,16 @@ export function useStore(selector, options: SelectorOptions = {}): any {
     const newRevNumber = hashFn(result);
     if ((newRevNumber > 0 && revNumber !== newRevNumber) || !isEqual(oldResult, result)) {
       revNumber = newRevNumber;
-      if (options.onUpdate) {
-        options.onUpdate(result);
-      }
       return true;
     }
     return false;
   }
+  if (options.onUpdate) {
+    store.on("before-update", component, () => {
+      const newValue = selector(store!.state, component.props!);
+      options.onUpdate(newValue);
+    });
+  }
   store.updateFunctions[componentId].push(function (): boolean {
     return selectCompareUpdate(store!.state, component.props);
   });
@@ -133,6 +140,9 @@ export function useStore(selector, options: SelectorOptions = {}): any {
   const __destroy = component.__destroy;
   component.__destroy = (parent) => {
     delete store.updateFunctions[componentId];
+    if (options.onUpdate) {
+      store.off("before-update", component);
+    }
     __destroy.call(component, parent);
   };
 

src/vdom/html_to_vdom.ts

@@ -13,6 +13,9 @@ export function htmlToVDOM(html: string): VNode[] {
 
 function htmlToVNode(node: ChildNode): VNode {
   if (!(node instanceof Element)) {
+    if (node instanceof Comment) {
+      return h("!", node.textContent);
+    }
     return { text: node.textContent! } as VNode;
   }
   const attrs = {};

tests/animations.test.ts

@@ -1,15 +1,15 @@
 import { Component, Env } from "../src/component/component";
+import { useRef, useState } from "../src/hooks";
 import { QWeb } from "../src/qweb/index";
-import { useState, useRef } from "../src/hooks";
 import { xml } from "../src/tags";
 import {
   makeDeferred,
-  makeTestFixture,
   makeTestEnv,
+  makeTestFixture,
+  nextFrame,
   patchNextFrame,
   renderToDOM,
   unpatchNextFrame,
-  nextTick,
 } from "./helpers";
 
 //------------------------------------------------------------------------------
@@ -420,29 +420,29 @@ describe("animations", () => {
 
     widget.state.flag = true;
 
-    await nextTick();
+    await nextFrame();
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend"));
     expect(fixture.innerHTML).toBe('<div><span class="">blue</span></div>');
     expect(QWeb.utils.transitionInsert).toBeCalledTimes(1);
 
     widget.state.flag = false;
-    await nextTick();
+    await nextFrame();
     expect(fixture.innerHTML).toBe(
       '<div><span class="chimay-leave-active chimay-leave-to" data-owl-key="__3__">blue</span></div>'
     );
     expect(QWeb.utils.transitionInsert).toBeCalledTimes(1);
 
     widget.state.flag = true;
-    await nextTick();
+    await nextFrame();
     expect(fixture.innerHTML).toBe(
       '<div><span class="chimay-enter-active chimay-enter-to" data-owl-key="__3__">blue</span></div>'
     );
     expect(QWeb.utils.transitionInsert).toBeCalledTimes(2);
 
     widget.state.flag = false;
-    await nextTick();
+    await nextFrame();
     widget.state.flag = true;
-    await nextTick();
+    await nextFrame();
 
     expect(QWeb.utils.transitionInsert).toBeCalledTimes(3);
     widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend"));

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

@@ -534,11 +534,11 @@ exports[`other directives with t-component slot setted value (with t-set) not ac
         w3.__owl__.pvnode = pvnode;
     }
     w3.__owl__.parentLastFiberId = extra.fiber.id;
-    let c5 = [], p5 = {key:5};
-    let vn5 = h('p', p5, c5);
-    c1.push(vn5);
+    let c6 = [], p6 = {key:6};
+    let vn6 = h('p', p6, c6);
+    c1.push(vn6);
     if (scope.iter != null) {
-        c5.push({text: scope.iter});
+        c6.push({text: scope.iter});
     }
     return vn1;
 }"
@@ -1253,16 +1253,16 @@ exports[`other directives with t-component t-set can't alter from within callee
     if (scope.iter != null) {
         c2.push({text: scope.iter});
     }
-    let _origScope4 = scope;
+    let _origScope6 = scope;
     scope = Object.create(scope);
     scope.__access_mode__ = 'ro';
-    this.constructor.subTemplates['2'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__5__'}));
-    scope = _origScope4;
-    let c6 = [], p6 = {key:6};
-    let vn6 = h('p', p6, c6);
-    c1.push(vn6);
+    this.constructor.subTemplates['2'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__7__'}));
+    scope = _origScope6;
+    let c8 = [], p8 = {key:8};
+    let vn8 = h('p', p8, c8);
+    c1.push(vn8);
     if (scope.iter != null) {
-        c6.push({text: scope.iter});
+        c8.push({text: scope.iter});
     }
     return vn1;
 }"
@@ -1284,7 +1284,7 @@ exports[`other directives with t-component t-set can't alter in t-call body 1`]
     if (scope.iter != null) {
         c2.push({text: scope.iter});
     }
-    let _origScope4 = scope;
+    let _origScope6 = scope;
     scope = Object.create(scope);
     scope.__access_mode__ = 'ro';
     {
@@ -1293,14 +1293,14 @@ exports[`other directives with t-component t-set can't alter in t-call body 1`]
             utils.getScope(scope, 'iter').iter = 'inCall';
             scope[utils.zero] = c__0;
         }
-        this.constructor.subTemplates['2'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__5__'}));
+        this.constructor.subTemplates['2'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__7__'}));
     }
-    scope = _origScope4;
-    let c6 = [], p6 = {key:6};
-    let vn6 = h('p', p6, c6);
-    c1.push(vn6);
+    scope = _origScope6;
+    let c8 = [], p8 = {key:8};
+    let vn8 = h('p', p8, c8);
+    c1.push(vn8);
     if (scope.iter != null) {
-        c6.push({text: scope.iter});
+        c8.push({text: scope.iter});
     }
     return vn1;
 }"
@@ -1455,11 +1455,11 @@ exports[`random stuff/miscellaneous can inject values in tagged templates 1`] =
     let h = this.h;
     let c1 = [], p1 = {key:1};
     let vn1 = h('div', p1, c1);
-    let _origScope4 = scope;
+    let _origScope5 = scope;
     scope = Object.create(scope);
     scope.__access_mode__ = 'ro';
-    this.constructor.subTemplates['3'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__5__'}));
-    scope = _origScope4;
+    this.constructor.subTemplates['3'].call(this, scope, Object.assign({}, extra, {parentNode: c1, parent: utils.getComponent(context), key: '__6__'}));
+    scope = _origScope5;
     return vn1;
 }"
 `;
@@ -1574,15 +1574,15 @@ exports[`t-call handlers are properly bound through a t-call 1`] = `
     // Template name: \\"sub\\"
     let utils = this.constructor.utils;
     let h = this.h;
-    let c1 = extra.parentNode;
+    let c2 = extra.parentNode;
     let key0 = extra.key || \\"\\";
-    let c2 = [], p2 = {key:\`\${key0}_2\`,on:{}};
-    let vn2 = h('p', p2, c2);
-    c1.push(vn2);
-    let k3 = \`click__3__\${key0}__\`;
-    extra.handlers[k3] = extra.handlers[k3] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['update'](e);};
-    p2.on['click'] = extra.handlers[k3];
-    c2.push({text: \`lucas\`});
+    let c3 = [], p3 = {key:\`\${key0}_3\`,on:{}};
+    let vn3 = h('p', p3, c3);
+    c2.push(vn3);
+    let k4 = \`click__4__\${key0}__\`;
+    extra.handlers[k4] = extra.handlers[k4] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['update'](e);};
+    p3.on['click'] = extra.handlers[k4];
+    c3.push({text: \`lucas\`});
 }"
 `;
 
@@ -1593,14 +1593,14 @@ exports[`t-call handlers with arguments are properly bound through a t-call 1`]
     let utils = this.constructor.utils;
     let scope = Object.create(context);
     let h = this.h;
-    let c1 = extra.parentNode;
+    let c2 = extra.parentNode;
     let key0 = extra.key || \\"\\";
-    let c2 = [], p2 = {key:\`\${key0}_2\`,on:{}};
-    let vn2 = h('p', p2, c2);
-    c1.push(vn2);
-    let args3 = [scope['a']];
-    p2.on['click'] = function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['update'](...args3, e);};
-    c2.push({text: \`lucas\`});
+    let c3 = [], p3 = {key:\`\${key0}_3\`,on:{}};
+    let vn3 = h('p', p3, c3);
+    c2.push(vn3);
+    let args4 = [scope['a']];
+    p3.on['click'] = function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['update'](...args4, e);};
+    c3.push({text: \`lucas\`});
 }"
 `;
 
@@ -1613,32 +1613,32 @@ exports[`t-call parent is set within t-call 1`] = `
     let parent = extra.parent;
     let scope = Object.create(context);
     let h = this.h;
-    let c1 = extra.parentNode;
+    let c2 = extra.parentNode;
     let key0 = extra.key || \\"\\";
     // Component 'Child'
-    let k3 = \`__3__\${key0}__\`;
-    let w2 = k3 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[k3]] : false;
-    let props2 = {};
-    if (w2 && w2.__owl__.currentFiber && !w2.__owl__.vnode) {
-        w2.destroy();
-        w2 = false;
+    let k4 = \`__4__\${key0}__\`;
+    let w3 = k4 in parent.__owl__.cmap ? parent.__owl__.children[parent.__owl__.cmap[k4]] : false;
+    let props3 = {};
+    if (w3 && w3.__owl__.currentFiber && !w3.__owl__.vnode) {
+        w3.destroy();
+        w3 = false;
     }
-    if (w2) {
-        w2.__updateProps(props2, extra.fiber, undefined);
-        let pvnode = w2.__owl__.pvnode;
-        c1.push(pvnode);
+    if (w3) {
+        w3.__updateProps(props3, extra.fiber, undefined);
+        let pvnode = w3.__owl__.pvnode;
+        c2.push(pvnode);
     } else {
-        let componentKey2 = \`Child\`;
-        let W2 = context.constructor.components[componentKey2] || QWeb.components[componentKey2]|| scope['Child'];
-        if (!W2) {throw new Error('Cannot find the definition of component \\"' + componentKey2 + '\\"')}
-        w2 = new W2(parent, props2);
-        parent.__owl__.cmap[k3] = w2.__owl__.id;
-        let fiber = w2.__prepare(extra.fiber, undefined, () => { const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
-        let pvnode = h('dummy', {key: k3, hook: {remove() {},destroy(vn) {w2.destroy();}}});
-        c1.push(pvnode);
-        w2.__owl__.pvnode = pvnode;
+        let componentKey3 = \`Child\`;
+        let W3 = context.constructor.components[componentKey3] || QWeb.components[componentKey3]|| scope['Child'];
+        if (!W3) {throw new Error('Cannot find the definition of component \\"' + componentKey3 + '\\"')}
+        w3 = new W3(parent, props3);
+        parent.__owl__.cmap[k4] = w3.__owl__.id;
+        let fiber = w3.__prepare(extra.fiber, undefined, () => { const vnode = fiber.vnode; pvnode.sel = vnode.sel; });
+        let pvnode = h('dummy', {key: k4, hook: {remove() {},destroy(vn) {w3.destroy();}}});
+        c2.push(pvnode);
+        w3.__owl__.pvnode = pvnode;
     }
-    w2.__owl__.parentLastFiberId = extra.fiber.id;
+    w3.__owl__.parentLastFiberId = extra.fiber.id;
 }"
 `;
 

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

@@ -44,23 +44,23 @@ exports[`t-slot directive can define and call slots 2`] = `
 ) {
     // Template name: \\"Dialog\\"
     let h = this.h;
-    let c6 = [], p6 = {key:6};
-    let vn6 = h('div', p6, c6);
-    let c7 = [], p7 = {key:7};
-    let vn7 = h('div', p7, c7);
-    c6.push(vn7);
-    const slot8 = this.constructor.slots[context.__owl__.slotId + '_' + 'header'];
-    if (slot8) {
-        slot8.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c7, parent: extra.parent || context}));
-    }
     let c9 = [], p9 = {key:9};
     let vn9 = h('div', p9, c9);
-    c6.push(vn9);
-    const slot10 = this.constructor.slots[context.__owl__.slotId + '_' + 'footer'];
-    if (slot10) {
-        slot10.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c9, parent: extra.parent || context}));
+    let c10 = [], p10 = {key:10};
+    let vn10 = h('div', p10, c10);
+    c9.push(vn10);
+    const slot11 = this.constructor.slots[context.__owl__.slotId + '_' + 'header'];
+    if (slot11) {
+        slot11.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c10, parent: extra.parent || context}));
     }
-    return vn6;
+    let c12 = [], p12 = {key:12};
+    let vn12 = h('div', p12, c12);
+    c9.push(vn12);
+    const slot13 = this.constructor.slots[context.__owl__.slotId + '_' + 'footer'];
+    if (slot13) {
+        slot13.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c12, parent: extra.parent || context}));
+    }
+    return vn9;
 }"
 `;
 
@@ -69,11 +69,11 @@ exports[`t-slot directive can define and call slots 3`] = `
 ) {
     // Template name: \\"slot_header_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    c1.push(vn4);
-    c4.push({text: \`header\`});
+    let c4 = extra.parentNode;
+    let c5 = [], p5 = {key:5};
+    let vn5 = h('span', p5, c5);
+    c4.push(vn5);
+    c5.push({text: \`header\`});
 }"
 `;
 
@@ -82,11 +82,11 @@ exports[`t-slot directive can define and call slots 4`] = `
 ) {
     // Template name: \\"slot_footer_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c5 = [], p5 = {key:5};
-    let vn5 = h('span', p5, c5);
-    c1.push(vn5);
-    c5.push({text: \`footer\`});
+    let c6 = extra.parentNode;
+    let c7 = [], p7 = {key:7};
+    let vn7 = h('span', p7, c7);
+    c6.push(vn7);
+    c7.push({text: \`footer\`});
 }"
 `;
 
@@ -134,23 +134,23 @@ exports[`t-slot directive can define and call slots using old t-set keyword 2`]
 ) {
     // Template name: \\"__template__1\\"
     let h = this.h;
-    let c6 = [], p6 = {key:6};
-    let vn6 = h('div', p6, c6);
-    let c7 = [], p7 = {key:7};
-    let vn7 = h('div', p7, c7);
-    c6.push(vn7);
-    const slot8 = this.constructor.slots[context.__owl__.slotId + '_' + 'header'];
-    if (slot8) {
-        slot8.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c7, parent: extra.parent || context}));
-    }
     let c9 = [], p9 = {key:9};
     let vn9 = h('div', p9, c9);
-    c6.push(vn9);
-    const slot10 = this.constructor.slots[context.__owl__.slotId + '_' + 'footer'];
-    if (slot10) {
-        slot10.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c9, parent: extra.parent || context}));
+    let c10 = [], p10 = {key:10};
+    let vn10 = h('div', p10, c10);
+    c9.push(vn10);
+    const slot11 = this.constructor.slots[context.__owl__.slotId + '_' + 'header'];
+    if (slot11) {
+        slot11.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c10, parent: extra.parent || context}));
     }
-    return vn6;
+    let c12 = [], p12 = {key:12};
+    let vn12 = h('div', p12, c12);
+    c9.push(vn12);
+    const slot13 = this.constructor.slots[context.__owl__.slotId + '_' + 'footer'];
+    if (slot13) {
+        slot13.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c12, parent: extra.parent || context}));
+    }
+    return vn9;
 }"
 `;
 
@@ -159,11 +159,11 @@ exports[`t-slot directive can define and call slots using old t-set keyword 3`]
 ) {
     // Template name: \\"slot_header_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    c1.push(vn4);
-    c4.push({text: \`header\`});
+    let c4 = extra.parentNode;
+    let c5 = [], p5 = {key:5};
+    let vn5 = h('span', p5, c5);
+    c4.push(vn5);
+    c5.push({text: \`header\`});
 }"
 `;
 
@@ -172,11 +172,11 @@ exports[`t-slot directive can define and call slots using old t-set keyword 4`]
 ) {
     // Template name: \\"slot_footer_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c5 = [], p5 = {key:5};
-    let vn5 = h('span', p5, c5);
-    c1.push(vn5);
-    c5.push({text: \`footer\`});
+    let c6 = extra.parentNode;
+    let c7 = [], p7 = {key:7};
+    let vn7 = h('span', p7, c7);
+    c6.push(vn7);
+    c7.push({text: \`footer\`});
 }"
 `;
 
@@ -185,11 +185,11 @@ exports[`t-slot directive content is the default slot 1`] = `
 ) {
     // Template name: \\"slot_default_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    c1.push(vn4);
-    c4.push({text: \`sts rocks\`});
+    let c4 = extra.parentNode;
+    let c5 = [], p5 = {key:5};
+    let vn5 = h('span', p5, c5);
+    c4.push(vn5);
+    c5.push({text: \`sts rocks\`});
 }"
 `;
 
@@ -215,8 +215,27 @@ exports[`t-slot directive default slot work with text nodes 1`] = `
 ) {
     // Template name: \\"slot_default_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    c1.push({text: \`sts rocks\`});
+    let c4 = extra.parentNode;
+    c4.push({text: \`sts rocks\`});
+}"
+`;
+
+exports[`t-slot directive dynamic t-slot call 1`] = `
+"function anonymous(context, extra
+) {
+    // Template name: \\"__template__1\\"
+    let utils = this.constructor.utils;
+    let scope = Object.create(context);
+    let h = this.h;
+    let c10 = [], p10 = {key:10,on:{}};
+    let vn10 = h('button', p10, c10);
+    extra.handlers['click__11__'] = extra.handlers['click__11__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['toggle'](e);};
+    p10.on['click'] = extra.handlers['click__11__'];
+    const slot12 = this.constructor.slots[context.__owl__.slotId + '_' + (scope['current'].slot)];
+    if (slot12) {
+        slot12.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c10, parent: extra.parent || context}));
+    }
+    return vn10;
 }"
 `;
 
@@ -225,15 +244,15 @@ exports[`t-slot directive multiple roots are allowed in a default slot 1`] = `
 ) {
     // Template name: \\"slot_default_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    c1.push(vn4);
-    c4.push({text: \`sts\`});
+    let c4 = extra.parentNode;
     let c5 = [], p5 = {key:5};
     let vn5 = h('span', p5, c5);
-    c1.push(vn5);
-    c5.push({text: \`rocks\`});
+    c4.push(vn5);
+    c5.push({text: \`sts\`});
+    let c6 = [], p6 = {key:6};
+    let vn6 = h('span', p6, c6);
+    c4.push(vn6);
+    c6.push({text: \`rocks\`});
 }"
 `;
 
@@ -242,15 +261,15 @@ exports[`t-slot directive multiple roots are allowed in a named slot 1`] = `
 ) {
     // Template name: \\"slot_content_template\\"
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    c1.push(vn4);
-    c4.push({text: \`sts\`});
+    let c4 = extra.parentNode;
     let c5 = [], p5 = {key:5};
     let vn5 = h('span', p5, c5);
-    c1.push(vn5);
-    c5.push({text: \`rocks\`});
+    c4.push(vn5);
+    c5.push({text: \`sts\`});
+    let c6 = [], p6 = {key:6};
+    let vn6 = h('span', p6, c6);
+    c4.push(vn6);
+    c6.push({text: \`rocks\`});
 }"
 `;
 
@@ -278,22 +297,22 @@ exports[`t-slot directive refs are properly bound in slots 1`] = `
     let utils = this.constructor.utils;
     context.__owl__.refs = context.__owl__.refs || {};
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c8 = [], p8 = {key:8,on:{}};
-    let vn8 = h('button', p8, c8);
-    c1.push(vn8);
-    extra.handlers['click__9__'] = extra.handlers['click__9__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['doSomething'](e);};
-    p8.on['click'] = extra.handlers['click__9__'];
-    const ref10 = \`myButton\`;
-    p8.hook = {
+    let c8 = extra.parentNode;
+    let c9 = [], p9 = {key:9,on:{}};
+    let vn9 = h('button', p9, c9);
+    c8.push(vn9);
+    extra.handlers['click__10__'] = extra.handlers['click__10__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['doSomething'](e);};
+    p9.on['click'] = extra.handlers['click__10__'];
+    const ref11 = \`myButton\`;
+    p9.hook = {
       create: (_, n) => {
-        context.__owl__.refs[ref10] = n.elm;
+        context.__owl__.refs[ref11] = n.elm;
       },
       destroy: () => {
-        delete context.__owl__.refs[ref10];
+        delete context.__owl__.refs[ref11];
       },
     };
-    c8.push({text: \`do something\`});
+    c9.push({text: \`do something\`});
 }"
 `;
 
@@ -303,13 +322,13 @@ exports[`t-slot directive slots are rendered with proper context 1`] = `
     // Template name: \\"slot_footer_template\\"
     let utils = this.constructor.utils;
     let h = this.h;
-    let c1 = extra.parentNode;
-    let c8 = [], p8 = {key:8,on:{}};
-    let vn8 = h('button', p8, c8);
-    c1.push(vn8);
-    extra.handlers['click__9__'] = extra.handlers['click__9__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['doSomething'](e);};
-    p8.on['click'] = extra.handlers['click__9__'];
-    c8.push({text: \`do something\`});
+    let c8 = extra.parentNode;
+    let c9 = [], p9 = {key:9,on:{}};
+    let vn9 = h('button', p9, c9);
+    c8.push(vn9);
+    extra.handlers['click__10__'] = extra.handlers['click__10__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['doSomething'](e);};
+    p9.on['click'] = extra.handlers['click__10__'];
+    c9.push({text: \`do something\`});
 }"
 `;
 
@@ -319,14 +338,14 @@ exports[`t-slot directive slots are rendered with proper context, part 2 1`] = `
     // Template name: \\"Link\\"
     let scope = Object.create(context);
     let h = this.h;
-    let _11 = scope['props'].to;
-    let c12 = [], p12 = {key:12,attrs:{href: _11}};
-    let vn12 = h('a', p12, c12);
-    const slot13 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
-    if (slot13) {
-        slot13.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c12, parent: extra.parent || context}));
+    let _12 = scope['props'].to;
+    let c13 = [], p13 = {key:13,attrs:{href: _12}};
+    let vn13 = h('a', p13, c13);
+    const slot14 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot14) {
+        slot14.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c13, parent: extra.parent || context}));
     }
-    return vn12;
+    return vn13;
 }"
 `;
 
@@ -401,11 +420,11 @@ exports[`t-slot directive slots are rendered with proper context, part 2 3`] = `
     // Template name: \\"slot_default_template\\"
     let scope = Object.create(context);
     let h = this.h;
-    let c7 = extra.parentNode;
-    c7.push({text: \`User \`});
-    let _10 = scope['user'].name;
-    if (_10 != null) {
-        c7.push({text: _10});
+    let c10 = extra.parentNode;
+    c10.push({text: \`User \`});
+    let _11 = scope['user'].name;
+    if (_11 != null) {
+        c10.push({text: _11});
     }
 }"
 `;
@@ -416,14 +435,14 @@ exports[`t-slot directive slots are rendered with proper context, part 3 1`] = `
     // Template name: \\"Link\\"
     let scope = Object.create(context);
     let h = this.h;
-    let _10 = scope['props'].to;
-    let c11 = [], p11 = {key:11,attrs:{href: _10}};
-    let vn11 = h('a', p11, c11);
-    const slot12 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
-    if (slot12) {
-        slot12.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c11, parent: extra.parent || context}));
+    let _12 = scope['props'].to;
+    let c13 = [], p13 = {key:13,attrs:{href: _12}};
+    let vn13 = h('a', p13, c13);
+    const slot14 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot14) {
+        slot14.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c13, parent: extra.parent || context}));
     }
-    return vn11;
+    return vn13;
 }"
 `;
 
@@ -499,9 +518,10 @@ exports[`t-slot directive slots are rendered with proper context, part 3 3`] = `
     // Template name: \\"slot_default_template\\"
     let scope = Object.create(context);
     let h = this.h;
-    let c7 = extra.parentNode;
-    if (scope.userdescr != null) {
-        c7.push({text: scope.userdescr});
+    let c10 = extra.parentNode;
+    let _11 = scope['userdescr'];
+    if (_11 != null) {
+        c10.push({text: _11});
     }
 }"
 `;
@@ -552,9 +572,10 @@ exports[`t-slot directive slots are rendered with proper context, part 4 2`] = `
     // Template name: \\"slot_default_template\\"
     let scope = Object.create(context);
     let h = this.h;
-    let c1 = extra.parentNode;
-    if (scope.userdescr != null) {
-        c1.push({text: scope.userdescr});
+    let c4 = extra.parentNode;
+    let _5 = scope['userdescr'];
+    if (_5 != null) {
+        c4.push({text: _5});
     }
 }"
 `;
@@ -564,13 +585,13 @@ exports[`t-slot directive t-set t-value in a slot 1`] = `
 ) {
     // Template name: \\"__template__1\\"
     let h = this.h;
-    let c4 = [], p4 = {key:4};
-    let vn4 = h('span', p4, c4);
-    const slot5 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
-    if (slot5) {
-        slot5.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c4, parent: extra.parent || context}));
+    let c5 = [], p5 = {key:5};
+    let vn5 = h('span', p5, c5);
+    const slot6 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot6) {
+        slot6.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c5, parent: extra.parent || context}));
     }
-    return vn4;
+    return vn5;
 }"
 `;
 
@@ -581,12 +602,12 @@ exports[`t-slot directive template can just return a slot 1`] = `
     let utils = this.constructor.utils;
     let result;
     let h = this.h;
-    const slot6 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
-    if (slot6) {
-        let children7= []
+    const slot7 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot7) {
+        let children8= []
         result = {}
-        slot6.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: children7, parent: extra.parent || context}));
-        utils.defineProxy(result, children7[0]);
+        slot7.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: children8, parent: extra.parent || context}));
+        utils.defineProxy(result, children8[0]);
     }
     return result;
 }"

tests/component/async.test.ts

@@ -1405,4 +1405,160 @@ describe("async rendering", () => {
     expect(fixture.innerHTML).toBe("<div>2</div>");
     expect(Widget.prototype.__render).toHaveBeenCalledTimes(2);
   });
+
+  test("components with shouldUpdate=false", async () => {
+    const state = { p: 1, cc: 10 };
+
+    class ChildChild extends Component {
+      static template = xml`
+        <div>
+          child child: <t t-esc="state.cc"/>
+        </div>`;
+      state = state;
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class Child extends Component {
+      static components = { ChildChild };
+      static template = xml`
+        <div>
+          child
+          <ChildChild/>
+        </div>`;
+
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    let parent: any;
+    class Parent extends Component {
+      static components = { Child };
+      static template = xml`
+        <div>
+          parent: <t t-esc="state.p"/>
+          <Child/>
+        </div>`;
+
+      state = state;
+      constructor(a, b) {
+        super(a, b);
+        parent = this;
+      }
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class App extends Component {
+      static components = { Parent };
+      static template = xml`
+        <div>
+          <Parent/>
+        </div>`;
+    }
+
+    var div = document.createElement("div");
+    fixture.appendChild(div);
+
+    const app = new App();
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe(
+      "<div></div><div><div> parent: 1<div> child <div> child child: 10</div></div></div></div>"
+    );
+    app.mount(div);
+
+    // wait for rendering from second mount to go through parent
+    await Promise.resolve();
+    await Promise.resolve();
+    state.cc++;
+    state.p++;
+    parent.render();
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div><div> parent: 2<div> child <div> child child: 11</div></div></div></div></div>"
+    );
+  });
+
+  test("components with shouldUpdate=false, part 2", async () => {
+    const state = { p: 1, cc: 10 };
+    let shouldUpdate = true;
+
+    class ChildChild extends Component {
+      static template = xml`
+        <div>
+          child child: <t t-esc="state.cc"/>
+        </div>`;
+      state = state;
+      shouldUpdate() {
+        return shouldUpdate;
+      }
+    }
+
+    class Child extends Component {
+      static components = { ChildChild };
+      static template = xml`
+        <div>
+          child
+          <ChildChild/>
+        </div>`;
+
+      shouldUpdate() {
+        return shouldUpdate;
+      }
+    }
+
+    let parent: any;
+    class Parent extends Component {
+      static components = { Child };
+      static template = xml`
+        <div>
+          parent: <t t-esc="state.p"/>
+          <Child/>
+        </div>`;
+
+      state = state;
+      constructor(a, b) {
+        super(a, b);
+        parent = this;
+      }
+      shouldUpdate() {
+        return shouldUpdate;
+      }
+    }
+
+    class App extends Component {
+      static components = { Parent };
+      static template = xml`
+        <div>
+          <Parent/>
+        </div>`;
+    }
+
+    const app = new App();
+
+    await app.mount(fixture);
+    expect(fixture.innerHTML).toBe(
+      "<div><div> parent: 1<div> child <div> child child: 10</div></div></div></div>"
+    );
+
+    state.cc++;
+    state.p++;
+    app.render();
+
+    // wait for rendering to go through child
+    await Promise.resolve();
+    await Promise.resolve();
+    await Promise.resolve();
+
+    shouldUpdate = false;
+    parent.render();
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<div><div> parent: 2<div> child <div> child child: 11</div></div></div></div>"
+    );
+  });
 });

tests/component/component.test.ts

@@ -1,4 +1,4 @@
-import { Component, Env } from "../../src/component/component";
+import { Component, Env, mount } from "../../src/component/component";
 import { EventBus } from "../../src/core/event_bus";
 import { useRef, useState } from "../../src/hooks";
 import { QWeb } from "../../src/qweb/qweb";
@@ -69,18 +69,23 @@ describe("basic widget properties", () => {
     class SomeWidget extends Component {
       static template = xml`<div>content</div>`;
     }
-    const widget = new SomeWidget();
-    widget.mount(fixture);
-    await nextTick();
+    await mount(SomeWidget, { target: fixture });
     expect(fixture.innerHTML).toBe("<div>content</div>");
   });
 
+  test("can be mounted with props", async () => {
+    class SomeWidget extends Component {
+      static template = xml`<div><t t-esc="props.content"/></div>`;
+    }
+    await mount(SomeWidget, { target: fixture, props: { content: "foo" } });
+    expect(fixture.innerHTML).toBe("<div>foo</div>");
+  });
+
   test("can be mounted on a documentFragment", async () => {
     class SomeWidget extends Component {
       static template = xml`<div>content</div>`;
     }
-    const widget = new SomeWidget();
-    await widget.mount(document.createDocumentFragment());
+    const widget = await mount(SomeWidget, { target: document.createDocumentFragment() });
     expect(fixture.innerHTML).toBe("");
     await widget.mount(fixture);
     expect(fixture.innerHTML).toBe("<div>content</div>");
@@ -90,10 +95,9 @@ describe("basic widget properties", () => {
     class SomeWidget extends Component {
       static template = xml`<div>content</div>`;
     }
-    const widget = new SomeWidget();
     let error;
     try {
-      await widget.mount(null as any);
+      await mount(SomeWidget, { target: null as any });
     } catch (e) {
       error = e;
     }
@@ -107,10 +111,9 @@ describe("basic widget properties", () => {
     class SomeWidget extends Component {
       static template = xml`<t/>`;
     }
-    const widget = new SomeWidget();
     let error;
     try {
-      await widget.mount(fixture);
+      await mount(SomeWidget, { target: fixture });
     } catch (e) {
       error = e;
     }
@@ -137,8 +140,7 @@ describe("basic widget properties", () => {
       });
     }
 
-    const counter = new Counter();
-    counter.mount(fixture);
+    const counter = await mount(Counter, { target: fixture });
     await nextTick();
     expect(fixture.innerHTML).toBe("<div>0<button>Inc</button></div>");
     const button = (<HTMLElement>counter.el).getElementsByTagName("button")[0];
@@ -156,8 +158,7 @@ describe("basic widget properties", () => {
       static components = { Child };
     }
 
-    const parent = new Parent();
-    await parent.mount(fixture);
+    await mount(Parent, { target: fixture });
     expect(env.qweb.templates[Parent.template].fn.toString()).toMatchSnapshot();
     expect(fixture.innerHTML).toBe("<div><span></span></div>");
   });
@@ -171,9 +172,8 @@ describe("basic widget properties", () => {
       });
     }
 
-    const counter = new Counter();
     const target = document.createElement("div");
-    await counter.mount(target);
+    const counter = await mount(Counter, { target: target });
     expect(target.innerHTML).toBe("<div>0<button>Inc</button></div>");
     const button = (<HTMLElement>counter.el).getElementsByTagName("button")[0];
     button.click();
@@ -188,8 +188,7 @@ describe("basic widget properties", () => {
         <div style="font-weight:bold;" class="some-class">world</div>
       `;
     }
-    const widget = new StyledWidget();
-    await widget.mount(fixture);
+    await mount(StyledWidget, { target: fixture });
     expect(fixture.innerHTML).toBe(`<div style="font-weight:bold;" class="some-class">world</div>`);
   });
 
@@ -212,8 +211,8 @@ describe("basic widget properties", () => {
         steps.push("patched");
       }
     }
-    const widget = new TestW();
-    await widget.mount(fixture);
+    await mount(TestW, { target: fixture });
+
     expect(steps).toEqual(["__render", "mounted"]);
   });
 
@@ -963,6 +962,69 @@ describe("lifecycle hooks", () => {
       "parent:patched",
     ]);
   });
+
+  test("willPatch/patched hook is not called if not mounted in DOM", async () => {
+    const steps: string[] = [];
+
+    class ChildWidget extends Component {
+      static template = xml`<div/>`;
+      constructor(parent, props) {
+        super(parent, props);
+        steps.push("child:constructor");
+      }
+      mounted() {
+        steps.push("child:mounted");
+      }
+      willPatch() {
+        steps.push("child:willPatch");
+      }
+      patched() {
+        steps.push("child:patched");
+      }
+    }
+    class ParentWidget extends Component {
+      static template = xml`
+        <div>
+          <t t-component="child" v="state.n"/>
+        </div>
+      `;
+      static components = { child: ChildWidget };
+      state = useState({ n: 1 });
+      constructor() {
+        super();
+        steps.push("parent:constructor");
+      }
+      mounted() {
+        steps.push("parent:mounted");
+      }
+      willPatch() {
+        steps.push("parent:willPatch");
+      }
+      patched() {
+        steps.push("parent:patched");
+      }
+    }
+
+    const div = document.createElement("div");
+    const widget = new ParentWidget();
+    await widget.mount(div);
+    expect(steps).toEqual(["parent:constructor", "child:constructor"]);
+
+    widget.state.n = 2;
+    await nextTick();
+
+    expect(steps).toEqual(["parent:constructor", "child:constructor"]);
+
+    // then we remount the component in the dom
+    await widget.mount(fixture);
+
+    expect(steps).toEqual([
+      "parent:constructor",
+      "child:constructor",
+      "child:mounted",
+      "parent:mounted",
+    ]);
+  });
 });
 
 describe("destroy method", () => {

tests/component/slots.test.ts

@@ -1,4 +1,4 @@
-import { Component, Env } from "../../src/component/component";
+import { Component, Env, mount } from "../../src/component/component";
 import { QWeb } from "../../src/qweb/qweb";
 import { xml } from "../../src/tags";
 import { useState, useRef } from "../../src/hooks";
@@ -987,4 +987,135 @@ describe("t-slot directive", () => {
 
     expect(fixture.innerHTML).toBe("<div><span><p>sokka</p></span></div>");
   });
+
+  test("named slot inside slot", async () => {
+    class Child extends Component {
+      static template = xml`
+        <div>
+          <t t-slot="brol"/>
+          <t t-slot="default"/>
+        </div>`;
+    }
+    class Parent extends Component {
+      static template = xml`
+        <div>
+          <Child>
+            <t t-set-slot="brol">
+              <p>A<t t-esc="value"/></p>
+            </t>
+            <Child>
+              <t t-set-slot="brol">
+                <p>B<t t-esc="value"/></p>
+              </t>
+            </Child>
+          </Child>
+        </div>`;
+      static components = { Child };
+      value = "blip";
+    }
+    const parent = new Parent();
+    await parent.mount(fixture);
+
+    expect(fixture.innerHTML).toBe("<div><div><p>Ablip</p><div><p>Bblip</p></div></div></div>");
+  });
+
+  test("named slots inside slot, again", async () => {
+    class Child extends Component {
+      static template = xml`
+        <child>
+          <t t-slot="brol1">default1</t>
+          <t t-slot="brol2">default2</t>
+          <t t-slot="default"/>
+        </child>`;
+    }
+    class Parent extends Component {
+      static template = xml`
+        <div>
+          <Child>
+            <t t-set-slot="brol1">
+              <p>A<t t-esc="value"/></p>
+            </t>
+            <Child>
+              <t t-set-slot="brol2">
+                <p>B<t t-esc="value"/></p>
+              </t>
+            </Child>
+          </Child>
+        </div>`;
+      static components = { Child };
+      value = "blip";
+    }
+    const parent = new Parent();
+    await parent.mount(fixture);
+
+    expect(fixture.innerHTML).toBe(
+      "<div><child><p>Ablip</p>default2<child>default1<p>Bblip</p></child></child></div>"
+    );
+  });
+
+  test("named slot inside slot, part 3", async () => {
+    class Child extends Component {
+      static template = xml`
+        <div>
+          <t t-slot="brol"/>
+          <t t-slot="default"/>
+        </div>`;
+    }
+    class Parent extends Component {
+      static template = xml`
+        <div>
+          <Child>
+            <t t-set-slot="brol">
+              <p>A<t t-esc="value"/></p>
+            </t>
+            <Child>
+              <t>
+                <t t-set-slot="brol">
+                  <p>B<t t-esc="value"/></p>
+                </t>
+              </t>
+            </Child>
+          </Child>
+        </div>`;
+      static components = { Child };
+      value = "blip";
+    }
+    const parent = new Parent();
+    await parent.mount(fixture);
+
+    expect(fixture.innerHTML).toBe("<div><div><p>Ablip</p><div><p>Bblip</p></div></div></div>");
+  });
+
+  test("dynamic t-slot call", async () => {
+    class Toggler extends Component {
+      static template = xml`<button t-on-click="toggle"><t t-slot="{{current.slot}}"/></button>`;
+      current = useState({ slot: "slot1" });
+      toggle() {
+        this.current.slot = this.current.slot === "slot1" ? "slot2" : "slot1";
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`
+        <div>
+          <Toggler>
+            <t t-set-slot="slot1"><p>slot1</p><span>content</span></t>
+            <t t-set-slot="slot2"><h1>slot2</h1></t>
+          </Toggler>
+        </div>`;
+      static components = { Toggler };
+    }
+    await mount(Parent, { target: fixture });
+    expect(fixture.innerHTML).toBe("<div><button><p>slot1</p><span>content</span></button></div>");
+
+    fixture.querySelector<HTMLElement>("button")!.click();
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><button><h1>slot2</h1></button></div>");
+
+    fixture.querySelector<HTMLElement>("button")!.click();
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><button><p>slot1</p><span>content</span></button></div>");
+
+    expect(env.qweb.templates[Toggler.template].fn.toString()).toMatchSnapshot();
+  });
 });

tests/component/un_mounting.test.ts

@@ -1,4 +1,4 @@
-import { Component, Env } from "../../src/component/component";
+import { Component, Env, mount } from "../../src/component/component";
 import { useState } from "../../src/hooks";
 import { xml } from "../../src/tags";
 import { makeDeferred, makeTestEnv, makeTestFixture, nextTick, nextMicroTick } from "../helpers";
@@ -37,8 +37,7 @@ describe("mount targets", () => {
     div.innerHTML = `<p>pre-existing</p>`;
     fixture.appendChild(div);
 
-    const app = new App();
-    await app.mount(div, { position: "self" });
+    const app = await mount(App, { target: div, position: "self" });
 
     expect(fixture.innerHTML).toBe(
       `<div class="arbitrary custom"><p>pre-existing</p>app<p>another tag</p></div>`
@@ -66,10 +65,9 @@ describe("mount targets", () => {
     const div = document.createElement("div");
     fixture.appendChild(div);
 
-    const app = new App();
     let error;
     try {
-      await app.mount(div, { position: "self" });
+      await mount(App, { target: div, position: "self" });
     } catch (e) {
       error = e;
     }
@@ -84,8 +82,7 @@ describe("mount targets", () => {
     const span = document.createElement("span");
     fixture.appendChild(span);
 
-    const app = new App();
-    await app.mount(fixture, { position: "first-child" });
+    await mount(App, { target: fixture, position: "first-child" });
     expect(fixture.innerHTML).toBe("<div>app</div><span></span>");
   });
 
@@ -96,8 +93,7 @@ describe("mount targets", () => {
     const span = document.createElement("span");
     fixture.appendChild(span);
 
-    const app = new App();
-    await app.mount(fixture, { position: "last-child" });
+    await mount(App, { target: fixture, position: "last-child" });
     expect(fixture.innerHTML).toBe("<span></span><div>app</div>");
   });
 
@@ -108,8 +104,7 @@ describe("mount targets", () => {
     const span = document.createElement("span");
     fixture.appendChild(span);
 
-    const app = new App();
-    await app.mount(fixture);
+    await mount(App, { target: fixture });
     expect(fixture.innerHTML).toBe("<span></span><div>app</div>");
   });
 });
@@ -133,8 +128,7 @@ describe("unmounting and remounting", () => {
       }
     }
 
-    const w = new MyWidget();
-    await w.mount(fixture);
+    const w = await mount(MyWidget, { target: fixture });
     expect(fixture.innerHTML).toBe("<div>Hey</div>");
     expect(steps).toEqual(["willstart", "mounted"]);
 
@@ -162,8 +156,7 @@ describe("unmounting and remounting", () => {
       }
     }
 
-    const w = new MyWidget();
-    await w.mount(fixture);
+    const w = await mount(MyWidget, { target: fixture });
     await w.mount(fixture);
     expect(fixture.innerHTML).toBe("<div>Hey</div>");
     expect(steps).toEqual(["willstart", "mounted"]);
@@ -203,8 +196,7 @@ describe("unmounting and remounting", () => {
       state = useState({ val: 1, flag: true });
     }
 
-    const widget = new Parent();
-    await widget.mount(fixture);
+    const widget = await mount(Parent, { target: fixture });
     expect(steps).toEqual(["render"]);
     expect(fixture.innerHTML).toBe("<div><span>12</span></div>");
     widget.state.flag = false;
@@ -331,6 +323,54 @@ describe("unmounting and remounting", () => {
     expect(steps).toEqual([2, 2, 3]);
   });
 
+  test("change state and render while mounted in detached dom", async () => {
+    class App extends Component {
+      static template = xml`<div><t t-esc="state.val"/></div>`;
+      state = useState({ val: 1 });
+    }
+
+    const detachedDiv = document.createElement("div");
+    const app = await mount(App, { target: detachedDiv });
+
+    expect(detachedDiv.innerHTML).toBe("<div>1</div>");
+    app.state.val = 2;
+    await nextTick();
+    expect(detachedDiv.innerHTML).toBe("<div>2</div>");
+  });
+
+  test("change state and render while not mounted ", async () => {
+    class App extends Component {
+      static template = xml`<div><t t-esc="state.val"/></div>`;
+      state = useState({ val: 1 });
+    }
+
+    const app = new App(null);
+
+    app.state.val = 2; // will call the render method (before being mounted)
+    await nextTick();
+
+    await app.mount(fixture);
+
+    expect(fixture.innerHTML).toBe("<div>2</div>");
+  });
+
+  test("destroy and change state after mounted in detached dom", async () => {
+    class App extends Component {
+      static template = xml`<div><t t-esc="state.val"/></div>`;
+      state = useState({ val: 1 });
+    }
+
+    const detachedDiv = document.createElement("div");
+    const app = await mount(App, { target: detachedDiv });
+
+    expect(detachedDiv.innerHTML).toBe("<div>1</div>");
+
+    app.destroy();
+    app.state.val = 2;
+    await nextTick();
+    expect(detachedDiv.innerHTML).toBe("");
+  });
+
   test("change state while component is unmounted", async () => {
     let child;
     class Child extends Component {
@@ -608,4 +648,51 @@ describe("unmounting and remounting", () => {
     await parent.render();
     expect(fixture.textContent).toBe("fixedsome text");
   });
+
+  test("remounting component tree where a component implement shouldupdate", async () => {
+    let state: any;
+    const steps = [];
+    class Child extends Component {
+      static template = xml`<div><t t-esc="state.word"/><t t-esc="props.name"/></div>`;
+
+      state = useState({ word: "hello" });
+
+      constructor(parent, props) {
+        super(parent, props);
+        state = this.state;
+      }
+      patched() {
+        steps.push("patched");
+      }
+      mounted() {
+        steps.push("mounted");
+      }
+      willUnmount() {
+        steps.push("willUnmount");
+      }
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`<div><Child name="state.name"/></div>`;
+      static components = { Child };
+      state = useState({ name: "World" });
+    }
+
+    const parent = await mount(Parent, { target: fixture });
+    expect(fixture.innerHTML).toBe("<div><div>helloWorld</div></div>");
+
+    parent.unmount();
+    expect(fixture.innerHTML).toBe("");
+    await parent.mount(fixture);
+    expect(fixture.innerHTML).toBe("<div><div>helloWorld</div></div>");
+
+    state.word = "test";
+
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><div>testWorld</div></div>");
+    expect(steps).toEqual(["mounted", "willUnmount", "mounted", "patched"]);
+  });
 });

tests/context.test.ts

@@ -289,7 +289,26 @@ describe("Context", () => {
     expect(testContext.subscriptions.update.length).toBe(0);
   });
 
-  test("concurrent renderings", async () => {
+  test.skip("concurrent renderings", async () => {
+    /**
+     * Note: this test is interesting, but sadly just an incomplete attempt at
+     * protecting users against themselves.  With the context API, it is not
+     * possible for the framework to protect completely against crashes.  Maybe
+     * like in this case, when a component is in a simple hierarchy where all
+     * renderings come from the context changes, but in a real case, where some
+     * code can trigger a rendering independently, it is insufficient.
+     *
+     * The main problem is that the sub component depends on some external state,
+     * which may be modified, and then incompatible with the component actual
+     * state (for example, if the sub component has an id key related to some
+     * object that has been removed from the context).
+     *
+     * For now, sadly, the only solution is that components that depends on external
+     * state should guarantee their own integrity themselves. Then maybe this
+     * could be solved at the level of a state management solution that has a
+     * more advanced API, to let components determine if they should be updated
+     * or not (so, something slightly more advanced that the useStore hook).
+     */
     const testContext = new Context({ x: { n: 1 }, key: "x" });
     const def = makeDeferred();
     let stateC;

tests/helpers.ts

@@ -37,8 +37,13 @@ export function nextMicroTick(): Promise<void> {
 }
 
 export async function nextTick(): Promise<void> {
-  await new Promise((resolve) => scheduler.requestAnimationFrame(resolve));
   await new Promise((resolve) => setTimeout(resolve));
+  await new Promise((resolve) => scheduler.requestAnimationFrame(resolve));
+}
+
+export async function nextFrame(): Promise<void> {
+  await new Promise((resolve) => scheduler.requestAnimationFrame(resolve));
+  await new Promise((resolve) => scheduler.requestAnimationFrame(resolve));
 }
 
 export function makeTestFixture() {
@@ -127,7 +132,7 @@ export function renderToString(
 // 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 = QWeb.utils.nextFrame;
+let _nextFrame = QWeb.utils.nextFrame;
 export function patchNextFrame(f: Function) {
   QWeb.utils.nextFrame = (cb: () => void) => {
     setTimeout(() => f(cb));
@@ -135,7 +140,7 @@ export function patchNextFrame(f: Function) {
 }
 
 export function unpatchNextFrame() {
-  QWeb.utils.nextFrame = nextFrame;
+  QWeb.utils.nextFrame = _nextFrame;
 }
 
 export async function editInput(input: HTMLInputElement | HTMLTextAreaElement, value: string) {

tests/hooks.test.ts

@@ -9,8 +9,10 @@ import {
   onWillPatch,
   onWillStart,
   onWillUpdateProps,
+  useEnv,
   useSubEnv,
   useExternalListener,
+  useComponent,
 } from "../src/hooks";
 import { xml } from "../src/tags";
 
@@ -520,6 +522,19 @@ describe("hooks", () => {
     });
   });
 
+  test("can use useEnv", async () => {
+    expect.assertions(1);
+    class TestComponent extends Component {
+      static template = xml`<div><t t-esc="env.val"/></div>`;
+      constructor() {
+        super();
+        expect(useEnv()).toBe(env);
+      }
+    }
+    const component = new TestComponent();
+    await component.mount(fixture);
+  });
+
   test("can use sub env", async () => {
     class TestComponent extends Component {
       static template = xml`<div><t t-esc="env.val"/></div>`;
@@ -535,6 +550,19 @@ describe("hooks", () => {
     expect(component.env).toHaveProperty("val");
   });
 
+  test("can use useComponent", async () => {
+    expect.assertions(1);
+    class TestComponent extends Component {
+      static template = xml`<div></div>`;
+      constructor() {
+        super();
+        expect(useComponent()).toBe(this);
+      }
+    }
+    const component = new TestComponent();
+    await component.mount(fixture);
+  });
+
   test("parent and child env", async () => {
     class Child extends Component {
       static template = xml`<div><t t-esc="env.val"/></div>`;

tests/qweb/qweb.test.ts

@@ -238,6 +238,13 @@ describe("t-raw", () => {
       "<span><span>hello</span><ok>world</ok></span>"
     );
   });
+
+  test("t-raw with comment", () => {
+    qweb.addTemplate("test", `<span><t t-raw="var"/></span>`);
+    expect(renderToString(qweb, "test", { var: "<p>text<!-- top secret --></p>" })).toBe(
+      "<span><p>text<!-- top secret --></p></span>"
+    );
+  });
 });
 
 describe("t-set", () => {
@@ -1088,6 +1095,26 @@ describe("t-call (template calling", () => {
     const expected = "<div><p>yip yip</p></div>";
     expect(renderToString(qweb, "main")).toBe(expected);
   });
+
+  test("t-call with body content as root of a template", () => {
+    qweb.addTemplate("antony", `<foo><t t-raw="0"/></foo>`);
+    qweb.addTemplate("main", `<t><t t-call="antony"><p>antony</p></t></t>`);
+    const expected = "<foo><p>antony</p></foo>";
+    expect(renderToString(qweb, "main")).toBe(expected);
+  });
+
+  test("dynamic t-call", () => {
+    qweb.addTemplate("foo", `<foo><t t-esc="val"/></foo>`);
+    qweb.addTemplate("bar", `<bar><t t-esc="val"/></bar>`);
+    qweb.addTemplate("main", `<div><t t-call="{{template}}"/></div>`);
+    const expected = "<div><foo>foo</foo></div>";
+    expect(renderToString(qweb, "main", { template: "foo", val: "foo" })).toBe(expected);
+    const expected2 = "<div><bar>quux</bar></div>";
+    expect(renderToString(qweb, "main", { template: "bar", val: "quux" })).toBe(expected2);
+    // duplicate call because there was a specific bug with some id that was
+    // incremented each rendering.
+    expect(renderToString(qweb, "main", { template: "bar", val: "quux" })).toBe(expected2);
+  });
 });
 
 describe("foreach", () => {
@@ -2127,6 +2154,17 @@ describe("translation support", () => {
       '<div><p label="mot">mot</p><p title="mot">mot</p><p placeholder="mot">mot</p><p alt="mot">mot</p><p something="word">mot</p></div>'
     );
   });
+
+  test("translation is done on the trimmed text, with extra spaces readded after", () => {
+    const translations = {
+      word: "mot",
+    };
+    const translateFn = jest.fn((expr) => translations[expr] || expr);
+    const qweb = new QWeb({ translateFn });
+    qweb.addTemplate("test", "<div> word </div>");
+    expect(renderToString(qweb, "test")).toBe("<div> mot </div>");
+    expect(translateFn).toHaveBeenCalledWith("word");
+  });
 });
 
 describe("t-key tests", () => {

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

@@ -7,16 +7,16 @@ exports[`Link component can render simple cases 1`] = `
     let utils = this.constructor.utils;
     let scope = Object.create(context);
     let h = this.h;
-    let _4 = utils.toObj({'router-link-active':scope['isActive']});
-    let _5 = scope['href'];
-    let c6 = [], p6 = {key:6,attrs:{href: _5},class:_4,on:{}};
-    let vn6 = h('a', p6, c6);
-    extra.handlers['click__7__'] = extra.handlers['click__7__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['navigate'](e);};
-    p6.on['click'] = extra.handlers['click__7__'];
-    const slot8 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
-    if (slot8) {
-        slot8.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c6, parent: extra.parent || context}));
+    let _5 = utils.toObj({'router-link-active':scope['isActive']});
+    let _6 = scope['href'];
+    let c7 = [], p7 = {key:7,attrs:{href: _6},class:_5,on:{}};
+    let vn7 = h('a', p7, c7);
+    extra.handlers['click__8__'] = extra.handlers['click__8__'] || function (e) {if (!context.__owl__.isMounted){return}utils.getComponent(context)['navigate'](e);};
+    p7.on['click'] = extra.handlers['click__8__'];
+    const slot9 = this.constructor.slots[context.__owl__.slotId + '_' + 'default'];
+    if (slot9) {
+        slot9.call(this, context.__owl__.scope, Object.assign({}, extra, {parentNode: c7, parent: extra.parent || context}));
     }
-    return vn6;
+    return vn7;
 }"
 `;

tests/store_hooks.test.ts

@@ -1,4 +1,4 @@
-import { Component, Env } from "../src/component/component";
+import { Component, Env, mount } from "../src/component/component";
 import { Store, useStore, useDispatch, useGetters, EnvWithStore } from "../src/store";
 import { useState } from "../src/hooks";
 import { xml } from "../src/tags";
@@ -571,12 +571,12 @@ describe("connecting a component to store", () => {
     app.state.beerId = 2;
     await nextTick();
     expect(fixture.innerHTML).toBe("<div><span>kwak</span></div>");
-    expect(counter).toBe(1);
+    expect(counter).toBe(0);
 
     store.dispatch("renameBeer", { id: 2, name: "orval" });
     await nextTick();
     expect(fixture.innerHTML).toBe("<div><span>orval</span></div>");
-    expect(counter).toBe(2);
+    expect(counter).toBe(1);
   });
 
   test("connected component is properly cleaned up on destroy", async () => {
@@ -1241,4 +1241,162 @@ describe("various scenarios", () => {
     await nextTick();
     expect(fixture.innerHTML).toMatchSnapshot();
   });
+
+  test("component with store, useState and shouldUpdate=false", async () => {
+    let state: any;
+
+    const store = new Store({ state: { rev: 0 } });
+
+    class Child extends Component {
+      static template = xml`<div><t t-esc="state.word"/><t t-esc="props.name"/></div>`;
+
+      state = useState({ word: "hello" });
+
+      constructor(parent, props) {
+        super(parent, props);
+        state = this.state;
+        useStore((props) => {
+          return 1;
+        });
+      }
+
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`<div><Child name="state.name"/></div>`;
+      static components = { Child };
+
+      state = useState({ name: "World" });
+
+      constructor(parent, props) {
+        super(parent, props);
+        useStore((props) => store.state.rev);
+      }
+    }
+    (env as any).store = store;
+
+    await mount(Parent, { target: fixture, env });
+    expect(fixture.innerHTML).toBe("<div><div>helloWorld</div></div>");
+
+    store.state.rev++;
+    // this is the key to the bug, it makes Parent be in "render" state but not
+    // yet rendered while the change of state happens
+    await Promise.resolve();
+    state.word = "test";
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><div>testWorld</div></div>");
+  });
+
+  test("component with store, useState, shouldUpdate=false and child with shouldupdate false", async () => {
+    let state: any;
+
+    const store = new Store({ state: { rev: 0 } });
+
+    class ChildChild extends Component {
+      static template = xml`<div><t t-esc="props.value"/></div>`;
+
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class Child extends Component {
+      static template = xml`<div><t t-esc="state.word"/><t t-esc="props.name"/><ChildChild value="state.value"/></div>`;
+      static components = { ChildChild };
+      state = useState({ word: "hello", value: 3 });
+
+      constructor(parent, props) {
+        super(parent, props);
+        state = this.state;
+        useStore((props) => {
+          return 1;
+        });
+      }
+
+      shouldUpdate() {
+        return false;
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`<div><Child name="state.name"/></div>`;
+      static components = { Child };
+
+      state = useState({ name: "World" });
+      constructor(parent, props) {
+        super(parent, props);
+        useStore((props) => store.state.rev);
+      }
+    }
+    (env as any).store = store;
+
+    await mount(Parent, { target: fixture, env });
+    expect(fixture.innerHTML).toBe("<div><div>helloWorld<div>3</div></div></div>");
+
+    store.state.rev++;
+    // this is the key to the bug, it makes Parent be in "render" state but not
+    // yet rendered while the change of state happens
+    await Promise.resolve();
+    state.word = "test";
+    state.value = 44;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><div>testWorld<div>3</div></div></div>");
+  });
+
+  test("parent/children with store, parent is remounted", async () => {
+    const store = new Store({ state: { a: 1, b: 1 } });
+
+    class Child extends Component {
+      static template = xml`<div><t t-esc="a"/></div>`;
+      a: any;
+      constructor(parent, props) {
+        super(parent, props);
+        this.a = useStore(
+          (state, props) => {
+            return state.a;
+          },
+          {
+            onUpdate: (a) => {
+              this.a = a;
+            },
+          }
+        );
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`
+        <div>
+          parent: <t t-esc="b"/>
+          <Child/>
+        </div>`;
+      static components = { Child };
+
+      b: any;
+      constructor(parent, props) {
+        super(parent, props);
+        this.b = useStore((state, props) => {
+          return state.b;
+        });
+      }
+    }
+    (env as any).store = store;
+
+    const div = document.createElement("div");
+    fixture.appendChild(div);
+
+    // initial mounting
+    const parent = await mount(Parent, { target: fixture, env });
+    expect(fixture.innerHTML).toBe("<div></div><div> parent: 1<div>1</div></div>");
+
+    // remounting component, then immediately update store.state
+    parent.mount(div);
+    store.state.a++;
+
+    await nextTick();
+    expect(fixture.innerHTML).toBe("<div><div> parent: 1<div>2</div></div></div>");
+  });
 });

tests/tooling/debug_script_3.test.ts

@@ -8,7 +8,7 @@ import * as owl from "../../src/index";
 
 import { Component, Env } from "../../src/component/component";
 import { xml } from "../../src/tags";
-import { makeTestFixture, makeTestEnv } from "../helpers";
+import { makeTestFixture, makeTestEnv, nextTick } from "../helpers";
 
 let fixture: HTMLElement = makeTestFixture();
 let env: Env = makeTestEnv();
@@ -31,6 +31,7 @@ test("log a specific message for render method calls if component is not mounted
   parent.unmount();
   parent.state.value = 2;
 
+  await nextTick();
   expect(steps).toEqual([
     "[OWL_DEBUG] Parent<id=1> constructor, props={}",
     "[OWL_DEBUG] Parent<id=1> mount",
@@ -40,7 +41,10 @@ test("log a specific message for render method calls if component is not mounted
     "[OWL_DEBUG] Parent<id=1> mounted",
     "[OWL_DEBUG] scheduler: stop running tasks queue",
     "[OWL_DEBUG] Parent<id=1> willUnmount",
-    "[OWL_DEBUG] Parent<id=1> render (warning: component is not mounted, this render has no effect)",
+    "[OWL_DEBUG] Parent<id=1> render (warning: component is not mounted)",
+    "[OWL_DEBUG] scheduler: start running tasks queue",
+    "[OWL_DEBUG] Parent<id=1> rendering template",
+    "[OWL_DEBUG] scheduler: stop running tasks queue",
   ]);
   console.log = log;
 });

tools/debug.js

@@ -102,7 +102,7 @@
       const __owl__ = component.__owl__;
       let msg = `render`;
       if (!__owl__.isMounted && !__owl__.currentFiber) {
-        msg += ` (warning: component is not mounted, this render has no effect)`;
+        msg += ` (warning: component is not mounted)`;
       }
       log(msg);
       return render(...args);

tools/playground/app.js

@@ -1,5 +1,6 @@
 import { SAMPLES } from "./samples.js";
-const { useState, useRef, onMounted, onWillUnmount } = owl.hooks;
+const { mount, hooks } = owl;
+const { useState, useRef, onMounted, onWillUnmount } = hooks;
 //------------------------------------------------------------------------------
 // Constants, helpers, utils
 //------------------------------------------------------------------------------
@@ -419,9 +420,8 @@ async function start() {
     owl.utils.whenReady()
   ]);
   const qweb = new owl.QWeb({ templates });
-  owl.Component.env = { qweb };
-  const app = new App();
-  app.mount(document.body);
+  const env = { qweb };
+  await mount(App, {target: document.body, env});
 }
 
 start();

tools/playground/samples.js

@@ -1,5 +1,5 @@
 const COMPONENTS = `// In this example, we show how components can be defined and created.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 
 class Greeter extends Component {
     constructor() {
@@ -22,8 +22,7 @@ class App extends Component {
 App.components = { Greeter };
 
 // Application setup
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const COMPONENTS_XML = `<templates>
@@ -50,7 +49,7 @@ const COMPONENTS_CSS = `.greeter {
 
 const ANIMATION = `// The goal of this component is to see how the t-transition directive can be
 // used to generate simple transition effects.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 
 class Counter extends Component {
     constructor() {
@@ -80,8 +79,7 @@ class App extends Component {
 }
 App.components = { Counter };
 
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const ANIMATION_XML = `<templates>
@@ -193,7 +191,7 @@ const LIFECYCLE_DEMO = `// This example shows all the possible lifecycle hooks
 // methods in the console.  Try modifying its state by clicking on it, or by
 // clicking on the two main buttons, and look into the console to see what
 // happens.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 
 class DemoComponent extends Component {
     constructor() {
@@ -240,8 +238,7 @@ class App extends Component {
 }
 App.components = { DemoComponent };
 
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const LIFECYCLE_DEMO_XML = `<templates>
@@ -273,7 +270,8 @@ const LIFECYCLE_CSS = `button {
 }`;
 
 const HOOKS_DEMO = `// In this example, we show how hooks can be used or defined.
-const {useState, onMounted, onWillUnmount} = owl.hooks;
+const { hooks, mount } = owl;
+const {useState, onMounted, onWillUnmount} = hooks;
 
 // We define here a custom behaviour: this hook tracks the state of the mouse
 // position
@@ -312,8 +310,7 @@ class App extends owl.Component {
 }
 
 // Application setup
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const HOOKS_DEMO_XML = `<templates>
@@ -332,7 +329,7 @@ const HOOKS_CSS = `button {
 
 const CONTEXT_JS = `// In this example, we show how components can use the Context and 'useContext'
 // hook to share information between them.
-const { Component, Context } = owl;
+const { Component, Context, mount } = owl;
 const { useContext } = owl.hooks;
 
 class ToolbarButton extends Component {
@@ -367,8 +364,7 @@ const themeContext = new Context({
 });
 // Add the themeContext the environment to make it available to all components
 App.env.themeContext = themeContext;
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const CONTEXT_XML = `<templates>
@@ -395,7 +391,7 @@ const TODO_APP_STORE = `// This example is an implementation of the TodoList app
 //
 // In this implementation, we use the owl Store class to manage the state.  It
 // is very similar to the VueX store.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 const { useRef, useStore, useDispatch, onPatched, onMounted } = owl.hooks;
 
 //------------------------------------------------------------------------------
@@ -568,8 +564,7 @@ function makeStore() {
 }
 
 TodoApp.env.store = makeStore();
-const app = new TodoApp();
-app.mount(document.body);
+mount(TodoApp, { target: document.body });
 `;
 
 const TODO_APP_STORE_XML = `<templates>
@@ -1060,8 +1055,7 @@ function setupResponsivePlugin(env) {
 //------------------------------------------------------------------------------
 setupResponsivePlugin(App.env);
 
-const app = new App();
-app.mount(document.body);
+owl.mount(App, { target: document.body });
 `;
 
 const RESPONSIVE_XML = `<templates>
@@ -1173,7 +1167,7 @@ const SLOTS = `// We show here how slots can be used to create generic component
 //
 // Note that the t-on-click event, defined in the App template, is executed in
 // the context of the App component, even though it is inside the Card component
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 
 class Card extends Component {
     constructor() {
@@ -1211,8 +1205,8 @@ class App extends Component {
 App.components = {Card, Counter};
 
 // Application setup
-const app = new App();
-app.mount(document.body);`;
+mount(App, { target: document.body });
+`;
 
 const SLOTS_XML = `<templates>
   <div t-name="Card" class="card" t-att-class="state.showContent ? 'full' : 'small'">
@@ -1298,7 +1292,7 @@ const ASYNC_COMPONENTS = `// This example will not work if your browser does not
 // However, we don't want renderings of the other sub component to be delayed
 // because of the slow component. We use the AsyncRoot component for this
 // purpose. Try removing it to see the difference.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 const { AsyncRoot } = owl.misc;
 
 class SlowComponent extends Component {
@@ -1329,8 +1323,7 @@ class App extends Component {
 }
 App.components = {SlowComponent, NotificationList, AsyncRoot};
 
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const ASYNC_COMPONENTS_XML = `<templates>
@@ -1385,7 +1378,7 @@ const FORM = `// This example illustrate how the t-model directive can be used t
 // data between html inputs (and select/textareas) and the state of a component.
 // Note that there are two controls with t-model="color": they are totally
 // synchronized.
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 
 class Form extends Component {
     constructor() {
@@ -1401,8 +1394,7 @@ class Form extends Component {
 }
 
 // Application setup
-const form = new Form();
-form.mount(document.body);
+mount(Form, { target: document.body });
 `;
 
 const FORM_XML = `<templates>
@@ -1448,7 +1440,7 @@ const PORTAL_COMPONENTS = `
 // This shows the expected use case of Portal
 // which is to implement something similar
 // to bootstrap modal
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 const { Portal } = owl.misc;
 
 class Modal extends Component {}
@@ -1470,8 +1462,7 @@ class App extends Component {
 App.components = { Dialog , Interstellar };
 
 // Application setup
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const PORTAL_XML = `
@@ -1559,7 +1550,7 @@ const WMS = `// This example is slightly more complex than usual. We demonstrate
 // - minimal width/height
 // - better heuristic for initial window position
 // - ...
-const { Component, useState } = owl;
+const { Component, useState, mount } = owl;
 const { useRef } = owl.hooks;
 
 class HelloWorld extends Component {}
@@ -1699,8 +1690,7 @@ const windows = [
 ];
 
 App.env.windows = windows;
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 const WMS_XML = `<templates>
@@ -1818,7 +1808,7 @@ const SFC = `// This example illustrates how Owl enables single file components,
 // Note that this example has no external xml or css file, everything is
 // contained in a single js file.
 
-const { Component, useState, tags } = owl;
+const { Component, useState, tags, mount } = owl;
 const { xml, css } = tags;
 
 // Counter component
@@ -1850,8 +1840,7 @@ App.template = APP_TEMPLATE;
 App.components = { Counter };
 
 // Application setup
-const app = new App();
-app.mount(document.body);
+mount(App, { target: document.body });
 `;
 
 export const SAMPLES = [

tools/release.js

@@ -3,10 +3,9 @@ const readline = require("readline");
 const fs = require("fs");
 const exec = require("child_process").exec;
 const chalk = require("chalk");
-const GitHub = require("github-api");
 
 const REL_NOTES_FILE = `release-notes.md`;
-const STEPS = 10;
+const STEPS = 8;
 
 const rl = readline.createInterface({
   input: process.stdin,
@@ -28,7 +27,8 @@ async function startRelease() {
   // ---------------------------------------------------------------------------
   log(`Step 1/${STEPS}: collecting info...`);
   const current = package.version;
-  const next = await ask("Next version: ");
+  let next = await ask("Next version: ");
+  if (next[0] === 'v') next = next.substring(1);
   let file = await ask(`Release notes (${REL_NOTES_FILE}): `);
   file = file || REL_NOTES_FILE;
   let content;
@@ -39,11 +39,12 @@ async function startRelease() {
     log("Cannot find release notes... Aborting");
     return;
   }
-
-  // Todo: add playground update feature
-  // let shouldUpdateStr = await ask("Update Playground? (y/n)");
-  // const shouldUpdatePlayground = shouldUpdateStr === "y";
-  const token = await ask("Github token: ");
+  let shouldBeDraft = await ask(`Should be a draft [y/n] ? (n)`);
+  let draft = ""
+  if (shouldBeDraft.toLowerCase() === 'y')
+  {
+    draft = "--draft";
+  }
 
   // ---------------------------------------------------------------------------
   log(`Step 2/${STEPS}: running tests...`);
@@ -52,14 +53,12 @@ async function startRelease() {
     log("Test suite does not pass. Aborting.");
     return;
   }
-  await ask("Ready for next step...");
 
   // ---------------------------------------------------------------------------
   log(`Step 3/${STEPS}: updating package.json, readme.md and roadmap.md...`);
   await replaceInFile("./package.json", current, next);
   await replaceInFile("./README.md", current, next);
   await replaceInFile("./roadmap.md", current, next);
-  await ask("Ready for next step...");
 
   // ---------------------------------------------------------------------------
   log(`Step 4/${STEPS}: creating git commit...`);
@@ -68,61 +67,40 @@ async function startRelease() {
     log("Git commit failed. Aborting.");
     return;
   }
-  await ask("Ready for next step...");
 
-  // -------------------j--------------------------------------------------------
-  log(`Step 5/${STEPS}: building owl (iife version)...`);
+  // ----------------------------------------------------------------------------
+  log(`Step 5/${STEPS}: building owl...`);
+  await execCommand("npm run prettier");
   const buildResult = await execCommand("npm run build");
   if (buildResult !== 0) {
     log("Build failed. Aborting.");
     return;
   }
-  await ask("Ready for next step...");
 
   // ---------------------------------------------------------------------------
-  log(`Step 6/${STEPS}: minifying owl...`);
-  const minifyResult = await execCommand("npm run minify");
-  if (minifyResult !== 0) {
-    log("Minify failed. Aborting.");
-    return;
-  }
-  await ask("Ready for next step...");
-
-  // ---------------------------------------------------------------------------
-  log(`Step 7/${STEPS}: pushing on github...`);
+  log(`Step 6/${STEPS}: pushing on github...`);
   const pushResult = await execCommand("git push");
   if (pushResult !== 0) {
     log("git push failed. Aborting.");
     return;
   }
-  await ask("Ready for next step...");
 
   // ---------------------------------------------------------------------------
-  log(`Step 8/${STEPS}: publishing release notes on github...`);
-  const options = {
-    tag_name: `v${next}`,
-    name: `v${next}`,
-    body: content,
-    draft: true // todo: remove this someday
-  };
-  const result = await createRelease(token, options);
-  await ask("Ready for next step...");
 
-  // ---------------------------------------------------------------------------
-  log(`Step 9/${STEPS}: adding assets to release...`);
-  await ask("Please add owl.js and owl.min.js to draft release, then confirm");
-  // todo: do this with curl
-  // curl \
-  //   -H "Authorization: token $GITHUB_TOKEN" \
-  //   -H "Content-Type: $(file -b --mime-type $FILE)" \
-  //   --data-binary @$FILE \
-  //   "https://uploads.github.com/repos/hubot/singularity/releases/123/assets?name=$(basename $FILE)"
+  log(`Step 7/${STEPS}: Creating the release...`);
+  const relaseResult = await execCommand(`gh release create v${next} dist/*.js ${draft} -F release-notes.md`);
+  if (relaseResult !== 0) {
+    log("github release failed. Aborting.");
+    return;
+  }
 
-  // ---------------------------------------------------------------------------
-  log(`Step 10/${STEPS}: publishing module on npm...`);
+  log(`Step 8/${STEPS}: publishing module on npm...`);
   await execCommand("npm run publish");
-
+  
   log("Owl Release process completed! Thank you for your patience");
+  await execCommand(`gh release view`);
+  await execCommand(`gh release view -w`);
+
 }
 
 // -----------------------------------------------------------------------------
@@ -199,16 +177,3 @@ async function replaceInFile(file, from, to) {
     });
   });
 }
-
-function createRelease(token, options) {
-  return new Promise((resolve, reject) => {
-    var gh = new GitHub({ token });
-    gh.getRepo("odoo", "owl").createRelease(options, (err, result, req) => {
-      if (err) {
-        reject(err);
-      } else {
-        resolve(result);
-      }
-    });
-  });
-}

tools/server.py

@@ -14,9 +14,9 @@ URL = 'http://{0}:{1}/tools'.format(HOST, PORT)
 # With this, we can simply copy the playground folder as is in the gh-page when
 # we want to update the playground.
 class OWLHandler(SimpleHTTPRequestHandler):
-    def do_GET(self):
+    def do_GET(self): 
         if self.path == '/tools/owl.js':
-            self.path = '/dist/owl.js'
+            self.path = '/dist/owl.iife.js'
         return SimpleHTTPRequestHandler.do_GET(self)
 
     def end_headers(self):

tsconfig.json

@@ -1,20 +1,107 @@
 {
+  /**
+   ** Commented-out options have their default values.
+   **/
+  "include": [
+    "src/**/*.ts",
+    "src/*.ts"
+  ],
+                                                                // "exclude": [],
+  // "files": [],                                               // A list of relative or absolute file paths to include.
+  // "extends": "",                                             // A string containing a path to another configuration file to inherit from.
+  // "references": [],                                          // An array of objects `{"path": "./to/dirOrConfig"}` that specifies projects to reference.
+  // "compileOnSave": false,                                    // Signals to the IDE to generate all files for a given tsconfig.json upon saving.
   "compilerOptions": {
-    "module": "commonjs",
-    "preserveConstEnums": true,
-    "noImplicitThis": true,
-    "removeComments": false,
-    "declaration": true,
-    "target": "esnext",
-    "outDir": "dist",
-    "alwaysStrict": true,
-    "noUnusedLocals": true,
-    "noUnusedParameters": false,
-    "noImplicitReturns": true,
-    "noFallthroughCasesInSwitch": true,
-    "strictPropertyInitialization": true,
-    "strictNullChecks": true,
-    "declarationDir": "dist/types"
-  },
-  "include": ["src/**/*.ts","src/*.ts"]
+                                                                // Main options
+    "target": "esnext",                                         // Specify ECMAScript target version: 'es3' (default), 'es5', 'es2015', 'es2016', 'es2017','es2018' or 'esnext'.
+    "module": "esnext",                                         // Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'.
+    // "lib": ["esnext", "dom"],                                // Specify library files to be included in the compilation.
+    // "allowJs": false,                                        // Allow javascript files to be compiled.
+    // "checkJs": false,                                        // Report errors in .js files.
+    // "outFile": "./",                                         // Concatenate and emit output to single file.
+    "outDir": "dist",                                           // Redirect output structure to the directory.
+    // "rootDir": "./",                                         // Specify the root directory of input files. Use to control the output directory structure with `--outDir`.
+    // "project": "",                                           // Compile a project given a valid configuration file.
+                                                                // Compilation options
+    // "composite": true,                                       // Enable project compilation
+    // "diagnostics": false,                                    // Show diagnostic information.
+    // "incremental": true,                                     // Enable incremental compilation by reading/writing information from prior compilations to a file on disk.
+    // "isolatedModules": false,                                // Transpile each file as a separate module (similar to 'ts.transpileModule').
+    // "listEmittedFiles": false,                               // Print names of generated files part of the compilation.
+    // "listFiles": true,                                       // Print names of files part of the compilation.
+    // "noErrorTruncation": false,                              // Do not truncate error messages.
+    // "preserveWatchOutput": false,                            // Keep outdated console output in watch mode instead of clearing the screen.
+    // "traceResolution": false,                                // Enable tracing of the name resolution process.
+    // "tsBuildInfoFile": ".tsbuildinfo",                       // Specify file to store incremental compilation information.
+                                                                // Strict typechecking options
+    // "strict": false,                                         // Enable all strict type-checking options.
+    // "noImplicitAny": true,                                   // Raise error on expressions and declarations with an implied 'any' type.
+    // "noImplicitThis": true,                                  // Raise error on 'this' expressions with an implied 'any' type.
+    // "strictBindCallApply": true,                             // Enable stricter checking of of the `bind`, `call`, and `apply` methods on functions.
+    // "strictFunctionTypes": true,                             // Disable bivariant parameter checking for function types.
+    // "strictNullChecks": true,                                // In strict null checking mode, the null and undefined values are not in the domain of every type and are only assignable to themselves and any.
+    // "strictPropertyInitialization": true,                    // Ensure non-undefined class properties are initialized in the constructor. This option requires `--strictNullChecks` be enabled in order to take effect.
+    // "alwaysStrict": true,                                    // Parse in strict mode and emit "use strict" for each source file.
+                                                                // Additional checks
+    // "allowUnreachableCode": false,                           // Do not report errors on unreachable code.
+    // "allowUnusedLabels": false,                              // Do not report errors on unused labels.
+    "forceConsistentCasingInFileNames": true,                   // Disallow inconsistently-cased references to the same file.
+    // "noStrictGenericChecks": false,                          // Disable strict checking of generic signatures in function types.
+    "noUnusedLocals": true,                                     // Report errors on unused locals.
+    "noUnusedParameters": false,                                // Report errors on unused parameters.
+    "noImplicitReturns": true,                                  // Report error when not all code paths in function return a value.
+    "noFallthroughCasesInSwitch": true,                         // Report errors for fallthrough cases in switch statement.
+    // "skipLibCheck": false,                                   // Skip type checking of all declaration files (*.d.ts).
+    // "suppressExcessPropertyErrors": false,                   // Suppress excess property checks for object literals.
+    // "suppressImplicitAnyIndexErrors": false,                 // Suppress noImplicitAny errors for indexing objects lacking index signatures.
+                                                                // Module resolution options
+    "moduleResolution": "node",                                 // Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6).
+    // "baseUrl": "./",                                         // Base directory to resolve non-absolute module names.
+    // "paths": {},                                             // A series of entries which re-map imports to lookup locations relative to the 'baseUrl'.
+    // "rootDirs": [],                                          // List of root folders whose combined content represents the structure of the project at runtime.
+    // "typeRoots": [],                                         // List of folders to include type definitions from.
+    "types": [
+      "jest",
+      "node"
+    ],                                                // Type declaration files to be included in compilation.
+    // "allowSyntheticDefaultImports": false                    // Allow default imports from modules with no default export. This does not affect code emit, just typechecking.
+    "esModuleInterop": true,                                    // Emit '__importStar' and '__importDefault' helpers for runtime babel ecosystem compatibility and enable '--allowSyntheticDefaultImports' for typesystem compatibility.
+    // "maxNodeModuleJsDepth": 0,                               // The maximum dependency depth to search under node_modules and load JavaScript files. Only applicable with --allowJs.
+    // "preserveSymlinks": false,                               // Do not resolve the real path of symlinks.
+    "resolveJsonModule": true,                                  // Include modules imported with '.json' extension.
+                                                                // Emit options
+    "declaration": true,                                        // Generates corresponding '.d.ts' file.
+    "declarationDir": "dist/types",                             // Output directory for generated declaration files.
+    // "declarationMap": false,                                 // Generates a sourcemap for each corresponding '.d.ts' file.
+    // "emitBOM": false,                                        // Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files.
+    // "emitDeclarationOnly": false,                            // Only emit ‘.d.ts’ declaration files.
+    // "importHelpers": false,                                  // Import emit helpers from 'tslib'.
+    // "newLine": "LF",                                         // Use the specified end of line sequence to be used when emitting files: "crlf" (windows) or "lf" (unix).”
+    // "noEmit": true,                                          // Do not emit outputs.
+    // "noEmitHelpers": false,                                  // Do not generate custom helper functions like __extends in compiled output.
+    // "noEmitOnError": false,                                  // Do not emit outputs if any errors were reported.
+    // "noImplicitUseStrict": false,                            // Do not emit "use strict" directives in module output.
+    // "noResolve": false,                                      // Do not add triple-slash references or module import targets to the list of compiled files.
+    "preserveConstEnums": true,                                 // Do not erase const enum declarations in generated code.
+    // "removeComments": false,                                 // Remove all comments except copy-right header comments beginning with 
+    // "experimentalDecorators": true,                          // Enables experimental support for ES7 decorators.
+    // "emitDecoratorMetadata": true,                           // Enables experimental support for emitting type metadata for decorators.
+                                                                // Source map options
+    // "sourceMap": false,                                      // Generates corresponding '.map' file.
+    // "sourceRoot": "",                                        // Specify the location where debugger should locate TypeScript files instead of source locations.
+    // "mapRoot": "",                                           // Specify the location where debugger should locate map files instead of generated locations.
+    // "inlineSourceMap": true,                                 // Emit a single file with source maps instead of having a separate file.
+    // "inlineSources": true,                                   // Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set.
+                                                                // JSX options
+    // "jsx": "preserve",                                       // Specify JSX code generation: 'preserve', 'react-native', or 'react'.
+    // "jsxFactory": "React.createElement",                     // Specify the JSX factory function to use when targeting react JSX emit, e.g. 'React.createElement' or 'h'.
+                                                                // Other options
+    // "allowUmdGlobalAccess": true,                            // Allow accessing UMD globals from modules.
+    // "charset": "utf8",                                       // The character set of the input files.
+    // "downlevelIteration": false,                             // Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'.
+    // "disableSizeLimit": false,                               // Disable size limitation on JavaScript project.
+    // "keyofStringsOnly": false,                               // Resolve 'keyof' to string valued property names only (no numbers or symbols).
+    // "noLib": false,                                          // Do not include the default library file (lib.d.ts).
+    // "pretty": true,                                          // Stylize errors and messages using color and context.
+  }
 }