[REL] v2.2.4

# v2.2.4

 - [FIX] compiler: fix swapped key/value using t-foreach on Map
 - [FIX] devtools: fix crash while highlighting env
 - [FIX] *: move OwlError to common
 - [FIX] playground: todo app clear complete tasks
 - [IMP] compiler: improve error message when failing to compile template

doc/reference/templates.md

@@ -376,15 +376,16 @@ An important difference should be made with the usual `QWeb` behaviour: Owl
 requires the presence of a `t-key` directive, to be able to properly reconcile
 renderings.
 
-`t-foreach` can iterate on an array (the current item will be the current value)
-or an object (the current item will be the current key).
+`t-foreach` can iterate on any iterable, and also has special support for objects
+and maps, it will expose the key of the current iteration as the contents of the
+`t-as`, and the corresponding value with the same name and the suffix `_value`.
 
-In addition to the name passed via t-as, `t-foreach` provides a few other
-variables for various data points (note: `$as` will be replaced with the name
-passed to `t-as`):
+In addition to the name passed via t-as, `t-foreach` provides a few other useful
+variables (note: `$as` will be replaced with the name passed to `t-as`):
 
-- `$as_value`: the current iteration value, identical to `$as` for lists and
-  integers, but for objects, it provides the value (where `$as` provides the key)
+- `$as_value`: the current iteration value, identical to `$as` for arrays and
+  other iterables, but for objects and maps, it provides the value (where `$as`
+  provides the key)
 - `$as_index`: the current iteration index (the first item of the iteration has index 0)
 - `$as_first`: whether the current item is the first of the iteration
   (equivalent to `$as_index == 0`)

docs/owl.js

@@ -82,65 +82,6 @@ function toggler(key, child) {
 
 // Custom error class that wraps error that happen in the owl lifecycle
 class OwlError extends Error {
-}
-// Maps fibers to thrown errors
-const fibersInError = new WeakMap();
-const nodeErrorHandlers = new WeakMap();
-function _handleError(node, error) {
-    if (!node) {
-        return false;
-    }
-    const fiber = node.fiber;
-    if (fiber) {
-        fibersInError.set(fiber, error);
-    }
-    const errorHandlers = nodeErrorHandlers.get(node);
-    if (errorHandlers) {
-        let handled = false;
-        // execute in the opposite order
-        for (let i = errorHandlers.length - 1; i >= 0; i--) {
-            try {
-                errorHandlers[i](error);
-                handled = true;
-                break;
-            }
-            catch (e) {
-                error = e;
-            }
-        }
-        if (handled) {
-            return true;
-        }
-    }
-    return _handleError(node.parent, error);
-}
-function handleError(params) {
-    let { error } = params;
-    // Wrap error if it wasn't wrapped by wrapError (ie when not in dev mode)
-    if (!(error instanceof OwlError)) {
-        error = Object.assign(new OwlError(`An error occured in the owl lifecycle (see this Error's "cause" property)`), { cause: error });
-    }
-    const node = "node" in params ? params.node : params.fiber.node;
-    const fiber = "fiber" in params ? params.fiber : node.fiber;
-    // resets the fibers on components if possible. This is important so that
-    // new renderings can be properly included in the initial one, if any.
-    let current = fiber;
-    do {
-        current.node.fiber = current;
-        current = current.parent;
-    } while (current);
-    fibersInError.set(fiber.root, error);
-    const handled = _handleError(node, error);
-    if (!handled) {
-        console.warn(`[Owl] Unhandled error. Destroying the root component`);
-        try {
-            node.app.destroy();
-        }
-        catch (e) {
-            console.error(e);
-        }
-        throw error;
-    }
 }
 
 const { setAttribute: elemSetAttribute, removeAttribute } = Element.prototype;
@@ -311,20 +252,13 @@ function updateClass(val, oldVal) {
  * @returns a batched version of the original callback
  */
 function batched(callback) {
-    let called = false;
-    return async () => {
-        // This await blocks all calls to the callback here, then releases them sequentially
-        // in the next microtick. This line decides the granularity of the batch.
-        await Promise.resolve();
-        if (!called) {
-            called = true;
-            // wait for all calls in this microtick to fall through before resetting "called"
-            // so that only the first call to the batched function calls the original callback.
-            // Schedule this before calling the callback so that calls to the batched function
-            // within the callback will proceed only after resetting called to false, and have
-            // a chance to execute the callback again
-            Promise.resolve().then(() => (called = false));
-            callback();
+    let scheduled = false;
+    return async (...args) => {
+        if (!scheduled) {
+            scheduled = true;
+            await Promise.resolve();
+            scheduled = false;
+            callback(...args);
         }
     };
 }
@@ -1608,6 +1542,68 @@ function remove(vnode, withBeforeRemove = false) {
     vnode.remove();
 }
 
+// Maps fibers to thrown errors
+const fibersInError = new WeakMap();
+const nodeErrorHandlers = new WeakMap();
+function _handleError(node, error) {
+    if (!node) {
+        return false;
+    }
+    const fiber = node.fiber;
+    if (fiber) {
+        fibersInError.set(fiber, error);
+    }
+    const errorHandlers = nodeErrorHandlers.get(node);
+    if (errorHandlers) {
+        let handled = false;
+        // execute in the opposite order
+        for (let i = errorHandlers.length - 1; i >= 0; i--) {
+            try {
+                errorHandlers[i](error);
+                handled = true;
+                break;
+            }
+            catch (e) {
+                error = e;
+            }
+        }
+        if (handled) {
+            return true;
+        }
+    }
+    return _handleError(node.parent, error);
+}
+function handleError(params) {
+    let { error } = params;
+    // Wrap error if it wasn't wrapped by wrapError (ie when not in dev mode)
+    if (!(error instanceof OwlError)) {
+        error = Object.assign(new OwlError(`An error occured in the owl lifecycle (see this Error's "cause" property)`), { cause: error });
+    }
+    const node = "node" in params ? params.node : params.fiber.node;
+    const fiber = "fiber" in params ? params.fiber : node.fiber;
+    if (fiber) {
+        // resets the fibers on components if possible. This is important so that
+        // new renderings can be properly included in the initial one, if any.
+        let current = fiber;
+        do {
+            current.node.fiber = current;
+            current = current.parent;
+        } while (current);
+        fibersInError.set(fiber.root, error);
+    }
+    const handled = _handleError(node, error);
+    if (!handled) {
+        console.warn(`[Owl] Unhandled error. Destroying the root component`);
+        try {
+            node.app.destroy();
+        }
+        catch (e) {
+            console.error(e);
+        }
+        throw error;
+    }
+}
+
 function makeChildFiber(node, parent) {
     let current = node.fiber;
     if (current) {
@@ -1657,8 +1653,7 @@ function cancelFibers(fibers) {
         let node = fiber.node;
         fiber.render = throwOnRender;
         if (node.status === 0 /* NEW */) {
-            node.destroy();
-            delete node.parent.children[node.parentKey];
+            node.cancel();
         }
         node.fiber = null;
         if (fiber.bdom) {
@@ -2385,6 +2380,9 @@ class ComponentNode {
         }
     }
     async render(deep) {
+        if (this.status >= 2 /* CANCELLED */) {
+            return;
+        }
         let current = this.fiber;
         if (current && (current.root.locked || current.bdom === true)) {
             await Promise.resolve();
@@ -2410,7 +2408,7 @@ class ComponentNode {
         this.fiber = fiber;
         this.app.scheduler.addFiber(fiber);
         await Promise.resolve();
-        if (this.status === 2 /* DESTROYED */) {
+        if (this.status >= 2 /* CANCELLED */) {
             return;
         }
         // We only want to actually render the component if the following two
@@ -2428,6 +2426,18 @@ class ComponentNode {
             fiber.render();
         }
     }
+    cancel() {
+        this._cancel();
+        delete this.parent.children[this.parentKey];
+        this.app.scheduler.scheduleDestroy(this);
+    }
+    _cancel() {
+        this.status = 2 /* CANCELLED */;
+        const children = this.children;
+        for (let childKey in children) {
+            children[childKey]._cancel();
+        }
+    }
     destroy() {
         let shouldRemove = this.status === 1 /* MOUNTED */;
         this._destroy();
@@ -2455,7 +2465,7 @@ class ComponentNode {
                 this.app.handleError({ error: e, node: this });
             }
         }
-        this.status = 2 /* DESTROYED */;
+        this.status = 3 /* DESTROYED */;
     }
     async updateAndRender(props, parentFiber) {
         this.nextProps = props;
@@ -2988,12 +2998,22 @@ function prepareList(collection) {
         keys = collection;
         values = collection;
     }
-    else if (collection) {
-        values = Object.keys(collection);
-        keys = Object.values(collection);
+    else if (collection instanceof Map) {
+        keys = [...collection.keys()];
+        values = [...collection.values()];
+    }
+    else if (collection && typeof collection === "object") {
+        if (Symbol.iterator in collection) {
+            keys = [...collection];
+            values = keys;
+        }
+        else {
+            values = Object.values(collection);
+            keys = Object.keys(collection);
+        }
     }
     else {
-        throw new OwlError("Invalid loop expression");
+        throw new OwlError(`Invalid loop expression: "${collection}" is not iterable`);
     }
     const n = values.length;
     return [keys, values, n, new Array(n)];
@@ -4327,18 +4347,18 @@ class CodeGenerator {
         }
         this.addLine(`for (let ${loopVar} = 0; ${loopVar} < ${l}; ${loopVar}++) {`);
         this.target.indentLevel++;
-        this.addLine(`ctx[\`${ast.elem}\`] = ${vals}[${loopVar}];`);
+        this.addLine(`ctx[\`${ast.elem}\`] = ${keys}[${loopVar}];`);
         if (!ast.hasNoFirst) {
             this.addLine(`ctx[\`${ast.elem}_first\`] = ${loopVar} === 0;`);
         }
         if (!ast.hasNoLast) {
-            this.addLine(`ctx[\`${ast.elem}_last\`] = ${loopVar} === ${vals}.length - 1;`);
+            this.addLine(`ctx[\`${ast.elem}_last\`] = ${loopVar} === ${keys}.length - 1;`);
         }
         if (!ast.hasNoIndex) {
             this.addLine(`ctx[\`${ast.elem}_index\`] = ${loopVar};`);
         }
         if (!ast.hasNoValue) {
-            this.addLine(`ctx[\`${ast.elem}_value\`] = ${keys}[${loopVar}];`);
+            this.addLine(`ctx[\`${ast.elem}_value\`] = ${vals}[${loopVar}];`);
         }
         this.define(`key${this.target.loopLevel}`, ast.key ? compileExpr(ast.key) : loopVar);
         if (this.dev) {
@@ -4820,10 +4840,10 @@ function parseNode(node, ctx) {
         parseTCall(node, ctx) ||
         parseTCallBlock(node) ||
         parseTEscNode(node, ctx) ||
+        parseTOutNode(node, ctx) ||
         parseTKey(node, ctx) ||
         parseTTranslation(node, ctx) ||
         parseTSlot(node, ctx) ||
-        parseTOutNode(node, ctx) ||
         parseComponent(node, ctx) ||
         parseDOMNode(node, ctx) ||
         parseTSetNode(node, ctx) ||
@@ -4936,10 +4956,8 @@ function parseDOMNode(node, ctx) {
             const typeAttr = node.getAttribute("type");
             const isInput = tagName === "input";
             const isSelect = tagName === "select";
-            const isTextarea = tagName === "textarea";
             const isCheckboxInput = isInput && typeAttr === "checkbox";
             const isRadioInput = isInput && typeAttr === "radio";
-            const isOtherInput = isInput && !isCheckboxInput && !isRadioInput;
             const hasLazyMod = attr.includes(".lazy");
             const hasNumberMod = attr.includes(".number");
             const hasTrimMod = attr.includes(".trim");
@@ -4951,8 +4969,8 @@ function parseDOMNode(node, ctx) {
                 specialInitTargetAttr: isRadioInput ? "checked" : null,
                 eventType,
                 hasDynamicChildren: false,
-                shouldTrim: hasTrimMod && (isOtherInput || isTextarea),
-                shouldNumberize: hasNumberMod && (isOtherInput || isTextarea),
+                shouldTrim: hasTrimMod,
+                shouldNumberize: hasNumberMod,
             };
             if (isSelect) {
                 // don't pollute the original ctx
@@ -5015,9 +5033,6 @@ function parseTEscNode(node, ctx) {
             content: [tesc],
         };
     }
-    if (ast.type === 11 /* TComponent */) {
-        throw new OwlError("t-esc is not supported on Component nodes");
-    }
     return tesc;
 }
 // -----------------------------------------------------------------------------
@@ -5459,19 +5474,21 @@ function normalizeTIf(el) {
  *
  * @param el the element containing the tree that should be normalized
  */
-function normalizeTEsc(el) {
-    const elements = [...el.querySelectorAll("[t-esc]")].filter((el) => el.tagName[0] === el.tagName[0].toUpperCase() || el.hasAttribute("t-component"));
-    for (const el of elements) {
-        if (el.childNodes.length) {
-            throw new OwlError("Cannot have t-esc on a component that already has content");
+function normalizeTEscTOut(el) {
+    for (const d of ["t-esc", "t-out"]) {
+        const elements = [...el.querySelectorAll(`[${d}]`)].filter((el) => el.tagName[0] === el.tagName[0].toUpperCase() || el.hasAttribute("t-component"));
+        for (const el of elements) {
+            if (el.childNodes.length) {
+                throw new OwlError(`Cannot have ${d} on a component that already has content`);
+            }
+            const value = el.getAttribute(d);
+            el.removeAttribute(d);
+            const t = el.ownerDocument.createElement("t");
+            if (value != null) {
+                t.setAttribute(d, value);
+            }
+            el.appendChild(t);
         }
-        const value = el.getAttribute("t-esc");
-        el.removeAttribute("t-esc");
-        const t = el.ownerDocument.createElement("t");
-        if (value != null) {
-            t.setAttribute("t-esc", value);
-        }
-        el.appendChild(t);
     }
 }
 /**
@@ -5482,7 +5499,7 @@ function normalizeTEsc(el) {
  */
 function normalizeXML(el) {
     normalizeTIf(el);
-    normalizeTEsc(el);
+    normalizeTEscTOut(el);
 }
 /**
  * Parses an XML string into an XML document, throwing errors on parser errors
@@ -5531,11 +5548,20 @@ function compile(template, options = {}) {
     const codeGenerator = new CodeGenerator(ast, { ...options, hasSafeContext });
     const code = codeGenerator.generateCode();
     // template function
-    return new Function("app, bdom, helpers", code);
+    try {
+        return new Function("app, bdom, helpers", code);
+    }
+    catch (originalError) {
+        const { name } = options;
+        const nameStr = name ? `template "${name}"` : "anonymous template";
+        const err = new OwlError(`Failed to compile ${nameStr}: ${originalError.message}\n\ngenerated code:\nfunction(app, bdom, helpers) {\n${code}\n}`);
+        err.cause = originalError;
+        throw err;
+    }
 }
 
 // do not modify manually. This file is generated by the release script.
-const version = "2.1.3";
+const version = "2.2.4";
 
 // -----------------------------------------------------------------------------
 //  Scheduler
@@ -5545,11 +5571,18 @@ class Scheduler {
         this.tasks = new Set();
         this.frame = 0;
         this.delayedRenders = [];
+        this.cancelledNodes = new Set();
         this.requestAnimationFrame = Scheduler.requestAnimationFrame;
     }
     addFiber(fiber) {
         this.tasks.add(fiber.root);
     }
+    scheduleDestroy(node) {
+        this.cancelledNodes.add(node);
+        if (this.frame === 0) {
+            this.frame = this.requestAnimationFrame(() => this.processTasks());
+        }
+    }
     /**
      * Process all current tasks. This only applies to the fibers that are ready.
      * Other tasks are left unchanged.
@@ -5559,21 +5592,28 @@ class Scheduler {
             let renders = this.delayedRenders;
             this.delayedRenders = [];
             for (let f of renders) {
-                if (f.root && f.node.status !== 2 /* DESTROYED */ && f.node.fiber === f) {
+                if (f.root && f.node.status !== 3 /* DESTROYED */ && f.node.fiber === f) {
                     f.render();
                 }
             }
         }
         if (this.frame === 0) {
-            this.frame = this.requestAnimationFrame(() => {
-                this.frame = 0;
-                this.tasks.forEach((fiber) => this.processFiber(fiber));
-                for (let task of this.tasks) {
-                    if (task.node.status === 2 /* DESTROYED */) {
-                        this.tasks.delete(task);
-                    }
-                }
-            });
+            this.frame = this.requestAnimationFrame(() => this.processTasks());
+        }
+    }
+    processTasks() {
+        this.frame = 0;
+        for (let node of this.cancelledNodes) {
+            node._destroy();
+        }
+        this.cancelledNodes.clear();
+        for (let task of this.tasks) {
+            this.processFiber(task);
+        }
+        for (let task of this.tasks) {
+            if (task.node.status === 3 /* DESTROYED */) {
+                this.tasks.delete(task);
+            }
         }
     }
     processFiber(fiber) {
@@ -5586,7 +5626,7 @@ class Scheduler {
             this.tasks.delete(fiber);
             return;
         }
-        if (fiber.node.status === 2 /* DESTROYED */) {
+        if (fiber.node.status === 3 /* DESTROYED */) {
             this.tasks.delete(fiber);
             return;
         }
@@ -5678,8 +5718,8 @@ class App extends TemplateSet {
     }
     destroy() {
         if (this.root) {
-            this.scheduler.flush();
             this.root.destroy();
+            this.scheduler.processTasks();
         }
         window.__OWL_DEVTOOLS__.apps.delete(this);
     }
@@ -5810,9 +5850,11 @@ function status(component) {
     switch (component.__owl__.status) {
         case 0 /* NEW */:
             return "new";
+        case 2 /* CANCELLED */:
+            return "cancelled";
         case 1 /* MOUNTED */:
             return "mounted";
-        case 2 /* DESTROYED */:
+        case 3 /* DESTROYED */:
             return "destroyed";
     }
 }
@@ -5952,6 +5994,6 @@ TemplateSet.prototype._compileTemplate = function _compileTemplate(name, templat
 export { App, Component, EventBus, OwlError, __info__, blockDom, loadFile, markRaw, markup, mount, onError, onMounted, onPatched, onRendered, onWillDestroy, onWillPatch, onWillRender, onWillStart, onWillUnmount, onWillUpdateProps, reactive, status, toRaw, useChildSubEnv, useComponent, useEffect, useEnv, useExternalListener, useRef, useState, useSubEnv, validate, validateType, whenReady, xml };
 
 
-__info__.date = '2023-06-28T09:17:13.630Z';
-__info__.hash = '432ff44';
+__info__.date = '2023-08-02T06:20:03.634Z';
+__info__.hash = '8f9ad98';
 __info__.url = 'https://github.com/odoo/owl';

docs/playground/samples/todo_app/todo_app.js

@@ -43,10 +43,6 @@ class TaskList {
         }
     }
 
-    toggleTask(task) {
-        task.isCompleted = !task.isCompleted;
-    }
-
     toggleTask(id) {
         const task = this.tasks.find(t => t.id === id);
         task.isCompleted = !task.isCompleted;
@@ -61,7 +57,7 @@ class TaskList {
     clearCompleted() {
         const tasks = this.tasks.filter(t => t.isCompleted);
         for (let task of tasks) {
-            this.deleteTask(task);
+            this.deleteTask(task.id);
         }
     }
     

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@odoo/owl",
-  "version": "2.1.4",
+  "version": "2.2.4",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@odoo/owl",
-  "version": "2.1.4",
+  "version": "2.2.4",
   "description": "Odoo Web Library (OWL)",
   "main": "dist/owl.cjs.js",
   "module": "dist/owl.es.js",

src/common/owl_error.ts

@@ -0,0 +1,4 @@
+// Custom error class that wraps error that happen in the owl lifecycle
+export class OwlError extends Error {
+  cause?: any;
+}

src/compiler/code_generator.ts

@@ -29,7 +29,7 @@ import {
   Attrs,
   EventHandlers,
 } from "./parser";
-import { OwlError } from "../runtime/error_handling";
+import { OwlError } from "../common/owl_error";
 
 type BlockType = "block" | "text" | "multi" | "list" | "html" | "comment";
 const whitespaceRE = /\s+/g;
@@ -894,18 +894,18 @@ export class CodeGenerator {
     }
     this.addLine(`for (let ${loopVar} = 0; ${loopVar} < ${l}; ${loopVar}++) {`);
     this.target.indentLevel++;
-    this.addLine(`ctx[\`${ast.elem}\`] = ${vals}[${loopVar}];`);
+    this.addLine(`ctx[\`${ast.elem}\`] = ${keys}[${loopVar}];`);
     if (!ast.hasNoFirst) {
       this.addLine(`ctx[\`${ast.elem}_first\`] = ${loopVar} === 0;`);
     }
     if (!ast.hasNoLast) {
-      this.addLine(`ctx[\`${ast.elem}_last\`] = ${loopVar} === ${vals}.length - 1;`);
+      this.addLine(`ctx[\`${ast.elem}_last\`] = ${loopVar} === ${keys}.length - 1;`);
     }
     if (!ast.hasNoIndex) {
       this.addLine(`ctx[\`${ast.elem}_index\`] = ${loopVar};`);
     }
     if (!ast.hasNoValue) {
-      this.addLine(`ctx[\`${ast.elem}_value\`] = ${keys}[${loopVar}];`);
+      this.addLine(`ctx[\`${ast.elem}_value\`] = ${vals}[${loopVar}];`);
     }
     this.define(`key${this.target.loopLevel}`, ast.key ? compileExpr(ast.key) : loopVar);
     if (this.dev) {

src/compiler/index.ts

@@ -2,6 +2,7 @@ import type { TemplateSet } from "../runtime/template_set";
 import type { BDom } from "../runtime/blockdom";
 import { CodeGenerator, Config } from "./code_generator";
 import { parse } from "./parser";
+import { OwlError } from "../common/owl_error";
 
 export type Template = (context: any, vnode: any, key?: string) => BDom;
 
@@ -27,5 +28,15 @@ export function compile(
   const codeGenerator = new CodeGenerator(ast, { ...options, hasSafeContext });
   const code = codeGenerator.generateCode();
   // template function
-  return new Function("app, bdom, helpers", code) as TemplateFunction;
+  try {
+    return new Function("app, bdom, helpers", code) as TemplateFunction;
+  } catch (originalError: any) {
+    const { name } = options;
+    const nameStr = name ? `template "${name}"` : "anonymous template";
+    const err = new OwlError(
+      `Failed to compile ${nameStr}: ${originalError.message}\n\ngenerated code:\nfunction(app, bdom, helpers) {\n${code}\n}`
+    );
+    err.cause = originalError;
+    throw err;
+  }
 }

src/compiler/inline_expressions.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "../runtime/error_handling";
+import { OwlError } from "../common/owl_error";
 
 /**
  * Owl QWeb Expression Parser

src/compiler/parser.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "../runtime/error_handling";
+import { OwlError } from "../common/owl_error";
 
 // -----------------------------------------------------------------------------
 // AST Type definition
@@ -235,10 +235,10 @@ function parseNode(node: Node, ctx: ParsingContext): AST | null {
     parseTCall(node, ctx) ||
     parseTCallBlock(node, ctx) ||
     parseTEscNode(node, ctx) ||
+    parseTOutNode(node, ctx) ||
     parseTKey(node, ctx) ||
     parseTTranslation(node, ctx) ||
     parseTSlot(node, ctx) ||
-    parseTOutNode(node, ctx) ||
     parseComponent(node, ctx) ||
     parseDOMNode(node, ctx) ||
     parseTSetNode(node, ctx) ||
@@ -444,9 +444,6 @@ function parseTEscNode(node: Element, ctx: ParsingContext): AST | null {
       content: [tesc],
     };
   }
-  if (ast.type === ASTType.TComponent) {
-    throw new OwlError("t-esc is not supported on Component nodes");
-  }
   return tesc;
 }
 
@@ -941,21 +938,23 @@ function normalizeTIf(el: Element) {
  *
  * @param el the element containing the tree that should be normalized
  */
-function normalizeTEsc(el: Element) {
-  const elements = [...el.querySelectorAll("[t-esc]")].filter(
-    (el) => el.tagName[0] === el.tagName[0].toUpperCase() || el.hasAttribute("t-component")
-  );
-  for (const el of elements) {
-    if (el.childNodes.length) {
-      throw new OwlError("Cannot have t-esc on a component that already has content");
+function normalizeTEscTOut(el: Element) {
+  for (const d of ["t-esc", "t-out"]) {
+    const elements = [...el.querySelectorAll(`[${d}]`)].filter(
+      (el) => el.tagName[0] === el.tagName[0].toUpperCase() || el.hasAttribute("t-component")
+    );
+    for (const el of elements) {
+      if (el.childNodes.length) {
+        throw new OwlError(`Cannot have ${d} on a component that already has content`);
+      }
+      const value = el.getAttribute(d);
+      el.removeAttribute(d);
+      const t = el.ownerDocument.createElement("t");
+      if (value != null) {
+        t.setAttribute(d, value);
+      }
+      el.appendChild(t);
     }
-    const value = el.getAttribute("t-esc");
-    el.removeAttribute("t-esc");
-    const t = el.ownerDocument.createElement("t");
-    if (value != null) {
-      t.setAttribute("t-esc", value);
-    }
-    el.appendChild(t);
   }
 }
 
@@ -967,7 +966,7 @@ function normalizeTEsc(el: Element) {
  */
 function normalizeXML(el: Element) {
   normalizeTIf(el);
-  normalizeTEsc(el);
+  normalizeTEscTOut(el);
 }
 
 /**

src/runtime/app.ts

@@ -1,7 +1,8 @@
 import { version } from "../version";
 import { Component, ComponentConstructor, Props } from "./component";
 import { ComponentNode } from "./component_node";
-import { nodeErrorHandlers, OwlError, handleError } from "./error_handling";
+import { nodeErrorHandlers, handleError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 import { Fiber, RootFiber, MountOptions } from "./fibers";
 import { Scheduler } from "./scheduler";
 import { validateProps } from "./template_helpers";
@@ -136,8 +137,8 @@ export class App<
 
   destroy() {
     if (this.root) {
-      this.scheduler.flush();
       this.root.destroy();
+      this.scheduler.processTasks();
     }
     window.__OWL_DEVTOOLS__.apps.delete(this);
   }

src/runtime/blockdom/block_compiler.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "../error_handling";
+import { OwlError } from "../../common/owl_error";
 import { attrsSetter, attrsUpdater, createAttrUpdater, setClass, updateClass } from "./attributes";
 import { config } from "./config";
 import { createEventHandler } from "./events";

src/runtime/component_node.ts

@@ -1,7 +1,8 @@
 import type { App, Env } from "./app";
 import { BDom, VNode } from "./blockdom";
 import { Component, ComponentConstructor, Props } from "./component";
-import { fibersInError, OwlError } from "./error_handling";
+import { fibersInError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 import { Fiber, makeChildFiber, makeRootFiber, MountFiber, MountOptions } from "./fibers";
 import { clearReactivesForCallback, getSubscriptions, reactive, targets } from "./reactivity";
 import { STATUS } from "./status";

src/runtime/error_handling.ts

@@ -1,11 +1,7 @@
+import { OwlError } from "../common/owl_error";
 import type { ComponentNode } from "./component_node";
 import type { Fiber } from "./fibers";
 
-// Custom error class that wraps error that happen in the owl lifecycle
-export class OwlError extends Error {
-  cause?: any;
-}
-
 // Maps fibers to thrown errors
 export const fibersInError: WeakMap<Fiber, any> = new WeakMap();
 export const nodeErrorHandlers: WeakMap<ComponentNode, ((error: any) => void)[]> = new WeakMap();

src/runtime/event_handling.ts

@@ -1,6 +1,6 @@
 import { filterOutModifiersFromData } from "./blockdom/config";
 import { STATUS } from "./status";
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 
 export const mainEventHandler = (data: any, ev: Event, currentTarget?: EventTarget | null) => {
   const { data: _data, modifiers } = filterOutModifiersFromData(data);

src/runtime/fibers.ts

@@ -1,6 +1,7 @@
 import { BDom, mount } from "./blockdom";
 import type { ComponentNode } from "./component_node";
-import { fibersInError, OwlError } from "./error_handling";
+import { fibersInError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 import { STATUS } from "./status";
 
 export function makeChildFiber(node: ComponentNode, parent: Fiber): Fiber {

src/runtime/index.ts

@@ -55,7 +55,7 @@ export {
   onError,
 } from "./lifecycle_hooks";
 export { validate, validateType } from "./validation";
-export { OwlError } from "./error_handling";
+export { OwlError } from "../common/owl_error";
 
 export const __info__ = {
   version: App.version,

src/runtime/lifecycle_hooks.ts

@@ -1,5 +1,6 @@
 import { getCurrent } from "./component_node";
-import { nodeErrorHandlers, OwlError } from "./error_handling";
+import { nodeErrorHandlers } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 
 const TIMEOUT = Symbol("timeout");
 function wrapError(fn: (...args: any[]) => any, hookName: string) {

src/runtime/portal.ts

@@ -1,7 +1,7 @@
 import { onMounted, onWillUnmount } from "./lifecycle_hooks";
 import { BDom, text, VNode } from "./blockdom";
 import { Component } from "./component";
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 
 const VText: any = text("").constructor;
 

src/runtime/reactivity.ts

@@ -1,5 +1,5 @@
 import type { Callback } from "./utils";
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 
 // Special key to subscribe to, to be notified of key creation/deletion
 const KEYCHANGES = Symbol("Key changes");

src/runtime/template_helpers.ts

@@ -4,7 +4,7 @@ import { html } from "./blockdom/index";
 import { isOptional, validateSchema } from "./validation";
 import type { ComponentConstructor } from "./component";
 import { markRaw } from "./reactivity";
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 import type { ComponentNode } from "./component_node";
 
 const ObjectCreate = Object.create;
@@ -60,18 +60,26 @@ function withKey(elem: any, k: string) {
   return elem;
 }
 
-function prepareList(collection: any): [any[], any[], number, any[]] {
-  let keys: any[];
-  let values: any[];
+function prepareList(collection: unknown): [unknown[], unknown[], number, undefined[]] {
+  let keys: unknown[];
+  let values: unknown[];
 
   if (Array.isArray(collection)) {
     keys = collection;
     values = collection;
-  } else if (collection) {
-    values = Object.keys(collection);
-    keys = Object.values(collection);
+  } else if (collection instanceof Map) {
+    keys = [...collection.keys()];
+    values = [...collection.values()];
+  } else if (collection && typeof collection === "object") {
+    if (Symbol.iterator in collection) {
+      keys = [...(<Iterable<unknown>>collection)];
+      values = keys;
+    } else {
+      values = Object.values(collection);
+      keys = Object.keys(collection);
+    }
   } else {
-    throw new OwlError("Invalid loop expression");
+    throw new OwlError(`Invalid loop expression: "${collection}" is not iterable`);
   }
   const n = values.length;
   return [keys, values, n, new Array(n)];

src/runtime/template_set.ts

@@ -3,7 +3,7 @@ import { comment, createBlock, html, list, multi, text, toggler } from "./blockd
 import { getCurrent } from "./component_node";
 import { Portal, portalTemplate } from "./portal";
 import { helpers } from "./template_helpers";
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 
 const bdom = { text, createBlock, list, multi, html, toggler, comment };
 

src/runtime/utils.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 export type Callback = () => void;
 
 /**

src/runtime/validation.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "./error_handling";
+import { OwlError } from "../common/owl_error";
 import { toRaw } from "./reactivity";
 
 type BaseType =

src/version.ts

@@ -1,2 +1,2 @@
 // do not modify manually. This file is generated by the release script.
-export const version = "2.1.4";
+export const version = "2.2.4";

tests/__snapshots__/reactivity.test.ts.snap

@@ -353,7 +353,7 @@ exports[`Reactivity: useState useless atoms should be deleted 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Object.keys(ctx['state']));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`id\`] = v_block2[i1];
+      ctx[\`id\`] = k_block2[i1];
       const key1 = ctx['id'];
       c_block2[i1] = withKey(comp1({id: ctx['id']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }

tests/app/__snapshots__/app.test.ts.snap

@@ -15,6 +15,34 @@ exports[`app App supports env with getters/setters 1`] = `
 }"
 `;
 
+exports[`app app: clear scheduler tasks and destroy cancelled nodes immediately on destroy 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`B\`, true, false, false, []);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let b2,b3;
+    b2 = text(\`A\`);
+    if (ctx['state'].value) {
+      b3 = comp1({}, key + \`__1\`, node, this, null);
+    }
+    return multi([b2, b3]);
+  }
+}"
+`;
+
+exports[`app app: clear scheduler tasks and destroy cancelled nodes immediately on destroy 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  return function template(ctx, node, key = \\"\\") {
+    return text(\`B\`);
+  }
+}"
+`;
+
 exports[`app can configure an app with props 1`] = `
 "function anonymous(app, bdom, helpers
 ) {

tests/app/app.test.ts

@@ -1,6 +1,14 @@
-import { App, Component, mount, xml } from "../../src";
+import { App, Component, mount, onWillStart, useState, xml } from "../../src";
 import { status } from "../../src/runtime/status";
-import { makeTestFixture, snapshotEverything, nextTick, elem } from "../helpers";
+import {
+  makeTestFixture,
+  snapshotEverything,
+  nextTick,
+  elem,
+  useLogLifecycle,
+  makeDeferred,
+  nextMicroTick,
+} from "../helpers";
 
 let fixture: HTMLElement;
 
@@ -94,4 +102,44 @@ describe("app", () => {
     expect(iframeDoc.contains(div)).toBe(false);
     expect(status(comp)).toBe("destroyed");
   });
+
+  test("app: clear scheduler tasks and destroy cancelled nodes immediately on destroy", async () => {
+    let def = makeDeferred();
+    class B extends Component {
+      static template = xml`B`;
+      setup() {
+        useLogLifecycle();
+        onWillStart(() => def);
+      }
+    }
+    class A extends Component {
+      static template = xml`A<t t-if="state.value"><B/></t>`;
+      static components = { B };
+      state = useState({ value: false });
+      setup() {
+        useLogLifecycle();
+      }
+    }
+
+    const app = new App(A);
+    const comp = await app.mount(fixture);
+    expect(["A:setup", "A:willStart", "A:willRender", "A:rendered", "A:mounted"]).toBeLogged();
+
+    comp.state.value = true;
+    await nextTick();
+    expect(["A:willRender", "B:setup", "B:willStart", "A:rendered"]).toBeLogged();
+
+    // rerender to force the instantiation of a new B component (and cancelling the first)
+    comp.render();
+    await nextMicroTick();
+    expect(["A:willRender", "B:setup", "B:willStart", "A:rendered"]).toBeLogged();
+
+    app.destroy();
+    expect([
+      "A:willUnmount",
+      "B:willDestroy",
+      "A:willDestroy",
+      "B:willDestroy", // make sure the 2 B instances have been destroyed synchronously
+    ]).toBeLogged();
+  });
 });

tests/compiler/__snapshots__/event_handling.test.ts.snap

@@ -72,7 +72,7 @@ exports[`t-on can bind handlers with empty object (with non empty inner string)
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(['someval']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`action\`] = v_block2[i1];
+      ctx[\`action\`] = k_block2[i1];
       ctx[\`action_index\`] = i1;
       const key1 = ctx['action_index'];
       const v1 = ctx['activate'];
@@ -142,7 +142,7 @@ exports[`t-on handler is bound to proper owner, part 2 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList([1]);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`value\`] = v_block1[i1];
+      ctx[\`value\`] = k_block1[i1];
       const key1 = ctx['value'];
       let hdlr1 = [ctx['add'], ctx];
       c_block1[i1] = withKey(block2([hdlr1]), key1);
@@ -189,11 +189,11 @@ exports[`t-on handler is bound to proper owner, part 4 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList([1]);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`value\`] = v_block1[i1];
+      ctx[\`value\`] = k_block1[i1];
       ctx[\`value_first\`] = i1 === 0;
-      ctx[\`value_last\`] = i1 === v_block1.length - 1;
+      ctx[\`value_last\`] = i1 === k_block1.length - 1;
       ctx[\`value_index\`] = i1;
-      ctx[\`value_value\`] = k_block1[i1];
+      ctx[\`value_value\`] = v_block1[i1];
       const key1 = ctx['value'];
       c_block1[i1] = withKey(callTemplate_1.call(this, ctx, node, key + \`__1__\${key1}\`), key1);
     }
@@ -348,7 +348,7 @@ exports[`t-on t-on modifiers (native listener) t-on with prevent modifier in t-f
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['projects']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`project\`] = v_block2[i1];
+      ctx[\`project\`] = k_block2[i1];
       const key1 = ctx['project'];
       const v1 = ctx['onEdit'];
       const v2 = ctx['project'];

tests/compiler/__snapshots__/misc.test.ts.snap

@@ -33,7 +33,7 @@ exports[`misc complex template 1`] = `
     ctx = Object.create(ctx);
     const [k_block4, v_block4, l_block4, c_block4] = prepareList(ctx['batch'].slot_ids.filter(_slot=>_slot.build_id.id&&!_slot.trigger_id.manual&&(ctx['options'].trigger_display[_slot.trigger_id.id])));;
     for (let i1 = 0; i1 < l_block4; i1++) {
-      ctx[\`slot\`] = v_block4[i1];
+      ctx[\`slot\`] = k_block4[i1];
       const key1 = ctx['slot'].id;
       c_block4[i1] = withKey(comp1({class: ctx['slot_container'],slot: ctx['slot']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -42,7 +42,7 @@ exports[`misc complex template 1`] = `
     ctx = Object.create(ctx);
     const [k_block6, v_block6, l_block6, c_block6] = prepareList([1,2,3,4]);;
     for (let i1 = 0; i1 < l_block6; i1++) {
-      ctx[\`x\`] = v_block6[i1];
+      ctx[\`x\`] = k_block6[i1];
       const key1 = ctx['x'];
       c_block6[i1] = withKey(block7(), key1);
     }
@@ -51,7 +51,7 @@ exports[`misc complex template 1`] = `
     ctx = Object.create(ctx);
     const [k_block8, v_block8, l_block8, c_block8] = prepareList(ctx['commit_links']);;
     for (let i1 = 0; i1 < l_block8; i1++) {
-      ctx[\`commit_link\`] = v_block8[i1];
+      ctx[\`commit_link\`] = k_block8[i1];
       const key1 = ctx['commit_link'].id;
       let b10,b11,b12,b13;
       let attr5 = \`/runbot/commit/\${ctx['commit_link'].commit_id}\`;
@@ -99,11 +99,11 @@ exports[`misc global 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([4,5,6]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`value\`] = v_block2[i1];
+      ctx[\`value\`] = k_block2[i1];
       ctx[\`value_first\`] = i1 === 0;
-      ctx[\`value_last\`] = i1 === v_block2.length - 1;
+      ctx[\`value_last\`] = i1 === k_block2.length - 1;
       ctx[\`value_index\`] = i1;
-      ctx[\`value_value\`] = k_block2[i1];
+      ctx[\`value_value\`] = v_block2[i1];
       const key1 = ctx['value'];
       let txt1 = ctx['value'];
       const b4 = block4([txt1]);
@@ -223,7 +223,7 @@ exports[`misc other complex template 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['projects']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`project\`] = v_block2[i1];
+      ctx[\`project\`] = k_block2[i1];
       const key1 = ctx['project'].id;
       let hdlr1 = [ctx['selectProject'](ctx['project']), ctx];
       let txt2 = ctx['project'].name;
@@ -263,7 +263,7 @@ exports[`misc other complex template 1`] = `
       ctx = Object.create(ctx);
       const [k_block15, v_block15, l_block15, c_block15] = prepareList(ctx['categories']);;
       for (let i1 = 0; i1 < l_block15; i1++) {
-        ctx[\`category\`] = v_block15[i1];
+        ctx[\`category\`] = k_block15[i1];
         const key1 = ctx['category'].id;
         let attr6 = ctx['category'].id;
         let prop1 = new Boolean(ctx['category'].id==ctx['options'].active_category_id);
@@ -284,7 +284,7 @@ exports[`misc other complex template 1`] = `
       ctx = Object.create(ctx);
       const [k_block18, v_block18, l_block18, c_block18] = prepareList(ctx['triggers']);;
       for (let i1 = 0; i1 < l_block18; i1++) {
-        ctx[\`trigger\`] = v_block18[i1];
+        ctx[\`trigger\`] = k_block18[i1];
         const key1 = ctx['trigger'].id;
         let b20;
         if (!ctx['trigger'].manual&&ctx['trigger'].project_id===ctx['project'].id&&ctx['trigger'].category_id===ctx['options'].active_category_id) {

tests/compiler/__snapshots__/qweb_memory.test.ts.snap

@@ -12,7 +12,7 @@ exports[`memory t-foreach does not leak stuff in global scope 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([3,2,1]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       ctx[\`item_index\`] = i1;
       const key1 = ctx['item_index'];
       c_block2[i1] = withKey(text(ctx['item']), key1);

tests/compiler/__snapshots__/t_call.test.ts.snap

@@ -440,11 +440,11 @@ exports[`t-call (template calling) recursive template, part 2 2`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['node'].children||[]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`subtree\`] = v_block2[i1];
+      ctx[\`subtree\`] = k_block2[i1];
       ctx[\`subtree_first\`] = i1 === 0;
-      ctx[\`subtree_last\`] = i1 === v_block2.length - 1;
+      ctx[\`subtree_last\`] = i1 === k_block2.length - 1;
       ctx[\`subtree_index\`] = i1;
-      ctx[\`subtree_value\`] = k_block2[i1];
+      ctx[\`subtree_value\`] = v_block2[i1];
       const key1 = ctx['subtree_index'];
       ctx = Object.create(ctx);
       ctx[isBoundary] = 1;
@@ -495,11 +495,11 @@ exports[`t-call (template calling) recursive template, part 3 2`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['node'].children||[]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`subtree\`] = v_block2[i1];
+      ctx[\`subtree\`] = k_block2[i1];
       ctx[\`subtree_first\`] = i1 === 0;
-      ctx[\`subtree_last\`] = i1 === v_block2.length - 1;
+      ctx[\`subtree_last\`] = i1 === k_block2.length - 1;
       ctx[\`subtree_index\`] = i1;
-      ctx[\`subtree_value\`] = k_block2[i1];
+      ctx[\`subtree_value\`] = v_block2[i1];
       const key1 = ctx['subtree_index'];
       ctx = Object.create(ctx);
       ctx[isBoundary] = 1;
@@ -553,11 +553,11 @@ exports[`t-call (template calling) recursive template, part 4: with t-set recurs
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['node'].children||[]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`subtree\`] = v_block2[i1];
+      ctx[\`subtree\`] = k_block2[i1];
       ctx[\`subtree_first\`] = i1 === 0;
-      ctx[\`subtree_last\`] = i1 === v_block2.length - 1;
+      ctx[\`subtree_last\`] = i1 === k_block2.length - 1;
       ctx[\`subtree_index\`] = i1;
-      ctx[\`subtree_value\`] = k_block2[i1];
+      ctx[\`subtree_value\`] = v_block2[i1];
       const key1 = ctx['subtree_index'];
       ctx = Object.create(ctx);
       ctx[isBoundary] = 1;
@@ -813,11 +813,11 @@ exports[`t-call (template calling) t-call with t-set inside and outside 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['list']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`v\`] = v_block2[i1];
+      ctx[\`v\`] = k_block2[i1];
       ctx[\`v_first\`] = i1 === 0;
-      ctx[\`v_last\`] = i1 === v_block2.length - 1;
+      ctx[\`v_last\`] = i1 === k_block2.length - 1;
       ctx[\`v_index\`] = i1;
-      ctx[\`v_value\`] = k_block2[i1];
+      ctx[\`v_value\`] = v_block2[i1];
       const key1 = ctx['v_index'];
       setContextValue(ctx, \\"val\\", ctx['v'].val);
       ctx = Object.create(ctx);
@@ -880,11 +880,11 @@ exports[`t-call (template calling) t-call with t-set inside and outside. 2 2`] =
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['list']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`v\`] = v_block2[i1];
+      ctx[\`v\`] = k_block2[i1];
       ctx[\`v_first\`] = i1 === 0;
-      ctx[\`v_last\`] = i1 === v_block2.length - 1;
+      ctx[\`v_last\`] = i1 === k_block2.length - 1;
       ctx[\`v_index\`] = i1;
-      ctx[\`v_value\`] = k_block2[i1];
+      ctx[\`v_value\`] = v_block2[i1];
       const key1 = ctx['v_index'];
       setContextValue(ctx, \\"val\\", ctx['v'].val);
       ctx = Object.create(ctx);

tests/compiler/__snapshots__/t_foreach.test.ts.snap

@@ -12,7 +12,7 @@ exports[`t-foreach does not pollute the rendering context 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([1]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       c_block2[i1] = withKey(text(ctx['item']), key1);
     }
@@ -35,7 +35,7 @@ exports[`t-foreach iterate on items (on a element node) 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([1,2]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       let txt1 = ctx['item'];
       c_block2[i1] = withKey(block3([txt1]), key1);
@@ -58,9 +58,9 @@ exports[`t-foreach iterate on items 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([3,2,1]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       ctx[\`item_index\`] = i1;
-      ctx[\`item_value\`] = k_block2[i1];
+      ctx[\`item_value\`] = v_block2[i1];
       const key1 = ctx['item'];
       const b4 = text(\` [\`);
       const b5 = text(ctx['item_index']);
@@ -77,6 +77,62 @@ exports[`t-foreach iterate on items 1`] = `
 }"
 `;
 
+exports[`t-foreach iterate, Map param 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['value']);;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`item\`] = k_block1[i1];
+      ctx[\`item_index\`] = i1;
+      ctx[\`item_value\`] = v_block1[i1];
+      const key1 = ctx['item_index'];
+      const b3 = text(\` [\`);
+      const b4 = text(ctx['item_index']);
+      const b5 = text(\`: \`);
+      const b6 = text(ctx['item']);
+      const b7 = text(\` \`);
+      const b8 = text(ctx['item_value']);
+      const b9 = text(\`] \`);
+      c_block1[i1] = withKey(multi([b3, b4, b5, b6, b7, b8, b9]), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
+exports[`t-foreach iterate, Set param 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['value']);;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`item\`] = k_block1[i1];
+      ctx[\`item_index\`] = i1;
+      ctx[\`item_value\`] = v_block1[i1];
+      const key1 = ctx['item_index'];
+      const b3 = text(\` [\`);
+      const b4 = text(ctx['item_index']);
+      const b5 = text(\`: \`);
+      const b6 = text(ctx['item']);
+      const b7 = text(\` \`);
+      const b8 = text(ctx['item_value']);
+      const b9 = text(\`] \`);
+      c_block1[i1] = withKey(multi([b3, b4, b5, b6, b7, b8, b9]), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
 exports[`t-foreach iterate, dict param 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -89,9 +145,9 @@ exports[`t-foreach iterate, dict param 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['value']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       ctx[\`item_index\`] = i1;
-      ctx[\`item_value\`] = k_block2[i1];
+      ctx[\`item_value\`] = v_block2[i1];
       const key1 = ctx['item_index'];
       const b4 = text(\` [\`);
       const b5 = text(ctx['item_index']);
@@ -108,6 +164,62 @@ exports[`t-foreach iterate, dict param 1`] = `
 }"
 `;
 
+exports[`t-foreach iterate, generator param 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['gen']());;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`item\`] = k_block1[i1];
+      ctx[\`item_index\`] = i1;
+      ctx[\`item_value\`] = v_block1[i1];
+      const key1 = ctx['item_index'];
+      const b3 = text(\` [\`);
+      const b4 = text(ctx['item_index']);
+      const b5 = text(\`: \`);
+      const b6 = text(ctx['item']);
+      const b7 = text(\` \`);
+      const b8 = text(ctx['item_value']);
+      const b9 = text(\`] \`);
+      c_block1[i1] = withKey(multi([b3, b4, b5, b6, b7, b8, b9]), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
+exports[`t-foreach iterate, iterable param 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  
+  return function template(ctx, node, key = \\"\\") {
+    ctx = Object.create(ctx);
+    const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['map'].values());;
+    for (let i1 = 0; i1 < l_block1; i1++) {
+      ctx[\`item\`] = k_block1[i1];
+      ctx[\`item_index\`] = i1;
+      ctx[\`item_value\`] = v_block1[i1];
+      const key1 = ctx['item_index'];
+      const b3 = text(\` [\`);
+      const b4 = text(ctx['item_index']);
+      const b5 = text(\`: \`);
+      const b6 = text(ctx['item']);
+      const b7 = text(\` \`);
+      const b8 = text(ctx['item_value']);
+      const b9 = text(\`] \`);
+      c_block1[i1] = withKey(multi([b3, b4, b5, b6, b7, b8, b9]), key1);
+    }
+    return list(c_block1);
+  }
+}"
+`;
+
 exports[`t-foreach iterate, position 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -120,9 +232,9 @@ exports[`t-foreach iterate, position 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Array(5));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`elem\`] = v_block2[i1];
+      ctx[\`elem\`] = k_block2[i1];
       ctx[\`elem_first\`] = i1 === 0;
-      ctx[\`elem_last\`] = i1 === v_block2.length - 1;
+      ctx[\`elem_last\`] = i1 === k_block2.length - 1;
       ctx[\`elem_index\`] = i1;
       const key1 = ctx['elem'];
       let b4,b5,b6,b7,b8,b9;
@@ -156,7 +268,7 @@ exports[`t-foreach simple iteration (in a node) 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([3,2,1]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       c_block2[i1] = withKey(text(ctx['item']), key1);
     }
@@ -176,7 +288,7 @@ exports[`t-foreach simple iteration 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList([3,2,1]);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`item\`] = v_block1[i1];
+      ctx[\`item\`] = k_block1[i1];
       const key1 = ctx['item'];
       c_block1[i1] = withKey(text(ctx['item']), key1);
     }
@@ -198,7 +310,7 @@ exports[`t-foreach simple iteration with two nodes inside 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList([3,2,1]);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`item\`] = v_block1[i1];
+      ctx[\`item\`] = k_block1[i1];
       const key1 = ctx['item'];
       let txt1 = ctx['item'];
       const b3 = block3([txt1]);
@@ -227,20 +339,20 @@ exports[`t-foreach t-call with body in t-foreach in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['numbers']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`a\`] = v_block2[i1];
+      ctx[\`a\`] = k_block2[i1];
       ctx[\`a_first\`] = i1 === 0;
-      ctx[\`a_last\`] = i1 === v_block2.length - 1;
+      ctx[\`a_last\`] = i1 === k_block2.length - 1;
       ctx[\`a_index\`] = i1;
-      ctx[\`a_value\`] = k_block2[i1];
+      ctx[\`a_value\`] = v_block2[i1];
       const key1 = ctx['a'];
       ctx = Object.create(ctx);
       const [k_block4, v_block4, l_block4, c_block4] = prepareList(ctx['letters']);;
       for (let i2 = 0; i2 < l_block4; i2++) {
-        ctx[\`b\`] = v_block4[i2];
+        ctx[\`b\`] = k_block4[i2];
         ctx[\`b_first\`] = i2 === 0;
-        ctx[\`b_last\`] = i2 === v_block4.length - 1;
+        ctx[\`b_last\`] = i2 === k_block4.length - 1;
         ctx[\`b_index\`] = i2;
-        ctx[\`b_value\`] = k_block4[i2];
+        ctx[\`b_value\`] = v_block4[i2];
         const key2 = ctx['b'];
         ctx = Object.create(ctx);
         ctx[isBoundary] = 1;
@@ -296,20 +408,20 @@ exports[`t-foreach t-call without body in t-foreach in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['numbers']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`a\`] = v_block2[i1];
+      ctx[\`a\`] = k_block2[i1];
       ctx[\`a_first\`] = i1 === 0;
-      ctx[\`a_last\`] = i1 === v_block2.length - 1;
+      ctx[\`a_last\`] = i1 === k_block2.length - 1;
       ctx[\`a_index\`] = i1;
-      ctx[\`a_value\`] = k_block2[i1];
+      ctx[\`a_value\`] = v_block2[i1];
       const key1 = ctx['a'];
       ctx = Object.create(ctx);
       const [k_block4, v_block4, l_block4, c_block4] = prepareList(ctx['letters']);;
       for (let i2 = 0; i2 < l_block4; i2++) {
-        ctx[\`b\`] = v_block4[i2];
+        ctx[\`b\`] = k_block4[i2];
         ctx[\`b_first\`] = i2 === 0;
-        ctx[\`b_last\`] = i2 === v_block4.length - 1;
+        ctx[\`b_last\`] = i2 === k_block4.length - 1;
         ctx[\`b_index\`] = i2;
-        ctx[\`b_value\`] = k_block4[i2];
+        ctx[\`b_value\`] = v_block4[i2];
         const key2 = ctx['b'];
         c_block4[i2] = withKey(callTemplate_1.call(this, ctx, node, key + \`__1__\${key1}__\${key2}\`), key2);
       }
@@ -363,12 +475,12 @@ exports[`t-foreach t-foreach in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['numbers']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`number\`] = v_block2[i1];
+      ctx[\`number\`] = k_block2[i1];
       const key1 = ctx['number'];
       ctx = Object.create(ctx);
       const [k_block3, v_block3, l_block3, c_block3] = prepareList(ctx['letters']);;
       for (let i2 = 0; i2 < l_block3; i2++) {
-        ctx[\`letter\`] = v_block3[i2];
+        ctx[\`letter\`] = k_block3[i2];
         const key2 = ctx['letter'];
         const b5 = text(\` [\`);
         const b6 = text(ctx['number']);
@@ -397,7 +509,7 @@ exports[`t-foreach t-foreach with t-if inside (no external node) 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['elems']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem\`] = k_block1[i1];
       const key1 = ctx['elem'].id;
       let b3;
       if (ctx['elem'].id<3) {
@@ -424,7 +536,7 @@ exports[`t-foreach t-foreach with t-if inside 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['elems']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`elem\`] = v_block2[i1];
+      ctx[\`elem\`] = k_block2[i1];
       const key1 = ctx['elem'].id;
       let b4;
       if (ctx['elem'].id<3) {
@@ -452,7 +564,7 @@ exports[`t-foreach t-key on t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['things']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`thing\`] = v_block2[i1];
+      ctx[\`thing\`] = k_block2[i1];
       const key1 = ctx['thing'];
       c_block2[i1] = withKey(block3(), key1);
     }
@@ -475,7 +587,7 @@ exports[`t-foreach throws error if invalid loop expression 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['abc']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       ctx[\`item_index\`] = i1;
       const key1 = ctx['item'];
       const tKey_1 = ctx['item_index'];
@@ -502,7 +614,7 @@ exports[`t-foreach with t-memo 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'].id;
       const memo1 = [ctx['item'].x];
       const vnode1 = cache[key1];;

tests/compiler/__snapshots__/t_key.test.ts.snap

@@ -58,7 +58,7 @@ exports[`t-key t-key directive in a list 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['beers']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`beer\`] = v_block2[i1];
+      ctx[\`beer\`] = k_block2[i1];
       const key1 = ctx['beer'].id;
       let txt1 = ctx['beer'].name;
       c_block2[i1] = withKey(block3([txt1]), key1);

tests/compiler/__snapshots__/t_ref.test.ts.snap

@@ -105,7 +105,7 @@ exports[`t-ref refs in a loop 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       const tKey_1 = ctx['item'];
       const v1 = ctx['item'];

tests/compiler/__snapshots__/t_set.test.ts.snap

@@ -351,7 +351,7 @@ exports[`t-set t-set outside modified in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(['a','b']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       const key1 = ctx['val'];
       let txt1 = ctx['iter'];
       c_block2[i1] = withKey(block3([txt1]), key1);
@@ -381,7 +381,7 @@ exports[`t-set t-set outside modified in t-foreach increment-after operator 1`]
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(['a','b']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       const key1 = ctx['val'];
       let txt1 = ctx['iter'];
       c_block2[i1] = withKey(block3([txt1]), key1);
@@ -411,7 +411,7 @@ exports[`t-set t-set outside modified in t-foreach increment-before operator 1`]
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(['a','b']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       const key1 = ctx['val'];
       let txt1 = ctx['iter'];
       c_block2[i1] = withKey(block3([txt1]), key1);
@@ -441,7 +441,7 @@ exports[`t-set t-set should reuse variable if possible 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['list']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`elem\`] = v_block2[i1];
+      ctx[\`elem\`] = k_block2[i1];
       ctx[\`elem_index\`] = i1;
       const key1 = ctx['elem_index'];
       let txt1 = ctx['v'];

tests/compiler/parser.test.ts

@@ -1569,6 +1569,12 @@ describe("qweb parser", () => {
     );
   });
 
+  test("component with t-out", async () => {
+    expect(parse(`<MyComponent t-out="someValue"/>`)).toEqual(
+      parse(`<MyComponent><t t-out="someValue"/></MyComponent>`)
+    );
+  });
+
   test("component with t-esc and content", async () => {
     expect(() => parse(`<MyComponent t-esc="someValue">Some content</MyComponent>`)).toThrow(
       "Cannot have t-esc on a component that already has content"

tests/compiler/t_foreach.test.ts

@@ -105,6 +105,64 @@ describe("t-foreach", () => {
     expect(renderToString(template, context)).toBe(expected);
   });
 
+  test("iterate, Map param", () => {
+    const template = `
+      <t t-foreach="value" t-as="item" t-key="item_index">
+        [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
+      </t>`;
+    const expected = ` [0: a 1]  [1: b 2]  [2: c 3] `;
+    const context = {
+      value: new Map([
+        ["a", 1],
+        ["b", 2],
+        ["c", 3],
+      ]),
+    };
+    expect(renderToString(template, context)).toBe(expected);
+  });
+
+  test("iterate, Set param", () => {
+    const template = `
+      <t t-foreach="value" t-as="item" t-key="item_index">
+        [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
+      </t>`;
+    const expected = ` [0: 1 1]  [1: 2 2]  [2: 3 3] `;
+    const context = { value: new Set([1, 2, 3]) };
+    expect(renderToString(template, context)).toBe(expected);
+  });
+
+  test("iterate, iterable param", () => {
+    const template = `
+      <t t-foreach="map.values()" t-as="item" t-key="item_index">
+        [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
+      </t>`;
+    const expected = ` [0: 1 1]  [1: 2 2]  [2: 3 3] `;
+    const context = {
+      map: new Map([
+        ["a", 1],
+        ["b", 2],
+        ["c", 3],
+      ]),
+    };
+    expect(renderToString(template, context)).toBe(expected);
+  });
+
+  test("iterate, generator param", () => {
+    const template = `
+      <t t-foreach="gen()" t-as="item" t-key="item_index">
+        [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
+      </t>`;
+    const expected = ` [0: 1 1]  [1: 2 2]  [2: 3 3] `;
+    const context = {
+      *gen() {
+        yield 1;
+        yield 2;
+        yield 3;
+      },
+    };
+    expect(renderToString(template, context)).toBe(expected);
+  });
+
   test("does not pollute the rendering context", () => {
     const template = `
         <div>
@@ -193,7 +251,9 @@ describe("t-foreach", () => {
 
   test("throws error if invalid loop expression", () => {
     const test = `<div><t t-foreach="abc" t-as="item" t-key="item"><span t-key="item_index"/></t></div>`;
-    expect(() => renderToString(test)).toThrow("Invalid loop expression");
+    expect(() => renderToString(test)).toThrow(
+      'Invalid loop expression: "undefined" is not iterable'
+    );
   });
 
   test("t-foreach with t-if inside", () => {

tests/compiler/validation.test.ts

@@ -37,4 +37,22 @@ describe("basic validation", () => {
     const template = `<div t-best-beer="rochefort 10">test</div>`;
     expect(() => renderToString(template)).toThrow("Unknown QWeb directive: 't-best-beer'");
   });
+
+  test("compilation error", () => {
+    const template = `<div t-att-class="a b">test</div>`;
+    expect(() => renderToString(template))
+      .toThrow(`Failed to compile anonymous template: Unexpected identifier
+
+generated code:
+function(app, bdom, helpers) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0="class">test</div>\`);
+  
+  return function template(ctx, node, key = "") {
+    let attr1 = ctx['a']ctx['b'];
+    return block1([attr1]);
+  }
+}`);
+  });
 });

tests/components/__snapshots__/basics.test.ts.snap

@@ -492,7 +492,7 @@ exports[`basics list of two sub components inside other nodes 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].blips);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`blip\`] = v_block2[i1];
+      ctx[\`blip\`] = k_block2[i1];
       const key1 = ctx['blip'].id;
       const b4 = comp1({}, key + \`__1__\${key1}\`, node, this, null);
       const b5 = comp2({}, key + \`__2__\${key1}\`, node, this, null);
@@ -1084,7 +1084,7 @@ exports[`basics updating a component with t-foreach as root 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`item\`] = v_block1[i1];
+      ctx[\`item\`] = k_block1[i1];
       const key1 = ctx['item'];
       c_block1[i1] = withKey(text(ctx['item']), key1);
     }
@@ -1135,7 +1135,7 @@ exports[`basics widget after a t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Array(2));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`elem\`] = v_block2[i1];
+      ctx[\`elem\`] = k_block2[i1];
       ctx[\`elem_index\`] = i1;
       const key1 = ctx['elem_index'];
       c_block2[i1] = withKey(text(\`txt\`), key1);
@@ -1282,7 +1282,7 @@ exports[`t-out in components can render list of t-out  1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].items);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       const b4 = text(ctx['item']);
       const b5 = safeOutput(ctx['item']);

tests/components/__snapshots__/concurrency.test.ts.snap

@@ -13,7 +13,7 @@ exports[`Cascading renders after microtaskTick 1`] = `
     ctx = Object.create(ctx);
     const [k_block4, v_block4, l_block4, c_block4] = prepareList(ctx['state']);;
     for (let i1 = 0; i1 < l_block4; i1++) {
-      ctx[\`elem\`] = v_block4[i1];
+      ctx[\`elem\`] = k_block4[i1];
       const key1 = ctx['elem'].id;
       c_block4[i1] = withKey(text(ctx['elem'].id), key1);
     }
@@ -34,7 +34,7 @@ exports[`Cascading renders after microtaskTick 2`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['state']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem\`] = k_block1[i1];
       const key1 = ctx['elem'].id;
       c_block1[i1] = withKey(comp1({id: ctx['elem'].id}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -1901,7 +1901,7 @@ exports[`t-foreach with dynamic async component 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['list']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`arr\`] = v_block1[i1];
+      ctx[\`arr\`] = k_block1[i1];
       ctx[\`arr_index\`] = i1;
       const key1 = ctx['arr_index'];
       let b3;

tests/components/__snapshots__/error_handling.test.ts.snap

@@ -12,6 +12,18 @@ exports[`basics display a nice error if a component is not a component 1`] = `
 }"
 `;
 
+exports[`basics display a nice error if a non-root component template fails to compile 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return comp1({}, key + \`__1\`, node, this, null);
+  }
+}"
+`;
+
 exports[`basics display a nice error if it cannot find component (in dev mode) 1`] = `
 "function anonymous(app, bdom, helpers
 ) {
@@ -938,7 +950,7 @@ exports[`can catch errors catching error, rethrow, render parent  -- a main comp
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(Object.values(ctx['state'].cps));;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`cp\`] = v_block1[i1];
+      ctx[\`cp\`] = k_block1[i1];
       const key1 = ctx['cp'].id;
       const v1 = ctx['this'];
       const v2 = ctx['cp'];
@@ -1017,7 +1029,7 @@ exports[`can catch errors catching in child makes parent render 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(Object.entries(ctx['this'].elements));;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem\`] = k_block1[i1];
       const key1 = ctx['elem'][0];
       const v1 = ctx['this'];
       const v2 = ctx['elem'];

tests/components/__snapshots__/event_handling.test.ts.snap

@@ -117,7 +117,7 @@ exports[`event handling objects from scope are properly captured by t-on 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       const v1 = ctx['onClick'];
       const v2 = ctx['item'];
@@ -158,7 +158,7 @@ exports[`event handling t-on with handler bound to dynamic argument on a t-forea
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = ctx['item'];
       const v1 = ctx['onClick'];
       const v2 = ctx['item'];

tests/components/__snapshots__/props.test.ts.snap

@@ -11,7 +11,7 @@ exports[`.alike suffix in a list 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['state'].elems);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem\`] = k_block1[i1];
       const key1 = ctx['elem'].id;
       const v1 = ctx['this'];
       const v2 = ctx['elem'];
@@ -106,7 +106,7 @@ exports[`basics arrow functions as prop correctly capture their scope 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`item\`] = v_block1[i1];
+      ctx[\`item\`] = k_block1[i1];
       const key1 = ctx['item'].val;
       const v1 = ctx['onClick'];
       const v2 = ctx['item'];

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

@@ -2140,7 +2140,7 @@ exports[`slots slot in t-foreach locations 2`] = `
     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\`] = k_block1[i1];
       ctx[\`elem_index\`] = i1;
       const key1 = ctx['elem_index'];
       let txt1 = ctx['elem'];
@@ -2430,7 +2430,7 @@ exports[`slots slots are rendered with proper context, part 2 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].users);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`user\`] = v_block2[i1];
+      ctx[\`user\`] = k_block2[i1];
       const key1 = ctx['user'].id;
       const ctx1 = capture(ctx);
       const b7 = comp1({to: '/user/'+ctx['user'].id,slots: markRaw({'default': {__render: slot1.bind(this), __ctx: ctx1}})}, key + \`__1__\${key1}\`, node, this, null);
@@ -2478,7 +2478,7 @@ exports[`slots slots are rendered with proper context, part 3 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].users);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`user\`] = v_block2[i1];
+      ctx[\`user\`] = k_block2[i1];
       const key1 = ctx['user'].id;
       setContextValue(ctx, \\"userdescr\\", 'User '+ctx['user'].name);
       const ctx1 = capture(ctx);
@@ -2625,7 +2625,7 @@ exports[`slots slots in t-foreach and re-rendering 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Array(2));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`n\`] = v_block2[i1];
+      ctx[\`n\`] = k_block2[i1];
       ctx[\`n_index\`] = i1;
       const key1 = ctx['n_index'];
       const ctx1 = capture(ctx);
@@ -2674,14 +2674,14 @@ exports[`slots slots in t-foreach in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['tree']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`node1\`] = v_block2[i1];
+      ctx[\`node1\`] = k_block2[i1];
       const key1 = ctx['node1'].key;
       let txt1 = ctx['node1'].value;
       const b4 = block4([txt1]);
       ctx = Object.create(ctx);
       const [k_block6, v_block6, l_block6, c_block6] = prepareList(ctx['node1'].nodes);;
       for (let i2 = 0; i2 < l_block6; i2++) {
-        ctx[\`node2\`] = v_block6[i2];
+        ctx[\`node2\`] = k_block6[i2];
         const key2 = ctx['node2'].key;
         const ctx1 = capture(ctx);
         c_block6[i2] = withKey(comp1({slots: markRaw({'default': {__render: slot1.bind(this), __ctx: ctx1}})}, key + \`__1__\${key1}__\${key2}\`, node, this, null), key2);
@@ -2731,7 +2731,7 @@ exports[`slots slots in t-foreach with t-set and re-rendering 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Array(2));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`n\`] = v_block2[i1];
+      ctx[\`n\`] = k_block2[i1];
       ctx[\`n_index\`] = i1;
       const key1 = ctx['n_index'];
       setContextValue(ctx, \\"dummy\\", ctx['n_index']);
@@ -2881,11 +2881,11 @@ exports[`slots t-slot in recursive templates 1`] = `
     ctx = Object.create(ctx);
     const [k_block3, v_block3, l_block3, c_block3] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block3; i1++) {
-      ctx[\`item\`] = v_block3[i1];
+      ctx[\`item\`] = k_block3[i1];
       ctx[\`item_first\`] = i1 === 0;
-      ctx[\`item_last\`] = i1 === v_block3.length - 1;
+      ctx[\`item_last\`] = i1 === k_block3.length - 1;
       ctx[\`item_index\`] = i1;
-      ctx[\`item_value\`] = k_block3[i1];
+      ctx[\`item_value\`] = v_block3[i1];
       const key1 = ctx['item'].name;
       let b5,b6;
       if (!ctx['item'].children.length) {

tests/components/__snapshots__/t_call.test.ts.snap

@@ -415,11 +415,11 @@ exports[`t-call t-call in t-foreach and children component 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(['a','b','c']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       ctx[\`val_first\`] = i1 === 0;
-      ctx[\`val_last\`] = i1 === v_block2.length - 1;
+      ctx[\`val_last\`] = i1 === k_block2.length - 1;
       ctx[\`val_index\`] = i1;
-      ctx[\`val_value\`] = k_block2[i1];
+      ctx[\`val_value\`] = v_block2[i1];
       const key1 = ctx['val'];
       c_block2[i1] = withKey(callTemplate_1.call(this, ctx, node, key + \`__1__\${key1}\`), key1);
     }

tests/components/__snapshots__/t_foreach.test.ts.snap

@@ -14,7 +14,7 @@ exports[`list of components components in a node in a t-foreach  1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['items']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`item\`] = v_block2[i1];
+      ctx[\`item\`] = k_block2[i1];
       const key1 = 'li_'+ctx['item'];
       const b4 = comp1({item: ctx['item']}, key + \`__1__\${key1}\`, node, this, null);
       c_block2[i1] = withKey(block3([], [b4]), key1);
@@ -51,7 +51,7 @@ exports[`list of components crash on duplicate key in dev mode 1`] = `
     const [k_block1, v_block1, l_block1, c_block1] = prepareList([1,2]);;
     const keys1 = new Set();
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`item\`] = v_block1[i1];
+      ctx[\`item\`] = k_block1[i1];
       const key1 = 'child';
       if (keys1.has(String(key1))) { throw new OwlError(\`Got duplicate key in t-foreach: \${key1}\`)}
       keys1.add(String(key1));
@@ -87,7 +87,7 @@ exports[`list of components crash when using object as keys that serialize to th
     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];
+      ctx[\`item\`] = k_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));
@@ -125,7 +125,7 @@ exports[`list of components list of sub components inside other nodes 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].blips);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`blip\`] = v_block2[i1];
+      ctx[\`blip\`] = k_block2[i1];
       const key1 = ctx['blip'].id;
       const b4 = comp1({}, key + \`__1__\${key1}\`, node, this, null);
       c_block2[i1] = withKey(block3([], [b4]), key1);
@@ -191,7 +191,7 @@ exports[`list of components order is correct when slots are not of same type 2`]
     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];
+      ctx[\`slotName\`] = k_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);
@@ -214,13 +214,13 @@ exports[`list of components reconciliation alg works for t-foreach in t-foreach
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].s);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`section\`] = v_block2[i1];
+      ctx[\`section\`] = k_block2[i1];
       ctx[\`section_index\`] = i1;
       const key1 = ctx['section_index'];
       ctx = Object.create(ctx);
       const [k_block3, v_block3, l_block3, c_block3] = prepareList(ctx['section'].blips);;
       for (let i2 = 0; i2 < l_block3; i2++) {
-        ctx[\`blip\`] = v_block3[i2];
+        ctx[\`blip\`] = k_block3[i2];
         ctx[\`blip_index\`] = i2;
         const key2 = ctx['blip_index'];
         c_block3[i2] = withKey(comp1({blip: ctx['blip']}, key + \`__1__\${key1}__\${key2}\`, node, this, null), key2);
@@ -263,12 +263,12 @@ exports[`list of components reconciliation alg works for t-foreach in t-foreach,
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].rows);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`row\`] = v_block2[i1];
+      ctx[\`row\`] = k_block2[i1];
       const key1 = ctx['row'];
       ctx = Object.create(ctx);
       const [k_block4, v_block4, l_block4, c_block4] = prepareList(ctx['state'].cols);;
       for (let i2 = 0; i2 < l_block4; i2++) {
-        ctx[\`col\`] = v_block4[i2];
+        ctx[\`col\`] = k_block4[i2];
         const key2 = ctx['col'];
         const b6 = comp1({row: ctx['row'],col: ctx['col']}, key + \`__1__\${key1}__\${key2}\`, node, this, null);
         c_block4[i2] = withKey(block5([], [b6]), key2);
@@ -308,7 +308,7 @@ exports[`list of components simple list 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['state'].elems);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`elem\`] = v_block1[i1];
+      ctx[\`elem\`] = k_block1[i1];
       const key1 = ctx['elem'].id;
       c_block1[i1] = withKey(comp1({value: ctx['elem'].value}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -344,7 +344,7 @@ exports[`list of components sub components rendered in a loop 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].numbers);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`number\`] = v_block2[i1];
+      ctx[\`number\`] = k_block2[i1];
       const key1 = ctx['number'];
       c_block2[i1] = withKey(comp1({n: ctx['number']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -381,7 +381,7 @@ exports[`list of components sub components with some state rendered in a loop 1`
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].numbers);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`number\`] = v_block2[i1];
+      ctx[\`number\`] = k_block2[i1];
       const key1 = ctx['number'];
       c_block2[i1] = withKey(comp1({}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -418,7 +418,7 @@ exports[`list of components switch component position 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['clist']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`c\`] = v_block2[i1];
+      ctx[\`c\`] = k_block2[i1];
       const key1 = ctx['c'];
       c_block2[i1] = withKey(comp1({key: ctx['c']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
@@ -455,7 +455,7 @@ exports[`list of components t-foreach with t-component, and update 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(Array(2));;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`n\`] = v_block2[i1];
+      ctx[\`n\`] = k_block2[i1];
       ctx[\`n_index\`] = i1;
       const key1 = ctx['n_index'];
       c_block2[i1] = withKey(comp1({val: ctx['n_index']}, key + \`__1__\${key1}\`, node, this, null), key1);

tests/components/__snapshots__/t_key.test.ts.snap

@@ -13,7 +13,7 @@ exports[`t-key t-foreach with t-key switch component position 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['clist']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`c\`] = v_block2[i1];
+      ctx[\`c\`] = k_block2[i1];
       const key1 = ctx['c'];
       const tKey_1 = ctx['key1'];
       c_block2[i1] = withKey(comp1({key: ctx['c']+ctx['key1']}, tKey_1 + key + \`__1__\${key1}\`, node, this, null), tKey_1 + key1);

tests/components/__snapshots__/t_model.test.ts.snap

@@ -196,7 +196,7 @@ exports[`t-model directive in a t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`thing\`] = v_block2[i1];
+      ctx[\`thing\`] = k_block2[i1];
       const key1 = ctx['thing'].id;
       const bExpr1 = ctx['thing'];
       const expr1 = 'f';
@@ -223,7 +223,7 @@ exports[`t-model directive in a t-foreach, part 2 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`thing\`] = v_block2[i1];
+      ctx[\`thing\`] = k_block2[i1];
       ctx[\`thing_index\`] = i1;
       const key1 = ctx['thing_index'];
       const bExpr1 = ctx['state'];
@@ -251,7 +251,7 @@ exports[`t-model directive in a t-foreach, part 3 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['names']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`name\`] = v_block2[i1];
+      ctx[\`name\`] = k_block2[i1];
       ctx[\`name_index\`] = i1;
       const key1 = ctx['name_index'];
       const bExpr1 = ctx['state'].values;
@@ -485,7 +485,7 @@ exports[`t-model directive t-model with dynamic number values on select options
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].options);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`o\`] = v_block2[i1];
+      ctx[\`o\`] = k_block2[i1];
       const key1 = ctx['o'].value;
       let attr1 = ctx['o'].value;
       let attr2 = bValue1 === ctx['o'].value;
@@ -586,7 +586,7 @@ exports[`t-model directive t-model with dynamic values on select options in fore
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['options']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`v\`] = v_block2[i1];
+      ctx[\`v\`] = k_block2[i1];
       const key1 = ctx['v'];
       let attr1 = ctx['v'];
       let attr2 = bValue1 === ctx['v'];
@@ -613,7 +613,7 @@ exports[`t-model directive t-model with radio button group in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['options']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`opt\`] = v_block2[i1];
+      ctx[\`opt\`] = k_block2[i1];
       const key1 = ctx['opt'];
       let prop1 = new String((ctx['opt']) === 0 ? 0 : ((ctx['opt']) || \\"\\"));
       let attr1 = ctx['opt'];

tests/components/__snapshots__/t_on.test.ts.snap

@@ -16,7 +16,7 @@ exports[`t-on t-on expression captured in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['arr']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       const key1 = ctx['val'];
       const v1 = ctx['otherState'];
       const v2 = ctx['iter'];
@@ -43,7 +43,7 @@ exports[`t-on t-on expression in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].values);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       ctx[\`val_index\`] = i1;
       const key1 = ctx['val'];
       let txt1 = ctx['val_index'];
@@ -75,7 +75,7 @@ exports[`t-on t-on expression in t-foreach with t-set 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].values);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       ctx[\`val_index\`] = i1;
       const key1 = ctx['val'];
       setContextValue(ctx, \\"bossa\\", ctx['bossa']+'_'+ctx['val_index']);
@@ -106,7 +106,7 @@ exports[`t-on t-on method call in t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['state'].values);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`val\`] = v_block2[i1];
+      ctx[\`val\`] = k_block2[i1];
       ctx[\`val_index\`] = i1;
       const key1 = ctx['val'];
       let txt1 = ctx['val_index'];
@@ -196,7 +196,7 @@ exports[`t-on t-on on components and t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(['John','Raoul','Gérald']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`name\`] = v_block1[i1];
+      ctx[\`name\`] = k_block1[i1];
       const key1 = ctx['name'];
       const v1 = ctx['this'];
       const v2 = ctx['name'];
@@ -493,7 +493,7 @@ exports[`t-on t-on when first component child is an empty component 2`] = `
     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[\`c\`] = v_block1[i1];
+      ctx[\`c\`] = k_block1[i1];
       ctx[\`c_index\`] = i1;
       const key1 = ctx['c_index'];
       let txt1 = ctx['c'];

tests/components/__snapshots__/t_out.test.ts.snap

@@ -17,7 +17,7 @@ exports[`components in t-out simple list 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];
+      ctx[\`n\`] = k_block1[i1];
       const key1 = ctx['n'];
       ctx[\`blabla\`] = new LazyValue(value1, ctx, this, node, key1);
       c_block1[i1] = withKey(safeOutput(ctx['blabla']), key1);

tests/components/error_handling.test.ts

@@ -20,7 +20,7 @@ import {
   useLogLifecycle,
   nextAppError,
 } from "../helpers";
-import { OwlError } from "../../src/runtime/error_handling";
+import { OwlError } from "../../src/common/owl_error";
 
 let fixture: HTMLElement;
 
@@ -143,6 +143,66 @@ describe("basics", () => {
     );
   });
 
+  test("display a nice error if the root component template fails to compile", async () => {
+    // This is a special case: mount throws synchronously and we don't have any
+    // node which can handle the error, hence the different structure of this test
+    class Comp extends Component {
+      static template = xml`<div t-att-class="a b">test</div>`;
+    }
+    const app = new App(Comp);
+    let error: Error;
+    try {
+      await app.mount(fixture);
+    } catch (e) {
+      error = e as Error;
+    }
+    const expectedErrorMessage = `Failed to compile anonymous template: Unexpected identifier
+
+generated code:
+function(app, bdom, helpers) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0="class">test</div>\`);
+  
+  return function template(ctx, node, key = "") {
+    let attr1 = ctx['a']ctx['b'];
+    return block1([attr1]);
+  }
+}`;
+    expect(error!).toBeDefined();
+    expect(error!.message).toBe(expectedErrorMessage);
+  });
+
+  test("display a nice error if a non-root component template fails to compile", async () => {
+    class Child extends Component {
+      static template = xml`<div t-att-class="a b">test</div>`;
+    }
+    class Parent extends Component {
+      static components = { Child };
+      static template = xml`<Child/>`;
+    }
+    const expectedErrorMessage = `Failed to compile anonymous template: Unexpected identifier
+
+generated code:
+function(app, bdom, helpers) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0="class">test</div>\`);
+  
+  return function template(ctx, node, key = "") {
+    let attr1 = ctx['a']ctx['b'];
+    return block1([attr1]);
+  }
+}`;
+    const app = new App(Parent as typeof Component);
+    let error: Error;
+    const mountProm = app.mount(fixture).catch((e: Error) => (error = e));
+    await expect(nextAppError(app)).resolves.toThrow(expectedErrorMessage);
+    await mountProm;
+    expect(error!).toBeDefined();
+    expect(error!.message).toBe(expectedErrorMessage);
+  });
+
   test("simple catchError", async () => {
     class Boom extends Component {
       static template = xml`<div t-esc="a.b.c"/>`;

tests/components/style_class.test.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "../../src/runtime/error_handling";
+import { OwlError } from "../../src/common/owl_error";
 import { App, Component, mount, onMounted, useState, xml } from "../../src";
 import { makeTestFixture, nextAppError, nextTick, snapshotEverything } from "../helpers";
 

tests/helpers.ts

@@ -19,7 +19,7 @@ import { helpers } from "../src/runtime/template_helpers";
 import { TemplateSet, globalTemplates } from "../src/runtime/template_set";
 import { BDom } from "../src/runtime/blockdom";
 import { compile } from "../src/compiler";
-import { OwlError } from "../src/runtime/error_handling";
+import { OwlError } from "../src/common/owl_error";
 
 const mount = blockDom.mount;
 

tests/misc/__snapshots__/portal.test.ts.snap

@@ -18,7 +18,7 @@ exports[`Portal Add and remove portals 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['portalIds']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`portalId\`] = v_block1[i1];
+      ctx[\`portalId\`] = k_block1[i1];
       const key1 = ctx['portalId'];
       const ctx1 = capture(ctx);
       c_block1[i1] = withKey(comp1({target: '#outside',slots: {'default': {__render: slot1.bind(this), __ctx: ctx1}}}, key + \`__1__\${key1}\`, node, ctx, Portal), key1);
@@ -47,7 +47,7 @@ exports[`Portal Add and remove portals on div 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['portalIds']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`portalId\`] = v_block1[i1];
+      ctx[\`portalId\`] = k_block1[i1];
       const key1 = ctx['portalId'];
       const ctx1 = capture(ctx);
       c_block1[i1] = withKey(comp1({target: '#outside',slots: {'default': {__render: slot1.bind(this), __ctx: ctx1}}}, key + \`__1__\${key1}\`, node, ctx, Portal), key1);
@@ -77,7 +77,7 @@ exports[`Portal Add and remove portals with t-foreach 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['portalIds']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`portalId\`] = v_block1[i1];
+      ctx[\`portalId\`] = k_block1[i1];
       const key1 = ctx['portalId'];
       let txt1 = ctx['portalId'];
       const ctx1 = capture(ctx);
@@ -109,7 +109,7 @@ exports[`Portal Add and remove portals with t-foreach and destroy 1`] = `
     ctx = Object.create(ctx);
     const [k_block1, v_block1, l_block1, c_block1] = prepareList(ctx['portalIds']);;
     for (let i1 = 0; i1 < l_block1; i1++) {
-      ctx[\`portalId\`] = v_block1[i1];
+      ctx[\`portalId\`] = k_block1[i1];
       const key1 = ctx['portalId'];
       let txt1 = ctx['portalId'];
       const ctx1 = capture(ctx);
@@ -142,7 +142,7 @@ exports[`Portal Add and remove portals with t-foreach inside div 1`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList(ctx['portalIds']);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`portalId\`] = v_block2[i1];
+      ctx[\`portalId\`] = k_block2[i1];
       const key1 = ctx['portalId'];
       let txt1 = ctx['portalId'];
       const ctx1 = capture(ctx);
@@ -429,7 +429,7 @@ exports[`Portal conditional use of Portal with child and div 2`] = `
     ctx = Object.create(ctx);
     const [k_block2, v_block2, l_block2, c_block2] = prepareList([1]);;
     for (let i1 = 0; i1 < l_block2; i1++) {
-      ctx[\`elem\`] = v_block2[i1];
+      ctx[\`elem\`] = k_block2[i1];
       const key1 = ctx['elem'];
       const ctx1 = capture(ctx);
       c_block2[i1] = withKey(comp1({target: '#outside',slots: {'default': {__render: slot1.bind(this), __ctx: ctx1}}}, key + \`__1__\${key1}\`, node, ctx, Portal), key1);
@@ -479,7 +479,7 @@ exports[`Portal conditional use of Portal with child and div, variation 2`] = `
     ctx = Object.create(ctx);
     const [k_block3, v_block3, l_block3, c_block3] = prepareList([1]);;
     for (let i1 = 0; i1 < l_block3; i1++) {
-      ctx[\`elem\`] = v_block3[i1];
+      ctx[\`elem\`] = k_block3[i1];
       const key1 = ctx['elem'];
       const ctx1 = capture(ctx);
       c_block3[i1] = withKey(comp1({target: '#outside',slots: {'default': {__render: slot1.bind(this), __ctx: ctx1}}}, key + \`__1__\${key1}\`, node, ctx, Portal), key1);

tests/misc/portal.test.ts

@@ -1,4 +1,4 @@
-import { OwlError } from "../../src/runtime/error_handling";
+import { OwlError } from "../../src/common/owl_error";
 import {
   App,
   Component,
@@ -988,7 +988,7 @@ describe("Portal: Props validation", () => {
       error = e as Error;
     }
     expect(error!).toBeDefined();
-    expect(error!.message).toBe(`Unexpected token ','`);
+    expect(error!.message).toContain(`Unexpected token ','`);
   });
 
   test("target must be a valid selector", async () => {

tools/devtools/src/devtools_app/store/store.js

@@ -899,7 +899,7 @@ function keepEnvLit(details) {
       alreadyMet.add(details.env.children[i].name);
     } else {
       let lastElement = details.env.children[i];
-      while (lastElement.children.at(-1).name === "[[Prototype]]") {
+      while (lastElement.children.at(-1)?.name === "[[Prototype]]") {
         for (const [index, child] of lastElement.children.entries()) {
           if (index < lastElement.children.length - 1) {
             if (!alreadyMet.has(child.name)) {

tools/release.js

@@ -82,6 +82,12 @@ async function startRelease() {
     return;
   }
 
+  // ---------------------------------------------------------------------------
+  log(`Step ${step++}/${STEPS}: updating package.json...`);
+  await writeFile("package.json", JSON.stringify({...package, version: next}, null, 2) + "\n");
+  await writeFile("package-lock.json", JSON.stringify({...packageLock, version: next}, null, 2) + "\n");
+  await writeFile("./src/version.ts", `// do not modify manually. This file is generated by the release script.\nexport const version = "${next}";\n`);
+
   // ---------------------------------------------------------------------------
   log(`Step ${step++}/${STEPS}: building owl...`);
   await execCommand("rm -rf dist/");
@@ -108,13 +114,6 @@ async function startRelease() {
   await execCommand("cd dist && zip -r owl-devtools.zip devtools-chrome devtools-firefox && cd ..");
   await execCommand("rm -r dist/devtools-chrome dist/devtools-firefox && rm dist/compiler.js");
 
-  // ---------------------------------------------------------------------------
-  log(`Step ${step++}/${STEPS}: updating package.json...`);
-  await writeFile("package.json", JSON.stringify({...package, version: next}, null, 2) + "\n");
-  await writeFile("package-lock.json", JSON.stringify({...packageLock, version: next}, null, 2) + "\n");
-  await writeFile("./src/version.ts", `// do not modify manually. This file is generated by the release script.\nexport const version = "${next}";\n`);
-
-
   // ---------------------------------------------------------------------------
   log(`Step ${step++}/${STEPS}: updating owl on github page...`);
   await fs.copyFileSync("dist/owl.es.js", "docs/owl.js");