[FIX] portal: correctly mount portal content in target created by mount

Previously, blah blah blah
[FIX] blockdom: correctly reorder children in heterogeneous t-foreach
2025-10-06 19:59:41 +07:00 · 2022-10-19 14:39:44 +02:00 · 2022-10-19 13:11:44 +02:00 · 2022-10-10 20:33:18 +02:00 · 2022-10-10 13:53:11 +02:00 · 2022-10-07 15:27:58 +02:00
52 changed files with 1549 additions and 575 deletions
@@ -124,5 +124,5 @@ npm install @odoo/owl

 If you want to use a simple `<script>` tag, the last release can be downloaded here:

- [owl-1.4.10](https://github.com/odoo/owl/releases/tag/v1.4.10)
+- [owl](https://github.com/odoo/owl/releases/latest)

@@ -770,10 +770,11 @@ For reference, here is the final code:
    <meta charset="UTF-8" />
    <title>OWL Todo App</title>
    <link rel="stylesheet" href="app.css" />
+  </head>
+  <body>
    <script src="owl.js"></script>
    <script src="app.js"></script>
-  </head>
-  <body></body>
+  </body>
 </html>
 ```

@@ -234,7 +234,8 @@ are defined by a function instead of just the dependencies.

 The `useEffect` hook takes two function: the effect function and the dependency
 function. The effect function perform some task and return (optionally) a cleanup
-function. The dependency function returns a list of dependencies. If any of these
+function. The dependency function returns a list of dependencies, these dependencies
+are passed as parameters in the effect function . If any of these
 dependencies changes, then the current effect will be cleaned up and reexecuted.

 Here is an example without any dependencies:
@@ -1,6 +1,6 @@
 {
  "name": "@odoo/owl",
-  "version": "2.0.0-beta-17",
+  "version": "2.0.0",
  "description": "Odoo Web Library (OWL)",
  "main": "dist/owl.cjs.js",
  "module": "dist/owl.es.js",
@@ -1,28 +1,9 @@
 # 🦉 OWL Roadmap 🦉

- Current version: 1.4.10
+- Current version: 2.X
 - Status: stable

-This roadmap is only an attempt at predicting Owl's future.  Everything may
-change!
-
-
-### 1.x
-
- add chrome and firefox devtools,
- fix every bugs,
- improve documentation,
- small backward compatible improvements.
-
-### 2.x (2020? 2021? 2022?)
-
- stop support for `t-set` directive to define the content of a slot
-
-Maybe:
-
- reimplement vdom to use *block* system, like Vue 3, which should make Owl
-  much faster
- refactor `QWeb` to use an intermediate representation (some kind of AST) to
-  allow additional optimisations.
-
+Owl is currently stable. No (large) improvements is expected in the near future.

+Note that we intend to keep maintaining owl, and as such, improvements and/or
+breaking changes may require a version bump in the future.
@@ -214,6 +214,14 @@ class CodeTarget {
    result.push(`}`);
    return result.join("\n  ");
  }
+
+  currentKey(ctx: Context) {
+    let key = this.loopLevel ? `key${this.loopLevel}` : "key";
+    if (ctx.tKeyExpr) {
+      key = `${ctx.tKeyExpr} + ${key}`;
+    }
+    return key;
+  }
 }

 const TRANSLATABLE_ATTRS = ["label", "title", "placeholder", "alt"];
@@ -232,6 +240,7 @@ export class CodeGenerator {
  translatableAttributes: string[] = TRANSLATABLE_ATTRS;
  ast: AST;
  staticDefs: { id: string; expr: string }[] = [];
+  slotNames: Set<String> = new Set();
  helpers: Set<string> = new Set();

  constructor(ast: AST, options: CodeGenOptions) {
@@ -364,19 +373,15 @@ export class CodeGenerator {

  insertBlock(expression: string, block: BlockDescription, ctx: Context): void {
    let blockExpr = block.generateExpr(expression);
-    const tKeyExpr = ctx.tKeyExpr;
    if (block.parentVar) {
-      let keyArg = `key${this.target.loopLevel}`;
-      if (tKeyExpr) {
-        keyArg = `${tKeyExpr} + ${keyArg}`;
-      }
+      let key = this.target.currentKey(ctx);
      this.helpers.add("withKey");
-      this.addLine(`${block.parentVar}[${ctx.index}] = withKey(${blockExpr}, ${keyArg});`);
+      this.addLine(`${block.parentVar}[${ctx.index}] = withKey(${blockExpr}, ${key});`);
      return;
    }

-    if (tKeyExpr) {
-      blockExpr = `toggler(${tKeyExpr}, ${blockExpr})`;
+    if (ctx.tKeyExpr) {
+      blockExpr = `toggler(${ctx.tKeyExpr}, ${blockExpr})`;
    }

    if (block.isRoot && !ctx.preventRoot) {
@@ -423,78 +428,66 @@ export class CodeGenerator {
      .join("");
  }

-  compileAST(ast: AST, ctx: Context) {
+  /**
+   * @returns the newly created block name, if any
+   */
+  compileAST(ast: AST, ctx: Context): string | null {
    switch (ast.type) {
      case ASTType.Comment:
-        this.compileComment(ast, ctx);
-        break;
+        return this.compileComment(ast, ctx);
      case ASTType.Text:
-        this.compileText(ast, ctx);
-        break;
+        return this.compileText(ast, ctx);
      case ASTType.DomNode:
-        this.compileTDomNode(ast, ctx);
-        break;
+        return this.compileTDomNode(ast, ctx);
      case ASTType.TEsc:
-        this.compileTEsc(ast, ctx);
-        break;
+        return this.compileTEsc(ast, ctx);
      case ASTType.TOut:
-        this.compileTOut(ast, ctx);
-        break;
+        return this.compileTOut(ast, ctx);
      case ASTType.TIf:
-        this.compileTIf(ast, ctx);
-        break;
+        return this.compileTIf(ast, ctx);
      case ASTType.TForEach:
-        this.compileTForeach(ast, ctx);
-        break;
+        return this.compileTForeach(ast, ctx);
      case ASTType.TKey:
-        this.compileTKey(ast, ctx);
-        break;
+        return this.compileTKey(ast, ctx);
      case ASTType.Multi:
-        this.compileMulti(ast, ctx);
-        break;
+        return this.compileMulti(ast, ctx);
      case ASTType.TCall:
-        this.compileTCall(ast, ctx);
-        break;
+        return this.compileTCall(ast, ctx);
      case ASTType.TCallBlock:
-        this.compileTCallBlock(ast, ctx);
-        break;
+        return this.compileTCallBlock(ast, ctx);
      case ASTType.TSet:
-        this.compileTSet(ast, ctx);
-        break;
+        return this.compileTSet(ast, ctx);
      case ASTType.TComponent:
-        this.compileComponent(ast, ctx);
-        break;
+        return this.compileComponent(ast, ctx);
      case ASTType.TDebug:
-        this.compileDebug(ast, ctx);
-        break;
+        return this.compileDebug(ast, ctx);
      case ASTType.TLog:
-        this.compileLog(ast, ctx);
-        break;
+        return this.compileLog(ast, ctx);
      case ASTType.TSlot:
-        this.compileTSlot(ast, ctx);
-        break;
+        return this.compileTSlot(ast, ctx);
      case ASTType.TTranslation:
-        this.compileTTranslation(ast, ctx);
-        break;
+        return this.compileTTranslation(ast, ctx);
      case ASTType.TPortal:
-        this.compileTPortal(ast, ctx);
+        return this.compileTPortal(ast, ctx);
    }
  }

-  compileDebug(ast: ASTDebug, ctx: Context) {
+  compileDebug(ast: ASTDebug, ctx: Context): string | null {
    this.addLine(`debugger;`);
    if (ast.content) {
-      this.compileAST(ast.content, ctx);
+      return this.compileAST(ast.content, ctx);
    }
+    return null;
  }

-  compileLog(ast: ASTLog, ctx: Context) {
+  compileLog(ast: ASTLog, ctx: Context): string | null {
    this.addLine(`console.log(${compileExpr(ast.expr)});`);
    if (ast.content) {
-      this.compileAST(ast.content, ctx);
+      return this.compileAST(ast.content, ctx);
    }
+    return null;
  }
-  compileComment(ast: ASTComment, ctx: Context) {
+  compileComment(ast: ASTComment, ctx: Context): string {
    let { block, forceNewBlock } = ctx;
    const isNewBlock = !block || forceNewBlock;
    if (isNewBlock) {
@@ -507,9 +500,10 @@ export class CodeGenerator {
      const text = xmlDoc.createComment(ast.value);
      block!.insert(text);
    }
+    return block!.varName;
  }

-  compileText(ast: ASTText, ctx: Context) {
+  compileText(ast: ASTText, ctx: Context): string {
    let { block, forceNewBlock } = ctx;

    let value = ast.value;
@@ -528,6 +522,7 @@ export class CodeGenerator {
      const createFn = ast.type === ASTType.Text ? xmlDoc.createTextNode : xmlDoc.createComment;
      block.insert(createFn.call(xmlDoc, value));
    }
+    return block.varName;
  }

  generateHandlerCode(rawEvent: string, handler: string): string {
@@ -547,7 +542,7 @@ export class CodeGenerator {
    return `[${modifiersCode}${this.captureExpression(handler)}, ctx]`;
  }

-  compileTDomNode(ast: ASTDomNode, ctx: Context) {
+  compileTDomNode(ast: ASTDomNode, ctx: Context): string {
    let { block, forceNewBlock } = ctx;
    const isNewBlock = !block || forceNewBlock || ast.dynamicTag !== null || ast.ns;
    let codeIdx = this.target.code.length;
@@ -734,9 +729,10 @@ export class CodeGenerator {
        this.addLine(`let ${block!.children.map((c) => c.varName)};`, codeIdx);
      }
    }
+    return block!.varName;
  }

-  compileTEsc(ast: ASTTEsc, ctx: Context) {
+  compileTEsc(ast: ASTTEsc, ctx: Context): string {
    let { block, forceNewBlock } = ctx;
    let expr: string;
    if (ast.expr === "0") {
@@ -757,9 +753,10 @@ export class CodeGenerator {
      const text = xmlDoc.createElement(`block-text-${idx}`);
      block.insert(text);
    }
+    return block.varName;
  }

-  compileTOut(ast: ASTTOut, ctx: Context) {
+  compileTOut(ast: ASTTOut, ctx: Context): string {
    let { block } = ctx;
    if (block) {
      this.insertAnchor(block);
@@ -781,6 +778,7 @@ export class CodeGenerator {
      blockStr = `safeOutput(${compileExpr(ast.expr)})`;
    }
    this.insertBlock(blockStr, block, ctx);
+    return block.varName;
  }

  compileTIfBranch(content: AST, block: BlockDescription, ctx: Context) {
@@ -794,7 +792,7 @@ export class CodeGenerator {
    this.target.indentLevel--;
  }

-  compileTIf(ast: ASTTif, ctx: Context, nextNode?: ASTDomNode) {
+  compileTIf(ast: ASTTif, ctx: Context, nextNode?: ASTDomNode): string {
    let { block, forceNewBlock } = ctx;
    const codeIdx = this.target.code.length;
    const isNewBlock = !block || (block.type !== "multi" && forceNewBlock);
@@ -837,9 +835,10 @@ export class CodeGenerator {
      const args = block!.children.map((c) => c.varName).join(", ");
      this.insertBlock(`multi([${args}])`, block!, ctx)!;
    }
+    return block.varName;
  }

-  compileTForeach(ast: ASTTForEach, ctx: Context) {
+  compileTForeach(ast: ASTTForEach, ctx: Context): string {
    let { block } = ctx;
    if (block) {
      this.insertAnchor(block);
@@ -878,9 +877,9 @@ export class CodeGenerator {
      // Throw error on duplicate keys in dev mode
      this.helpers.add("OwlError");
      this.addLine(
-        `if (keys${block.id}.has(key${this.target.loopLevel})) { throw new OwlError(\`Got duplicate key in t-foreach: \${key${this.target.loopLevel}}\`)}`
+        `if (keys${block.id}.has(String(key${this.target.loopLevel}))) { throw new OwlError(\`Got duplicate key in t-foreach: \${key${this.target.loopLevel}}\`)}`
      );
-      this.addLine(`keys${block.id}.add(key${this.target.loopLevel});`);
+      this.addLine(`keys${block.id}.add(String(key${this.target.loopLevel}));`);
    }
    let id: string;
    if (ast.memo) {
@@ -917,9 +916,10 @@ export class CodeGenerator {
      this.addLine(`ctx = ctx.__proto__;`);
    }
    this.insertBlock("l", block, ctx);
+    return block.varName;
  }

-  compileTKey(ast: ASTTKey, ctx: Context) {
+  compileTKey(ast: ASTTKey, ctx: Context): string | null {
    const tKeyExpr = generateId("tKey_");
    this.define(tKeyExpr, compileExpr(ast.expr));
    ctx = createContext(ctx, {
@@ -927,20 +927,22 @@ export class CodeGenerator {
      block: ctx.block,
      index: ctx.index,
    });
-    this.compileAST(ast.content, ctx);
+    return this.compileAST(ast.content, ctx);
  }

-  compileMulti(ast: ASTMulti, ctx: Context) {
+  compileMulti(ast: ASTMulti, ctx: Context): string | null {
    let { block, forceNewBlock } = ctx;
    const isNewBlock = !block || forceNewBlock;
    let codeIdx = this.target.code.length;
    if (isNewBlock) {
      const n = ast.content.filter((c) => c.type !== ASTType.TSet).length;
+      let result: string | null = null;
      if (n <= 1) {
        for (let child of ast.content) {
-          this.compileAST(child, ctx);
+          const blockName = this.compileAST(child, ctx);
+          result = result || blockName;
        }
-        return;
+        return result;
      }
      block = this.createBlock(block, "multi", ctx);
    }
@@ -980,9 +982,10 @@ export class CodeGenerator {
      const args = block!.children.map((c) => c.varName).join(", ");
      this.insertBlock(`multi([${args}])`, block!, ctx)!;
    }
+    return block!.varName;
  }

-  compileTCall(ast: ASTTCall, ctx: Context) {
+  compileTCall(ast: ASTTCall, ctx: Context): string {
    let { block, forceNewBlock } = ctx;
    let ctxVar = ctx.ctxVar || "ctx";
    if (ast.context) {
@@ -993,12 +996,11 @@ export class CodeGenerator {
      this.addLine(`${ctxVar} = Object.create(${ctxVar});`);
      this.addLine(`${ctxVar}[isBoundary] = 1;`);
      this.helpers.add("isBoundary");
-      const nextId = BlockDescription.nextBlockId;
      const subCtx = createContext(ctx, { preventRoot: true, ctxVar });
-      this.compileAST({ type: ASTType.Multi, content: ast.body }, subCtx);
-      if (nextId !== BlockDescription.nextBlockId) {
+      const bl = this.compileMulti({ type: ASTType.Multi, content: ast.body }, subCtx);
+      if (bl) {
        this.helpers.add("zero");
-        this.addLine(`${ctxVar}[zero] = b${nextId};`);
+        this.addLine(`${ctxVar}[zero] = ${bl};`);
      }
    }
    const isDynamic = INTERP_REGEXP.test(ast.name);
@@ -1032,9 +1034,10 @@ export class CodeGenerator {
    if (ast.body && !ctx.isLast) {
      this.addLine(`${ctxVar} = ${ctxVar}.__proto__;`);
    }
+    return block.varName;
  }

-  compileTCallBlock(ast: ASTTCallBlock, ctx: Context) {
+  compileTCallBlock(ast: ASTTCallBlock, ctx: Context): string {
    let { block, forceNewBlock } = ctx;
    if (block) {
      if (!forceNewBlock) {
@@ -1043,9 +1046,10 @@ export class CodeGenerator {
    }
    block = this.createBlock(block, "multi", ctx);
    this.insertBlock(compileExpr(ast.name), block, { ...ctx, forceNewBlock: !block });
+    return block.varName;
  }

-  compileTSet(ast: ASTTSet, ctx: Context) {
+  compileTSet(ast: ASTTSet, ctx: Context): null {
    this.target.shouldProtectScope = true;
    this.helpers.add("isBoundary").add("withDefault");
    const expr = ast.value ? compileExpr(ast.value || "") : "null";
@@ -1053,7 +1057,8 @@ export class CodeGenerator {
      this.helpers.add("LazyValue");
      const bodyAst: AST = { type: ASTType.Multi, content: ast.body };
      const name = this.compileInNewTarget("value", bodyAst, ctx);
-      let value = `new LazyValue(${name}, ctx, this, node)`;
+      let key = this.target.currentKey(ctx);
+      let value = `new LazyValue(${name}, ctx, this, node, ${key})`;
      value = ast.value ? (value ? `withDefault(${expr}, ${value})` : expr) : value;
      this.addLine(`ctx[\`${ast.name}\`] = ${value};`);
    } else {
@@ -1070,6 +1075,7 @@ export class CodeGenerator {
      this.helpers.add("setContextValue");
      this.addLine(`setContextValue(${ctx.ctxVar || "ctx"}, "${ast.name}", ${value});`);
    }
+    return null;
  }

  generateComponentKey() {
@@ -1121,7 +1127,7 @@ export class CodeGenerator {
    return propString;
  }

-  compileComponent(ast: ASTComponent, ctx: Context) {
+  compileComponent(ast: ASTComponent, ctx: Context): string {
    let { block } = ctx;
    // props
    const hasSlotsProp = "slots" in (ast.props || {});
@@ -1187,7 +1193,7 @@ export class CodeGenerator {
    }

    if (this.dev) {
-      this.addLine(`helpers.validateProps(${expr}, ${propVar!}, ctx);`);
+      this.addLine(`helpers.validateProps(${expr}, ${propVar!}, this);`);
    }

    if (block && (ctx.forceNewBlock === false || ctx.tKeyExpr)) {
@@ -1221,6 +1227,7 @@ export class CodeGenerator {

    block = this.createBlock(block, "multi", ctx);
    this.insertBlock(blockExpr, block, ctx);
+    return block.varName;
  }

  wrapWithEventCatcher(expr: string, on: EventHandlers): string {
@@ -1239,34 +1246,43 @@ export class CodeGenerator {
    return `${name}(${expr}, [${handlers.join(",")}])`;
  }

-  compileTSlot(ast: ASTSlot, ctx: Context) {
+  compileTSlot(ast: ASTSlot, ctx: Context): string {
    this.helpers.add("callSlot");
    let { block } = ctx;
    let blockString: string;
    let slotName;
    let dynamic = false;
+    let isMultiple = false;
    if (ast.name.match(INTERP_REGEXP)) {
      dynamic = true;
+      isMultiple = true;
      slotName = interpolate(ast.name);
    } else {
      slotName = "'" + ast.name + "'";
+      isMultiple = isMultiple || this.slotNames.has(ast.name);
+      this.slotNames.add(ast.name);
    }
    const dynProps = ast.attrs ? ast.attrs["t-props"] : null;
    if (ast.attrs) {
      delete ast.attrs["t-props"];
    }
+    let key = this.target.loopLevel ? `key${this.target.loopLevel}` : "key";
+    if (isMultiple) {
+      key = `${key} + \`${this.generateComponentKey()}\``;
+    }
+
    const props = ast.attrs ? this.formatPropObject(ast.attrs) : [];
    const scope = this.getPropString(props, dynProps);
    if (ast.defaultContent) {
      const name = this.compileInNewTarget("defaultContent", ast.defaultContent, ctx);
-      blockString = `callSlot(ctx, node, key, ${slotName}, ${dynamic}, ${scope}, ${name})`;
+      blockString = `callSlot(ctx, node, ${key}, ${slotName}, ${dynamic}, ${scope}, ${name})`;
    } else {
      if (dynamic) {
        let name = generateId("slot");
        this.define(name, slotName);
-        blockString = `toggler(${name}, callSlot(ctx, node, key, ${name}, ${dynamic}, ${scope}))`;
+        blockString = `toggler(${name}, callSlot(ctx, node, ${key}, ${name}, ${dynamic}, ${scope}))`;
      } else {
-        blockString = `callSlot(ctx, node, key, ${slotName}, ${dynamic}, ${scope})`;
+        blockString = `callSlot(ctx, node, ${key}, ${slotName}, ${dynamic}, ${scope})`;
      }
    }
    // event handling
@@ -1279,14 +1295,16 @@ export class CodeGenerator {
    }
    block = this.createBlock(block, "multi", ctx);
    this.insertBlock(blockString, block, { ...ctx, forceNewBlock: false });
+    return block.varName;
  }

-  compileTTranslation(ast: ASTTranslation, ctx: Context) {
+  compileTTranslation(ast: ASTTranslation, ctx: Context): string | null {
    if (ast.content) {
-      this.compileAST(ast.content, Object.assign({}, ctx, { translate: false }));
+      return this.compileAST(ast.content, Object.assign({}, ctx, { translate: false }));
    }
+    return null;
  }
-  compileTPortal(ast: ASTTPortal, ctx: Context) {
+  compileTPortal(ast: ASTTPortal, ctx: Context): string {
    if (!this.staticDefs.find((d) => d.id === "Portal")) {
      this.staticDefs.push({ id: "Portal", expr: `app.Portal` });
    }
@@ -1313,5 +1331,6 @@ export class CodeGenerator {
    }
    block = this.createBlock(block, "multi", ctx);
    this.insertBlock(blockString, block, { ...ctx, forceNewBlock: false });
+    return block.varName;
  }
 }
@@ -781,8 +781,9 @@ function parseComponent(node: Element, ctx: ParsingContext): AST | null {

    // default slot
    const defaultContent = parseChildNodes(clone, ctx);
-    if (defaultContent) {
-      slots = slots || {};
+    slots = slots || {};
+    // t-set-slot="default" has priority over content
+    if (defaultContent && !slots.default) {
      slots.default = { content: defaultContent, on, attrs: null, scope: defaultSlotScope };
    }
  }
@@ -6,6 +6,7 @@ import { Scheduler } from "./scheduler";
 import { validateProps } from "./template_helpers";
 import { TemplateSet, TemplateSetConfig } from "./template_set";
 import { validateTarget } from "./utils";
+import { handleError } from "./error_handling";

 // reimplement dev mode stuff see last change in 0f7a8289a6fb8387c3c1af41c6664b2a8448758f

@@ -94,9 +95,7 @@ export class App<
        nodeErrorHandlers.set(node, handlers);
      }
      handlers.unshift((e) => {
-        if (isResolved) {
-          console.error(e);
-        } else {
+        if (!isResolved) {
          reject(e);
        }
        throw e;
@@ -169,6 +168,10 @@ export class App<
      return node;
    };
  }
+
+  handleError(...args: Parameters<typeof handleError>) {
+    return handleError(...args);
+  }
 }

 export async function mount<
@@ -157,6 +157,15 @@ function buildTree(
          : document.createElement(tagName);
      }
      if (el instanceof Element) {
+        if (!domParentTree) {
+          // some html elements may have side effects when setting their attributes.
+          // For example, setting the src attribute of an <img/> will trigger a
+          // request to get the corresponding image. This is something that we
+          // don't want at compile time. We avoid that by putting the content of
+          // the block in a <template/> element
+          const fragment = document.createElement("template").content;
+          fragment.appendChild(el);
+        }
        for (let i = 0; i < attrs.length; i++) {
          const attrName = attrs[i].name;
          const attrValue = attrs[i].value;
@@ -508,9 +517,12 @@ function createBlockClass(template: HTMLElement, ctx: BlockCtx): BlockClass {
      return this.el!;
    }

-    moveBefore(other: Block | null, afterNode: Node | null) {
-      const target = other ? other.el! : afterNode;
-      nodeInsertBefore.call(this.parentEl, this.el!, target);
+    moveBeforeDOMNode(node: Node | null) {
+      nodeInsertBefore.call(this.parentEl, this.el!, node);
+    }
+
+    moveBeforeVNode(other: Block | null, afterNode: Node | null) {
+      nodeInsertBefore.call(this.parentEl, this.el!, other ? other.el! : afterNode);
    }

    toString() {
@@ -56,8 +56,17 @@ export function createCatcher(eventsSpec: EventsSpec): Catcher {
      }
    }

-    moveBefore(other: VCatcher | null, afterNode: Node | null) {
-      this.child.moveBefore(other ? other.child : null, afterNode);
+    moveBeforeDOMNode(node: Node | null) {
+      this.child.moveBeforeDOMNode(node);
+      this.parentEl!.insertBefore(this.afterNode!, node);
+    }
+
+    moveBeforeVNode(other: VCatcher | null, afterNode: Node | null) {
+      if (other) {
+        // check this with @ged-odoo for use in foreach
+        afterNode = other.firstNode() || afterNode;
+      }
+      this.child.moveBeforeVNode(other ? other.child : null, afterNode);
      this.parentEl!.insertBefore(this.afterNode!, afterNode);
    }

@@ -27,8 +27,8 @@ function createElementHandler(evName: string, capture: boolean = false): EventHa
  }

  function listener(ev: Event) {
-    const currentTarget = ev.currentTarget;
-    if (!currentTarget || !document.contains(currentTarget as HTMLElement)) return;
+    const currentTarget = ev.currentTarget as HTMLElement;
+    if (!currentTarget || !currentTarget.ownerDocument.contains(currentTarget)) return;
    const data = (currentTarget as any)[eventKey];
    if (!data) return;
    config.mainEventHandler(data, ev, currentTarget);
@@ -29,14 +29,18 @@ class VHtml {
    }
  }

-  moveBefore(other: VHtml | null, afterNode: Node | null) {
-    const target = other ? other.content[0] : afterNode;
+  moveBeforeDOMNode(node: Node | null) {
    const parent = this.parentEl;
    for (let elem of this.content) {
-      nodeInsertBefore.call(parent, elem, target);
+      nodeInsertBefore.call(parent, elem, node);
    }
  }

+  moveBeforeVNode(other: VHtml | null, afterNode: Node | null) {
+    const target = other ? other.content[0] : afterNode;
+    this.moveBeforeDOMNode(target);
+  }
+
  patch(other: VHtml) {
    if (this === other) {
      return;
@@ -10,7 +10,8 @@ export { createCatcher } from "./event_catcher";

 export interface VNode<T = any> {
  mount(parent: HTMLElement, afterNode: Node | null): void;
-  moveBefore(other: T | null, afterNode: Node | null): void;
+  moveBeforeDOMNode(node: Node | null): void;
+  moveBeforeVNode(other: T | null, afterNode: Node | null): void;
  patch(other: T, withBeforeRemove: boolean): void;
  beforeRemove(): void;
  remove(): void;
@@ -38,14 +38,22 @@ class VList {
    this.parentEl = parent;
  }

-  moveBefore(other: VList | null, afterNode: Node | null) {
+  moveBeforeDOMNode(node: Node | null) {
+    const children = this.children;
+    for (let i = 0, l = children.length; i < l; i++) {
+      children[i].moveBeforeDOMNode(node);
+    }
+    this.parentEl!.insertBefore(this.anchor!, node);
+  }
+
+  moveBeforeVNode(other: VList | null, afterNode: Node | null) {
    if (other) {
      const next = other!.children[0];
      afterNode = (next ? next.firstNode() : other!.anchor) || null;
    }
    const children = this.children;
    for (let i = 0, l = children.length; i < l; i++) {
-      children[i].moveBefore(null, afterNode);
+      children[i].moveBeforeVNode(null, afterNode);
    }
    this.parentEl!.insertBefore(this.anchor!, afterNode);
  }
@@ -66,7 +74,7 @@ class VList {
      patch: cPatch,
      remove: cRemove,
      beforeRemove,
-      moveBefore: cMoveBefore,
+      moveBeforeVNode: cMoveBefore,
      firstNode: cFirstNode,
    } = proto;

@@ -38,7 +38,22 @@ export class VMulti {
    this.parentEl = parent;
  }

-  moveBefore(other: VMulti | null, afterNode: Node | null) {
+  moveBeforeDOMNode(node: Node | null) {
+    const children = this.children;
+    const parent = this.parentEl;
+    const anchors = this.anchors;
+    for (let i = 0, l = children.length; i < l; i++) {
+      let child = children[i];
+      if (child) {
+        child.moveBeforeDOMNode(node);
+      } else {
+        const anchor = anchors![i];
+        nodeInsertBefore.call(parent, anchor, node);
+      }
+    }
+  }
+
+  moveBeforeVNode(other: VMulti | null, afterNode: Node | null) {
    if (other) {
      const next = other!.children[0];
      afterNode = (next ? next.firstNode() : other!.anchors![0]) || null;
@@ -49,7 +64,7 @@ export class VMulti {
    for (let i = 0, l = children.length; i < l; i++) {
      let child = children[i];
      if (child) {
-        child.moveBefore(null, afterNode);
+        child.moveBeforeVNode(null, afterNode);
      } else {
        const anchor = anchors![i];
        nodeInsertBefore.call(parent, anchor, afterNode);
@@ -23,9 +23,12 @@ abstract class VSimpleNode {
    this.el = node;
  }

-  moveBefore(other: VText | null, afterNode: Node | null) {
-    const target = other ? other.el! : afterNode;
-    nodeInsertBefore.call(this.parentEl, this.el!, target);
+  moveBeforeDOMNode(node: Node | null) {
+    nodeInsertBefore.call(this.parentEl, this.el!, node);
+  }
+
+  moveBeforeVNode(other: VText | null, afterNode: Node | null) {
+    nodeInsertBefore.call(this.parentEl, this.el!, other ? other.el! : afterNode);
  }

  beforeRemove() {}
@@ -20,8 +20,12 @@ class VToggler {
    this.child.mount(parent, afterNode);
  }

-  moveBefore(other: VToggler | null, afterNode: Node | null) {
-    this.child.moveBefore(other ? other.child : null, afterNode);
+  moveBeforeDOMNode(node: Node | null) {
+    this.child.moveBeforeDOMNode(node);
+  }
+
+  moveBeforeVNode(other: VToggler | null, afterNode: Node | null) {
+    this.moveBeforeDOMNode((other && other.firstNode()) || afterNode);
  }

  patch(other: VToggler, withBeforeRemove: boolean) {
@@ -1,7 +1,7 @@
 import type { App, Env } from "./app";
 import { BDom, VNode } from "./blockdom";
 import { Component, ComponentConstructor, Props } from "./component";
-import { fibersInError, handleError, OwlError } from "./error_handling";
+import { fibersInError, OwlError } from "./error_handling";
 import { Fiber, makeChildFiber, makeRootFiber, MountFiber, MountOptions } from "./fibers";
 import {
  clearReactivesForCallback,
@@ -141,7 +141,7 @@ export class ComponentNode<P extends Props = any, E = any> implements VNode<Comp
    try {
      await Promise.all(this.willStart.map((f) => f.call(component)));
    } catch (e) {
-      handleError({ node: this, error: e });
+      this.app.handleError({ node: this, error: e });
      return;
    }
    if (this.status === STATUS.NEW && this.fiber === fiber) {
@@ -219,7 +219,7 @@ export class ComponentNode<P extends Props = any, E = any> implements VNode<Comp
          cb.call(component);
        }
      } catch (e) {
-        handleError({ error: e, node: this });
+        this.app.handleError({ error: e, node: this });
      }
    }
    this.status = STATUS.DESTROYED;
@@ -306,8 +306,12 @@ export class ComponentNode<P extends Props = any, E = any> implements VNode<Comp
    this.fiber = null;
  }

-  moveBefore(other: ComponentNode | null, afterNode: Node | null) {
-    this.bdom!.moveBefore(other ? other.bdom : null, afterNode);
+  moveBeforeDOMNode(node: Node | null): void {
+    this.bdom!.moveBeforeDOMNode(node);
+  }
+
+  moveBeforeVNode(other: ComponentNode<P, E> | null, afterNode: Node | null) {
+    this.bdom!.moveBeforeVNode(other ? other.bdom : null, afterNode);
  }

  patch() {
@@ -71,5 +71,6 @@ export function handleError(params: ErrorParams) {
    } catch (e) {
      console.error(e);
    }
+    throw error;
  }
 }
@@ -1,6 +1,6 @@
 import { BDom, mount } from "./blockdom";
 import type { ComponentNode } from "./component_node";
-import { fibersInError, handleError, OwlError } from "./error_handling";
+import { fibersInError, OwlError } from "./error_handling";
 import { STATUS } from "./status";

 export function makeChildFiber(node: ComponentNode, parent: Fiber): Fiber {
@@ -130,7 +130,7 @@ export class Fiber {
        (this.bdom as any) = true;
        this.bdom = node.renderFn();
      } catch (e) {
-        handleError({ node, error: e });
+        node.app.handleError({ node, error: e });
      }
      root.setCounter(root.counter - 1);
    }
@@ -195,7 +195,7 @@ export class RootFiber extends Fiber {
      }
    } catch (e) {
      this.locked = false;
-      handleError({ fiber: current || this, error: e });
+      node.app.handleError({ fiber: current || this, error: e });
    }
  }

@@ -259,7 +259,7 @@ export class MountFiber extends RootFiber {
        }
      }
    } catch (e) {
-      handleError({ fiber: current as Fiber, error: e });
+      this.node.app.handleError({ fiber: current as Fiber, error: e });
    }
  }
 }
@@ -1,4 +1,4 @@
-import { onWillUnmount } from "./lifecycle_hooks";
+import { onMounted, onWillUnmount } from "./lifecycle_hooks";
 import { BDom, text, VNode } from "./blockdom";
 import { Component } from "./component";
 import { OwlError } from "./error_handling";
@@ -6,60 +6,51 @@ import { OwlError } from "./error_handling";
 const VText: any = text("").constructor;

 class VPortal extends VText implements Partial<VNode<VPortal>> {
-  //   selector: string;
-  realBDom: BDom | null;
+  content: BDom | null;
+  selector: string;
  target: HTMLElement | null = null;

-  constructor(selector: string, realBDom: BDom) {
+  constructor(selector: string, content: BDom) {
    super("");
    this.selector = selector;
-    this.realBDom = realBDom;
+    this.content = content;
  }
+
  mount(parent: HTMLElement, anchor: ChildNode) {
    super.mount(parent, anchor);
    this.target = document.querySelector(this.selector) as any;
-    if (!this.target) {
-      let el: any = this.el;
-      while (el && el.parentElement instanceof HTMLElement) {
-        el = el.parentElement;
-      }
-      this.target = el && el.querySelector(this.selector);
-      if (!this.target) {
-        throw new OwlError("invalid portal target");
-      }
+    if (this.target) {
+      this.content!.mount(this.target!, null);
    }
-    this.realBDom!.mount(this.target!, null);
  }

  beforeRemove() {
-    this.realBDom!.beforeRemove();
-  }
-  remove() {
-    if (this.realBDom) {
-      super.remove();
-      this.realBDom!.remove();
-      this.realBDom = null;
+    // this.target not being null means content is mounted
+    if (this.target) {
+      this.content!.beforeRemove();
+      this.content!.remove();
    }
+    this.content = null;
  }

  patch(other: VPortal) {
    super.patch(other);
-    if (this.realBDom) {
-      this.realBDom.patch(other.realBDom!, true);
+    if (this.content) {
+      this.content.patch(other.content!, true);
    } else {
-      this.realBDom = other.realBDom;
-      this.realBDom!.mount(this.target!, null);
+      this.content = other.content;
+      this.content!.mount(this.target!, null);
    }
  }
 }

 /**
- * <t t-slot="default"/>
+ * kind of similar to <t t-slot="default"/>, but it wraps it around a VPortal
 */
 export function portalTemplate(app: any, bdom: any, helpers: any) {
  let { callSlot } = helpers;
-  return function template(ctx: any, node: any, key = "") {
-    return callSlot(ctx, node, key, "default", false, null);
+  return function template(ctx: any, node: any, key = ""): any {
+    return new VPortal(ctx.props.target, callSlot(ctx, node, key, "default", false, null));
  };
 }

@@ -73,13 +64,23 @@ export class Portal extends Component {
  };

  setup() {
-    const node = this.__owl__;
-    const renderFn = node.renderFn;
-    node.renderFn = () => new VPortal(this.props.target, renderFn());
-    onWillUnmount(() => {
-      if (node.bdom) {
-        node.bdom.remove();
+    const node: any = this.__owl__;
+
+    onMounted(() => {
+      const portal: VPortal = node.bdom;
+      if (!portal.target) {
+        portal.target = document.querySelector(this.props.target);
+        if (portal.target) {
+          portal.content!.mount(portal.target, null);
+        } else {
+          throw new OwlError("invalid portal target");
+        }
      }
    });
+
+    onWillUnmount(() => {
+      const portal: VPortal = node.bdom;
+      portal.beforeRemove();
+    });
  }
 }
@@ -111,15 +111,18 @@ class LazyValue {
  ctx: any;
  component: any;
  node: any;
-  constructor(fn: any, ctx: any, component: any, node: any) {
+  key: any;
+
+  constructor(fn: any, ctx: any, component: any, node: any, key: any) {
    this.fn = fn;
    this.ctx = capture(ctx);
    this.component = component;
    this.node = node;
+    this.key = key;
  }

  evaluate(): any {
-    return this.fn.call(this.component, this.ctx, this.node);
+    return this.fn.call(this.component, this.ctx, this.node, this.key);
  }

  toString() {
@@ -207,11 +210,11 @@ function multiRefSetter(refs: RefMap, name: string): RefSetter {
 * visit recursively the props and all the children to check if they are valid.
 * This is why it is only done in 'dev' mode.
 */
-export function validateProps<P>(name: string | ComponentConstructor<P>, props: P, parent?: any) {
+export function validateProps<P>(name: string | ComponentConstructor<P>, props: P, comp?: any) {
  const ComponentClass =
    typeof name !== "string"
      ? name
-      : (parent.constructor.components[name] as ComponentConstructor<P> | undefined);
+      : (comp.constructor.components[name] as ComponentConstructor<P> | undefined);

  if (!ComponentClass) {
    // this is an error, wrong component. We silently return here instead so the
@@ -221,7 +224,7 @@ export function validateProps<P>(name: string | ComponentConstructor<P>, props:

  const schema = ComponentClass.props;
  if (!schema) {
-    if (parent.__owl__.app.warnIfNoStaticProps) {
+    if (comp.__owl__.app.warnIfNoStaticProps) {
      console.warn(`Component '${ComponentClass.name}' does not have a static props description`);
    }
    return;
@@ -334,6 +334,57 @@ exports[`t-call (template calling) inherit context 2`] = `
 }"
 `;

+exports[`t-call (template calling) nested t-calls with magic variable 0 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { isBoundary, zero } = helpers;
+  const callTemplate_1 = app.getTemplate(\`grandchild\`);
+  const callTemplate_2 = app.getTemplate(\`child\`);
+  
+  let block1 = createBlock(\`<p>Some content...</p>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1;
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1;
+    const b1 = block1();
+    ctx[zero] = b1;
+    const b2 = callTemplate_1.call(this, ctx, node, key + \`__1\`);
+    ctx = ctx.__proto__;
+    ctx[zero] = b2;
+    return callTemplate_2.call(this, ctx, node, key + \`__2\`);
+  }
+}"
+`;
+
+exports[`t-call (template calling) nested t-calls with magic variable 0 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { zero } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = text(\`grandchild\`);
+    const b3 = ctx[zero];
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`t-call (template calling) nested t-calls with magic variable 0 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { zero } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return ctx[zero];
+  }
+}"
+`;
+
 exports[`t-call (template calling) recursive template, part 1 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -126,7 +126,7 @@ exports[`t-esc t-esc is escaped 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`var\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`var\`] = new LazyValue(value1, ctx, this, node, key);
    let txt1 = ctx['var'];
    return block1([txt1]);
  }
@@ -161,7 +161,7 @@ exports[`t-out t-out bdom 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`var\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`var\`] = new LazyValue(value1, ctx, this, node, key);
    const b3 = safeOutput(ctx['var']);
    return block1([], [b3]);
  }
@@ -310,7 +310,7 @@ exports[`t-out t-out switch markup on bdom 1`] = `
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
    let b3,b5;
-    ctx[\`bdom\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`bdom\`] = new LazyValue(value1, ctx, this, node, key);
    if (ctx['hasBdom']) {
      const b4 = safeOutput(ctx['bdom']);
      b3 = block3([], [b4]);
@@ -106,7 +106,7 @@ exports[`t-set set from body literal (with t-if/t-else 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`value\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`value\`] = new LazyValue(value1, ctx, this, node, key);
    return text(ctx['value']);
  }
 }"
@@ -142,7 +142,7 @@ exports[`t-set set from body lookup 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`stuff\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`stuff\`] = new LazyValue(value1, ctx, this, node, key);
    let txt1 = ctx['stuff'];
    return block1([txt1]);
  }
@@ -206,7 +206,7 @@ exports[`t-set t-set body is evaluated immediately 1`] = `
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
    setContextValue(ctx, \\"v1\\", 'before');
-    ctx[\`v2\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v2\`] = new LazyValue(value1, ctx, this, node, key);
    setContextValue(ctx, \\"v1\\", 'after');
    const b3 = safeOutput(ctx['v2']);
    return block1([], [b3]);
@@ -471,7 +471,7 @@ exports[`t-set t-set with content and sub t-esc 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`setvar\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`setvar\`] = new LazyValue(value1, ctx, this, node, key);
    let txt1 = ctx['setvar'];
    return block1([txt1]);
  }
@@ -497,7 +497,7 @@ exports[`t-set t-set with t-value (falsy) and body 1`] = `
    ctx[isBoundary] = 1
    setContextValue(ctx, \\"v3\\", false);
    setContextValue(ctx, \\"v1\\", 'before');
-    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, this, node));
+    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, this, node, key));
    setContextValue(ctx, \\"v1\\", 'after');
    setContextValue(ctx, \\"v3\\", true);
    const b3 = safeOutput(ctx['v2']);
@@ -525,7 +525,7 @@ exports[`t-set t-set with t-value (truthy) and body 1`] = `
    ctx[isBoundary] = 1
    setContextValue(ctx, \\"v3\\", 'Truthy');
    setContextValue(ctx, \\"v1\\", 'before');
-    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, this, node));
+    ctx[\`v2\`] = withDefault(ctx['v3'], new LazyValue(value1, ctx, this, node, key));
    setContextValue(ctx, \\"v1\\", 'after');
    setContextValue(ctx, \\"v3\\", false);
    const b3 = safeOutput(ctx['v2']);
@@ -638,7 +638,7 @@ exports[`t-set value priority (with non text body 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`value\`] = withDefault(1, new LazyValue(value1, ctx, this, node));
+    ctx[\`value\`] = withDefault(1, new LazyValue(value1, ctx, this, node, key));
    let txt1 = ctx['value'];
    return block1([txt1]);
  }
@@ -479,4 +479,21 @@ describe("t-call (template calling)", () => {
      "<span>123lucas</span>"
    );
  });
+
+  test("nested t-calls with magic variable 0", () => {
+    const context = new TestContext();
+    context.addTemplate("grandchild", `grandchild<t t-out="0"/>`);
+    context.addTemplate("child", `<t t-out="0"/>`);
+    context.addTemplate(
+      "main",
+      `
+        <t t-call="child">
+            <t t-call="grandchild">
+                <p>Some content...</p>
+            </t>
+        </t>`
+    );
+
+    expect(context.renderToString("main")).toBe("grandchild<p>Some content...</p>");
+  });
 });
@@ -20,7 +20,7 @@ exports[`basics display a nice error if it cannot find component (in dev mode) 1
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SomeMispelledComponent\`, props1, ctx);
+    helpers.validateProps(\`SomeMispelledComponent\`, props1, this);
    return comp1(props1, key + \`__1\`, node, this, null);
  }
 }"
@@ -58,6 +58,20 @@ exports[`event handling handler receive the event as argument 2`] = `
 }"
 `;

+exports[`event handling handler works when app is mounted in an iframe 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<span block-handler-0=\\"click\\">click me</span>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let hdlr1 = [ctx['inc'], ctx];
+    return block1([hdlr1]);
+  }
+}"
+`;
+
 exports[`event handling input blur event is not called if component is destroyed 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -704,7 +704,7 @@ exports[`lifecycle hooks timeout in onWillUpdateProps emits a warning 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {prop: ctx['state'].prop};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    return comp1(props1, key + \`__1\`, node, this, null);
  }
 }"
@@ -163,7 +163,7 @@ exports[`basics t-set with a body expression can be passed in props, and then t-
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`abc\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`abc\`] = new LazyValue(value1, ctx, this, node, key);
    const b3 = comp1({val: ctx['abc']}, key + \`__1\`, node, this, null);
    return block1([], [b3]);
  }
@@ -8,7 +8,7 @@ exports[`default props a default prop cannot be defined on a mandatory prop 1`]
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    return comp1(props1, key + \`__1\`, node, this, null);
  }
 }"
@@ -24,7 +24,7 @@ exports[`default props can set default boolean values 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -61,7 +61,7 @@ exports[`default props can set default values 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -92,7 +92,7 @@ exports[`default props default values are also set whenever component is updated
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['state'].p};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -121,7 +121,7 @@ exports[`props validation can specify that additional props are allowed (array)
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {message: 'm',otherProp: 'o'};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    return comp1(props1, key + \`__1\`, node, this, null);
  }
 }"
@@ -148,7 +148,7 @@ exports[`props validation can specify that additional props are allowed (object)
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {message: 'm',otherProp: 'o'};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    return comp1(props1, key + \`__1\`, node, this, null);
  }
 }"
@@ -177,7 +177,7 @@ exports[`props validation can validate a prop with multiple types 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -207,7 +207,7 @@ exports[`props validation can validate a prop with multiple types 3`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -237,7 +237,7 @@ exports[`props validation can validate a prop with multiple types 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -254,7 +254,7 @@ exports[`props validation can validate an array with given primitive type 1`] =
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -284,7 +284,7 @@ exports[`props validation can validate an array with given primitive type 3`] =
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -314,7 +314,7 @@ exports[`props validation can validate an array with given primitive type 5`] =
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -331,7 +331,7 @@ exports[`props validation can validate an array with given primitive type 6`] =
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -348,7 +348,7 @@ exports[`props validation can validate an array with multiple sub element types
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -378,7 +378,7 @@ exports[`props validation can validate an array with multiple sub element types
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -408,7 +408,7 @@ exports[`props validation can validate an array with multiple sub element types
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -438,7 +438,7 @@ exports[`props validation can validate an array with multiple sub element types
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -455,7 +455,7 @@ exports[`props validation can validate an object with simple shape 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -485,7 +485,7 @@ exports[`props validation can validate an object with simple shape 3`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -502,7 +502,7 @@ exports[`props validation can validate an object with simple shape 4`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -519,7 +519,7 @@ exports[`props validation can validate an object with simple shape 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -536,7 +536,7 @@ exports[`props validation can validate an optional props 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -566,7 +566,7 @@ exports[`props validation can validate an optional props 3`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -596,7 +596,7 @@ exports[`props validation can validate an optional props 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -613,7 +613,7 @@ exports[`props validation can validate recursively complicated prop def 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -643,7 +643,7 @@ exports[`props validation can validate recursively complicated prop def 3`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -673,13 +673,47 @@ exports[`props validation can validate recursively complicated prop def 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
 }"
 `;

+exports[`props validation can validate through slots 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  const comp2 = app.createComponent(\`Wrapper\`, true, true, false, true);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    const props1 = {};
+    helpers.validateProps(\`Child\`, props1, this);
+    return comp1(props1, key + \`__1\`, node, this, null);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const props2 = {slots: markRaw({'default': {__render: slot1, __ctx: ctx}})};
+    helpers.validateProps(\`Wrapper\`, props2, this);
+    return comp2(props2, key + \`__2\`, node, this, null);
+  }
+}"
+`;
+
+exports[`props validation can validate through slots 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return callSlot(ctx, node, key, 'default', false, {});
+  }
+}"
+`;
+
 exports[`props validation default values are applied before validating props at update 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -690,7 +724,7 @@ exports[`props validation default values are applied before validating props at
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['state'].p};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -721,7 +755,7 @@ exports[`props validation missing required boolean prop causes an error 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -738,7 +772,7 @@ exports[`props validation mix of optional and mandatory 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -755,7 +789,7 @@ exports[`props validation props are validated in dev mode (code snapshot) 1`] =
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {message: 1};
-    helpers.validateProps(\`Child\`, props1, ctx);
+    helpers.validateProps(\`Child\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -786,7 +820,7 @@ exports[`props validation props are validated whenever component is updated 1`]
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['state'].p};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -817,7 +851,7 @@ exports[`props validation props: list of strings 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -834,7 +868,7 @@ exports[`props validation validate simple types 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -851,7 +885,7 @@ exports[`props validation validate simple types 2`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -881,7 +915,7 @@ exports[`props validation validate simple types 4`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -898,7 +932,7 @@ exports[`props validation validate simple types 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -915,7 +949,7 @@ exports[`props validation validate simple types 6`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -945,7 +979,7 @@ exports[`props validation validate simple types 8`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -962,7 +996,7 @@ exports[`props validation validate simple types 9`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -979,7 +1013,7 @@ exports[`props validation validate simple types 10`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1009,7 +1043,7 @@ exports[`props validation validate simple types 12`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1026,7 +1060,7 @@ exports[`props validation validate simple types 13`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1043,7 +1077,7 @@ exports[`props validation validate simple types 14`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1073,7 +1107,7 @@ exports[`props validation validate simple types 16`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1090,7 +1124,7 @@ exports[`props validation validate simple types 17`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1107,7 +1141,7 @@ exports[`props validation validate simple types 18`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1137,7 +1171,7 @@ exports[`props validation validate simple types 20`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1154,7 +1188,7 @@ exports[`props validation validate simple types 21`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1171,7 +1205,7 @@ exports[`props validation validate simple types 22`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1201,7 +1235,7 @@ exports[`props validation validate simple types 24`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1218,7 +1252,7 @@ exports[`props validation validate simple types, alternate form 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1235,7 +1269,7 @@ exports[`props validation validate simple types, alternate form 2`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1265,7 +1299,7 @@ exports[`props validation validate simple types, alternate form 4`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1282,7 +1316,7 @@ exports[`props validation validate simple types, alternate form 5`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1299,7 +1333,7 @@ exports[`props validation validate simple types, alternate form 6`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1329,7 +1363,7 @@ exports[`props validation validate simple types, alternate form 8`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1346,7 +1380,7 @@ exports[`props validation validate simple types, alternate form 9`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1363,7 +1397,7 @@ exports[`props validation validate simple types, alternate form 10`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1393,7 +1427,7 @@ exports[`props validation validate simple types, alternate form 12`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1410,7 +1444,7 @@ exports[`props validation validate simple types, alternate form 13`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1427,7 +1461,7 @@ exports[`props validation validate simple types, alternate form 14`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1457,7 +1491,7 @@ exports[`props validation validate simple types, alternate form 16`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1474,7 +1508,7 @@ exports[`props validation validate simple types, alternate form 17`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1491,7 +1525,7 @@ exports[`props validation validate simple types, alternate form 18`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1521,7 +1555,7 @@ exports[`props validation validate simple types, alternate form 20`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1538,7 +1572,7 @@ exports[`props validation validate simple types, alternate form 21`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1555,7 +1589,7 @@ exports[`props validation validate simple types, alternate form 22`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1585,7 +1619,7 @@ exports[`props validation validate simple types, alternate form 24`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {p: ctx['p']};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -1602,7 +1636,7 @@ exports[`props validation validation is only done in dev mode 1`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const props1 = {};
-    helpers.validateProps(\`SubComp\`, props1, ctx);
+    helpers.validateProps(\`SubComp\`, props1, this);
    const b2 = comp1(props1, key + \`__1\`, node, this, null);
    return block1([], [b2]);
  }
@@ -604,6 +604,64 @@ exports[`slots default slot work with text nodes 2`] = `
 }"
 `;

+exports[`slots dynamic slot in multiple locations 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { capture, markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  const comp2 = app.createComponent(\`Slotter\`, true, true, false, false);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    const b2 = text(\`hello \`);
+    const b3 = comp1({}, key + \`__1\`, node, this, null);
+    return multi([b2, b3]);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return comp2({location: ctx['state'].location,slots: markRaw({'coffee': {__render: slot1, __ctx: ctx1}})}, key + \`__2\`, node, this, null);
+  }
+}"
+`;
+
+exports[`slots dynamic slot in multiple locations 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  let block2 = createBlock(\`<p><block-child-0/></p>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2,b4;
+    if (ctx['props'].location===1) {
+      const slot1 = ('coffee');
+      const b3 = toggler(slot1, callSlot(ctx, node, key + \`__1\`, slot1, true, {}));
+      b2 = block2([], [b3]);
+    }
+    if (ctx['props'].location===2) {
+      const slot2 = ('coffee');
+      b4 = toggler(slot2, callSlot(ctx, node, key + \`__2\`, slot2, true, {}));
+    }
+    return multi([b2, b4]);
+  }
+}"
+`;
+
+exports[`slots dynamic slot in multiple locations 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div>child</div>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
 exports[`slots dynamic t-slot call 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -645,7 +703,7 @@ exports[`slots dynamic t-slot call 2`] = `
  return function template(ctx, node, key = \\"\\") {
    let hdlr1 = [ctx['toggle'], ctx];
    const slot1 = (ctx['current'].slot);
-    const b2 = toggler(slot1, callSlot(ctx, node, key, slot1, true, {}));
+    const b2 = toggler(slot1, callSlot(ctx, node, key + \`__1\`, slot1, true, {}));
    return block1([hdlr1], [b2]);
  }
 }"
@@ -695,7 +753,7 @@ exports[`slots dynamic t-slot call with default 2`] = `
  
  return function template(ctx, node, key = \\"\\") {
    let hdlr1 = [ctx['toggle'], ctx];
-    const b3 = callSlot(ctx, node, key, (ctx['current'].slot), true, {}, defaultContent1);
+    const b3 = callSlot(ctx, node, key + \`__1\`, (ctx['current'].slot), true, {}, defaultContent1);
    return block1([hdlr1], [b3]);
  }
 }"
@@ -726,7 +784,7 @@ exports[`slots fun: two calls to the same slot 2`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const b2 = callSlot(ctx, node, key, 'default', false, {});
-    const b3 = callSlot(ctx, node, key, 'default', false, {});
+    const b3 = callSlot(ctx, node, key + \`__1\`, 'default', false, {});
    return multi([b2, b3]);
  }
 }"
@@ -1527,7 +1585,7 @@ exports[`slots simple dynamic slot with slot scope 2`] = `
  
  return function template(ctx, node, key = \\"\\") {
    const slot1 = ('slotName');
-    const b2 = toggler(slot1, callSlot(ctx, node, key, slot1, true, {bool: ctx['state'].bool}));
+    const b2 = toggler(slot1, callSlot(ctx, node, key + \`__1\`, slot1, true, {bool: ctx['state'].bool}));
    return block1([], [b2]);
  }
 }"
@@ -1854,7 +1912,7 @@ exports[`slots slot content has different key from other content -- dynamic slot
  return function template(ctx, node, key = \\"\\") {
    const b2 = comp1({parent: 'SlotDisplay'}, key + \`__1\`, node, this, null);
    const slot1 = (ctx['slotName']);
-    const b3 = toggler(slot1, callSlot(ctx, node, key, slot1, true, {}));
+    const b3 = toggler(slot1, callSlot(ctx, node, key + \`__2\`, slot1, true, {}));
    return multi([b2, b3]);
  }
 }"
@@ -1995,6 +2053,118 @@ exports[`slots slot content is bound to caller 2`] = `
 }"
 `;

+exports[`slots slot in multiple locations 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  const comp2 = app.createComponent(\`Slotter\`, true, true, false, false);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    const b2 = text(\` hello \`);
+    const b3 = comp1({}, key + \`__1\`, node, this, null);
+    return multi([b2, b3]);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    return comp2({location: ctx['state'].location,slots: markRaw({'default': {__render: slot1, __ctx: ctx}})}, key + \`__2\`, node, this, null);
+  }
+}"
+`;
+
+exports[`slots slot in multiple locations 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  let block2 = createBlock(\`<p><block-child-0/></p>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2,b4;
+    if (ctx['props'].location===1) {
+      const b3 = callSlot(ctx, node, key, 'default', false, {});
+      b2 = block2([], [b3]);
+    }
+    if (ctx['props'].location===2) {
+      b4 = callSlot(ctx, node, key + \`__1\`, 'default', false, {});
+    }
+    return multi([b2, b4]);
+  }
+}"
+`;
+
+exports[`slots slot in multiple locations 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div>child</div>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`slots slot in t-foreach locations 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  const comp2 = app.createComponent(\`Slotter\`, true, true, false, false);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    const b2 = text(\` hello \`);
+    const b3 = comp1({}, key + \`__1\`, node, this, null);
+    return multi([b2, b3]);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    return comp2({list: ctx['state'].list,slots: markRaw({'default': {__render: slot1, __ctx: ctx}})}, key + \`__2\`, node, this, null);
+  }
+}"
+`;
+
+exports[`slots slot in t-foreach locations 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, callSlot, withKey } = helpers;
+  
+  let block2 = createBlock(\`<p><block-text-0/><block-child-0/></p>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['props'].list);;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem_index\`] = i1;
+      const key1 = ctx['elem_index'];
+      let txt1 = ctx['elem'];
+      const b3 = callSlot(ctx, node, key1, 'default', false, {});
+      c_block1[i1] = withKey(block2([txt1], [b3]), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
+exports[`slots slot in t-foreach locations 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div>child</div>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
 exports[`slots slot preserves properly parented relationship 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -2665,6 +2835,36 @@ exports[`slots t-set t-value in a slot 2`] = `
 }"
 `;

+exports[`slots t-set-slot=default has priority over rest of the content 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { capture, markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, true, false, true);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    return text(\`some other text\`);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return comp1({slots: markRaw({'default': {__render: slot1, __ctx: ctx1}})}, key + \`__1\`, node, this, null);
+  }
+}"
+`;
+
+exports[`slots t-set-slot=default has priority over rest of the content 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { callSlot } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return callSlot(ctx, node, key, 'default', false, {});
+  }
+}"
+`;
+
 exports[`slots t-slot in recursive templates 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -444,6 +444,51 @@ exports[`t-call t-call with t-call-context and subcomponent 3`] = `
 }"
 `;

+exports[`t-call t-call with t-call-context and subcomponent, in dev mode 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const callTemplate_1 = app.getTemplate(\`someTemplate\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let ctx1 = ctx['subctx'];
+    return callTemplate_1.call(this, ctx1, node, key + \`__1\`);
+  }
+}"
+`;
+
+exports[`t-call t-call with t-call-context and subcomponent, in dev mode 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, false);
+  const comp2 = app.createComponent(\`Child\`, true, false, false, false);
+  
+  return function template(ctx, node, key = \\"\\") {
+    const props1 = {name: ctx['aab']};
+    helpers.validateProps(\`Child\`, props1, this);
+    const b2 = comp1(props1, key + \`__1\`, node, this, null);
+    const props2 = {name: ctx['lpe']};
+    helpers.validateProps(\`Child\`, props2, this);
+    const b3 = comp2(props2, key + \`__2\`, node, this, null);
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`t-call t-call with t-call-context and subcomponent, in dev mode 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = text(\`child\`);
+    const b3 = text(ctx['props'].name);
+    return multi([b2, b3]);
+  }
+}"
+`;
+
 exports[`t-call t-call with t-call-context, simple use 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -53,10 +53,10 @@ exports[`list of components crash on duplicate key in dev mode 1`] = `
    for (let i1 = 0; i1 < l_block1; i1++) {
      ctx[\`item\`] = v_block1[i1];
      const key1 = 'child';
-      if (keys1.has(key1)) { throw new OwlError(\`Got duplicate key in t-foreach: \${key1}\`)}
-      keys1.add(key1);
+      if (keys1.has(String(key1))) { throw new OwlError(\`Got duplicate key in t-foreach: \${key1}\`)}
+      keys1.add(String(key1));
      const props1 = {};
-      helpers.validateProps(\`Child\`, props1, ctx);
+      helpers.validateProps(\`Child\`, props1, this);
      c_block1[i1] = withKey(comp1(props1, key + \`__1__\${key1}\`, node, this, null), key1);
    }
    return list(c_block1);
@@ -75,6 +75,42 @@ exports[`list of components crash on duplicate key in dev mode 2`] = `
 }"
 `;

+exports[`list of components crash when using object as keys that serialize to the same string 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, OwlError, withKey } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList([{},{}]);;
+    const keys1 = new Set();
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`item\`] = v_block1[i1];
+      const key1 = ctx['item'];
+      if (keys1.has(String(key1))) { throw new OwlError(\`Got duplicate key in t-foreach: \${key1}\`)}
+      keys1.add(String(key1));
+      const props1 = {};
+      helpers.validateProps(\`Child\`, props1, this);
+      c_block1[i1] = withKey(comp1(props1, key + \`__1__\${key1}\`, node, this, null), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
+exports[`list of components crash when using object as keys that serialize to the same string 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`\`);
+  }
+}"
+`;
+
 exports[`list of components list of sub components inside other nodes 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -113,6 +149,58 @@ exports[`list of components list of sub components inside other nodes 2`] = `
 }"
 `;

+exports[`list of components order is correct when slots are not of same type 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { capture, markRaw } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, true, false, true);
+  
+  let block2 = createBlock(\`<div>A</div>\`);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    let b2;
+    if (!ctx['state'].active) {
+      b2 = block2();
+    }
+    return multi([b2]);
+  }
+  
+  function slot2(ctx, node, key = \\"\\") {
+    return text(\`B\`);
+  }
+  
+  function slot3(ctx, node, key = \\"\\") {
+    return text(\`C\`);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const ctx1 = capture(ctx);
+    return comp1({slots: markRaw({'a': {__render: slot1, __ctx: ctx1, active: !ctx['state'].active}, 'b': {__render: slot2, __ctx: ctx1, active: true}, 'c': {__render: slot3, __ctx: ctx1, active: ctx['state'].active}})}, key + \`__1\`, node, this, null);
+  }
+}"
+`;
+
+exports[`list of components order is correct when slots are not of same type 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, callSlot, withKey } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['slotNames']);;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`slotName\`] = v_block1[i1];
+      const key1 = ctx['slotName'];
+      const slot1 = (ctx['slotName']);
+      c_block1[i1] = withKey(toggler(slot1, callSlot(ctx, node, key1 + \`__1__\${key1}\`, slot1, true, {})), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
 exports[`list of components reconciliation alg works for t-foreach in t-foreach 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -0,0 +1,39 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`components in t-out simple list 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, isBoundary, withDefault, LazyValue, safeOutput, withKey } = helpers;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  
+  function value1(ctx, node, key = \\"\\") {
+    return comp1({}, key + \`__1\`, node, this, null);
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    ctx[isBoundary] = 1
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList([1,2]);;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`n\`] = v_block1[i1];
+      const key1 = ctx['n'];
+      ctx[\`blabla\`] = new LazyValue(value1, ctx, this, node, key1);
+      c_block1[i1] = withKey(safeOutput(ctx['blabla']), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
+exports[`components in t-out simple list 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`child\`);
+  }
+}"
+`;
@@ -59,7 +59,7 @@ exports[`t-set slots with a t-set with a component in body 1`] = `
  function slot1(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`v\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v\`] = new LazyValue(value1, ctx, this, node, key);
    const b3 = text(\` in slot \`);
    const b4 = safeOutput(ctx['v']);
    return multi([b3, b4]);
@@ -114,7 +114,7 @@ exports[`t-set slots with an t-set with a component in body 1`] = `
  function slot1(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`v\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v\`] = new LazyValue(value1, ctx, this, node, key);
    const b5 = text(\` tea \`);
    const b6 = safeOutput(ctx['v']);
    return multi([b5, b6]);
@@ -169,7 +169,7 @@ exports[`t-set slots with an unused t-set with a component in body 1`] = `
  function slot1(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`v\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v\`] = new LazyValue(value1, ctx, this, node, key);
    return text(\` in slot \`);
  }
  
@@ -343,7 +343,7 @@ exports[`t-set t-set with a component in body 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`v\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v\`] = new LazyValue(value1, ctx, this, node, key);
    const b3 = safeOutput(ctx['v']);
    return block1([], [b3]);
  }
@@ -377,7 +377,7 @@ exports[`t-set t-set with something in body 1`] = `
  return function template(ctx, node, key = \\"\\") {
    ctx = Object.create(ctx);
    ctx[isBoundary] = 1
-    ctx[\`v\`] = new LazyValue(value1, ctx, this, node);
+    ctx[\`v\`] = new LazyValue(value1, ctx, this, node, key);
    const b3 = safeOutput(ctx['v']);
    return block1([], [b3]);
  }
@@ -1,5 +1,12 @@
 import { App, Component, mount, status, toRaw, useState, xml } from "../../src";
-import { elem, makeTestFixture, nextTick, snapshotEverything, useLogLifecycle } from "../helpers";
+import {
+  elem,
+  makeTestFixture,
+  nextAppError,
+  nextTick,
+  snapshotEverything,
+  useLogLifecycle,
+} from "../helpers";
 import { markup } from "../../src/runtime/utils";

 let fixture: HTMLElement;
@@ -208,14 +215,14 @@ describe("basics", () => {
      static template = xml`<div/>`;
    }
    let error: Error;
-    const prom = mount(Test, fixture);
+    const app = new App(Test);
+    const prom = app.mount(fixture);
    await Promise.resolve();
    fixture.remove();
-    try {
-      await prom;
-    } catch (e) {
-      error = e as Error;
-    }
+    prom.catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Cannot mount a component on a detached dom node"
+    );
    expect(error!).toBeDefined();
    expect(error!.message).toBe("Cannot mount a component on a detached dom node");
    expect(console.warn).toBeCalledTimes(1);
@@ -1,4 +1,4 @@
-import { Component, mount, onWillDestroy } from "../../src";
+import { App, Component, mount, onWillDestroy } from "../../src";
 import {
  onError,
  onMounted,
@@ -18,6 +18,7 @@ import {
  nextMicroTick,
  snapshotEverything,
  useLogLifecycle,
+  nextAppError,
 } from "../helpers";
 import { OwlError } from "../../src/runtime/error_handling";

@@ -59,9 +60,10 @@ describe("basics", () => {
    parent.state.flag = true;

    parent.render();
-    await nextTick();
+    await expect(nextAppError(parent.__owl__.app)).resolves.toThrow(
+      "An error occured in the owl lifecycle"
+    );
    expect(fixture.innerHTML).toBe("");
-    expect(mockConsoleError).toBeCalledTimes(1);
    expect(mockConsoleWarn).toBeCalledTimes(1);
  });

@@ -71,12 +73,13 @@ describe("basics", () => {
      static template = xml`<SomeMispelledComponent />`;
      static components = { SomeComponent };
    }
+    const app = new App(Parent);
    let error: Error;
-    try {
-      await mount(Parent, fixture);
-    } catch (e) {
-      error = e as Error;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      'Cannot find the definition of component "SomeMispelledComponent"'
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe('Cannot find the definition of component "SomeMispelledComponent"');
    expect(console.error).toBeCalledTimes(0);
@@ -90,12 +93,13 @@ describe("basics", () => {
      static template = xml`<SomeMispelledComponent />`;
      static components = { SomeComponent };
    }
+    const app = new App(Parent, { test: true });
    let error: Error;
-    try {
-      await mount(Parent, fixture, { test: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      'Cannot find the definition of component "SomeMispelledComponent"'
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe('Cannot find the definition of component "SomeMispelledComponent"');
    expect(console.error).toBeCalledTimes(0);
@@ -109,13 +113,13 @@ describe("basics", () => {
      static template = xml`<SomeComponent />`;
      static components = { SomeComponent: notAComponentConstructor };
    }
+    const app = new App(Parent as typeof Component);
    let error: Error;
-    try {
-      // @ts-expect-error
-      await mount(Parent, fixture);
-    } catch (e) {
-      error = e as Error;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      '"SomeComponent" is not a Component. It must inherit from the Component class'
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      '"SomeComponent" is not a Component. It must inherit from the Component class'
@@ -156,16 +160,15 @@ describe("basics", () => {
 describe("errors and promises", () => {
  test("a rendering error will reject the mount promise", async () => {
    // we do not catch error in willPatch anymore
-    class App extends Component {
+    class Root extends Component {
      static template = xml`<div><t t-esc="this.will.crash"/></div>`;
    }

+    const app = new App(Root);
    let error: OwlError;
-    try {
-      await mount(App, fixture);
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    const regexp =
@@ -176,7 +179,7 @@ describe("errors and promises", () => {
  });

  test("an error in mounted call will reject the mount promise", async () => {
-    class App extends Component {
+    class Root extends Component {
      static template = xml`<div>abc</div>`;
      setup() {
        onMounted(() => {
@@ -185,12 +188,11 @@ describe("errors and promises", () => {
      }
    }

+    const app = new App(Root);
    let error: OwlError;
-    try {
-      await mount(App, fixture);
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    expect(error!.cause.message).toBe("boom");
@@ -200,7 +202,7 @@ describe("errors and promises", () => {
  });

  test("an error in onMounted callback will have the component's setup in its stack trace", async () => {
-    class App extends Component {
+    class Root extends Component {
      static template = xml`<div>abc</div>`;
      setup() {
        onMounted(() => {
@@ -209,14 +211,13 @@ describe("errors and promises", () => {
      }
    }

-    let error: Error;
-    try {
-      await mount(App, fixture, { test: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onMounted");
+    await mountProm;
    expect(error!).toBeDefined();
-    expect(error!.stack).toContain("App.setup");
+    expect(error!.stack).toContain("Root.setup");
    expect(error!.stack).toContain("error_handling.test.ts");
    expect(fixture.innerHTML).toBe("");
    expect(mockConsoleError).toBeCalledTimes(0);
@@ -224,7 +225,7 @@ describe("errors and promises", () => {
  });

  test("errors in onWillRender/onRender aren't wrapped more than once", async () => {
-    class App extends Component {
+    class Root extends Component {
      static template = xml`<div>abc</div>`;
      setup() {
        onWillRender(() => {
@@ -236,12 +237,11 @@ describe("errors and promises", () => {
      }
    }

-    let error: Error;
-    try {
-      await mount(App, fixture, { test: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onWillRender");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      `The following error occurred in onWillRender: "boom in onWillRender"`
@@ -278,12 +278,11 @@ describe("errors and promises", () => {
      }
    }

-    let error: any;
-    try {
-      await mount(Root, fixture, { test: true });
-    } catch (e) {
-      error = e;
-    }
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onWillStart");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      `The following error occurred in onWillStart: "boom in onWillStart"`
@@ -342,17 +341,16 @@ describe("errors and promises", () => {
    class Child extends Component {
      static template = xml`<div><t t-esc="this.will.crash"/></div>`;
    }
-    class App extends Component {
+    class Parent extends Component {
      static template = xml`<div><Child/></div>`;
      static components = { Child };
    }

+    const app = new App(Parent);
    let error: OwlError;
-    try {
-      await mount(App, fixture);
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    const regexp =
@@ -394,12 +392,11 @@ describe("errors and promises", () => {
      static components = { Child };
    }

+    const app = new App(Parent);
    let error: OwlError;
-    try {
-      await mount(Parent, fixture);
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    const regexp =
@@ -425,13 +422,12 @@ describe("errors and promises", () => {
      }
    }

-    try {
-      await mount(Example, fixture, { test: true });
-    } catch (e) {
-      expect((e as Error).message).toBe(
-        `The following error occurred in onMounted: "Error in mounted"`
-      );
-    }
+    const app = new App(Example, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onMounted");
+    await mountProm;
+    expect(error!.message).toBe(`The following error occurred in onMounted: "Error in mounted"`);
    // 1 additional error is logged because the destruction of the app causes
    // the onWillUnmount hook to be called and to fail
    expect(mockConsoleError).toBeCalledTimes(1);
@@ -448,9 +444,10 @@ describe("errors and promises", () => {

    root.state = "boom";
    root.render();
-    await nextTick();
+    await expect(nextAppError(root.__owl__.app)).resolves.toThrow(
+      "error occured in the owl lifecycle"
+    );
    expect(fixture.innerHTML).toBe("");
-    expect(mockConsoleError).toBeCalledTimes(1);
    expect(mockConsoleWarn).toBeCalledTimes(1);
  });
 });
@@ -500,13 +497,12 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: Error;
-    try {
-      await mount(Root, fixture, { test: true });
-    } catch (error) {
-      e = error as Error;
-    }
-    expect(e!.message).toBe(
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const crashProm = expect(nextAppError(app)).resolves.toThrow("error occurred in onWillStart");
+    await app.mount(fixture).catch((e: Error) => (error = e));
+    await crashProm;
+    expect(error!.message).toBe(
      `The following error occurred in onWillStart: "No active component (a hook function should only be called in 'setup')"`
    );
  });
@@ -523,14 +519,13 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture, { test: true });
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(`The following error occurred in onMounted: "test error"`);
-    expect(e!.cause).toBe(err);
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onMounted");
+    await mountProm;
+    expect(error!.message).toBe(`The following error occurred in onMounted: "test error"`);
+    expect(error!.cause).toBe(err);
  });

  test("Errors in owl lifecycle are wrapped in dev mode: async hook", async () => {
@@ -546,14 +541,13 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture, { test: true });
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(`The following error occurred in onWillStart: "test error"`);
-    expect(e!.cause).toBe(err);
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occurred in onWillStart");
+    await mountProm;
+    expect(error!.message).toBe(`The following error occurred in onWillStart: "test error"`);
+    expect(error!.cause).toBe(err);
  });

  test("Errors in owl lifecycle are wrapped outside dev mode: sync hook", async () => {
@@ -568,16 +562,15 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture);
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(
+    const app = new App(Root);
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
+    expect(error!.message).toBe(
      `An error occured in the owl lifecycle (see this Error's "cause" property)`
    );
-    expect(e!.cause).toBe(err);
+    expect(error!.cause).toBe(err);
  });

  test("Errors in owl lifecycle are wrapped out of dev mode: async hook", async () => {
@@ -593,16 +586,15 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture);
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(
+    const app = new App(Root);
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
+    expect(error!.message).toBe(
      `An error occured in the owl lifecycle (see this Error's "cause" property)`
    );
-    expect(e!.cause).toBe(err);
+    expect(error!.cause).toBe(err);
  });

  test("Thrown values that are not errors are wrapped in dev mode", async () => {
@@ -616,16 +608,15 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture, { test: true });
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(
+    const app = new App(Root, { test: true });
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("not an Error was thrown in onMounted");
+    await mountProm;
+    expect(error!.message).toBe(
      `Something that is not an Error was thrown in onMounted (see this Error's "cause" property)`
    );
-    expect(e!.cause).toBe("This is not an error");
+    expect(error!.cause).toBe("This is not an error");
  });

  test("Thrown values that are not errors are wrapped outside dev mode", async () => {
@@ -639,16 +630,15 @@ describe("can catch errors", () => {
        });
      }
    }
-    let e: OwlError;
-    try {
-      await mount(Root, fixture);
-    } catch (error) {
-      e = error as OwlError;
-    }
-    expect(e!.message).toBe(
+    const app = new App(Root);
+    let error: OwlError;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
+    expect(error!.message).toBe(
      `An error occured in the owl lifecycle (see this Error's "cause" property)`
    );
-    expect(e!.cause).toBe("This is not an error");
+    expect(error!.cause).toBe("This is not an error");
  });

  test("can catch an error in the initial call of a component render function (parent mounted)", async () => {
@@ -171,4 +171,22 @@ describe("event handling", () => {
    // input is removed when component is destroyed => nothing should happen
    expect([]).toBeLogged();
  });
+
+  test("handler works when app is mounted in an iframe", async () => {
+    let clickCount = 0;
+
+    class Parent extends Component {
+      static template = xml`<span t-on-click="inc">click me</span>`;
+      inc() {
+        clickCount++;
+      }
+    }
+    const iframe = document.createElement("iframe");
+    fixture.appendChild(iframe);
+    const iframeDoc = iframe.contentDocument!;
+    await mount(Parent, iframeDoc.body);
+    expect(clickCount).toBe(0);
+    iframeDoc.querySelector("span")!.click();
+    expect(clickCount).toBe(1);
+  });
 });
@@ -17,8 +17,16 @@ import {
  useChildSubEnv,
  useSubEnv,
  xml,
+  OwlError,
 } from "../../src/index";
-import { elem, logStep, makeTestFixture, nextTick, snapshotEverything } from "../helpers";
+import {
+  elem,
+  logStep,
+  makeTestFixture,
+  nextAppError,
+  nextTick,
+  snapshotEverything,
+} from "../helpers";

 let fixture: HTMLElement;

@@ -650,11 +658,12 @@ describe("hooks", () => {
        }
      }

-      try {
-        await mount(MyComponent, fixture);
-      } catch (e: any) {
-        expect(e.cause.message).toBe("Intentional error");
-      }
+      let error: OwlError;
+      const app = new App(MyComponent);
+      const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+      await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+      await mountProm;
+      expect(error!.cause.message).toBe("Intentional error");
      // no console.error because the error has been caught in this test
      expect(console.error).toHaveBeenCalledTimes(0);
      console.error = originalconsoleError;
@@ -1,6 +1,6 @@
-import { makeTestFixture, nextTick, snapshotEverything } from "../helpers";
-import { Component, onError, xml, mount } from "../../src";
-import { DEV_MSG } from "../../src/runtime/app";
+import { makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";
+import { Component, onError, xml, mount, OwlError } from "../../src";
+import { App, DEV_MSG } from "../../src/runtime/app";
 import { validateProps } from "../../src/runtime/template_helpers";
 import { Schema } from "../../src/runtime/validation";

@@ -48,13 +48,14 @@ describe("props validation", () => {
      static components = { SubComp };
      static template = xml`<div><SubComp /></div>`;
    }
-    let error: Error | undefined;

-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent, { test: true });
+    let error: OwlError | undefined;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Invalid props for component 'SubComp': 'message' is missing"
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe("Invalid props for component 'SubComp': 'message' is missing");
    error = undefined;
@@ -77,12 +78,13 @@ describe("props validation", () => {
      static template = xml`<div><SubComp /></div>`;
    }

-    let error: Error;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent, { test: true });
+    let error: OwlError | undefined;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Invalid props for component 'SubComp': 'message' is missing"
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe("Invalid props for component 'SubComp': 'message' is missing");
  });
@@ -126,14 +128,12 @@ describe("props validation", () => {
      };
      (Parent as any).components = { SubComp };

-      let error: Error | undefined;
      props = {};
-
-      try {
-        await mount(Parent, fixture, { dev: true });
-      } catch (e) {
-        error = e as Error;
-      }
+      let app = new App(Parent, { test: true });
+      let error: OwlError | undefined;
+      let mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+      await expect(nextAppError(app)).resolves.toThrow("Invalid props for component '_a'");
+      await mountProm;
      expect(error!).toBeDefined();
      expect(error!.message).toBe(
        `Invalid props for component '_a': 'p' is undefined (should be a ${test.type.name.toLowerCase()})`
@@ -147,11 +147,10 @@ describe("props validation", () => {
      }
      expect(error!).toBeUndefined();
      props = { p: test.ko };
-      try {
-        await mount(Parent, fixture, { dev: true });
-      } catch (e) {
-        error = e as Error;
-      }
+      app = new App(Parent, { test: true });
+      mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+      await expect(nextAppError(app)).resolves.toThrow("Invalid props for component '_a'");
+      await mountProm;
      expect(error!).toBeDefined();
      expect(error!.message).toBe(
        `Invalid props for component '_a': 'p' is not a ${test.type.name.toLowerCase()}`
@@ -181,13 +180,12 @@ describe("props validation", () => {
        static template = xml`<div>hey</div>`;
      };
      (Parent as any).components = { SubComp };
-      let error: Error | undefined;
      props = {};
-      try {
-        await mount(Parent, fixture, { dev: true });
-      } catch (e) {
-        error = e as Error;
-      }
+      let app = new App(Parent, { test: true });
+      let error: OwlError | undefined;
+      let mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+      await expect(nextAppError(app)).resolves.toThrow("Invalid props for component '_a'");
+      await mountProm;
      expect(error!).toBeDefined();
      expect(error!.message).toBe(
        `Invalid props for component '_a': 'p' is undefined (should be a ${test.type.name.toLowerCase()})`
@@ -201,11 +199,10 @@ describe("props validation", () => {
      }
      expect(error!).toBeUndefined();
      props = { p: test.ko };
-      try {
-        await mount(Parent, fixture, { dev: true });
-      } catch (e) {
-        error = e as Error;
-      }
+      app = new App(Parent, { test: true });
+      mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+      await expect(nextAppError(app)).resolves.toThrow("Invalid props for component '_a'");
+      await mountProm;
      expect(error!).toBeDefined();
      expect(error!.message).toBe(
        `Invalid props for component '_a': 'p' is not a ${test.type.name.toLowerCase()}`
@@ -227,26 +224,25 @@ describe("props validation", () => {
    }
    let error: Error;
    let props: { p?: any };
+    props = { p: "string" };
    try {
-      props = { p: "string" };
      await mount(Parent, fixture, { dev: true });
    } catch (e) {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
+    props = { p: true };
    try {
-      props = { p: true };
      await mount(Parent, fixture, { dev: true });
    } catch (e) {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: 1 };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: 1 };
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p' is not a string or boolean"
@@ -267,26 +263,25 @@ describe("props validation", () => {
    }
    let error: Error;
    let props: { p?: any };
+    props = { p: "key" };
    try {
-      props = { p: "key" };
      await mount(Parent, fixture, { dev: true });
    } catch (e) {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
+    props = {};
    try {
-      props = {};
      await mount(Parent, fixture, { dev: true });
    } catch (e) {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: 1 };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: 1 };
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe("Invalid props for component 'SubComp': 'p' is not a string");
  });
@@ -319,20 +314,18 @@ describe("props validation", () => {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: [1] };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: [1] };
+    let app = new App(Parent, { test: true });
+    let mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    error = undefined;
-    try {
-      props = { p: ["string", 1] };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    app = new App(Parent, { test: true });
+    mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
+    expect(error!).toBeDefined();
  });

  test("can validate an array with multiple sub element types", async () => {
@@ -370,12 +363,11 @@ describe("props validation", () => {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: [true, 1] };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: [true, 1] };
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p[1]' is not a string or boolean"
@@ -405,33 +397,30 @@ describe("props validation", () => {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: { id: 1, url: "url", extra: true } };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: { id: 1, url: "url", extra: true } };
+    let app = new App(Parent, { test: true });
+    let mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p' has not the correct shape (unknown key 'extra')"
    );
-    try {
-      props = { p: { id: "1", url: "url" } };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: { id: "1", url: "url" } };
+    app = new App(Parent, { test: true });
+    mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p' has not the correct shape ('id' is not a number)"
    );
    error = undefined;
-    try {
-      props = { p: { id: 1 } };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: { id: 1 } };
+    app = new App(Parent, { test: true });
+    mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p' has not the correct shape ('url' is missing (should be a string))"
@@ -474,12 +463,11 @@ describe("props validation", () => {
      error = e as Error;
    }
    expect(error!).toBeUndefined();
-    try {
-      props = { p: { id: 1, url: [12, true] } };
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    props = { p: { id: 1, url: [12, true] } };
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'SubComp': 'p' has not the correct shape ('url' is not a boolean or list of numbers)"
@@ -686,11 +674,10 @@ describe("props validation", () => {
      static components = { SubComp };
    }
    let error: Error;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'SubComp'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe("Invalid props for component 'SubComp': 'p' is missing");
  });
@@ -754,11 +741,10 @@ describe("props validation", () => {
      static template = xml`<div><Child/></div>`;
    }
    let error: Error;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("Invalid props for component 'Child'");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "Invalid props for component 'Child': 'mandatory' is missing (should be a number)"
@@ -794,6 +780,32 @@ describe("props validation", () => {
    // we just check that it doesn't throw
    await expect(mount(Parent, fixture, { dev: true })).resolves.toEqual(expect.anything());
  });
+
+  test("can validate through slots", async () => {
+    class Child extends Component {
+      static props = ["message"];
+      static template = xml`<div>hey</div>`;
+    }
+
+    class Wrapper extends Component {
+      static template = xml`<t t-slot="default"/>`;
+    }
+
+    class Parent extends Component {
+      static components = { Child, Wrapper };
+      static template = xml`<Wrapper><Child /></Wrapper>`;
+    }
+
+    const app = new App(Parent, { test: true });
+    let error: OwlError | undefined;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Invalid props for component 'Child': 'message' is missing"
+    );
+    await mountProm;
+    expect(error!).toBeDefined();
+    expect(error!.message).toBe("Invalid props for component 'Child': 'message' is missing");
+  });
 });

 //------------------------------------------------------------------------------
@@ -859,11 +871,12 @@ describe("default props", () => {
      static template = xml`<Child/>`;
    }
    let error: Error;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent, { test: true });
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(
+      "default value cannot be defined for a mandatory prop"
+    );
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(
      "A default value cannot be defined for a mandatory prop (name: 'mandatory', component: Child)"
@@ -1,5 +1,5 @@
-import { Component, mount, onMounted, useRef, useState } from "../../src/index";
-import { logStep, makeTestFixture, nextTick, snapshotEverything } from "../helpers";
+import { App, Component, mount, onMounted, useRef, useState } from "../../src/index";
+import { logStep, makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";
 import { xml } from "../../src/index";

 snapshotEverything();
@@ -94,9 +94,14 @@ describe("refs", () => {
      ref = useRef("coucou");
    }

-    await expect(async () => {
-      await mount(Test, fixture);
-    }).rejects.toThrowError("Cannot have 2 elements with same ref name at the same time");
+    const app = new App(Test, { test: true });
+    const mountProm = expect(app.mount(fixture)).rejects.toThrowError(
+      "Cannot have 2 elements with same ref name at the same time"
+    );
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Cannot have 2 elements with same ref name at the same time"
+    );
+    await mountProm;
    expect(console.warn).toBeCalledTimes(1);
    console.warn = consoleWarn;
  });
@@ -1,5 +1,5 @@
 import { App, Component, mount, onMounted, useState, xml } from "../../src/index";
-import { children, makeTestFixture, nextTick, snapshotEverything } from "../helpers";
+import { children, makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";

 snapshotEverything();
 let originalconsoleWarn = console.warn;
@@ -45,6 +45,23 @@ describe("slots", () => {
    expect(fixture.innerHTML).toBe("some text");
  });

+  test("t-set-slot=default has priority over rest of the content", async () => {
+    class Child extends Component {
+      static template = xml`<t t-slot="default"/>`;
+    }
+
+    class Parent extends Component {
+      static template = xml`<Child>
+        some text
+        <t t-set-slot="default">some other text</t>
+      </Child>`;
+      static components = { Child };
+    }
+    await mount(Parent, fixture);
+
+    expect(fixture.innerHTML).toBe("some other text");
+  });
+
  test("simple slot with slot scope", async () => {
    let child: any;
    class Child extends Component {
@@ -204,13 +221,12 @@ describe("slots", () => {
      static components = { Child };
    }

-    let error = null;
-    try {
-      await mount(Parent, fixture);
-    } catch (e) {
-      error = e;
-    }
-    expect(error).not.toBeNull();
+    let error: Error;
+    const app = new App(Parent);
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
+    expect(error!).not.toBeNull();
    expect(mockConsoleWarn).toBeCalledTimes(1);
  });

@@ -1819,4 +1835,102 @@ describe("slots", () => {
    await nextTick();
    expect(fixture.innerHTML).toBe("<button>inc</button>[B][C][A][sub1] [sub2334]");
  });
+
+  test("slot in multiple locations", async () => {
+    class Child extends Component {
+      static template = xml`<div>child</div>`;
+    }
+
+    class Slotter extends Component {
+      static components = { Child };
+      static template = xml`
+          <t t-if="props.location === 1">
+            <p><t t-slot="default"/></p>
+          </t>
+          <t t-if="props.location === 2">
+            <t t-slot="default"/>
+          </t>
+      `;
+    }
+
+    class Parent extends Component {
+      static components = { Child, Slotter };
+      static template = xml`
+         <Slotter location="state.location">
+          hello <Child/>
+         </Slotter>`;
+      state = useState({ location: 1 });
+    }
+
+    const parent = await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe("<p> hello <div>child</div></p>");
+    parent.state.location = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe(" hello <div>child</div>");
+  });
+
+  test("dynamic slot in multiple locations", async () => {
+    class Child extends Component {
+      static template = xml`<div>child</div>`;
+    }
+
+    class Slotter extends Component {
+      static components = { Child };
+      static template = xml`
+          <t t-if="props.location === 1">
+            <p><t t-slot="{{'coffee'}}"/></p>
+          </t>
+          <t t-if="props.location === 2">
+            <t t-slot="{{'coffee'}}"/>
+          </t>
+      `;
+    }
+
+    class Parent extends Component {
+      static components = { Child, Slotter };
+      static template = xml`
+         <Slotter location="state.location">
+          <t t-set-slot="coffee">hello <Child/></t>
+         </Slotter>`;
+      state = useState({ location: 1 });
+    }
+
+    const parent = await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe("<p>hello <div>child</div></p>");
+    parent.state.location = 2;
+    await nextTick();
+    expect(fixture.innerHTML).toBe("hello <div>child</div>");
+  });
+
+  test("slot in t-foreach locations", async () => {
+    class Child extends Component {
+      static template = xml`<div>child</div>`;
+    }
+
+    class Slotter extends Component {
+      static components = { Child };
+      static template = xml`
+          <t t-foreach="props.list" t-as="elem" t-key="elem_index">
+            <p><t t-esc="elem"/><t t-slot="default"/></p>
+          </t>
+      `;
+    }
+
+    class Parent extends Component {
+      static components = { Child, Slotter };
+      static template = xml`
+         <Slotter list="state.list">
+          hello <Child/>
+         </Slotter>`;
+      state = useState({ list: [1] });
+    }
+
+    const parent = await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe("<p>1 hello <div>child</div></p>");
+    parent.state.list.push(2);
+    await nextTick();
+    expect(fixture.innerHTML).toBe(
+      "<p>1 hello <div>child</div></p><p>2 hello <div>child</div></p>"
+    );
+  });
 });
@@ -1,6 +1,6 @@
 import { OwlError } from "../../src/runtime/error_handling";
-import { Component, mount, onMounted, useState, xml } from "../../src";
-import { makeTestFixture, nextTick, snapshotEverything } from "../helpers";
+import { App, Component, mount, onMounted, useState, xml } from "../../src";
+import { makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";

 snapshotEverything();
 let fixture: HTMLElement;
@@ -343,16 +343,15 @@ describe("style and class handling", () => {
    class Child extends Component {
      static template = xml`<div t-att-class="props.class" t-esc="this.will.crash"/>`;
    }
-    class ParentWidget extends Component {
+    class Parent extends Component {
      static template = xml`<Child class="'a'"/>`;
      static components = { Child };
    }
    let error: OwlError;
-    try {
-      await mount(ParentWidget, fixture);
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const app = new App(Parent);
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    const regexp =
@@ -287,4 +287,32 @@ describe("t-call", () => {
    });
    expect(fixture.innerHTML).toBe("childaaronchildlucas");
  });
+
+  test("t-call with t-call-context and subcomponent, in dev mode", async () => {
+    class Child extends Component {
+      static template = xml`child<t t-esc="props.name"/>`;
+      static props = ["name"];
+    }
+
+    class Root extends Component {
+      static template = xml`
+          <t t-call="someTemplate" t-call-context="subctx"/>`;
+
+      static components = { Child };
+
+      subctx = { aab: "aaron", lpe: "lucas" };
+    }
+
+    await mount(Root, fixture, {
+      dev: true,
+      templates: `
+        <templates>
+          <t t-name="someTemplate">
+            <Child name="aab"/>
+            <Child name="lpe"/>
+          </t>
+        </templates>`,
+    });
+    expect(fixture.innerHTML).toBe("childaaronchildlucas");
+  });
 });
@@ -1,5 +1,11 @@
-import { Component, mount, onMounted, useState, xml } from "../../src/index";
-import { makeTestFixture, nextTick, snapshotEverything, useLogLifecycle } from "../helpers";
+import { App, Component, mount, onMounted, useState, xml } from "../../src/index";
+import {
+  makeTestFixture,
+  nextAppError,
+  nextTick,
+  snapshotEverything,
+  useLogLifecycle,
+} from "../helpers";

 snapshotEverything();

@@ -315,10 +321,73 @@ describe("list of components", () => {
      `;
      static components = { Child };
    }
-    await expect(async () => {
-      await mount(Parent, fixture, { dev: true });
-    }).rejects.toThrowError("Got duplicate key in t-foreach: child");
+
+    const app = new App(Parent, { test: true });
+    const mountProm = expect(app.mount(fixture)).rejects.toThrow(
+      "Got duplicate key in t-foreach: child"
+    );
+    await expect(nextAppError(app)).resolves.toThrow("Got duplicate key in t-foreach: child");
+    await mountProm;
    console.info = consoleInfo;
    expect(mockConsoleWarn).toBeCalledTimes(1);
  });
+
+  test("crash when using object as keys that serialize to the same string", async () => {
+    const consoleInfo = console.info;
+    console.info = jest.fn();
+    class Child extends Component {
+      static template = xml``;
+    }
+
+    class Parent extends Component {
+      static template = xml`
+        <t t-foreach="[{}, {}]" t-as="item" t-key="item">
+          <Child/>
+        </t>
+      `;
+      static components = { Child };
+    }
+
+    const app = new App(Parent, { test: true });
+    const mountProm = expect(app.mount(fixture)).rejects.toThrow(
+      "Got duplicate key in t-foreach: [object Object]"
+    );
+    await expect(nextAppError(app)).resolves.toThrow(
+      "Got duplicate key in t-foreach: [object Object]"
+    );
+    await mountProm;
+    console.info = consoleInfo;
+    expect(mockConsoleWarn).toBeCalledTimes(1);
+  });
+
+  test("order is correct when slots are not of same type", async () => {
+    class Child extends Component {
+      static template = xml`
+          <t t-slot="{{ slotName }}" t-foreach="slotNames" t-as="slotName" t-key="slotName"/>
+      `;
+      get slotNames() {
+        return Object.entries(this.props.slots)
+          .filter((entry: any) => entry[1].active)
+          .map((entry) => entry[0]);
+      }
+    }
+
+    class Parent extends Component {
+      static template = xml`
+        <Child>
+          <t t-set-slot="a" active="!state.active"><div t-if="!state.active">A</div></t>
+          <t t-set-slot="b" active="true">B</t>
+          <t t-set-slot="c" active="state.active">C</t>
+        </Child>
+      `;
+      static components = { Child };
+      state = useState({ active: false });
+    }
+
+    const parent = await mount(Parent, fixture);
+    expect(fixture.textContent).toBe("AB");
+    parent.state.active = true;
+    await nextTick();
+    expect(fixture.textContent).toBe("BC");
+  });
 });
@@ -0,0 +1,36 @@
+import { Component, mount, xml } from "../../src/index";
+import { makeTestFixture, snapshotEverything } from "../helpers";
+
+snapshotEverything();
+
+// -----------------------------------------------------------------------------
+// t-out
+// -----------------------------------------------------------------------------
+
+describe("components in t-out", () => {
+  let fixture: HTMLElement;
+
+  beforeEach(() => {
+    fixture = makeTestFixture();
+  });
+
+  test("simple list", async () => {
+    class Child extends Component {
+      static template = xml`child`;
+    }
+
+    class Parent extends Component {
+      static template = xml`
+                <t t-foreach="[1,2]" t-as="n" t-key="n">
+                  <t t-set="blabla">
+                    <Child />
+                  </t>
+                  <t t-out="blabla"/>
+                </t>`;
+      static components = { Child };
+    }
+
+    await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe("childchild");
+  });
+});
@@ -261,6 +261,20 @@ expect.extend({
  },
 });

+export function nextAppError(app: any) {
+  const { handleError } = app;
+  return new Promise((resolve) => {
+    app.handleError = (...args: Parameters<typeof handleError>) => {
+      try {
+        handleError.call(app, ...args);
+      } catch (e: any) {
+        app.handleError = handleError;
+        resolve(e);
+      }
+    };
+  });
+}
+
 declare global {
  namespace jest {
    interface Matchers<R> {
@@ -155,6 +155,44 @@ exports[`Portal Add and remove portals with t-foreach inside div 1`] = `
 }"
 `;

+exports[`Portal Child and Portal 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  
+  let block3 = createBlock(\`<div class=\\"portal\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
+    const b3 = block3();
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`Portal Child and Portal 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const Portal = app.Portal;
+  const comp1 = app.createComponent(null, false, true, false, false);
+  
+  let block2 = createBlock(\`<span>child</span>\`);
+  let block3 = createBlock(\`<span>portal</span>\`);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    return block3();
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = block2();
+    const b4 = comp1({target: '.portal',slots: {'default': {__render: slot1, __ctx: ctx}}}, key + \`__1\`, node, ctx, Portal);
+    return multi([b2, b4]);
+  }
+}"
+`;
+
 exports[`Portal Portal composed with t-slot 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -515,6 +553,44 @@ exports[`Portal lifecycle hooks of portal sub component are properly called 2`]
 }"
 `;

+exports[`Portal portal and Child 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, true);
+  
+  let block2 = createBlock(\`<div class=\\"portal\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = block2();
+    const b3 = comp1({}, key + \`__1\`, node, this, null);
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`Portal portal and Child 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const Portal = app.Portal;
+  const comp1 = app.createComponent(null, false, true, false, false);
+  
+  let block2 = createBlock(\`<span>child</span>\`);
+  let block3 = createBlock(\`<span>portal</span>\`);
+  
+  function slot1(ctx, node, key = \\"\\") {
+    return block3();
+  }
+  
+  return function template(ctx, node, key = \\"\\") {
+    const b2 = block2();
+    const b4 = comp1({target: '.portal',slots: {'default': {__render: slot1, __ctx: ctx}}}, key + \`__1\`, node, ctx, Portal);
+    return multi([b2, b4]);
+  }
+}"
+`;
+
 exports[`Portal portal could have dynamically no content 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -12,7 +12,7 @@ import {
 } from "../../src";
 import { xml } from "../../src/";
 import { DEV_MSG } from "../../src/runtime/app";
-import { elem, makeTestFixture, nextTick, snapshotEverything } from "../helpers";
+import { elem, makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";

 let fixture: HTMLElement;
 let originalconsoleWarn = console.warn;
@@ -269,15 +269,14 @@ describe("Portal", () => {
    }

    let error: Error;
-    try {
-      await mount(Parent, fixture);
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent);
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("invalid portal target");
+    await mountProm;

    expect(error!).toBeDefined();
    expect(error!.message).toBe("invalid portal target");
-    expect(fixture.innerHTML).toBe(`<div></div>`);
+    expect(fixture.innerHTML).toBe(``);
    expect(mockConsoleWarn).toBeCalledTimes(1);
  });

@@ -875,6 +874,48 @@ describe("Portal", () => {
    await nextTick();
    expect(fixture.innerHTML).toBe('<div id="outside"></div><div></div>');
  });
+
+  test("Child and Portal", async () => {
+    class Child extends Component {
+      static template = xml`
+        <span>child</span>
+        <t t-portal="'.portal'"><span>portal</span></t>`;
+    }
+    class Parent extends Component {
+      static template = xml`
+        <t>
+          <Child/>
+          <div class="portal"></div>
+        </t>`;
+
+      static components = { Child };
+    }
+    await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe(
+      '<span>child</span><div class="portal"><span>portal</span></div>'
+    );
+  });
+
+  test("portal and Child", async () => {
+    class Child extends Component {
+      static template = xml`
+        <span>child</span>
+        <t t-portal="'.portal'"><span>portal</span></t>`;
+    }
+    class Parent extends Component {
+      static template = xml`
+        <t>
+          <div class="portal"></div>
+          <Child/>
+        </t>`;
+
+      static components = { Child };
+    }
+    await mount(Parent, fixture);
+    expect(fixture.innerHTML).toBe(
+      '<div class="portal"><span>portal</span></div><span>child</span>'
+    );
+  });
 });

 describe("Portal: UI/UX", () => {
@@ -960,11 +1001,10 @@ describe("Portal: Props validation", () => {
        </div>`;
    }
    let error: OwlError;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as OwlError;
-    }
+    const app = new App(Parent);
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("error occured in the owl lifecycle");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.cause).toBeDefined();
    expect(error!.cause.message).toBe(`' ' is not a valid selector`);
@@ -980,11 +1020,10 @@ describe("Portal: Props validation", () => {
        </div>`;
    }
    let error: Error;
-    try {
-      await mount(Parent, fixture, { dev: true });
-    } catch (e) {
-      error = e as Error;
-    }
+    const app = new App(Parent);
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow("invalid portal target");
+    await mountProm;
    expect(error!).toBeDefined();
    expect(error!.message).toBe(`invalid portal target`);
  });
@@ -72,10 +72,8 @@ async function startRelease() {
  }

  // ---------------------------------------------------------------------------
-  log(`Step 3/${STEPS}: updating package.json, readme.md and roadmap.md...`);
+  log(`Step 3/${STEPS}: updating package.json...`);
  await replaceInFile("./package.json", current, next);
-  await replaceInFile("./README.md", current, next);
-  await replaceInFile("./roadmap.md", current, next);

  // ---------------------------------------------------------------------------
  log(`Step 4/${STEPS}: creating git commit...`);
Author	SHA1	Message	Date
Samuel Degueldre	b2cfefd008	[FIX] portal: correctly mount portal content in target created by mount Previously, blah blah blah	2022-10-19 14:39:44 +02:00
Samuel Degueldre	30d6994836	[FIX] blockdom: correctly reorder children in heterogeneous t-foreach Currently, the `moveBefore` method on VNodes assumes that the `other` VNode it receives is of the same type, and that the entire VNode tree below that other VNode has the exact same structure. While this is correct in most cases, it breaks down when there is a VToggler somewhere in the VNode tree, as the structure below a VToggler can be very different from the structure below another VToggler that was created from the same compiled code. For example, two iterations of a t-foreach that contains a <t t-component="..."/> may spawn different components, and different components obviously have different structures. One way to fix this is to remove the assumption that the structure of the `this` block tree in moveBefore is the same as the structure of the `other` block tree, and instead, always give the concrete DOM node before which we want to move the current VNode instead of giving it a VNode and an afterNode as a fallback. One problem with this solution is that it degrades performance in the "standard" case, where a t-foreach contains no VToggler anywhere in its block tree, as retrieving the first concrete DOM node requires calling firstNode() which recursively traverses the entire tree. To avoid this performance penalty in the standard case, we opt to only go down this route whenever we encounter a VToggler when calling `moveBefore`. This requires that we maintain two separate methods, one to move a VNode before another VNode of assumed similar structure, which is basically the current implementation of `moveBefore` for all VNode types except VToggler, and one implementation that moves a VNode before a concrete DOM node. This method needs to be implemented for all VNode types, as all VNode types can be descendants of a VToggler. This method will only be called from one place: the `moveBeforeVNode` method of the toggler, which is the point where we realize that the assumption of identical structure breaks down. Co-authored-by: Bruno Boi <boi@odoo.com>	2022-10-19 13:11:44 +02:00
Samuel Degueldre	ba1a270c93	[FIX] parser: give t-set-slot="default" priority over the content Currently, if a component has a default slot defined with t-set-slot, and also content that compiles to something (eg, text or even a comment node), the content takes priority over the t-set-slot. As t-set-slot is more explicity, it should have priority.	2022-10-10 20:33:18 +02:00
Samuel Degueldre	d546244fc3	[FIX] runtime: correctly throw an error for duplicate object keys Currently when checking for duplicate keys, we insert the value of the key as is in a set then check for unicity against those. When the key is an object, we check for duplicates based on object identity, whereas the keys are used by owl as strings, and so using objects can cause duplicate key errors that do not throw correctly but crash in the owl internals. This commit fixes that by making the duplicate checking code serialize the key to string before insertion and when comparing against existing keys.	2022-10-10 13:53:11 +02:00
Géry Debongnie	a1f22829c1	[REL] v2.0.0 # v2.0.0 Finally the official v2.0.0 release is ready. There are no feature nor fixes since last beta release, because it is stable. Thank you to everyone who contributed. ## Changelog Owl 2.0 is a large improvement over 1.0. It brings a lot of new features, improvements, and better APIs. The most important changes are: - a completely overhauled slot API (in particular slot scopes, ...) - a new reactivity system, similar to Vue. In particular, if props are equals, then a sub component is not updated. - new rendering engine, based on blockdom. This makes Owl much faster - support for fragments: a template can have an arbitrary number of roots A detailed changelog can be found [here](CHANGELOG.md).	2022-10-07 15:27:58 +02:00
Géry Debongnie	64bad25762	[REL] v2.0.0-beta-22 # v2.0.0-beta-22 - fix: t-call: nested t-call with magic variable 0 - fix: prevent crash in case with t-foreach, t-out and components	2022-09-29 09:17:06 +02:00
Géry Debongnie	7ab34c5ca5	[FIX] prevent crash in case with t-foreach and t-out with components The t-out directive is compiled internally into a LazyValue, which represents a value that may or may not be created sometimes in the future. It can also be reused more than once, and this is where there may be an issue: if a component is contained in the lazyvalue, it needs a unique key (coming from the t-foreach) to be properly indexed in the parent children map. However, the LazyValue does not keep the key information, so it is not able to provide it to its content. The fix is then quite clear: the LazyValue class should store the key information, and provides it to its content. This allows the LazyValue to be used multiple times, in any place in a template. closes #1270	2022-09-29 08:28:38 +02:00
Géry Debongnie	669fd622ec	[FIX] t-call: nested t-call with magic variable 0 Before this commit, the template compiler would guess the next block id that will be generated when compiling the body of a tcall. This is correct IF there are not nested t-call, but otherwise wrong, because the next block id could be mixed up: the first t-call would save the next block id (let's say n), then the inner t-call would also save the same block id (so, n), will then generate its own block (n+1), then the outer t-call would use the block n index instead of n+1 The best fix, in my opinion, is to make sure we get the next block var name, so we do not have to guess. To do that, each compile block type function needs to properly return the information. closes #1267	2022-09-28 09:31:41 +02:00
Géry Debongnie	ab72cdddde	[REL] v2.0.0-beta-21 # v2.0.0-beta-21 - fix: prevent side effects at template compilation - fix: props validation: does not crash with t-call-context - fix: make t-portal work in all cases - fix: make props validation work through slots	2022-09-26 15:44:11 +02:00
Géry Debongnie	17fb33475c	[FIX] props validation: make it work through slots A recent commit fixes the props validation code to make it work regardless of the rendering context (important with the recent t-call-context directive). Unfortunately, it then breaks props validation through slots, because it assumed that the parent node in the virtual node was the parent of the component, but it is not necessarily true. To fix this, we can use a simple property of the template functions: they are bound to the current instance of the component, so we can simply use "this"	2022-09-26 15:17:58 +02:00
Géry Debongnie	ab29b896eb	[FIX] portal: make it work in all cases Before this commit, the portal wouldn't work when its target is created after the portal content, since it wouldn't be able to mount the dom at the correct location. With this commit, we work around the issue by mounting the portal content at the portal location, then when the Portal component is mounted, moving it to its correct location. The big downside with that approach is that the portal content is (sometimes) rendered and mounted at a location, THEN mounted in another location. I think that it is most of the time not an issue, but one could argue that it is inconsistent: some specific code could work at one point, then fail in a different very similar situation (for example, iframes don't support very well being moved around). On the flip side, having the portal work as expected is very useful, and may be worth the tradeoff. closes #1250	2022-09-26 12:01:12 +02:00
Géry Debongnie	d5ed25cd19	[FIX] props validation: does not crash with t-call-context The code for props validation assumed that the rendering context was a component. This was actually true when it was written, but is no longer true since t-call-context was introduced. Because of that, it would crash when trying to access the internals of the component, such as the static components object. The fix is simple: instead of passing the context to the props validation code, which can now be anything, we pass the component node, which is guaranteed to give a reference to the component (and also to the app). This also make the code slightly simpler. closes #1261	2022-09-24 08:34:22 +02:00
Géry Debongnie	c4f0f17b9b	[FIX] blockdom: prevent side effects at block compilation When creating the template node for a block, we create htmlelements and set their (static) attributes. But this can have side effects. For example, setting the src attribute for an img element will trigger a request to fetch the image. We avoid that issue by simply setting the html element template node inside a <template/> element. Note that I don't really see how to test this fix in jest: we don't have a real browser, and no real way to check for this side effect. closes #1257	2022-09-21 13:59:13 +02:00
Florent Dardenne - dafl@odoo	d27455e9f2	[IMP] doc: explicit `useEffect` first parameter The `useEffect` has two parameters: * The `effect` function * The `computeDependencies` function The `effect` function always take as parameters the result of the `computeDependencies` function. Expliciting this allows to better understand the `useEffect` behaviour and the following example in the doc: ``` useEffect( (el) => el && el.focus(), () => [ref.el] ); ```	2022-09-09 20:24:56 +02:00
Géry Debongnie	6ef38676c4	[DOC] doc: fix broken link and update roadmap	2022-09-09 09:45:05 +02:00
Géry Debongnie	b51756f356	[REL] v2.0.0-beta-20 # v2.0.0-beta-20 - app: properly rethrow unhandled errors	2022-09-09 09:26:12 +02:00
Samuel Degueldre	cfdf7caa50	[IMP] app: rethrow errors that were not handled This commit makes it so that when an error occurs in an owl app and none of the registered error handlers are able to handle it, we rethrow the error instead of just logging it to the console and swallowing it. This allows users of owl to handle errors that happen in owl applications by using event listeners for error and unhandledrejection events on the window.	2022-09-09 09:23:32 +02:00
Florent Dardenne - dafl@odoo	a5a6a592c1	[FIX] tutorial_todoapp: fix the final code mount issue In app.js, `mount(Root, document.body, { dev: true, env });` crash because `body` is not available yet. Therefore, moving the script into the body fix the issue.	2022-09-08 13:30:38 +02:00
Géry Debongnie	d0d7482b0f	[REL] v2.0.0-beta-19 # v2.0.0-beta-19 - fix: events: correctly call handlers in iframes	2022-09-06 12:13:25 +02:00
Samuel Degueldre	8fe4c0c76e	[FIX] events: correctly call handlers in iframes Previously, event handlers would not work when an app was mounted in an iframe, this is caused by a guard in the event handler that checks that the target element is still in the document, but it doesn't check against the correct document in the case of an iframe. This commit changes the check to check against the target's ownerDocument.	2022-09-06 12:06:59 +02:00
Géry Debongnie	c1afaeb92a	[REL] v2.0.0-beta-18 # v2.0.0-beta-18 - fix: allow multiple occurrences of same slot in different locations	2022-09-02 14:57:18 +02:00
Géry Debongnie	3883cec079	[FIX] slots: prevent crash when using same slot in different locations Before this commit, a crash could occur when a component with no props is defined in a slot, and that slot is conditionally displayed in multiple locations. The reason for that is that the key provided to the callSlot function was identical, so from the perspective of the component function, it was not possible to make the difference between a component located in either places. With this commit, we make sure that a unique key is used when a slot is reused in a template (or if it is dynamic, because in that case, we have no idea at compile time if it will be unique or not) closes #1246	2022-09-02 12:12:00 +02:00