[REL] v2.1.1

# v2.1.1

 - [FIX] components: solve missing update (concurrency issue)
 - [DOC] remove old references to comp for useRef hook
 - [FIX] devtools: Fix build commands for windows users
 - [FIX] devtools: Fix devtools in detached window
 - [IMP] devtools: Add a button to navigate to the doc
 - [IMP] devtools: Add devtools documentation
 - [IMP] Allow app to be mounted in shadow DOM
 - [IMP] playground: allow sharing playground links
 - [IMP] runtime: allow validating object values using a type description
 - [FIX] devtools: Increase vertical padding of the search bar
 - [FIX] devtools: Hide the collapse all button
 - [FIX] devtools: Fix bad computation of highlight boxes on the page
 - [FIX] package: Auto-update package-lock.json

.eslintrc

@@ -0,0 +1,47 @@
+{
+    "env": {
+        "browser": true,
+        "node": true,
+        "es2022": true
+    },
+    "parser": "@typescript-eslint/parser",
+    "plugins": ["@typescript-eslint"],
+    "parserOptions": {
+        "sourceType": "module"
+    },
+    "root": true,
+    "rules": {
+        "no-restricted-globals": ["error", "event", "self"],
+        "no-const-assign": ["error"],
+        "no-debugger": ["error"],
+        "no-dupe-class-members": ["error"],
+        "no-dupe-keys": ["error"],
+        "no-dupe-args": ["error"],
+        "no-dupe-else-if": ["error"],
+        "no-unsafe-negation": ["error"],
+        "no-duplicate-imports": ["error"],
+        "valid-typeof": ["error"],
+        "@typescript-eslint/no-unused-vars": ["error", { "vars": "all", "args": "none", "ignoreRestSiblings": false, "caughtErrors": "all" }],
+        "no-restricted-syntax": [
+            "error",
+            {
+                "selector": "MemberExpression[object.name='test'][property.name='only']",
+                "message": "test.only(...) is forbidden",
+            },
+            {
+                "selector": "MemberExpression[object.name='describe'][property.name='only']",
+                "message": "describe.only(...) is forbidden",
+            }
+        ],
+    },
+    "globals": {
+        "describe": true,
+        "expect": true,
+        "test": true,
+        "beforeEach": true,
+        "beforeAll": true,
+        "afterEach": true,
+        "afterAll": true,
+        "jest": true,
+    },
+}

.github/workflows/deploy.yml

@@ -22,7 +22,8 @@ jobs:
       uses: actions/setup-node@v1
       with:
         node-version: ${{ matrix.node-version }}
-    - run: npm install
+    - run: npm ci
     - run: npm run test
     - run: npm run check-formatting
+    - run: npm run lint
     - run: npm run build

.gitignore

@@ -14,9 +14,6 @@ npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
 
-package-lock.json
-yarn.lock
-
 #ide's
 .vscode
 .idea
@@ -31,4 +28,4 @@ release-notes.md
 .rpt2_cache
 
 # useful in some cases
-/temp
+/temp

README.md

@@ -93,6 +93,7 @@ Are you new to Owl? This is the place to start!
 - [Loading Templates](doc/reference/app.md#loading-templates)
 - [Mounting a component](doc/reference/app.md#mount-helper)
 - [Portal](doc/reference/portal.md)
+- [Precompiling templates](doc/reference/precompiling_templates.md)
 - [Props](doc/reference/props.md)
 - [Props Validation](doc/reference/props.md#props-validation)
 - [Reactivity](doc/reference/reactivity.md)
@@ -112,6 +113,7 @@ Are you new to Owl? This is the place to start!
 - [Why did Odoo build Owl?](doc/miscellaneous/why_owl.md)
 - [Changelog (from owl 1.x to 2.x)](CHANGELOG.md)
 - [Notes on compiled templates](doc/miscellaneous/compiled_template.md)
+- [Owl devtools extension](doc/tools/devtools.md)
 
 ## Installing Owl
 
@@ -120,8 +122,28 @@ Owl is available on `npm` and can be installed with the following command:
 ```
 npm install @odoo/owl
 ```
-
 If you want to use a simple `<script>` tag, the last release can be downloaded here:
 
-- [owl-1.4.10](https://github.com/odoo/owl/releases/tag/v1.4.10)
+- [owl](https://github.com/odoo/owl/releases/latest)
+
+## Installing Owl devtools
+
+The Owl devtools browser extension is also available in the [release](https://github.com/odoo/owl/releases/latest):
+Unzip the owl-devtools.zip file and follow the instructions depending on your browser:
+
+### Chrome
+
+Go to your chrome extensions admin panel, activate developer mode and click on `Load unpacked`.
+Select the devtools-chrome folder and that's it, your extension is active! 
+There is a convenient refresh button on the extension card (still on the same admin page) to update your code. 
+Do note that if you got some problems, you may need to completly remove and reload the extension to completly refresh the extension.
+
+### Firefox 
+Go to the address about:debugging#/runtime/this-firefox and click on `Load temporary Add-on...`.
+Select any file in the devtools-firefox folder and that's it, your extension is active! 
+Here, you can use the reload button to refresh the extension.
+
+Note that you may have to open another window or reload your tab to see the extension working.
+Also note that the extension will only be active on pages that have a sufficient version of owl.
+
 

doc/learning/tutorial_todoapp.md

@@ -174,9 +174,9 @@ class Root extends Component {
 ```
 
 The template contains a [`t-foreach`](../reference/templates.md#loops) loop to iterate
-through the tasks. It can find the `tasks` list from the component, since the
-component is the rendering context. Note that we use the `id` of each task as a
-`t-key`, which is very common. There are two css classes: `task-list` and `task`,
+through the tasks. It can find the `tasks` list from the component, since the rendering
+context contains the properties of the component. Note that we use the `id` of each task
+as a `t-key`, which is very common. There are two css classes: `task-list` and `task`,
 that we will use in the next section.
 
 Finally, notice the use of the `t-att-checked` attribute:
@@ -502,6 +502,10 @@ deleteTask(task) {
 Notice that the `onDelete` prop is defined with a `.bind` suffix: this is a special
 suffix that makes sure the function callback is bound to the component.
 
+Notice also that we have two functions named `deleteTask`. The one in the Task
+component just delegates the work to the Root component that owns the task list
+via the `onDelete` property.
+
 ## 10. Using a store
 
 Looking at the code, it is apparent that all the code handling tasks is scattered
@@ -770,10 +774,11 @@ For reference, here is the final code:
     <meta charset="UTF-8" />
     <title>OWL Todo App</title>
     <link rel="stylesheet" href="app.css" />
+  </head>
+  <body>
     <script src="owl.js"></script>
     <script src="app.js"></script>
-  </head>
-  <body></body>
+  </body>
 </html>
 ```
 

doc/readme.md

@@ -45,4 +45,5 @@ Utility/helpers:
 - [`loadFile`](reference/utils.md#loadfile): an helper to load a file from the server
 - [`markup`](reference/templates.md#outputting-data): utility function to define strings that represent html (should not be escaped)
 - [`status`](reference/component.md#status-helper): utility function to get the status of a component (new, mounted or destroyed)
+- [`validate`](reference/utils.md#validate): validates if an object satisfies a specified schema
 - [`whenReady`](reference/utils.md#whenready): utility function to execute code when DOM is ready

doc/reference/app.md

@@ -61,6 +61,8 @@ The `config` object is an object with some of the following keys:
   templates (see [translations](translations.md))
 - **`templates (string | xml document)`**: all the templates that will be used by
   the components created by the application.
+- **`warnIfNoStaticProps (boolean, default=false)`**: if true, Owl will log a warning
+  whenever it encounters a component that does not provide a [static props description](props.md#props-validation).
 
 ## `mount` helper
 

doc/reference/component.md

@@ -76,7 +76,8 @@ The `Component` class has a very small API.
 
   By default, the render initiated by this method will stop at each child
   component if their props are (shallow) equal. To force a render to update
-  all child components, one can use the optional `deep` argument.
+  all child components, one can use the optional `deep` argument. Note that the
+  value of the `deep` argument needs to be a boolean, not a truthy value.
 
 ## Static Properties
 

doc/reference/context.md

@@ -1,105 +0,0 @@
-# 🦉 Context 🦉
-
-## Content
-
-- [Overview](#overview)
-- [Example](#example)
-- [Reference](#reference)
-  - [`Context`](#context)
-  - [`useContext`](#usecontext)
-
-## Overview
-
-The `Context` object provides a way to share data between an arbitrary number
-of components. Usually, data is passed from a parent to its children component,
-but when we have to deal with some mostly global information, this can be
-annoying, since each component will need to pass the information to each children,
-even though some or most of them will not use the information.
-
-With a `Context` object, each component can subscribe (with the `useContext` hook)
-to its state, and will be updated whenever the context state is updated.
-
-## Example
-
-Assume that we have an application with various components which needs to render
-differently depending on the size of the device. Here is how we could proceed
-to make sure that the information is properly shared. First, let us create a
-context, and add it to the environment:
-
-```js
-const deviceContext = new Context({ isMobile: true });
-App.env.deviceContext = deviceContext;
-```
-
-If we want to make it completely responsive, we need to update its value whenever
-the size of the screen is updated:
-
-```js
-const isMobile = () => window.innerWidth <= 768;
-window.addEventListener(
-  "resize",
-  owl.utils.debounce(() => {
-    const state = deviceContext.state;
-    if (state.isMobile !== isMobile()) {
-      state.isMobile = !state.isMobile;
-    }
-  }, 15)
-);
-```
-
-Then, each component that want can subscribe and render differently depending on the
-fact that we are in a mobile or desktop mode.
-
-```js
-class SomeComponent extends Component {
-  static template = xml`
-    <div>
-      <t t-if=device.isMobile>
-          some simplified user interface
-      </t>
-      <t t-else="">
-          a more advanced user interface
-      </t>
-    </div>`;
-  device = useContext(this.env.deviceContext);
-}
-```
-
-## Reference
-
-### `Context`
-
-A `Context` object should be created with a state object:
-
-```js
-const someContext = new Context({ some: "key" });
-```
-
-Its state is now available in the `state` key:
-
-```js
-someContext.state.some = "other key";
-```
-
-This is the way some global code (such as the responsive code above) should
-read and update the context state. However, components should not ever read the
-context state directly from the context, they should instead use the `useContext`
-hook to properly register themselves to state changes.
-
-Note that the `Context` hook is different from the React version. For example,
-there is no concept of provider/consumer. So, the `Context` feature does not
-by itself allow the use of a different context state depending on the component
-place in the component tree. However, this functionality can be obtained, if
-necessary, with the use of sub environment.
-
-### `useContext`
-
-The `useContext` hook is the normal way for a component to register themselve
-to context state changes. The `useContext` method returns the context state:
-
-```js
-device = useContext(this.env.deviceContext);
-```
-
-It is a simple observed state (with an owl `Observer`), which contains the shared
-information.

doc/reference/hooks.md

@@ -112,17 +112,16 @@ of a component, rendered by Owl. It only work on a html element tagged by the
 
 ```xml
 <div>
-    <input t-ref="someDiv"/>
+    <input t-ref="someInput"/>
     <span>hello</span>
 </div>
 ```
 
-In this example, the component will be able to access the `div` and the component
-`SubComponent` with the `useRef` hook:
+In this example, the component will be able to access the `input` with the `useRef` hook:
 
 ```js
 class Parent extends Component {
-  inputRef = useRef("someComponent");
+  inputRef = useRef("someInput");
 
   someMethod() {
     // here, if component is mounted, refs are active:
@@ -139,18 +138,18 @@ The `t-ref` directive also accepts dynamic values with string interpolation
 `t-component` directives). For example,
 
 ```xml
-<div t-ref="component_{{someCondition ? '1' : '2'}}"/>
+<div t-ref="div_{{someCondition ? '1' : '2'}}"/>
 ```
 
 Here, the references need to be set like this:
 
 ```js
-this.ref1 = useRef("component_1");
-this.ref2 = useRef("component_2");
+this.ref1 = useRef("div_1");
+this.ref2 = useRef("div_2");
 ```
 
 References are only guaranteed to be active while the parent component is mounted.
-If this is not the case, accessing `el` or `comp` on it will return `null`.
+If this is not the case, accessing `el` on it will return `null`.
 
 ### `useSubEnv` and `useChildSubEnv`
 
@@ -234,7 +233,8 @@ are defined by a function instead of just the dependencies.
 
 The `useEffect` hook takes two function: the effect function and the dependency
 function. The effect function perform some task and return (optionally) a cleanup
-function. The dependency function returns a list of dependencies. If any of these
+function. The dependency function returns a list of dependencies, these dependencies
+are passed as parameters in the effect function . If any of these
 dependencies changes, then the current effect will be cleaned up and reexecuted.
 
 Here is an example without any dependencies:

doc/reference/precompiling_templates.md

@@ -0,0 +1,30 @@
+# 🦉 Precompiling templates 🦉
+
+Owl is designed to be used by the Odoo javascript framework. Since Odoo handles
+its assets in its own non standard way, it was decided/assumed that Owl would
+compile templates at runtime.
+
+However, in some cases, it is not optimal, or even worse, not possible to do that.
+For example, browser extensions do not allow javascript code to create a new
+function (using the `new Function(...)` syntax).
+
+Therefore, in these cases, it is required to compile templates ahead of time. It
+is possible to do that in Owl, but the tooling is still rough. For now, the
+process is the following:
+
+1. write your templates in xml files (with a `t-name` directive to declare the name
+   of the template)
+2. Compile them in a `templates.js` file
+3. get the `owl.iife.runtime.js` file (which is a owl build without the compiler)
+4. bundle `owl.iife.runtime.js` and `template.js` with your assets (owl needs to
+   be positioned before the templates)
+
+Here is a more detailed explanation on how to compile xml files into a js file:
+
+1. clone the owl repository locally
+2. `npm install` to install all the required tooling
+3. `npm run build:runtime` to build the `owl.iife.runtime.js` file
+4. `npm run build:compiler` to build the template compiler
+5. `npm run compile_templates -- path/to/your/templates` will scan your target
+   folder, find all xml files, get all templates, compile them, and generate a
+   `templates.js` file.

doc/reference/props.md

@@ -4,6 +4,7 @@
 
 - [Overview](#overview)
 - [Definition](#definition)
+- [Props comparison](#props-comparison)
 - [Binding function props](#binding-function-props)
 - [Dynamic Props](#dynamic-props)
 - [Default Props](#default-props)
@@ -56,6 +57,47 @@ the `props` object contains the following keys:
 - for `ComponentA`: `a` and `b`,
 - for `ComponentB`: `model`,
 
+## Props comparison
+
+Whenever Owl encounters a subcomponent in a template, it performs a shallow
+comparison of all props. If they are all referentially equal, then the subcomponent
+will not even be updated. Otherwise, if at least one props has changed, then
+Owl will update it.
+
+However, in some cases, we know that two values are different, but they have the
+same effect, and should not be considered different by Owl. For example, anonymous
+functions in a template are always different, but most of them should not be
+considered different:
+
+```xml
+<t t-foreach="todos" t-as="todo" t-key="todo.id">
+  <Todo todo="todo" onDelete="() => deleteTodo(todo.id)" />
+</t>
+```
+
+In that case, one can use the `.alike` suffix:
+
+```xml
+<t t-foreach="todos" t-as="todo" t-key="todo.id">
+  <Todo todo="todo" onDelete.alike="() => deleteTodo(todo.id)" />
+</t>
+```
+
+This tells Owl that this specific prop should always be considered equivalent
+(or, in other words, should be removed from the list of comparable props).
+
+Note that even if most anonymous functions should probably be considered `alike`,
+it is not necessarily true in all cases. It depends on what values are captured
+by the anonymous function. The following example shows a case where it is probably
+wrong to use `.alike`.
+
+```xml
+<t t-foreach="todos" t-as="todo" t-key="todo.id">
+  <!-- Probably wrong! todo.isCompleted may change -->
+  <Todo todo="todo" toggle.alike="() => toggleTodo(todo.isCompleted)" />
+</t>
+```
+
 ## Binding function props
 
 It is common to have the need to pass a callback as a prop. Since Owl components
@@ -95,6 +137,9 @@ class SomeComponent extends Component {
 }
 ```
 
+The `.bind` suffix also implies `.alike`, so these props will not cause additional
+renderings.
+
 ## Dynamic Props
 
 The `t-props` directive can be used to specify totally dynamic props:
@@ -159,6 +204,7 @@ For each key, a `prop` definition is either a boolean, a constructor, a list of
 - a boolean: indicate that the props exists, and is mandatory.
 - a constructor: this should describe the type, for example: `id: Number` describe
   the props `id` as a number
+- an object describing a value as type. This is done by using the `value` key. For example, `{value: false}` specifies that the corresponding value should be equal to false.
 - a list of constructors. In that case, this means that we allow more than one
   type. For example, `id: [Number, String]` means that `id` can be either a string
   or a number.
@@ -166,6 +212,7 @@ For each key, a `prop` definition is either a boolean, a constructor, a list of
   - `type`: the main type of the prop being validated
   - `element`: if the type was `Array`, then the `element` key describes the type of each element in the array. If it is not set, then we only validate the array, not its elements,
   - `shape`: if the type was `Object`, then the `shape` key describes the interface of the object. If it is not set, then we only validate the object, not its elements,
+  - `values`: if the type was `Object`, then the `values` key describes the interface of values in the object, this allows validating objects that are used as mappings, where keys are not known in advance but the shape of the values is.
   - `validate`: this is a function which should return a boolean to determine if
     the value is valid or not. Useful for custom validation logic.
   - `optional`: if true, the prop is not mandatory
@@ -230,6 +277,10 @@ class ComponentB extends owl.Component {
         name: {type: String, optional: true},
         url: String
       ]},    // object, with keys id (number), name (string, optional) and url (string)
+    someObj3: {
+      type: Object,
+      values: { type: Array, element: String },
+    }, // object with arbitary keys where values are arrays of strings
     someFlag: Boolean,     // a boolean, mandatory (even if `false`)
     someVal: [Boolean, Date],   // either a boolean or a date
     otherValue: true,     // indicates that it is a prop
@@ -240,9 +291,12 @@ class ComponentB extends owl.Component {
     size: {
       validate:  e => ["small", "medium", "large"].includes(e)
     },
+    someId: [Number, {value: false}], // either a number or false
   };
 ```
 
+Note: the props validation code is done by using the [validate utility function](utils.md#validate).
+
 ## Good Practices
 
 A `props` object is a collection of values that come from the parent. As such,

doc/reference/reactivity.md

@@ -2,130 +2,394 @@
 
 ## Content
 
-- [Overview](#overview)
+- [Introduction](#introduction)
 - [`useState`](#usestate)
 - [`reactive`](#reactive)
-- [`markRaw`](#markraw)
-- [`toRaw`](#toraw)
+- [`Escape hatches`](#escape-hatches)
+- [`Advanced usage`](#advanced-usage)
 
-## Overview
+## Introduction
 
 Reactivity is a big topic in javascript frameworks. The goal is to provide a
-simple way to manipulate state, in such a way that the interface automatically
-update accordingly to state changes. Also, we obviously want this to happen in
-a performant way.
+simple way to manipulate state, in such a way that the interface updates automatically
+according to state changes, and to do so in a performant manner.
 
-To solve this issue, Owl provides two reactivity primitives:
-
-- `reactive`, which returns a proxy to its first argument, and tracks all read/update
-  operation going through it,
-- `useState`: a hook, that internally uses `reactive`, and is linked to its
-  owner component: any read operation will be tracked (key by key), and any
-  updates to these tracked values will cause the component to be rerendered.
-
-Most of the time, the `useState` hook is the best solution.
-
-Since version 2.0, Owl applies the fine grained reactivity at the component
-level: props are automatically turned into reactive object, so Owl can track
-which part of these props are consumed by each component, and is therefore able
-to only rerender the impacted components.
+To this end, Owl provides a proxy-based reactivity system, based on the `reactive` primitive.
+The `reactive` function takes an object as a first argument, and an optional callback as its second
+argument, it returns a proxy of the object. This proxy tracks what properties are read
+through the proxy, and calls the provided callback whenever one of these properties is changed
+through any reactive version of the same object. It does so in depth, by returning reactive versions
+of the subobjects when they are read.
 
 ## `useState`
 
-Let us start by an example of how `useState` could be used:
+While the `reactive` primitive is very powerful, its usage in components follow a very standard pattern:
+components want to be rerendered when part of the state which they depend on for rendering changes. To
+this end, owl provides a standard hook: `useState`. To put it simply, this hook simply calls reactive
+with the provided object, and the current component's render function as its callback. This will cause
+it to rerender whenever any part of the state object that has been read by this component is modified.
+
+Here is a simple example of how `useState` can be used:
 
 ```js
 class Counter extends Component {
   static template = xml`
-    <div t-on-click="increment">
+    <div t-on-click="() => this.state.value++">
       <t t-esc="state.value"/>
     </div>`;
 
   setup() {
     this.state = useState({ value: 0 });
   }
+}
+```
 
-  increment() {
-    this.state.value++;
+This component reads `state.value` when it renders, subscribing it to changes to that key. Whenever
+the value changes, Owl will update the component. Note that there is nothing special about the
+`state` property, you can name your state variables whatever you want, and you can have multiple of
+them on the same component if it makes sense to do so. This also allows `useState` to be used in custom
+hooks that may require state that is specific to that hook.
+
+### Reactive props
+
+Since version 2.0, Owl renders are no longer "deep" by default: a component is only rerendered by its
+parent if its props have changed (using a simple equality test). What if the contents of a props have
+changed in a deeper property? If that prop is reactive, owl will rerender the child components that
+need to be updated automatically, and only those components, it does so by reobserving reactive
+objects passed as props to components. Consider the following example:
+
+```js
+class Counter extends Component {
+  static template = xml`
+    <div t-on-click="() => props.state.value++">
+      <t t-esc="props.state.value"/>
+    </div>`;
+}
+
+class Parent extends Component {
+  static template = xml`
+    <Counter state="this.state"/>
+    <button t-on-click="() => this.state.value = 0">Reset counter</button>
+    <button t-on-click="() => this.state.test++" t-esc="this.state.test"/>`;
+
+  setup() {
+    this.state = useState({ value: 0, test: 1 });
   }
 }
 ```
 
-If one were to use a simple state object, Owl would not be aware that the value
-was changed and that the component should be rerendered. With the `useState`
-hook, `this.state` is now a reactive object, so this component works as expected.
+When clicking on the counter button, only the Counter rerenders, because the Parent has never read
+the "value" key in the state. When clicking on the "Reset Counter" button, the same thing happens:
+only the Counter component rerenders. What matters is not _where_ the state is updated, but which
+parts of the state are updated, and which components depend on them. This is achieved by Owl by
+automatically calling `useState` on reactive objects passed as props to a child component.
+
+When clicking on the last button, the parent is rerendered, but the child does not care about the
+`test` key: it has not read it. The props that we give it (`this.state`) have also not changed,
+as such, the parent updates but the child doesn't.
+
+For most day-to-day operations, `useState` should cover all of your needs. If
+you are curious about more advanced use cases and technical details, read on.
+
+### Debugging subscriptions
+
+Owl provides a way to show which reactive objects and keys a component is subscribed to: you can
+look at `component.__owl__.subscriptions`. Note that this is on the internal `__owl__` field, and
+should not be used in any type of production code as the name of this property or any of its properties
+or methods are subject to change at any point, even in stable versions of Owl, and may become available
+only in debug mode in the future.
 
 ## `reactive`
 
 The `reactive` function is the basic reactivity primitive. It takes an object
 or an array as first argument, and optionally, a function as the second argument.
-The function will be called whenever any tracked value is updated.
+The function is called whenever any tracked value is updated.
 
 ```js
 const obj = reactive({ a: 1 }, () => console.log("changed"));
 
-obj.a = 2; // does not log anything: the 'a' key was not read
-console.log(obj.a); // log 2, and reads the 'a' key => it is now tracked
-obj.a = 3; // log 'changed' because we updated a tracked value
+obj.a = 2; // does not log anything: the 'a' key has not been read yet
+console.log(obj.a); // logs 2 and reads the 'a' key => it is now tracked
+obj.a = 3; // logs 'changed' because we updated a tracked value
 ```
 
 An important property of reactive objects is that they can be reobserved: this
-will create an independant proxy that tracks another set of keys:
+will create an independent proxy that tracks another set of keys:
 
 ```js
 const obj1 = reactive({ a: 1, b: 2 }, () => console.log("observer 1"));
 const obj2 = reactive(obj1, () => console.log("observer 2"));
 
-console.log(obj1.a); // log 1, and reads the 'a' key => it is now tracked by observer 1
-console.log(obj1.b); // log 2, and 'b' is now tracked by observer 1
-console.log(obj2.b); // log 2, and 'b' is now tracked by observer 1
-obj2.a = 3; // log 'observer1', because observer2 does not track a
-obj2.b = 3; // log 'observer1' and 'observer2'
+console.log(obj1.a); // logs 1, and reads the 'a' key => it is now tracked by observer 1
+console.log(obj2.b); // logs 2, and 'b' is now tracked by observer 2
+obj2.a = 3; // only logs 'observer1', because observer2 does not track a
+obj2.b = 3; // only logs 'observer2', because observer1 does not track b
+console.log(obj2.a, obj1.b); // logs 3 and 3, while the object is observed independently, it is still a single object
 ```
 
-Obviously, one can use `reactive` on the result of a `useState` if wanted, this
-is the proper way to watch for some state changes.
+Because `useState` returns a normal reactive object, it is possible to call `reactive` on the result
+of a `useState` to observe changes to that object while outside the context of a component, or to
+call `useState` on reactive objects created outside of components. In those cases, one needs to be
+careful with regards to the lifetime of those reactive objects, as holding references to these
+objects may prevent garbage collection of the component and its data even if Owl has destroyed it.
 
-## `markRaw`
+### Subscriptions are ephemereal
 
-Marks an object so that it is ignored by the reactivity system. This function returns its argument.
+Subscription to state changes are ephemereal, whenever an observer is notified that a state object
+has changed, all of its subscriptions are cleared, meaning that if it still cares about it, it
+should read the properties it cares about again. For example:
 
 ```js
-const someObject = markRaw(...);
+const obj = reactive({ a: 1 }, () => console.log("observer called"));
+
+console.log(obj.a); // logs 1, and reads the 'a' key => it is now tracked by the observer
+obj.a = 3; // logs 'observer1' and clears the subscriptions of the observer
+obj.a = 4; // doesn't log anything, the key is no longer observed
+```
+
+This may seem counter-intuitive, but it makes perfect sense in the context of components:
+
+```js
+class DoubleCounter extends Component {
+  static template = xml`
+    <t t-esc="state.selected + ': ' + state[state.selected].value"/>
+    <button t-on-click="() => this.state.count1++">increment count 1</button>
+    <button t-on-click="() => this.state.count2++">increment count 2</button>
+    <button t-on-click="changeCounter">Switch counter</button>
+  `;
+
+  setup() {
+    this.state = useState({ selected: "count1", count1: 0, count2: 0 });
+  }
+
+  changeCounter() {
+    this.state.selected = this.state.selected === "count1" ? "count2" : "count1";
+  }
+}
+```
+
+In this component, if we increment the value of the second counter, the component will not rerender,
+which makes sense as rerendering will have no effect, as the second counter is not displayed. If we
+toggle the component to display the second counter, we now no longer want the component to rerender
+when the value of the first counter changes, and this is what happens: a component only rerenders
+when there are changes to pieces of state that have been read during or after the previous render.
+If a piece of state has not been read in the last render, we know that its value won't influence the
+rendered output, and so we can ignore it.
+
+### reactive `Map` and `Set`
+
+The reactivity system has special support built-in for the standard container types `Map` and `Set`.
+They behave like one would expect: reading a key subscribes the observer to that key, adding or
+removing an item to them notifies observers that have used any of the iterators on that reactive
+object, such as `.entries()` or `.keys()`, likewise with clearing them.
+
+## Escape hatches
+
+Sometimes, it is desirable to bypass the reactivity system. Creating proxies when interacting with
+reactive objects is expensive, and while on the whole, the performance benefit that we get by
+rerendering only the parts of the interface that need it outweighs that cost, in some cases, we want
+to be able to opt out of creating them in the first place. This is the purpose of `markRaw`:
+
+### `markRaw`
+
+Marks an object so that it is ignored by the reactivity system, meaning that if this object is ever
+part of a of a reactive object, it will be returned as is, and no keys in that object will be
+observed.
+
+```js
+const someObject = markRaw({ b: 1 });
 const state = useState({
   a: 1,
-  obj: someObject
+  obj: someObject,
 });
-// here, state.obj === someObject
+console.log(state.obj.b); // attempt to subscribe to the "b" key in someObject
+state.obj.b = 2; // No rerender will occur here
+console.log(someObject === state.obj); // true
 ```
 
-This is useful in some rare cases. For example, some complex and large object such
-that going through the reactivity system may cause a non trivial performance slowdown.
+This is useful in some rare cases. One such example would be if you want to use an array of objects
+that is potentially large to render a list, but those objects are known to be immutable:
+
+```js
+this.items = useState([
+  { label: "some text", value: 42 },
+  // ... 1000 total objects
+]);
+```
+
+in the template:
+
+```xml
+<t t-foreach="items" t-as="item" t-key="item.label" t-esc="item.label + item.value"/>
+```
+
+Here, on every render, we go and read one thousand keys from a reactive object, which causes
+one thousand reactive objects to be created. If we know that the content of these objects
+cannot change, this is wasted work. If instead all of these objects are marked as raw, we avoid
+all of this work while keeping the ability to lean on the reactivity to track the presence and
+identity of these objects:
+
+```js
+this.items = useState([
+  markRaw({ label: "some text", value: 42 }),
+  // ... 1000 total objects
+]);
+```
 
 However, use this function with caution: this is an escape hatch from the reactivity
-system, and as such, using it may cause subtle and unintended issues!
-
-## `toRaw`
-
-Given a reactive object, this function returns the underlying, non-reactive,
-corresponding object.
+system, and as such, using it may cause subtle and unintended issues! For example:
 
 ```js
-// in setup
-const state = useState({ value: 1 });
+// This will cause a rerender
+this.items.push(markRaw({ label: "another label", value: 1337 }));
 
-// later:
-const rawState = toRaw(this.state);
-rawState.value = 3; // will NOT be picked up by the reactivity system!!!
+// THIS WILL NOT CAUSE A RENDER!
+this.items[17].value = 3;
+// The UI is now desynced from component's state until the next render caused by something else
 ```
 
-Here again, this is useful in some situations where we want to explicitely bypass
-Owl, but using this function means that the responsability of coordinating
-state update is given to the user code, instead of Owl. Subtle bugs may arise!
+In short: only use `markRaw` if your application is slowing down noticeably and profiling reveals
+that a lot of time is spent creating useless reactive objects.
 
-Also, normal (non-reactive objects) will be directly returned by `toRaw`:
+### `toRaw`
+
+While `markRaw` marks an object so that it is never made reactive, `toRaw` takes an object and
+returns the underlying non-reactive object. It can be useful in some niche cases. In particular,
+because the reactivity system returns a proxy, the returned object does not compare equal to the
+original object:
 
 ```js
-const obj = { a: 1 };
-console.log(toRaw(obj) === obj); // true
+const obj = {};
+const reactiveObj = reactive(obj);
+console.log(obj === reactiveObj); // false
+console.log(obj === toRaw(reactiveObj)); // true
 ```
+
+It can also be useful during debugging, as unfolding proxies recursively in debuggers can be confusing.
+
+## Advanced usage
+
+The following is a collection of small snippets that leverage the reactivity system in
+"non-standard" ways to help you understand its power and where using it might make your code simpler.
+
+### Notification manager
+
+Showing notifications is a pretty common need in web applications, you may want to show a
+notification from any other component within the application, and the notifications should stack on
+top of one another regardless of which component spawned them, here is how we can leverage the
+reactivity to accomplish this:
+
+```js
+let notificationId = 1;
+const notifications = reactive({});
+class NotificationContainer extends Component {
+  static template = xml`
+    <t t-foreach="notifications" t-as="notification" t-key="notification_key" t-esc="notification"/>
+  `;
+  setup() {
+    this.notifications = useState(notifications);
+  }
+}
+
+export function addNotification(label) {
+  const id = notificationId++;
+  notifications[id] = label;
+  return () => {
+    delete notifications[id];
+  };
+}
+```
+
+Here, the `notifications` variable is a reactive object. Notice how we didn't give `reactive` a
+callback: this is because in this case, all we care about is that adding or removing notifications
+in the `addNotification` function goes through the reactivity system. The `NotificationContainer`
+component reobserves this object with `useState`, and is updated whenever notifications are
+added or removed.
+
+### Store
+
+Centralizing application state is a pretty common want/need in web applications. Because of the way
+the reactivity system works, you can treat any reactive object as a store, and if you call `useState`
+on it, components automatically observe only the part of the store that they're interested in:
+
+```js
+export const store = reactive({
+  list: [],
+  add(item) {
+    this.list.push(item);
+  },
+});
+
+export function useStore() {
+  return useState(store);
+}
+```
+
+In any component:
+
+```js
+import { useStore } from "./store";
+
+class List extends Component {
+  static template = xml`
+    <t t-foreach="store.list" t-as="item" t-key="item" t-esc="item"/>
+  `;
+  setup() {
+    this.store = useStore();
+  }
+}
+```
+
+Anywhere in the application:
+
+```js
+import { store } from "./store";
+// Will cause any instance of the List component in the app to update
+store.add("New list item!");
+```
+
+Notice how we can make objects with methods into reactive objects, and when these methods are used
+to mutate the store contents, it works as expected. And while stores are generally one-off objects,
+it is entirely possible to make class instances reactive:
+
+```js
+class Store {
+  list = [];
+  add(item) {
+    this.list.push(item);
+  }
+}
+// Essentially equivalent to the previous code
+export const store = reactive(new Store());
+```
+
+Which can be useful to unit test the class separately.
+
+### Local storage synchronization
+
+Sometimes, you want to persist some state accross reloads, you can do this by storing it in the
+`localStorage`, but what if you want to update the `localStorage` item every time the state changes,
+so that you don't have to manually synchronize the states? Well, you can use the reactivity system
+to write a custom hook that will do that for you:
+
+```js
+function useStoredState(key, initialState) {
+  const state = JSON.parse(localStorage.getItem(key)) || initialState;
+  const store = (obj) => localStorage.setItem(key, JSON.stringify(obj));
+  const reactiveState = reactive(state, () => store(reactiveState));
+  store(reactiveState);
+  return useState(state);
+}
+
+class MyComponent extends Component {
+  setup() {
+    this.state = useStoredState("MyComponent.state", { value: 1 });
+  }
+}
+```
+
+One important thing to notice is that both times we call `store`, we call it with `reactiveState`,
+not `state`: we need `store` to read the keys through a reactive object for it to correctly
+subscribe to state changes. Notice also that we call `store` the first time by hand, as otherwise it
+will not be subscribed to anything, and no amount of change in the object will cause the reactive
+callback to be invoked.

doc/reference/slots.md

@@ -239,6 +239,12 @@ And the child component that includes the slot can provide values like this:
 <t t-slot="foo" bool="other_var" num="5">
 ```
 
+or this:
+
+```xml
+<t t-slot="foo" t-props="someObject">
+```
+
 In the case of the default slot, you may declare the slot scope directly on the
 component itself:
 

doc/reference/templates.md

@@ -115,7 +115,7 @@ It is useful to explain the various rules that apply on these expressions:
    <div><p t-if="console.log(1)">NOT valid</p></div>
    ```
 
-2. it can use anything in the rendering context (typically, the component):
+2. it can use anything in the rendering context (which typically contains the properties of the component):
 
    ```xml
    <p t-if="user.birthday === today()">Happy bithday!</p>
@@ -290,10 +290,11 @@ If an expression evaluates to a falsy value, it will not be set at all:
 
 It is sometimes convenient to format an attribute with string interpolation. In
 that case, the `t-attf-` directive can be used. It is useful when we need to mix
-literal and dynamic elements, such as css classes.
+literal and dynamic elements, such as css classes. The dynamic elements can be
+specified with either `{{...}}` or `#{...}`:
 
 ```xml
-<div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>
+<div t-attf-foo="a {{value1}} is #{value2} of {{value3}} ]"/>
 <!-- result if values are set to 1,2 and 3: <div foo="a 0 is 1 of 2 ]"></div> -->
 ```
 
@@ -476,7 +477,7 @@ not work with other iterables, such as `Set`. However, it is only a matter of
 using the `...` javascript operator. For example:
 
 ```xml
-<t t-foreach="...items" t-as="item">...</t>
+<t t-foreach="[...items]" t-as="item">...</t>
 ```
 
 The `...` operator will convert the `Set` (or any other iterables) into a list,
@@ -539,6 +540,14 @@ This can be used to define variables scoped to a sub template:
 <!-- "var" does not exist here -->
 ```
 
+Note: by default, the rendering context for a sub template is simply the current
+rendering context. However, it may be useful to be able to specify a specific
+object as context. This can be done by using the `t-call-context` directive:
+
+```xml
+<t t-call="other-template" t-call-context="obj"/>
+```
+
 ### Dynamic sub templates
 
 The `t-call` directive can also be used to dynamically call a sub template,

doc/reference/utils.md

@@ -8,6 +8,7 @@ functions are all available in the `owl.utils` namespace.
 - [`whenReady`](#whenready): executing code when DOM is ready
 - [`loadFile`](#loadfile): loading a file (useful for templates)
 - [`EventBus`](#eventbus): a simple EventBus
+- [`validate`](#validate): a validation function
 
 ## `whenReady`
 
@@ -56,3 +57,24 @@ bus.addEventListener("event", () => console.log("something happened"));
 
 bus.trigger("event"); // 'something happened' is logged
 ```
+
+## `validate`
+
+The `validate` function is a function that validates if a given object satisfies a
+specified schema. It is actually used by Owl itself to perform
+[props validation](props.md#props-validation). For example:
+
+```js
+validate(
+  { a: "hey" },
+  {
+    id: Number,
+    url: [Boolean, { type: Array, element: Number }],
+  }
+);
+
+// throws an error with the following information:
+//    - unknown key 'a',
+//    - 'id' is missing (should be a number),
+//    - 'url' is missing (should be a boolean or list of numbers),
+```

doc/tools/devtools.md

@@ -0,0 +1,56 @@
+# Owl Devtools Browser extension
+
+The owl devtools browser extension is an extension available on chrome or firefox which adds an owl tab
+to the browser devtools in order to inspect all owl apps that are present on any web page, their components
+and allows to interract with their data to a certain extend. There is also a profiler available to visualize
+the components' lifecycle and be able to trace their origin.
+
+See the [`devtools doc`](devtools_guide.md) for more information.
+
+## Install the extension manually (for devs)
+
+In the owl root folder:
+
+```bash
+npm install
+```
+
+For chrome:
+
+```bash
+npm run build:devtools-chrome
+```
+
+For firefox:
+
+```bash
+npm run build:devtools-firefox
+```
+
+You can also run:
+
+```bash
+npm run dev:devtools-chrome
+```
+
+or
+
+```bash
+npm run dev:devtools-firefox
+```
+
+to avoid recompiling owl and gain time if it has already been done.
+
+To run the extension:
+
+In google chrome: go to your chrome extensions admin panel, activate developer mode and click on `Load unpacked`.
+Select the output folder (dist/devtools) and that's it, your extension is active!
+There is a convenient refresh button on the extension card (still on the same admin page) to update your code.
+Do note that if you got some problems, you may need to completly remove and reload the extension to completly refresh the extension.
+
+In firefox: go to the address about:debugging#/runtime/this-firefox and click on `Load temporary Add-on...`.
+Select any file of the output folder (dist/devtools) and that's it, your extension is active!
+Here, you can use the reload button to refresh the extension.
+
+Note that you may have to open another window or reload your tab to see the extension working.
+Also note that the extension will only be active on pages that have a sufficient version of owl.

doc/tools/devtools_guide.md

@@ -0,0 +1,150 @@
+# Owl Devtools Guide
+
+## Information popup
+
+After having installed the extension, a new icon will be added to your extension bar.
+If you don't see it, you can pin the extension using the extensions popup.
+
+<img src="screenshots/extensions.png"/>
+
+Clicking on the owl icon will open the information popup. This popup is useful
+to know in advance whether owl is loaded in the tab or not. This is also indicated
+by the icon itself: if it is flipped upside-down, it means that owl is not loaded in the
+active tab. Do note that old versions of owl are not supported by the extension and will
+therefore be indicated either as obsolete or absent by the extension popup.
+
+<img src="screenshots/popup.png"/>
+
+## First steps
+
+When you are on a page where owl is detected, you can open your devtools either with
+right-click -> Inspect or using F12. In the devtools menu, you can search for the Owl
+tab which is added by the extension. It will be present by default at the end of the list but
+you can drag and drop it at the position you want for easier navigation in the future.
+
+<img src="screenshots/find_owl_tab.png"/>
+
+When you open the tab, you arrive on the Components view by default which is one of the
+two available tabs at the top. Here is an example of the devtools on the Odoo CRM app:
+
+<img src="screenshots/crm.png"/>
+
+## Components tab
+
+The components tab is separated into two sub windows: the components tree in the left and
+the component details in the right. The components tree will display all the different
+components that are present in the tab in the form of a tree. The root of this tree is
+actually the app which is not a component but can still be inspected by the devtools like
+one. There can also be multiple apps loaded in the page like in the following:
+
+<img src="screenshots/multi_apps.png"/>
+
+There is a convenient search bar at the top of the components tree which will help finding
+the components tou want in the tree and also, an element picker can be used to directly select
+the component you want to focus on in the page which is especially useful when trying to find
+what you want. Just click on the elements picker icon and click on the element you want to focus
+on in the page and it will be selected in the devtools accordingly. Hovering any element in the
+page in this mode will highlight it and the same happens anytime in the components tree.
+
+<img src="screenshots/picker.png"/>
+
+In the tree itself, the navigation is quite simple and is similar to the one in the Elements tab
+of the browser's devtools. It is possible to navigate with the keyboard using the arrow keys and
+multiple shortcuts are available in a custom menu when right-clicking on a component. This menu
+allows to expand/fold all the children nodes of a component, fold its direct children only, inspect
+the source code of the component, send it as a global variable in the console, go to the Elements tab
+and focus on its content, force a rerender of the component, send its observed states to the console
+as a global variable, inspect its compiled template in the Sources tab or send its raw template
+to the console.
+
+<img src="screenshots/menu.png"/>
+
+The component details window in the right will show the component that is currently selected as well
+as its env, props, observed states and all the other variables that are present on its instance.
+While the props and the env are already present on the actual instance of the component and are
+pretty explicit by themselves, the observed state value is a bit more complicated to grasp.
+
+The observed state is actually information about which variables are observed by the component
+which will trigger a rerender of the component when it is modified. The keys represent which part of the
+variable is actually observed and the target is the actual variable. For simplicity, the properties
+that are not observed by the component are greyed out while the others are in bold. This means that
+editing bold ones will trigger a rerender while the greyed out ones will not.
+
+<img src="screenshots/states.png"/>
+
+In the given example, we have two keys/target pairs for two different variables. The first one indicates
+that adding or removing an element to the array will trigger a rerender since the length will have changed.
+Replacing the element at index 0, 1 or 2 will also have the same effect as implied by the keys. It doesn't
+mean that editing the properties of element at index 0, 1 or 2 will rerender the component though. It may
+be the case for some but this will be described in another keys/target pair. The second keys/target pair
+is actually the element at index 0 of the first pair. It only has id in the keys meaning that only the
+id property will actually trigger a rerender the component when modified. Be aware however that the other
+properties may be in the observed state of another component like a child one in this case. A greyed out
+property only implies it is not reactive for the selected component and not for the others.
+
+The navigation inside the properties is also similar to the one in console variables: properties have
+their prototype displayed and getters will get their value when clicked on (...). It is also possible to
+send any property to the console using the right-click context menu on it and functions can be inspected
+in the sources tab as well.
+
+<img src="screenshots/function_menu.png"/>
+
+There are several icons available to perform several of the actions described before in the components
+tree context menu and all these actions are also available by opening the menu by right-clicking on the
+component's name. Using the left click on the component's name will focus it in the components tree.
+
+It is also possible to edit any of the leaf node properties. To do so, you must double click on the
+property's value and modify it using the freshly created input then press enter to apply the changes.
+Do note that the modified values should be written in JSON format in order to be valid (examples:
+89, "yes", undefined, null, \["hello", 15\], {"a": 1}, true, ...). Whether it has an impact on the
+component or not and whether it produces an error is the responsability of the user.
+
+<img src="screenshots/edit.png"/>
+
+## Profiler
+
+The profiler tab is the other tab of the owl devtools. It consists in an actions bar at the top and
+a tree/list of events related to the owl components' renders. Here is an example of the events launched
+when entering the Odoo Crm app.
+
+<img src="screenshots/profiler.png"/>
+
+In the initial state, no event is displayed. You need to activate the recording of events before they
+are intercepted by the devtools using the record button.
+
+<img src="screenshots/record.png"/>
+
+The second button is used to clear all the events that have been recorded. The select can be used to
+switch between the tree view (which shows the causality between renders) and the events log view which
+simply displays the events in the exact order they were triggered. In this view, you can expand the create,
+update and destroy events which reveals the component that initiated the event.
+
+<img src="screenshots/events_log.png"/>
+
+The third button is only visible in tree view and allows to fold all the render events that were recorded.
+Some actions are also available when using the right-click on any event of the tree view for navigation
+purpose in a similar fashion as in the components tree.
+
+<img src="screenshots/tree_actions.png"/>
+
+There is also the Trace Renderings and Trace Subscriptions features. These features are independant of the
+recording of events and have no effect on the profiler tab. The Trace Renderings option is used to log in
+the console all the render events and allows to show their traceback information. Similarly, the Trace
+Subscriptions option logs all the properties that caused a render event and also allows to see the traceback
+of the modification
+
+<img src="screenshots/trace_rendering.png"/>
+<img src="screenshots/trace_subscriptions.png"/>
+
+## Options
+
+The owl devtools extension has a dark mode feature which defaults to your general devtools settings and can
+be toggled using the sun/moon icon at the top-right corner of the tab. All the examples above were created
+with the dark mode enabled. There is also a refresh button to completely reset the owl devtools.
+
+<img src="screenshots/darkmode.png"/>
+
+## Troubleshooting
+
+If the feedback from the page to the devtools seems to be cut, just close the devtools and refresh the page.
+This will eventually happen any time a tab stays opened for too long without being refreshed.

package.json

@@ -1,11 +1,10 @@
 {
   "name": "@odoo/owl",
-  "version": "2.0.0-beta-5",
+  "version": "2.1.1",
   "description": "Odoo Web Library (OWL)",
   "main": "dist/owl.cjs.js",
-  "browser": "dist/owl.iife.js",
   "module": "dist/owl.es.js",
-  "types": "dist/types/index.d.ts",
+  "types": "dist/types/owl.d.ts",
   "files": [
     "dist"
   ],
@@ -14,7 +13,14 @@
   },
   "scripts": {
     "build:bundle": "rollup -c --failAfterWarnings",
+    "build:runtime": "rollup -c --failAfterWarnings runtime",
+    "build:compiler": "rollup -c --failAfterWarnings compiler",
     "build": "npm run build:bundle",
+    "build:devtools": "rollup -c ./tools/devtools/rollup.config.js",
+    "dev:devtools-chrome": "npm run build:devtools -- --config-browser=chrome",
+    "dev:devtools-firefox": "npm run build:devtools -- --config-browser=firefox",
+    "build:devtools-chrome": "npm run dev:devtools-chrome -- --config-env=production",
+    "build:devtools-firefox": "npm run dev:devtools-firefox -- --config-env=production",
     "test": "jest",
     "test:debug": "node --inspect-brk node_modules/.bin/jest --runInBand --watch --testTimeout=5000000",
     "test:watch": "jest --watch",
@@ -22,10 +28,12 @@
     "playground": "npm run build && npm run playground:serve",
     "preplayground:watch": "npm run build",
     "playground:watch": "npm-run-all  --parallel playground:serve \"build:* -- --watch\"",
-    "prettier": "prettier {src/*.ts,src/**/*.ts,tests/*.ts,tests/**/*.ts,doc/*.md,doc/**/*.md} --write",
-    "check-formatting": "prettier {src/*.ts,src/**/*.ts,tests/*.ts,tests/**/*.ts,doc/*.md,doc/**/*.md} --check",
+    "prettier": "prettier {src/*.ts,src/**/*.ts,tests/*.ts,tests/**/*.ts,doc/*.md,doc/**/*.md,tools/devtools/**/*.js} --write",
+    "check-formatting": "prettier {src/*.ts,src/**/*.ts,tests/*.ts,tests/**/*.ts,doc/*.md,doc/**/*.md,tools/devtools/**/*.js} --check",
+    "lint": "eslint src/**/*.ts tests/**/*.ts",
     "publish": "npm run build && npm publish",
-    "release": "node tools/release.js"
+    "release": "node tools/release.js",
+    "compile_templates": "node tools/compile_xml.js"
   },
   "repository": {
     "type": "git",
@@ -40,25 +48,29 @@
   "devDependencies": {
     "@types/jest": "^27.0.1",
     "@types/node": "^14.11.8",
+    "@typescript-eslint/eslint-plugin": "5.48.1",
+    "@typescript-eslint/parser": "5.48.1",
     "chalk": "^3.0.0",
-    "cpx": "^1.5.0",
     "current-git-branch": "^1.1.0",
-    "git-rev-sync": "^1.12.0",
+    "eslint": "8.31.0",
+    "git-rev-sync": "^3.0.2",
     "github-api": "^3.3.0",
     "jest": "^27.1.0",
     "jest-diff": "^27.3.1",
     "jest-environment-jsdom": "^27.1.0",
-    "live-server": "^1.2.1",
     "npm-run-all": "^4.1.5",
     "prettier": "2.4.1",
     "rollup": "^2.56.3",
+    "rollup-plugin-copy": "^3.3.0",
+    "rollup-plugin-delete": "^2.0.0",
+    "rollup-plugin-dts": "^4.2.2",
+    "rollup-plugin-execute": "^1.1.1",
+    "rollup-plugin-string": "^3.0.0",
     "rollup-plugin-terser": "^7.0.2",
     "rollup-plugin-typescript2": "^0.31.1",
-    "sass": "^1.16.1",
     "source-map-support": "^0.5.10",
     "ts-jest": "^27.0.5",
-    "typescript": "4.5.2",
-    "uglify-es": "^3.3.9"
+    "typescript": "4.5.2"
   },
   "jest": {
     "testEnvironment": "jsdom",

roadmap.md

@@ -1,28 +1,9 @@
 # 🦉 OWL Roadmap 🦉
 
-- Current version: 1.4.10
+- Current version: 2.X
 - Status: stable
 
-This roadmap is only an attempt at predicting Owl's future.  Everything may
-change!
-
-
-### 1.x
-
-- add chrome and firefox devtools,
-- fix every bugs,
-- improve documentation,
-- small backward compatible improvements.
-
-### 2.x (2020? 2021? 2022?)
-
-- stop support for `t-set` directive to define the content of a slot
-
-Maybe:
-
-- reimplement vdom to use *block* system, like Vue 3, which should make Owl
-  much faster
-- refactor `QWeb` to use an intermediate representation (some kind of AST) to
-  allow additional optimisations.
-
+Owl is currently stable. No (large) improvements is expected in the near future.
 
+Note that we intend to keep maintaining owl, and as such, improvements and/or
+breaking changes may require a version bump in the future.

rollup.config.js

@@ -2,28 +2,57 @@ import pkg from "./package.json";
 import git from "git-rev-sync";
 import typescript from 'rollup-plugin-typescript2';
 import { terser } from "rollup-plugin-terser";
+import dts from "rollup-plugin-dts";
 
-const name = "owl";
-const extend = true;
+let input, output;
+
+const IIFE_FILENAME = "dist/owl.iife.js";
+const CJS_FILENAME = "dist/owl.cjs.js";
+const ES_FILENAME = "dist/owl.es.js";
+
+if (pkg.module !== ES_FILENAME || pkg.main !== CJS_FILENAME) {
+  throw new Error("package.json has been modified. Build script should be updated accordingly");
+}  
 
-/**
- * Meta data to be added on the __info__ object.
- * Used to let external tools know the current owl version.
- */
 const outro = `
-__info__.version = '${pkg.version}';
 __info__.date = '${new Date().toISOString()}';
 __info__.hash = '${git.short()}';
 __info__.url = 'https://github.com/odoo/owl';
 `;
 
+switch (process.argv[4]) {
+  case "compiler": 
+    input = "src/compiler/index.ts",
+    output = [
+      getConfigForFormat('cjs', 'dist/compiler.js', ''),
+    ]
+    break;
+  case "runtime":
+    input = "src/runtime/index.ts";
+    output = [
+      getConfigForFormat('esm', addSuffix(ES_FILENAME,  'runtime'), outro),
+      getConfigForFormat('cjs', addSuffix(CJS_FILENAME,  'runtime'), outro),
+      getConfigForFormat('iife', addSuffix(IIFE_FILENAME,  'runtime'), outro),
+      getConfigForFormat('iife', addSuffix(IIFE_FILENAME,  'runtime'), outro, true),
+    ]
+    break;
+  default:
+    input = "src/index.ts",
+    output = [
+      getConfigForFormat('esm', ES_FILENAME, outro),
+      getConfigForFormat('cjs', CJS_FILENAME, outro),
+      getConfigForFormat('iife', IIFE_FILENAME, outro),
+      getConfigForFormat('iife', IIFE_FILENAME, outro, true),
+    ]
+  }
+
 /**
  * Generate from a string depicting a path a new path for the minified version.
  * @param {string} pkgFileName file name
  */
-function generateMinifiedNameFromPkgName(pkgFileName) {
+function addSuffix(pkgFileName, suffix) {
   const parts = pkgFileName.split('.');
-  parts.splice(parts.length - 1, 0, "min");
+  parts.splice(parts.length - 1, 0, suffix);
   return parts.join('.');
 }
 
@@ -33,12 +62,12 @@ function generateMinifiedNameFromPkgName(pkgFileName) {
  * @param {string} generatedFileName generated file name
  * @param {boolean} minified should it be minified
  */
-function getConfigForFormat(format, generatedFileName, minified = false) {
+function getConfigForFormat(format, generatedFileName, outro, minified = false) {
   return {
-    file: minified ? generateMinifiedNameFromPkgName(generatedFileName) : generatedFileName,
+    file: minified ? addSuffix(generatedFileName, "min") : generatedFileName,
     format: format,
-    name: name,
-    extend: extend,
+    name: "owl",
+    extend: true,
     outro: outro,
     freeze: false,
     plugins: minified ? [terser()] : [],
@@ -46,26 +75,19 @@ function getConfigForFormat(format, generatedFileName, minified = false) {
   };
 }
 
-export default {
-  input: "src/index.ts",
-  output: [
-
-    /**
-     * Read about module formats:
-     *  https://auth0.com/blog/javascript-module-systems-showdown/
-     *  https://medium.com/@kelin2025/so-you-wanna-use-es6-modules-714f48b3a953
-     */
-
-    getConfigForFormat('esm', pkg.module),
-    getConfigForFormat('esm', pkg.module, true),
-    getConfigForFormat('cjs', pkg.main),
-    getConfigForFormat('cjs', pkg.main, true),
-    getConfigForFormat('iife', pkg.browser),
-    getConfigForFormat('iife', pkg.browser, true),
-  ],
-  plugins: [
-    typescript({
-      useTsconfigDeclarationDir: true
-    }),
-  ]
-};
+export default [
+  {
+    input,
+    output,
+    plugins: [
+      typescript({
+        useTsconfigDeclarationDir: true
+      }),
+    ]
+  },
+  {
+    input: "dist/types/index.d.ts",
+    output: [{ file: "dist/types/owl.d.ts", format: "es" }],
+    plugins: [dts()],
+  },
+];

src/app/app.ts

@@ -1,120 +0,0 @@
-import { Component, ComponentConstructor } from "../component/component";
-import { ComponentNode } from "../component/component_node";
-import { MountOptions } from "../component/fibers";
-import { Scheduler } from "../component/scheduler";
-import { TemplateSet, TemplateSetConfig } from "./template_set";
-import { nodeErrorHandlers } from "../component/error_handling";
-import { validateTarget } from "../utils";
-
-// reimplement dev mode stuff see last change in 0f7a8289a6fb8387c3c1af41c6664b2a8448758f
-
-export interface Env {
-  [key: string]: any;
-}
-
-export interface AppConfig<P, E> extends TemplateSetConfig {
-  props?: P;
-  env?: E;
-  test?: boolean;
-}
-
-let hasBeenLogged = false;
-
-export const DEV_MSG = () => {
-  const hash = (window as any).owl ? (window as any).owl.__info__.hash : "master";
-
-  return `Owl is running in 'dev' mode.
-
-This is not suitable for production use.
-See https://github.com/odoo/owl/blob/${hash}/doc/reference/app.md#configuration for more information.`;
-};
-
-export class App<
-  T extends abstract new (...args: any) => any = any,
-  P extends object = any,
-  E = any
-> extends TemplateSet {
-  static validateTarget = validateTarget;
-
-  Root: ComponentConstructor<P, E>;
-  props: P;
-  env: E;
-  scheduler = new Scheduler();
-  root: ComponentNode<P, E> | null = null;
-
-  constructor(Root: ComponentConstructor<P, E>, config: AppConfig<P, E> = {}) {
-    super(config);
-    this.Root = Root;
-    if (config.test) {
-      this.dev = true;
-    }
-    if (this.dev && !config.test && !hasBeenLogged) {
-      console.info(DEV_MSG());
-      hasBeenLogged = true;
-    }
-    const env = config.env || {};
-    const descrs = Object.getOwnPropertyDescriptors(env);
-    this.env = Object.freeze(Object.create(Object.getPrototypeOf(env), descrs));
-    this.props = config.props || ({} as P);
-  }
-
-  mount(target: HTMLElement, options?: MountOptions): Promise<Component<P, E> & InstanceType<T>> {
-    App.validateTarget(target);
-    const node = this.makeNode(this.Root, this.props);
-    const prom = this.mountNode(node, target, options);
-    this.root = node;
-    return prom;
-  }
-
-  makeNode(Component: ComponentConstructor, props: any): ComponentNode {
-    return new ComponentNode(Component, props, this, null, null);
-  }
-
-  mountNode(node: ComponentNode, target: HTMLElement, options?: MountOptions) {
-    const promise: any = new Promise((resolve, reject) => {
-      let isResolved = false;
-      // manually set a onMounted callback.
-      // that way, we are independant from the current node.
-      node.mounted.push(() => {
-        resolve(node.component);
-        isResolved = true;
-      });
-
-      // Manually add the last resort error handler on the node
-      let handlers = nodeErrorHandlers.get(node);
-      if (!handlers) {
-        handlers = [];
-        nodeErrorHandlers.set(node, handlers);
-      }
-      handlers.unshift((e) => {
-        if (isResolved) {
-          console.error(e);
-        } else {
-          reject(e);
-        }
-        throw e;
-      });
-    });
-    node.mountComponent(target, options);
-    return promise;
-  }
-
-  destroy() {
-    if (this.root) {
-      this.scheduler.flush();
-      this.root.destroy();
-    }
-  }
-}
-
-export async function mount<
-  T extends abstract new (...args: any) => any = any,
-  P extends object = any,
-  E = any
->(
-  C: T & ComponentConstructor<P, E>,
-  target: HTMLElement,
-  config: AppConfig<P, E> & MountOptions = {}
-): Promise<Component<P, E> & InstanceType<T>> {
-  return new App(C, config).mount(target, config);
-}

src/app/template_helpers.ts

@@ -1,203 +0,0 @@
-import { BDom, multi, text, toggler, createCatcher } from "../blockdom";
-import { validateProps } from "../component/props_validation";
-import { Markup } from "../utils";
-import { html } from "../blockdom/index";
-import { TARGET } from "../reactivity";
-
-/**
- * This file contains utility functions that will be injected in each template,
- * to perform various useful tasks in the compiled code.
- */
-
-function withDefault(value: any, defaultValue: any): any {
-  return value === undefined || value === null || value === false ? defaultValue : value;
-}
-
-function callSlot(
-  ctx: any,
-  parent: any,
-  key: string,
-  name: string,
-  dynamic: boolean,
-  extra: any,
-  defaultContent?: (ctx: any, node: any, key: string) => BDom
-): BDom {
-  key = key + "__slot_" + name;
-  const slots = ctx.props[TARGET].slots || {};
-  const { __render, __ctx, __scope } = slots[name] || {};
-  const slotScope = Object.create(__ctx || {});
-  if (__scope) {
-    slotScope[__scope] = extra;
-  }
-  const slotBDom = __render ? __render.call(__ctx.__owl__.component, slotScope, parent, key) : null;
-  if (defaultContent) {
-    let child1: BDom | undefined = undefined;
-    let child2: BDom | undefined = undefined;
-    if (slotBDom) {
-      child1 = dynamic ? toggler(name, slotBDom) : slotBDom;
-    } else {
-      child2 = defaultContent.call(ctx.__owl__.component, ctx, parent, key);
-    }
-    return multi([child1, child2]);
-  }
-  return slotBDom || text("");
-}
-
-function capture(ctx: any): any {
-  const component = ctx.__owl__.component;
-  const result = Object.create(component);
-  for (let k in ctx) {
-    result[k] = ctx[k];
-  }
-  return result;
-}
-
-function withKey(elem: any, k: string) {
-  elem.key = k;
-  return elem;
-}
-
-function prepareList(collection: any): [any[], any[], number, any[]] {
-  let keys: any[];
-  let values: any[];
-
-  if (Array.isArray(collection)) {
-    keys = collection;
-    values = collection;
-  } else if (collection) {
-    values = Object.keys(collection);
-    keys = Object.values(collection);
-  } else {
-    throw new Error("Invalid loop expression");
-  }
-  const n = values.length;
-  return [keys, values, n, new Array(n)];
-}
-
-const isBoundary = Symbol("isBoundary");
-
-function setContextValue(ctx: { [key: string]: any }, key: string, value: any): void {
-  const ctx0 = ctx;
-  while (!ctx.hasOwnProperty(key) && !ctx.hasOwnProperty(isBoundary)) {
-    const newCtx = ctx.__proto__;
-    if (!newCtx) {
-      ctx = ctx0;
-      break;
-    }
-    ctx = newCtx;
-  }
-  ctx[key] = value;
-}
-
-function toNumber(val: string): number | string {
-  const n = parseFloat(val);
-  return isNaN(n) ? val : n;
-}
-
-function shallowEqual(l1: any[], l2: any[]): boolean {
-  for (let i = 0, l = l1.length; i < l; i++) {
-    if (l1[i] !== l2[i]) {
-      return false;
-    }
-  }
-  return true;
-}
-
-class LazyValue {
-  fn: any;
-  ctx: any;
-  node: any;
-  constructor(fn: any, ctx: any, node: any) {
-    this.fn = fn;
-    this.ctx = capture(ctx);
-    this.node = node;
-  }
-
-  evaluate(): any {
-    return this.fn(this.ctx, this.node);
-  }
-
-  toString() {
-    return this.evaluate().toString();
-  }
-}
-
-/*
- * Safely outputs `value` as a block depending on the nature of `value`
- */
-export function safeOutput(value: any): ReturnType<typeof toggler> {
-  if (!value) {
-    return value;
-  }
-  let safeKey;
-  let block;
-  if (value instanceof Markup) {
-    safeKey = `string_safe`;
-    block = html(value as string);
-  } else if (value instanceof LazyValue) {
-    safeKey = `lazy_value`;
-    block = value.evaluate();
-  } else if (value instanceof String || typeof value === "string") {
-    safeKey = "string_unsafe";
-    block = text(value);
-  } else {
-    // Assuming it is a block
-    safeKey = "block_safe";
-    block = value;
-  }
-  return toggler(safeKey, block);
-}
-
-let boundFunctions = new WeakMap();
-
-function bind(ctx: any, fn: Function): Function {
-  let component = ctx.__owl__.component;
-  let boundFnMap = boundFunctions.get(component);
-  if (!boundFnMap) {
-    boundFnMap = new WeakMap();
-    boundFunctions.set(component, boundFnMap);
-  }
-  let boundFn = boundFnMap.get(fn);
-  if (!boundFn) {
-    boundFn = fn.bind(component);
-    boundFnMap.set(fn, boundFn);
-  }
-  return boundFn;
-}
-
-type RefMap = { [key: string]: HTMLElement | null };
-type RefSetter = (el: HTMLElement | null) => void;
-
-function multiRefSetter(refs: RefMap, name: string): RefSetter {
-  let count = 0;
-  return (el) => {
-    if (el) {
-      count++;
-      if (count > 1) {
-        throw new Error("Cannot have 2 elements with same ref name at the same time");
-      }
-    }
-    if (count === 0 || el) {
-      refs[name] = el;
-    }
-  };
-}
-
-export const helpers = {
-  withDefault,
-  zero: Symbol("zero"),
-  isBoundary,
-  callSlot,
-  capture,
-  withKey,
-  prepareList,
-  setContextValue,
-  multiRefSetter,
-  shallowEqual,
-  toNumber,
-  validateProps,
-  LazyValue,
-  safeOutput,
-  bind,
-  createCatcher,
-};

src/blockdom/event_catcher.ts

@@ -1,89 +0,0 @@
-import { createEventHandler } from "./events";
-import type { VNode } from "./index";
-
-type EventsSpec = { [name: string]: number };
-
-type Catcher = (child: VNode, handlers: any[]) => VNode;
-
-export function createCatcher(eventsSpec: EventsSpec): Catcher {
-  let setupFns: any[] = [];
-  let removeFns: any[] = [];
-  for (let name in eventsSpec) {
-    let index = eventsSpec[name];
-    let { setup, remove } = createEventHandler(name);
-    setupFns[index] = setup;
-    removeFns[index] = remove;
-  }
-  let n = setupFns.length;
-
-  class VCatcher {
-    child: VNode;
-    handlers: any[];
-
-    parentEl?: HTMLElement | undefined;
-    afterNode: Node | null = null;
-
-    constructor(child: VNode, handlers: any[]) {
-      this.child = child;
-      this.handlers = handlers;
-    }
-
-    mount(parent: HTMLElement, afterNode: Node | null) {
-      this.parentEl = parent;
-      this.afterNode = afterNode;
-      this.child.mount(parent, afterNode);
-      for (let i = 0; i < n; i++) {
-        let origFn = this.handlers[i][0];
-        const self = this;
-        this.handlers[i][0] = function (ev: any) {
-          const target = ev.target;
-          let currentNode: any = self.child.firstNode();
-          const afterNode = self.afterNode;
-          while (currentNode !== afterNode) {
-            if (currentNode.contains(target)) {
-              return origFn.call(this, ev);
-            }
-            currentNode = currentNode.nextSibling;
-          }
-        };
-        setupFns[i].call(parent, this.handlers[i]);
-      }
-    }
-
-    moveBefore(other: VCatcher | null, afterNode: Node | null) {
-      this.afterNode = null;
-      this.child.moveBefore(other ? other.child : null, afterNode);
-    }
-
-    patch(other: VCatcher, withBeforeRemove: boolean) {
-      if (this === other) {
-        return;
-      }
-      this.handlers = other.handlers;
-      this.child.patch(other.child, withBeforeRemove);
-    }
-
-    beforeRemove() {
-      this.child.beforeRemove();
-    }
-
-    remove() {
-      for (let i = 0; i < n; i++) {
-        removeFns[i].call(this.parentEl!);
-      }
-      this.child.remove();
-    }
-
-    firstNode(): Node | undefined {
-      return this.child.firstNode();
-    }
-
-    toString(): string {
-      return this.child.toString();
-    }
-  }
-
-  return function (child: VNode, handlers: any[]): VNode<VCatcher> {
-    return new VCatcher(child, handlers);
-  };
-}

src/compiler/index.ts

@@ -1,10 +1,11 @@
-import type { BDom } from "../blockdom";
+import type { TemplateSet } from "../runtime/template_set";
+import type { BDom } from "../runtime/blockdom";
 import { CodeGenerator, Config } from "./code_generator";
 import { parse } from "./parser";
 
 export type Template = (context: any, vnode: any, key?: string) => BDom;
 
-export type TemplateFunction = (blocks: any, utils: any) => Template;
+export type TemplateFunction = (app: TemplateSet, bdom: any, helpers: any) => Template;
 
 interface CompileOptions extends Config {
   name?: string;
@@ -26,5 +27,5 @@ export function compile(
   const codeGenerator = new CodeGenerator(ast, { ...options, hasSafeContext });
   const code = codeGenerator.generateCode();
   // template function
-  return new Function("bdom, helpers", code) as TemplateFunction;
+  return new Function("app, bdom, helpers", code) as TemplateFunction;
 }

src/compiler/inline_expressions.ts

@@ -1,3 +1,5 @@
+import { OwlError } from "../runtime/error_handling";
+
 /**
  * Owl QWeb Expression Parser
  *
@@ -26,7 +28,7 @@
 //------------------------------------------------------------------------------
 
 const RESERVED_WORDS =
-  "true,false,NaN,null,undefined,debugger,console,window,in,instanceof,new,function,return,this,eval,void,Math,RegExp,Array,Object,Date".split(
+  "true,false,NaN,null,undefined,debugger,console,window,in,instanceof,new,function,return,eval,void,Math,RegExp,Array,Object,Date".split(
     ","
   );
 
@@ -85,8 +87,9 @@ const STATIC_TOKEN_MAP: { [key: string]: TKind } = Object.assign(Object.create(n
 });
 
 // note that the space after typeof is relevant. It makes sure that the formatted
-// expression has a space after typeof
-const OPERATORS = "...,.,===,==,+,!==,!=,!,||,&&,>=,>,<=,<,?,-,*,/,%,typeof ,=>,=,;,in ".split(",");
+// expression has a space after typeof. Currently we don't support delete and void
+const OPERATORS =
+  "...,.,===,==,+,!==,!=,!,||,&&,>=,>,<=,<,?,-,*,/,%,typeof ,=>,=,;,in ,new ,|,&,^,~".split(",");
 
 type Tokenizer = (expr: string) => Token | false;
 
@@ -105,14 +108,14 @@ let tokenizeString: Tokenizer = function (expr) {
       i++;
       cur = expr[i];
       if (!cur) {
-        throw new Error("Invalid expression");
+        throw new OwlError("Invalid expression");
       }
       s += cur;
     }
     i++;
   }
   if (expr[i] !== start) {
-    throw new Error("Invalid expression");
+    throw new OwlError("Invalid expression");
   }
   s += start;
   if (start === "`") {
@@ -222,7 +225,7 @@ export function tokenize(expr: string): Token[] {
     error = e; // Silence all errors and throw a generic error below
   }
   if (current.length || error) {
-    throw new Error(`Tokenizer error: could not tokenize \`${expr}\``);
+    throw new OwlError(`Tokenizer error: could not tokenize \`${expr}\``);
   }
   return result;
 }
@@ -344,21 +347,29 @@ export function compileExprToArray(expr: string): Token[] {
   return tokens;
 }
 
+// Leading spaces are trimmed during tokenization, so they need to be added back for some values
+const paddedValues = new Map([["in ", " in "]]);
+
 export function compileExpr(expr: string): string {
   return compileExprToArray(expr)
-    .map((t) => t.value)
+    .map((t) => paddedValues.get(t.value) || t.value)
     .join("");
 }
 
-export const INTERP_REGEXP = /\{\{.*?\}\}/g;
-const INTERP_GROUP_REGEXP = /\{\{.*?\}\}/g;
+export const INTERP_REGEXP = /\{\{.*?\}\}|\#\{.*?\}/g;
 
-export function interpolate(s: string): string {
+export function replaceDynamicParts(s: string, replacer: (s: string) => string) {
   let matches = s.match(INTERP_REGEXP);
   if (matches && matches[0].length === s.length) {
-    return `(${compileExpr(s.slice(2, -2))})`;
+    return `(${replacer(s.slice(2, matches[0][0] === "{" ? -2 : -1))})`;
   }
 
-  let r = s.replace(INTERP_GROUP_REGEXP, (s) => "${" + compileExpr(s.slice(2, -2)) + "}");
+  let r = s.replace(
+    INTERP_REGEXP,
+    (s) => "${" + replacer(s.slice(2, s[0] === "{" ? -2 : -1)) + "}"
+  );
   return "`" + r + "`";
 }
+export function interpolate(s: string): string {
+  return replaceDynamicParts(s, compileExpr);
+}

src/compiler/parser.ts

@@ -1,3 +1,5 @@
+import { OwlError } from "../runtime/error_handling";
+
 // -----------------------------------------------------------------------------
 // AST Type definition
 // -----------------------------------------------------------------------------
@@ -115,6 +117,7 @@ export interface ASTTCall {
   type: ASTType.TCall;
   name: string;
   body: AST[] | null;
+  context: string | null;
 }
 
 interface SlotDefinition {
@@ -258,16 +261,12 @@ function parseTNode(node: Element, ctx: ParsingContext): AST | null {
 // Text and Comment Nodes
 // -----------------------------------------------------------------------------
 const lineBreakRE = /[\r\n]/;
-const whitespaceRE = /\s+/g;
 
 function parseTextCommentNode(node: Node, ctx: ParsingContext): AST | null {
   if (node.nodeType === Node.TEXT_NODE) {
     let value = node.textContent || "";
-    if (!ctx.inPreTag) {
-      if (lineBreakRE.test(value) && !value.trim()) {
-        return null;
-      }
-      value = value.replace(whitespaceRE, " ");
+    if (!ctx.inPreTag && lineBreakRE.test(value) && !value.trim()) {
+      return null;
     }
 
     return { type: ASTType.Text, value };
@@ -318,7 +317,7 @@ function parseDOMNode(node: Element, ctx: ParsingContext): AST | null {
     return null;
   }
   if (tagName.startsWith("block-")) {
-    throw new Error(`Invalid tag name: '${tagName}'`);
+    throw new OwlError(`Invalid tag name: '${tagName}'`);
   }
   ctx = Object.assign({}, ctx);
   if (tagName === "pre") {
@@ -339,13 +338,15 @@ function parseDOMNode(node: Element, ctx: ParsingContext): AST | null {
     const value = node.getAttribute(attr)!;
     if (attr.startsWith("t-on")) {
       if (attr === "t-on") {
-        throw new Error("Missing event name with t-on directive");
+        throw new OwlError("Missing event name with t-on directive");
       }
       on = on || {};
       on[attr.slice(5)] = value;
     } else if (attr.startsWith("t-model")) {
       if (!["input", "select", "textarea"].includes(tagName)) {
-        throw new Error("The t-model directive only works with <input>, <textarea> and <select>");
+        throw new OwlError(
+          "The t-model directive only works with <input>, <textarea> and <select>"
+        );
       }
 
       let baseExpr, expr;
@@ -358,7 +359,7 @@ function parseDOMNode(node: Element, ctx: ParsingContext): AST | null {
         baseExpr = value.slice(0, index);
         expr = value.slice(index + 1, -1);
       } else {
-        throw new Error(`Invalid t-model expression: "${value}" (it should be assignable)`);
+        throw new OwlError(`Invalid t-model expression: "${value}" (it should be assignable)`);
       }
 
       const typeAttr = node.getAttribute("type");
@@ -389,10 +390,10 @@ function parseDOMNode(node: Element, ctx: ParsingContext): AST | null {
         ctx.tModelInfo = model;
       }
     } else if (attr.startsWith("block-")) {
-      throw new Error(`Invalid attribute: '${attr}'`);
+      throw new OwlError(`Invalid attribute: '${attr}'`);
     } else if (attr !== "t-name") {
       if (attr.startsWith("t-") && !attr.startsWith("t-att")) {
-        throw new Error(`Unknown QWeb directive: '${attr}'`);
+        throw new OwlError(`Unknown QWeb directive: '${attr}'`);
       }
       const tModel = ctx.tModelInfo;
       if (tModel && ["t-att-value", "t-attf-value"].includes(attr)) {
@@ -446,7 +447,7 @@ function parseTEscNode(node: Element, ctx: ParsingContext): AST | null {
     };
   }
   if (ast.type === ASTType.TComponent) {
-    throw new Error("t-esc is not supported on Component nodes");
+    throw new OwlError("t-esc is not supported on Component nodes");
   }
   return tesc;
 }
@@ -502,7 +503,7 @@ function parseTForEach(node: Element, ctx: ParsingContext): AST | null {
   node.removeAttribute("t-as");
   const key = node.getAttribute("t-key");
   if (!key) {
-    throw new Error(
+    throw new OwlError(
       `"Directive t-foreach should always be used with a t-key!" (expression: t-foreach="${collection}" t-as="${elem}")`
     );
   }
@@ -557,11 +558,13 @@ function parseTCall(node: Element, ctx: ParsingContext): AST | null {
     return null;
   }
   const subTemplate = node.getAttribute("t-call")!;
-
+  const context = node.getAttribute("t-call-context");
   node.removeAttribute("t-call");
+  node.removeAttribute("t-call-context");
+
   if (node.tagName !== "t") {
     const ast = parseNode(node, ctx);
-    const tcall: AST = { type: ASTType.TCall, name: subTemplate, body: null };
+    const tcall: AST = { type: ASTType.TCall, name: subTemplate, body: null, context };
     if (ast && ast.type === ASTType.DomNode) {
       ast.content = [tcall];
       return ast;
@@ -579,6 +582,7 @@ function parseTCall(node: Element, ctx: ParsingContext): AST | null {
     type: ASTType.TCall,
     name: subTemplate,
     body: body.length ? body : null,
+    context,
   };
 }
 
@@ -682,7 +686,9 @@ function parseComponent(node: Element, ctx: ParsingContext): AST | null {
   let isDynamic = node.hasAttribute("t-component");
 
   if (isDynamic && name !== "t") {
-    throw new Error(`Directive 't-component' can only be used on <t> nodes (used on a <${name}>)`);
+    throw new OwlError(
+      `Directive 't-component' can only be used on <t> nodes (used on a <${name}>)`
+    );
   }
 
   if (!(firstLetter === firstLetter.toUpperCase() || isDynamic)) {
@@ -709,7 +715,7 @@ function parseComponent(node: Element, ctx: ParsingContext): AST | null {
         on[name.slice(5)] = value;
       } else {
         const message = directiveErrorMap.get(name.split("-").slice(0, 2).join("-"));
-        throw new Error(message || `unsupported directive on Component: ${name}`);
+        throw new OwlError(message || `unsupported directive on Component: ${name}`);
       }
     } else {
       props = props || {};
@@ -725,7 +731,7 @@ function parseComponent(node: Element, ctx: ParsingContext): AST | null {
     const slotNodes = Array.from(clone.querySelectorAll("[t-set-slot]"));
     for (let slotNode of slotNodes) {
       if (slotNode.tagName !== "t") {
-        throw new Error(
+        throw new OwlError(
           `Directive 't-set-slot' can only be used on <t> nodes (used on a <${slotNode.tagName}>)`
         );
       }
@@ -771,8 +777,9 @@ function parseComponent(node: Element, ctx: ParsingContext): AST | null {
 
     // default slot
     const defaultContent = parseChildNodes(clone, ctx);
-    if (defaultContent) {
-      slots = slots || {};
+    slots = slots || {};
+    // t-set-slot="default" has priority over content
+    if (defaultContent && !slots.default) {
       slots.default = { content: defaultContent, on, attrs: null, scope: defaultSlotScope };
     }
   }
@@ -900,7 +907,7 @@ function normalizeTIf(el: Element) {
     let nattr = (name: string) => +!!node.getAttribute(name);
     if (prevElem && (pattr("t-if") || pattr("t-elif"))) {
       if (pattr("t-foreach")) {
-        throw new Error(
+        throw new OwlError(
           "t-if cannot stay at the same level as t-foreach when using t-elif or t-else"
         );
       }
@@ -909,19 +916,19 @@ function normalizeTIf(el: Element) {
           return a + b;
         }) > 1
       ) {
-        throw new Error("Only one conditional branching directive is allowed per node");
+        throw new OwlError("Only one conditional branching directive is allowed per node");
       }
       // All text (with only spaces) and comment nodes (nodeType 8) between
       // branch nodes are removed
       let textNode;
       while ((textNode = node.previousSibling) !== prevElem) {
         if (textNode!.nodeValue!.trim().length && textNode!.nodeType !== 8) {
-          throw new Error("text is not allowed between branching directives");
+          throw new OwlError("text is not allowed between branching directives");
         }
         textNode!.remove();
       }
     } else {
-      throw new Error(
+      throw new OwlError(
         "t-elif and t-else directives must be preceded by a t-if or t-elif directive"
       );
     }
@@ -942,7 +949,7 @@ function normalizeTEsc(el: Element) {
   );
   for (const el of elements) {
     if (el.childNodes.length) {
-      throw new Error("Cannot have t-esc on a component that already has content");
+      throw new OwlError("Cannot have t-esc on a component that already has content");
     }
     const value = el.getAttribute("t-esc");
     el.removeAttribute("t-esc");
@@ -996,7 +1003,7 @@ function parseXML(xml: string): XMLDocument {
         }
       }
     }
-    throw new Error(msg);
+    throw new OwlError(msg);
   }
 
   return doc;

src/component/props_validation.ts

@@ -1,150 +0,0 @@
-import { ComponentConstructor } from "./component";
-
-/**
- * Apply default props (only top level).
- *
- * Note that this method does modify in place the props
- */
-export function applyDefaultProps<P>(props: P, ComponentClass: ComponentConstructor<P>) {
-  const defaultProps = ComponentClass.defaultProps;
-  if (defaultProps) {
-    for (let propName in defaultProps) {
-      if ((props as any)[propName] === undefined) {
-        (props as any)[propName] = defaultProps[propName];
-      }
-    }
-  }
-}
-
-//------------------------------------------------------------------------------
-// Prop validation helper
-//------------------------------------------------------------------------------
-function getPropDescription(staticProps: any) {
-  if (staticProps instanceof Array) {
-    return Object.fromEntries(
-      staticProps.map((p) => (p.endsWith("?") ? [p.slice(0, -1), false] : [p, true]))
-    );
-  }
-  return staticProps || { "*": true };
-}
-
-/**
- * Validate the component props (or next props) against the (static) props
- * description.  This is potentially an expensive operation: it may needs to
- * visit recursively the props and all the children to check if they are valid.
- * This is why it is only done in 'dev' mode.
- */
-export function validateProps<P>(name: string | ComponentConstructor<P>, props: P, parent?: any) {
-  const ComponentClass =
-    typeof name !== "string"
-      ? name
-      : (parent.constructor.components[name] as ComponentConstructor<P> | undefined);
-
-  if (!ComponentClass) {
-    // this is an error, wrong component. We silently return here instead so the
-    // error is triggered by the usual path ('component' function)
-    return;
-  }
-  applyDefaultProps(props, ComponentClass);
-
-  const defaultProps = ComponentClass.defaultProps || {};
-  let propsDef = getPropDescription(ComponentClass.props);
-  const allowAdditionalProps = "*" in propsDef;
-
-  for (let propName in propsDef) {
-    if (propName === "*") {
-      continue;
-    }
-    const propDef = propsDef[propName];
-    let isMandatory = !!propDef;
-    if (typeof propDef === "object" && "optional" in propDef) {
-      isMandatory = !propDef.optional;
-    }
-    if (isMandatory && propName in defaultProps) {
-      throw new Error(
-        `A default value cannot be defined for a mandatory prop (name: '${propName}', component: ${ComponentClass.name})`
-      );
-    }
-    if ((props as any)[propName] === undefined) {
-      if (isMandatory) {
-        throw new Error(`Missing props '${propName}' (component '${ComponentClass.name}')`);
-      } else {
-        continue;
-      }
-    }
-    let isValid;
-    try {
-      isValid = isValidProp((props as any)[propName], propDef);
-    } catch (e) {
-      (e as Error).message = `Invalid prop '${propName}' in component ${ComponentClass.name} (${
-        (e as Error).message
-      })`;
-      throw e;
-    }
-    if (!isValid) {
-      throw new Error(`Invalid Prop '${propName}' in component '${ComponentClass.name}'`);
-    }
-  }
-  if (!allowAdditionalProps) {
-    for (let propName in props) {
-      if (!(propName in propsDef)) {
-        throw new Error(`Unknown prop '${propName}' given to component '${ComponentClass.name}'`);
-      }
-    }
-  }
-}
-
-/**
- * Check if an invidual prop value matches its (static) prop definition
- */
-function isValidProp(prop: any, propDef: any): boolean {
-  if (propDef === true) {
-    return true;
-  }
-  if (typeof propDef === "function") {
-    // Check if a value is constructed by some Constructor.  Note that there is a
-    // slight abuse of language: we want to consider primitive values as well.
-    //
-    // So, even though 1 is not an instance of Number, we want to consider that
-    // it is valid.
-    if (typeof prop === "object") {
-      return prop instanceof propDef;
-    }
-    return typeof prop === propDef.name.toLowerCase();
-  } else if (propDef instanceof Array) {
-    // If this code is executed, this means that we want to check if a prop
-    // matches at least one of its descriptor.
-    let result = false;
-    for (let i = 0, iLen = propDef.length; i < iLen; i++) {
-      result = result || isValidProp(prop, propDef[i]);
-    }
-    return result;
-  }
-  // propsDef is an object
-  if (propDef.optional && prop === undefined) {
-    return true;
-  }
-  let result = propDef.type ? isValidProp(prop, propDef.type) : true;
-  if (propDef.validate) {
-    result = result && propDef.validate(prop);
-  }
-  if (propDef.type === Array && propDef.element) {
-    for (let i = 0, iLen = prop.length; i < iLen; i++) {
-      result = result && isValidProp(prop[i], propDef.element);
-    }
-  }
-  if (propDef.type === Object && propDef.shape) {
-    const shape = propDef.shape;
-    for (let key in shape) {
-      result = result && isValidProp(prop[key], shape[key]);
-    }
-    if (result) {
-      for (let propName in prop) {
-        if (!(propName in shape)) {
-          throw new Error(`unknown prop '${propName}'`);
-        }
-      }
-    }
-  }
-  return result;
-}

src/index.ts

@@ -1,56 +1,16 @@
-import {
-  config,
-  createBlock,
-  html,
-  list,
-  mount as blockMount,
-  multi,
-  patch,
-  remove,
-  text,
-  toggler,
-  comment,
-} from "./blockdom";
-import { mainEventHandler } from "./component/handler";
-export type { Reactive } from "./reactivity";
+import { TemplateSet } from "./runtime/template_set";
+import { compile } from "./compiler";
 
-config.shouldNormalizeDom = false;
-config.mainEventHandler = mainEventHandler;
+export * from "./runtime";
 
-export const blockDom = {
-  config,
-  // bdom entry points
-  mount: blockMount,
-  patch,
-  remove,
-  // bdom block types
-  list,
-  multi,
-  text,
-  toggler,
-  createBlock,
-  html,
-  comment,
+TemplateSet.prototype._compileTemplate = function _compileTemplate(
+  name: string,
+  template: string | Element
+) {
+  return compile(template, {
+    name,
+    dev: this.dev,
+    translateFn: this.translateFn,
+    translatableAttributes: this.translatableAttributes,
+  });
 };
-
-export { App, mount } from "./app/app";
-export { Component } from "./component/component";
-export { useComponent, useState } from "./component/component_node";
-export { status } from "./component/status";
-export { reactive, markRaw, toRaw } from "./reactivity";
-export { useEffect, useEnv, useExternalListener, useRef, useChildSubEnv, useSubEnv } from "./hooks";
-export { EventBus, whenReady, loadFile, markup, xml } from "./utils";
-export {
-  onWillStart,
-  onMounted,
-  onWillUnmount,
-  onWillUpdateProps,
-  onWillPatch,
-  onPatched,
-  onWillRender,
-  onRendered,
-  onWillDestroy,
-  onError,
-} from "./component/lifecycle_hooks";
-
-export const __info__ = {};

src/portal.ts

@@ -1,75 +0,0 @@
-import { onWillUnmount } from "./component/lifecycle_hooks";
-import { xml } from "./utils";
-import { BDom, text, VNode } from "./blockdom";
-import { Component } from "./component/component";
-
-const VText: any = text("").constructor;
-
-class VPortal extends VText implements Partial<VNode<VPortal>> {
-  //   selector: string;
-  realBDom: BDom | null;
-  target: HTMLElement | null = null;
-
-  constructor(selector: string, realBDom: BDom) {
-    super("");
-    this.selector = selector;
-    this.realBDom = realBDom;
-  }
-  mount(parent: HTMLElement, anchor: ChildNode) {
-    super.mount(parent, anchor);
-    this.target = document.querySelector(this.selector) as any;
-    if (!this.target) {
-      let el: any = this.el;
-      while (el && el.parentElement instanceof HTMLElement) {
-        el = el.parentElement;
-      }
-      this.target = el && el.querySelector(this.selector);
-      if (!this.target) {
-        throw new Error("invalid portal target");
-      }
-    }
-    this.realBDom!.mount(this.target!, null);
-  }
-
-  beforeRemove() {
-    this.realBDom!.beforeRemove();
-  }
-  remove() {
-    if (this.realBDom) {
-      super.remove();
-      this.realBDom!.remove();
-      this.realBDom = null;
-    }
-  }
-
-  patch(other: VPortal) {
-    super.patch(other);
-    if (this.realBDom) {
-      this.realBDom.patch(other.realBDom!, true);
-    } else {
-      this.realBDom = other.realBDom;
-      this.realBDom!.mount(this.target!, null);
-    }
-  }
-}
-
-export class Portal extends Component {
-  static template = xml`<t t-slot="default"/>`;
-  static props = {
-    target: {
-      type: String,
-    },
-    slots: true,
-  };
-
-  setup() {
-    const node = this.__owl__;
-    const renderFn = node.renderFn;
-    node.renderFn = () => new VPortal(this.props.target, renderFn());
-    onWillUnmount(() => {
-      if (node.bdom) {
-        node.bdom.remove();
-      }
-    });
-  }
-}

src/runtime/app.ts

@@ -0,0 +1,231 @@
+import { version } from "../version";
+import { Component, ComponentConstructor, Props } from "./component";
+import { ComponentNode } from "./component_node";
+import { nodeErrorHandlers, OwlError, handleError } from "./error_handling";
+import { Fiber, RootFiber, MountOptions } from "./fibers";
+import { Scheduler } from "./scheduler";
+import { validateProps } from "./template_helpers";
+import { TemplateSet, TemplateSetConfig } from "./template_set";
+import { validateTarget } from "./utils";
+
+// reimplement dev mode stuff see last change in 0f7a8289a6fb8387c3c1af41c6664b2a8448758f
+
+export interface Env {
+  [key: string]: any;
+}
+
+export interface AppConfig<P, E> extends TemplateSetConfig {
+  name?: string;
+  props?: P;
+  env?: E;
+  test?: boolean;
+  warnIfNoStaticProps?: boolean;
+}
+
+let hasBeenLogged = false;
+
+export const DEV_MSG = () => {
+  const hash = (window as any).owl ? (window as any).owl.__info__.hash : "master";
+
+  return `Owl is running in 'dev' mode.
+
+This is not suitable for production use.
+See https://github.com/odoo/owl/blob/${hash}/doc/reference/app.md#configuration for more information.`;
+};
+
+declare global {
+  interface Window {
+    __OWL_DEVTOOLS__: {
+      apps: Set<App>;
+      Fiber: typeof Fiber;
+      RootFiber: typeof RootFiber;
+    };
+  }
+}
+
+window.__OWL_DEVTOOLS__ ||= {
+  apps: new Set<App>(),
+  Fiber: Fiber,
+  RootFiber: RootFiber,
+};
+
+export class App<
+  T extends abstract new (...args: any) => any = any,
+  P extends object = any,
+  E = any
+> extends TemplateSet {
+  static validateTarget = validateTarget;
+  static version = version;
+
+  name: string;
+  Root: ComponentConstructor<P, E>;
+  props: P;
+  env: E;
+  scheduler = new Scheduler();
+  root: ComponentNode<P, E> | null = null;
+  warnIfNoStaticProps: boolean;
+
+  constructor(Root: ComponentConstructor<P, E>, config: AppConfig<P, E> = {}) {
+    super(config);
+    this.name = config.name || "";
+    this.Root = Root;
+    window.__OWL_DEVTOOLS__.apps.add(this);
+    if (config.test) {
+      this.dev = true;
+    }
+    this.warnIfNoStaticProps = config.warnIfNoStaticProps || false;
+    if (this.dev && !config.test && !hasBeenLogged) {
+      console.info(DEV_MSG());
+      hasBeenLogged = true;
+    }
+    const env = config.env || {};
+    const descrs = Object.getOwnPropertyDescriptors(env);
+    this.env = Object.freeze(Object.create(Object.getPrototypeOf(env), descrs));
+    this.props = config.props || ({} as P);
+  }
+
+  mount(
+    target: HTMLElement | ShadowRoot,
+    options?: MountOptions
+  ): Promise<Component<P, E> & InstanceType<T>> {
+    App.validateTarget(target);
+    if (this.dev) {
+      validateProps(this.Root, this.props, { __owl__: { app: this } });
+    }
+    const node = this.makeNode(this.Root, this.props);
+    const prom = this.mountNode(node, target, options);
+    this.root = node;
+    return prom;
+  }
+
+  makeNode(Component: ComponentConstructor, props: any): ComponentNode {
+    return new ComponentNode(Component, props, this, null, null);
+  }
+
+  mountNode(node: ComponentNode, target: HTMLElement | ShadowRoot, options?: MountOptions) {
+    const promise: any = new Promise((resolve, reject) => {
+      let isResolved = false;
+      // manually set a onMounted callback.
+      // that way, we are independant from the current node.
+      node.mounted.push(() => {
+        resolve(node.component);
+        isResolved = true;
+      });
+
+      // Manually add the last resort error handler on the node
+      let handlers = nodeErrorHandlers.get(node);
+      if (!handlers) {
+        handlers = [];
+        nodeErrorHandlers.set(node, handlers);
+      }
+      handlers.unshift((e) => {
+        if (!isResolved) {
+          reject(e);
+        }
+        throw e;
+      });
+    });
+    node.mountComponent(target, options);
+    return promise;
+  }
+
+  destroy() {
+    if (this.root) {
+      this.scheduler.flush();
+      this.root.destroy();
+    }
+    window.__OWL_DEVTOOLS__.apps.delete(this);
+  }
+
+  createComponent<P extends Props>(
+    name: string | null,
+    isStatic: boolean,
+    hasSlotsProp: boolean,
+    hasDynamicPropList: boolean,
+    propList: string[]
+  ) {
+    const isDynamic = !isStatic;
+    let arePropsDifferent: (p1: Object, p2: Object) => boolean;
+    const hasNoProp = propList.length === 0;
+    if (hasSlotsProp) {
+      arePropsDifferent = (_1, _2) => true;
+    } else if (hasDynamicPropList) {
+      arePropsDifferent = function (props1: Props, props2: Props) {
+        for (let k in props1) {
+          if (props1[k] !== props2[k]) {
+            return true;
+          }
+        }
+        return Object.keys(props1).length !== Object.keys(props2).length;
+      };
+    } else if (hasNoProp) {
+      arePropsDifferent = (_1: any, _2: any) => false;
+    } else {
+      arePropsDifferent = function (props1: Props, props2: Props) {
+        for (let p of propList) {
+          if (props1[p] !== props2[p]) {
+            return true;
+          }
+        }
+        return false;
+      };
+    }
+
+    const updateAndRender = ComponentNode.prototype.updateAndRender;
+    const initiateRender = ComponentNode.prototype.initiateRender;
+
+    return (props: P, key: string, ctx: ComponentNode, parent: any, C: any) => {
+      let children = ctx.children;
+      let node: any = children[key];
+      if (isDynamic && node && node.component.constructor !== C) {
+        node = undefined;
+      }
+      const parentFiber = ctx.fiber!;
+      if (node) {
+        if (arePropsDifferent(node.props, props) || parentFiber.deep || node.forceNextRender) {
+          node.forceNextRender = false;
+          updateAndRender.call(node, props, parentFiber);
+        }
+      } else {
+        // new component
+        if (isStatic) {
+          const components = parent.constructor.components;
+          if (!components) {
+            throw new OwlError(
+              `Cannot find the definition of component "${name}", missing static components key in parent`
+            );
+          }
+          C = components[name as any];
+          if (!C) {
+            throw new OwlError(`Cannot find the definition of component "${name}"`);
+          } else if (!(C.prototype instanceof Component)) {
+            throw new OwlError(
+              `"${name}" is not a Component. It must inherit from the Component class`
+            );
+          }
+        }
+        node = new ComponentNode(C, props, this, ctx, key);
+        children[key] = node;
+        initiateRender.call(node, new Fiber(node, parentFiber));
+      }
+      parentFiber.childrenMap[key] = node;
+      return node;
+    };
+  }
+
+  handleError(...args: Parameters<typeof handleError>) {
+    return handleError(...args);
+  }
+}
+
+export async function mount<
+  T extends abstract new (...args: any) => any = any,
+  P extends object = any,
+  E = any
+>(
+  C: T & ComponentConstructor<P, E>,
+  target: HTMLElement,
+  config: AppConfig<P, E> & MountOptions = {}
+): Promise<Component<P, E> & InstanceType<T>> {
+  return new App(C, config).mount(target, config);
+}

src/runtime/blockdom/attributes.ts

@@ -93,6 +93,10 @@ function toClassObj(expr: string | number | { [c: string]: any }) {
       for (let key in expr as any) {
         const value = (expr as any)[key];
         if (value) {
+          key = trim.call(key);
+          if (!key) {
+            continue;
+          }
           const words = split.call(key, wordRegexp);
           for (let word of words) {
             result[word] = value;
@@ -136,33 +140,3 @@ export function updateClass(this: HTMLElement, val: any, oldVal: any) {
     }
   }
 }
-
-export function makePropSetter(name: string): Setter<HTMLElement> {
-  return function setProp(this: HTMLElement, value: any) {
-    // support 0, fallback to empty string for other falsy values
-    (this as any)[name] = value === 0 ? 0 : value || "";
-  };
-}
-
-export function isProp(tag: string, key: string): boolean {
-  switch (tag) {
-    case "input":
-      return (
-        key === "checked" ||
-        key === "indeterminate" ||
-        key === "value" ||
-        key === "readonly" ||
-        key === "disabled"
-      );
-    case "option":
-      return key === "selected" || key === "disabled";
-    case "textarea":
-      return key === "value" || key === "readonly" || key === "disabled";
-    case "select":
-      return key === "value" || key === "disabled";
-    case "button":
-    case "optgroup":
-      return key === "disabled";
-  }
-  return false;
-}

src/runtime/blockdom/block_compiler.ts

@@ -1,12 +1,5 @@
-import {
-  attrsSetter,
-  attrsUpdater,
-  createAttrUpdater,
-  isProp,
-  makePropSetter,
-  setClass,
-  updateClass,
-} from "./attributes";
+import { OwlError } from "../error_handling";
+import { attrsSetter, attrsUpdater, createAttrUpdater, setClass, updateClass } from "./attributes";
 import { config } from "./config";
 import { createEventHandler } from "./events";
 import type { VNode } from "./index";
@@ -24,6 +17,13 @@ const nodeGetNextSibling = getDescriptor(nodeProto, "nextSibling").get!;
 
 const NO_OP = () => {};
 
+function makePropSetter(name: string): Setter<HTMLElement> {
+  return function setProp(this: HTMLElement, value: any) {
+    // support 0, fallback to empty string for other falsy values
+    (this as any)[name] = value === 0 ? 0 : value ? value.valueOf() : "";
+  };
+}
+
 // -----------------------------------------------------------------------------
 // Main compiler code
 // -----------------------------------------------------------------------------
@@ -100,7 +100,7 @@ function normalizeNode(node: HTMLElement | Text) {
 interface DynamicInfo {
   idx: number;
   refIdx?: number;
-  type: "text" | "child" | "handler" | "attribute" | "attributes" | "ref";
+  type: "text" | "child" | "handler" | "attribute" | "attributes" | "property" | "ref";
   isOnlyChild?: boolean;
   name?: string;
   tag?: string;
@@ -156,6 +156,15 @@ function buildTree(
           : document.createElement(tagName);
       }
       if (el instanceof Element) {
+        if (!domParentTree) {
+          // some html elements may have side effects when setting their attributes.
+          // For example, setting the src attribute of an <img/> will trigger a
+          // request to get the corresponding image. This is something that we
+          // don't want at compile time. We avoid that by putting the content of
+          // the block in a <template/> element
+          const fragment = document.createElement("template").content;
+          fragment.appendChild(el);
+        }
         for (let i = 0; i < attrs.length; i++) {
           const attrName = attrs[i].name;
           const attrValue = attrs[i].value;
@@ -174,6 +183,14 @@ function buildTree(
               name: attrValue,
               tag: tagName,
             });
+          } else if (attrName.startsWith("block-property-")) {
+            const idx = parseInt(attrName.slice(15), 10);
+            info.push({
+              type: "property",
+              idx,
+              name: attrValue,
+              tag: tagName,
+            });
           } else if (attrName === "block-attributes") {
             info.push({
               type: "attributes",
@@ -245,7 +262,7 @@ function buildTree(
       };
     }
   }
-  throw new Error("boom");
+  throw new OwlError("boom");
 }
 
 function addRef(tree: IntermediateTree) {
@@ -367,15 +384,22 @@ function updateCtx(ctx: BlockCtx, tree: IntermediateTree) {
           };
         }
         break;
+      case "property": {
+        const refIdx = info.refIdx!;
+        const setProp = makePropSetter(info.name!);
+        ctx.locations.push({
+          idx: info.idx,
+          refIdx,
+          setData: setProp,
+          updateData: setProp,
+        });
+        break;
+      }
       case "attribute": {
         const refIdx = info.refIdx!;
         let updater: any;
         let setter: any;
-        if (isProp(info.tag!, info.name!)) {
-          const setProp = makePropSetter(info.name!);
-          setter = setProp;
-          updater = setProp;
-        } else if (info.name === "class") {
+        if (info.name === "class") {
           setter = setClass;
           updater = updateClass;
         } else {
@@ -507,9 +531,13 @@ function createBlockClass(template: HTMLElement, ctx: BlockCtx): BlockClass {
       return this.el!;
     }
 
-    moveBefore(other: Block | null, afterNode: Node | null) {
-      const target = other ? other.el! : afterNode;
-      nodeInsertBefore.call(this.parentEl, this.el!, target);
+    moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+      this.parentEl = parent;
+      nodeInsertBefore.call(parent, this.el!, node);
+    }
+
+    moveBeforeVNode(other: Block | null, afterNode: Node | null) {
+      nodeInsertBefore.call(this.parentEl, this.el!, other ? other.el! : afterNode);
     }
 
     toString() {

src/runtime/blockdom/event_catcher.ts

@@ -0,0 +1,111 @@
+import { createEventHandler } from "./events";
+import type { VNode } from "./index";
+
+type EventsSpec = { [name: string]: number };
+
+type Catcher = (child: VNode, handlers: any[]) => VNode;
+
+export function createCatcher(eventsSpec: EventsSpec): Catcher {
+  const n = Object.keys(eventsSpec).length;
+
+  class VCatcher {
+    child: VNode;
+    handlerData: any[];
+    handlerFns: any[] = [];
+
+    parentEl?: HTMLElement | undefined;
+    afterNode: Text | null = null;
+
+    constructor(child: VNode, handlers: any[]) {
+      this.child = child;
+      this.handlerData = handlers;
+    }
+
+    mount(parent: HTMLElement, afterNode: Node | null) {
+      this.parentEl = parent;
+      this.child.mount(parent, afterNode);
+      this.afterNode = document.createTextNode("");
+      parent.insertBefore(this.afterNode, afterNode);
+      this.wrapHandlerData();
+      for (let name in eventsSpec) {
+        const index = eventsSpec[name];
+        const handler = createEventHandler(name);
+        this.handlerFns[index] = handler;
+        handler.setup.call(parent, this.handlerData[index]);
+      }
+    }
+
+    wrapHandlerData() {
+      for (let i = 0; i < n; i++) {
+        let handler = this.handlerData[i];
+        // handler = [...mods, fn, comp], so we need to replace second to last elem
+        let idx = handler.length - 2;
+        let origFn = handler[idx];
+        const self = this;
+        handler[idx] = function (ev: any) {
+          const target = ev.target;
+          let currentNode: any = self.child.firstNode();
+          const afterNode = self.afterNode;
+          while (currentNode && currentNode !== afterNode) {
+            if (currentNode.contains(target)) {
+              return origFn.call(this, ev);
+            }
+            currentNode = currentNode.nextSibling;
+          }
+        };
+      }
+    }
+
+    moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+      this.parentEl = parent;
+      this.child.moveBeforeDOMNode(node, parent);
+      parent!.insertBefore(this.afterNode!, node);
+    }
+
+    moveBeforeVNode(other: VCatcher | null, afterNode: Node | null) {
+      if (other) {
+        // check this with @ged-odoo for use in foreach
+        afterNode = other.firstNode() || afterNode;
+      }
+      this.child.moveBeforeVNode(other ? other.child : null, afterNode);
+      this.parentEl!.insertBefore(this.afterNode!, afterNode);
+    }
+
+    patch(other: VCatcher, withBeforeRemove: boolean) {
+      if (this === other) {
+        return;
+      }
+      this.handlerData = other.handlerData;
+      this.wrapHandlerData();
+      for (let i = 0; i < n; i++) {
+        this.handlerFns[i].update.call(this.parentEl!, this.handlerData[i]);
+      }
+
+      this.child.patch(other.child, withBeforeRemove);
+    }
+
+    beforeRemove() {
+      this.child.beforeRemove();
+    }
+
+    remove() {
+      for (let i = 0; i < n; i++) {
+        this.handlerFns[i].remove.call(this.parentEl!);
+      }
+      this.child.remove();
+      this.afterNode!.remove();
+    }
+
+    firstNode(): Node | undefined {
+      return this.child.firstNode();
+    }
+
+    toString(): string {
+      return this.child.toString();
+    }
+  }
+
+  return function (child: VNode, handlers: any[]): VNode<VCatcher> {
+    return new VCatcher(child, handlers);
+  };
+}

src/runtime/blockdom/events.ts

@@ -1,3 +1,4 @@
+import { inOwnerDocument } from "../utils";
 import { config } from "./config";
 
 type EventHandlerSetter = (this: HTMLElement, data: any) => void;
@@ -27,8 +28,8 @@ function createElementHandler(evName: string, capture: boolean = false): EventHa
   }
 
   function listener(ev: Event) {
-    const currentTarget = ev.currentTarget;
-    if (!currentTarget || !document.contains(currentTarget as HTMLElement)) return;
+    const currentTarget = ev.currentTarget as HTMLElement;
+    if (!currentTarget || !inOwnerDocument(currentTarget)) return;
     const data = (currentTarget as any)[eventKey];
     if (!data) return;
     config.mainEventHandler(data, ev, currentTarget);

src/runtime/blockdom/html.ts

@@ -29,14 +29,18 @@ class VHtml {
     }
   }
 
-  moveBefore(other: VHtml | null, afterNode: Node | null) {
-    const target = other ? other.content[0] : afterNode;
-    const parent = this.parentEl;
+  moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+    this.parentEl = parent;
     for (let elem of this.content) {
-      nodeInsertBefore.call(parent, elem, target);
+      nodeInsertBefore.call(parent, elem, node);
     }
   }
 
+  moveBeforeVNode(other: VHtml | null, afterNode: Node | null) {
+    const target = other ? other.content[0] : afterNode;
+    this.moveBeforeDOMNode(target);
+  }
+
   patch(other: VHtml) {
     if (this === other) {
       return;

src/runtime/blockdom/index.ts

@@ -10,7 +10,8 @@ export { createCatcher } from "./event_catcher";
 
 export interface VNode<T = any> {
   mount(parent: HTMLElement, afterNode: Node | null): void;
-  moveBefore(other: T | null, afterNode: Node | null): void;
+  moveBeforeDOMNode(node: Node | null, parent?: HTMLElement): void;
+  moveBeforeVNode(other: T | null, afterNode: Node | null): void;
   patch(other: T, withBeforeRemove: boolean): void;
   beforeRemove(): void;
   remove(): void;

src/runtime/blockdom/list.ts

@@ -38,14 +38,23 @@ class VList {
     this.parentEl = parent;
   }
 
-  moveBefore(other: VList | null, afterNode: Node | null) {
+  moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+    this.parentEl = parent;
+    const children = this.children;
+    for (let i = 0, l = children.length; i < l; i++) {
+      children[i].moveBeforeDOMNode(node, parent);
+    }
+    parent!.insertBefore(this.anchor!, node);
+  }
+
+  moveBeforeVNode(other: VList | null, afterNode: Node | null) {
     if (other) {
       const next = other!.children[0];
       afterNode = (next ? next.firstNode() : other!.anchor) || null;
     }
     const children = this.children;
     for (let i = 0, l = children.length; i < l; i++) {
-      children[i].moveBefore(null, afterNode);
+      children[i].moveBeforeVNode(null, afterNode);
     }
     this.parentEl!.insertBefore(this.anchor!, afterNode);
   }
@@ -66,7 +75,7 @@ class VList {
       patch: cPatch,
       remove: cRemove,
       beforeRemove,
-      moveBefore: cMoveBefore,
+      moveBeforeVNode: cMoveBefore,
       firstNode: cFirstNode,
     } = proto;
 

src/runtime/blockdom/multi.ts

@@ -38,7 +38,22 @@ export class VMulti {
     this.parentEl = parent;
   }
 
-  moveBefore(other: VMulti | null, afterNode: Node | null) {
+  moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+    this.parentEl = parent;
+    const children = this.children;
+    const anchors = this.anchors;
+    for (let i = 0, l = children.length; i < l; i++) {
+      let child = children[i];
+      if (child) {
+        child.moveBeforeDOMNode(node, parent);
+      } else {
+        const anchor = anchors![i];
+        nodeInsertBefore.call(parent, anchor, node);
+      }
+    }
+  }
+
+  moveBeforeVNode(other: VMulti | null, afterNode: Node | null) {
     if (other) {
       const next = other!.children[0];
       afterNode = (next ? next.firstNode() : other!.anchors![0]) || null;
@@ -49,7 +64,7 @@ export class VMulti {
     for (let i = 0, l = children.length; i < l; i++) {
       let child = children[i];
       if (child) {
-        child.moveBefore(null, afterNode);
+        child.moveBeforeVNode(null, afterNode);
       } else {
         const anchor = anchors![i];
         nodeInsertBefore.call(parent, anchor, afterNode);

src/runtime/blockdom/text.ts

@@ -23,9 +23,13 @@ abstract class VSimpleNode {
     this.el = node;
   }
 
-  moveBefore(other: VText | null, afterNode: Node | null) {
-    const target = other ? other.el! : afterNode;
-    nodeInsertBefore.call(this.parentEl, this.el!, target);
+  moveBeforeDOMNode(node: Node | null, parent = this.parentEl) {
+    this.parentEl = parent;
+    nodeInsertBefore.call(parent, this.el!, node);
+  }
+
+  moveBeforeVNode(other: VText | null, afterNode: Node | null) {
+    nodeInsertBefore.call(this.parentEl, this.el!, other ? other.el! : afterNode);
   }
 
   beforeRemove() {}

src/runtime/blockdom/toggler.ts

@@ -20,8 +20,12 @@ class VToggler {
     this.child.mount(parent, afterNode);
   }
 
-  moveBefore(other: VToggler | null, afterNode: Node | null) {
-    this.child.moveBefore(other ? other.child : null, afterNode);
+  moveBeforeDOMNode(node: Node | null, parent?: HTMLElement) {
+    this.child.moveBeforeDOMNode(node, parent);
+  }
+
+  moveBeforeVNode(other: VToggler | null, afterNode: Node | null) {
+    this.moveBeforeDOMNode((other && other.firstNode()) || afterNode);
   }
 
   patch(other: VToggler, withBeforeRemove: boolean) {

src/runtime/component.ts

@@ -1,15 +1,17 @@
+import { Schema } from "./validation";
 import type { ComponentNode } from "./component_node";
 
 // -----------------------------------------------------------------------------
 //  Component Class
 // -----------------------------------------------------------------------------
 
-type Props = { [key: string]: any };
+export type Props = { [key: string]: any };
 
 interface StaticComponentProperties {
   template: string;
   defaultProps?: any;
-  props?: any;
+  props?: Schema;
+  components?: { [componentName: string]: ComponentConstructor };
 }
 
 export type ComponentConstructor<P extends Props = any, E = any> = (new (
@@ -37,6 +39,6 @@ export class Component<Props = any, Env = any> {
   setup() {}
 
   render(deep: boolean = false) {
-    this.__owl__.render(deep);
+    this.__owl__.render(deep === true);
   }
 }

src/runtime/component_node.ts

@@ -1,25 +1,17 @@
-import type { App, Env } from "../app/app";
-import { BDom, VNode } from "../blockdom";
-import {
-  clearReactivesForCallback,
-  getSubscriptions,
-  NonReactive,
-  Reactive,
-  reactive,
-  TARGET,
-} from "../reactivity";
-import { batched, Callback } from "../utils";
-import { Component, ComponentConstructor } from "./component";
-import { fibersInError, handleError } from "./error_handling";
+import type { App, Env } from "./app";
+import { BDom, VNode } from "./blockdom";
+import { Component, ComponentConstructor, Props } from "./component";
+import { fibersInError, OwlError } from "./error_handling";
 import { Fiber, makeChildFiber, makeRootFiber, MountFiber, MountOptions } from "./fibers";
-import { applyDefaultProps } from "./props_validation";
+import { clearReactivesForCallback, getSubscriptions, reactive, targets } from "./reactivity";
 import { STATUS } from "./status";
+import { batched, Callback } from "./utils";
 
 let currentNode: ComponentNode | null = null;
 
 export function getCurrent(): ComponentNode {
   if (!currentNode) {
-    throw new Error("No active component (a hook function should only be called in 'setup')");
+    throw new OwlError("No active component (a hook function should only be called in 'setup')");
   }
   return currentNode;
 }
@@ -28,6 +20,16 @@ export function useComponent(): Component {
   return currentNode!.component;
 }
 
+/**
+ * Apply default props (only top level).
+ */
+function applyDefaultProps<P extends object>(props: P, defaultProps: Partial<P>) {
+  for (let propName in defaultProps) {
+    if (props[propName] === undefined) {
+      (props as any)[propName] = defaultProps[propName];
+    }
+  }
+}
 // -----------------------------------------------------------------------------
 // Integration with reactivity system (useState)
 // -----------------------------------------------------------------------------
@@ -43,11 +45,11 @@ const batchedRenderFunctions = new WeakMap<ComponentNode, Callback>();
  *  relevant changes
  * @see reactive
  */
-export function useState<T extends object>(state: T): Reactive<T> | NonReactive<T> {
+export function useState<T extends object>(state: T): T {
   const node = getCurrent();
   let render = batchedRenderFunctions.get(node)!;
   if (!render) {
-    render = batched(node.render.bind(node));
+    render = batched(node.render.bind(node, false));
     batchedRenderFunctions.set(node, render);
     // manual implementation of onWillDestroy to break cyclic dependency
     node.willDestroy.push(clearReactivesForCallback.bind(null, render));
@@ -55,75 +57,13 @@ export function useState<T extends object>(state: T): Reactive<T> | NonReactive<
   return reactive(state, render);
 }
 
-// -----------------------------------------------------------------------------
-// component function (used in compiled template code)
-// -----------------------------------------------------------------------------
-type Props = { [key: string]: any };
-
-function arePropsDifferent(props1: Props, props2: Props): boolean {
-  for (let k in props1) {
-    if (props1[k] !== props2[k]) {
-      return true;
-    }
-  }
-  return Object.keys(props1).length !== Object.keys(props2).length;
-}
-
-export function component<P extends object>(
-  name: string | ComponentConstructor<P>,
-  props: P,
-  key: string,
-  ctx: ComponentNode,
-  parent: any
-): ComponentNode<P> {
-  let node: any = ctx.children[key];
-  let isDynamic = typeof name !== "string";
-
-  if (node && node.status === STATUS.DESTROYED) {
-    node = undefined;
-  }
-  if (isDynamic && node && node.component.constructor !== name) {
-    node = undefined;
-  }
-
-  const parentFiber = ctx.fiber!;
-  if (node) {
-    let shouldRender = node.forceNextRender;
-    if (shouldRender) {
-      node.forceNextRender = false;
-    } else {
-      const currentProps = node.component.props[TARGET];
-      shouldRender = parentFiber.deep || arePropsDifferent(currentProps, props);
-    }
-    if (shouldRender) {
-      node.updateAndRender(props, parentFiber);
-    }
-  } else {
-    // new component
-    let C;
-    if (isDynamic) {
-      C = name;
-    } else {
-      C = parent.constructor.components[name as any];
-      if (!C) {
-        throw new Error(`Cannot find the definition of component "${name}"`);
-      }
-    }
-    node = new ComponentNode(C, props, ctx.app, ctx, key);
-    ctx.children[key] = node;
-    node.initiateRender(new Fiber(node, parentFiber));
-  }
-  parentFiber.childrenMap[key] = node;
-  return node;
-}
-
 // -----------------------------------------------------------------------------
 //  Component VNode class
 // -----------------------------------------------------------------------------
 
 type LifecycleHook = Function;
 
-export class ComponentNode<P extends object = any, E = any> implements VNode<ComponentNode<P, E>> {
+export class ComponentNode<P extends Props = any, E = any> implements VNode<ComponentNode<P, E>> {
   el?: HTMLElement | Text | undefined;
   app: App;
   fiber: Fiber | null = null;
@@ -132,10 +72,11 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
   status: STATUS = STATUS.NEW;
   forceNextRender: boolean = false;
   parentKey: string | null;
+  props: P;
+  nextProps: P | null = null;
 
   renderFn: Function;
   parent: ComponentNode | null;
-  level: number;
   childEnv: Env;
   children: { [key: string]: ComponentNode } = Object.create(null);
   refs: any = {};
@@ -158,14 +99,24 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     currentNode = this;
     this.app = app;
     this.parent = parent;
+    this.props = props;
     this.parentKey = parentKey;
-    this.level = parent ? parent.level + 1 : 0;
-    applyDefaultProps(props, C);
+    const defaultProps = C.defaultProps;
+    props = Object.assign({}, props);
+    if (defaultProps) {
+      applyDefaultProps(props, defaultProps);
+    }
     const env = (parent && parent.childEnv) || app.env;
     this.childEnv = env;
-    props = useState(props);
-    this.component = new C(props, env, this) as any;
-    this.renderFn = app.getTemplate(C.template).bind(this.component, this.component, this);
+    for (const key in props) {
+      const prop = props[key];
+      if (prop && typeof prop === "object" && targets.has(prop)) {
+        props[key] = useState(prop);
+      }
+    }
+    this.component = new C(props, env, this);
+    const ctx = Object.assign(Object.create(this.component), { this: this.component });
+    this.renderFn = app.getTemplate(C.template).bind(this.component, ctx, this);
     this.component.setup();
     currentNode = null;
   }
@@ -185,7 +136,7 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     try {
       await Promise.all(this.willStart.map((f) => f.call(component)));
     } catch (e) {
-      handleError({ node: this, error: e });
+      this.app.handleError({ node: this, error: e });
       return;
     }
     if (this.status === STATUS.NEW && this.fiber === fiber) {
@@ -193,7 +144,7 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     }
   }
 
-  async render(deep: boolean = false) {
+  async render(deep: boolean) {
     let current = this.fiber;
     if (current && (current.root!.locked || (current as any).bdom === true)) {
       await Promise.resolve();
@@ -263,21 +214,31 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
           cb.call(component);
         }
       } catch (e) {
-        handleError({ error: e, node: this });
+        this.app.handleError({ error: e, node: this });
       }
     }
     this.status = STATUS.DESTROYED;
   }
 
-  async updateAndRender(props: any, parentFiber: Fiber) {
+  async updateAndRender(props: P, parentFiber: Fiber) {
+    this.nextProps = props;
+    props = Object.assign({}, props);
     // update
     const fiber = makeChildFiber(this, parentFiber);
     this.fiber = fiber;
     const component = this.component;
-    applyDefaultProps(props, component.constructor as any);
+    const defaultProps = (component.constructor as any).defaultProps;
+    if (defaultProps) {
+      applyDefaultProps(props, defaultProps);
+    }
 
     currentNode = this;
-    props = useState(props);
+    for (const key in props) {
+      const prop = props[key];
+      if (prop && typeof prop === "object" && targets.has(prop)) {
+        props[key] = useState(prop);
+      }
+    }
     currentNode = null;
     const prom = Promise.all(this.willUpdateProps.map((f) => f.call(component, props)));
     await prom;
@@ -320,6 +281,19 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     }
   }
 
+  /**
+   * Sets a ref to a given HTMLElement.
+   *
+   * @param name the name of the ref to set
+   * @param el the HTMLElement to set the ref to. The ref is not set if the el
+   *  is null, but useRef will not return elements that are not in the DOM
+   */
+  setRef(name: string, el: HTMLElement | null) {
+    if (el) {
+      this.refs[name] = el;
+    }
+  }
+
   // ---------------------------------------------------------------------------
   // Block DOM methods
   // ---------------------------------------------------------------------------
@@ -339,8 +313,12 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     this.fiber = null;
   }
 
-  moveBefore(other: ComponentNode | null, afterNode: Node | null) {
-    this.bdom!.moveBefore(other ? other.bdom : null, afterNode);
+  moveBeforeDOMNode(node: Node | null, parent?: HTMLElement): void {
+    this.bdom!.moveBeforeDOMNode(node, parent);
+  }
+
+  moveBeforeVNode(other: ComponentNode<P, E> | null, afterNode: Node | null) {
+    this.bdom!.moveBeforeVNode(other ? other.bdom : null, afterNode);
   }
 
   patch() {
@@ -349,13 +327,20 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
       // by the component will be patched independently in the appropriate
       // fiber.complete
       this._patch();
+      this.props = this.nextProps!;
     }
   }
   _patch() {
-    const hasChildren = Object.keys(this.children).length > 0;
-    this.children = this.fiber!.childrenMap;
-    this.bdom!.patch(this!.fiber!.bdom!, hasChildren);
-    this.fiber!.appliedToDom = true;
+    let hasChildren = false;
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    for (let _k in this.children) {
+      hasChildren = true;
+      break;
+    }
+    const fiber = this.fiber!;
+    this.children = fiber.childrenMap;
+    this.bdom!.patch(fiber.bdom!, hasChildren);
+    fiber.appliedToDom = true;
     this.fiber = null;
   }
 

src/runtime/error_handling.ts

@@ -1,6 +1,11 @@
 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();
@@ -37,7 +42,14 @@ function _handleError(node: ComponentNode | null, error: any): boolean {
 
 type ErrorParams = { error: any } & ({ node: ComponentNode } | { fiber: Fiber });
 export function handleError(params: ErrorParams) {
-  const error = params.error;
+  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!;
 
@@ -59,5 +71,6 @@ export function handleError(params: ErrorParams) {
     } catch (e) {
       console.error(e);
     }
+    throw error;
   }
 }

src/runtime/event_handling.ts

@@ -1,5 +1,6 @@
-import { filterOutModifiersFromData } from "../blockdom/config";
+import { filterOutModifiersFromData } from "./blockdom/config";
 import { STATUS } from "./status";
+import { OwlError } from "./error_handling";
 
 export const mainEventHandler = (data: any, ev: Event, currentTarget?: EventTarget | null) => {
   const { data: _data, modifiers } = filterOutModifiersFromData(data);
@@ -33,7 +34,7 @@ export const mainEventHandler = (data: any, ev: Event, currentTarget?: EventTarg
   if (Object.hasOwnProperty.call(data, 0)) {
     const handler = data[0];
     if (typeof handler !== "function") {
-      throw new Error(`Invalid handler (expected a function, received: '${handler}')`);
+      throw new OwlError(`Invalid handler (expected a function, received: '${handler}')`);
     }
     let node = data[1] ? data[1].__owl__ : null;
     if (node ? node.status === STATUS.MOUNTED : true) {

src/runtime/fibers.ts

@@ -1,6 +1,6 @@
-import { BDom, mount } from "../blockdom";
+import { BDom, mount } from "./blockdom";
 import type { ComponentNode } from "./component_node";
-import { fibersInError, handleError } from "./error_handling";
+import { fibersInError, OwlError } from "./error_handling";
 import { STATUS } from "./status";
 
 export function makeChildFiber(node: ComponentNode, parent: Fiber): Fiber {
@@ -42,6 +42,10 @@ export function makeRootFiber(node: ComponentNode): Fiber {
   return fiber;
 }
 
+function throwOnRender() {
+  throw new OwlError("Attempted to render cancelled fiber");
+}
+
 /**
  * @returns number of not-yet rendered fibers cancelled
  */
@@ -49,8 +53,10 @@ function cancelFibers(fibers: Fiber[]): number {
   let result = 0;
   for (let fiber of fibers) {
     let node = fiber.node;
+    fiber.render = throwOnRender;
     if (node.status === STATUS.NEW) {
       node.destroy();
+      delete node.parent!.children[node.parentKey!];
     }
     node.fiber = null;
     if (fiber.bdom) {
@@ -124,7 +130,7 @@ export class Fiber {
         (this.bdom as any) = true;
         this.bdom = node.renderFn();
       } catch (e) {
-        handleError({ node, error: e });
+        node.app.handleError({ node, error: e });
       }
       root.setCounter(root.counter - 1);
     }
@@ -189,7 +195,7 @@ export class RootFiber extends Fiber {
       }
     } catch (e) {
       this.locked = false;
-      handleError({ fiber: current || this, error: e });
+      node.app.handleError({ fiber: current || this, error: e });
     }
   }
 
@@ -253,7 +259,7 @@ export class MountFiber extends RootFiber {
         }
       }
     } catch (e) {
-      handleError({ fiber: current as Fiber, error: e });
+      this.node.app.handleError({ fiber: current as Fiber, error: e });
     }
   }
 }

src/runtime/hooks.ts

@@ -1,6 +1,7 @@
-import type { Env } from "./app/app";
-import { getCurrent } from "./component/component_node";
-import { onMounted, onPatched, onWillUnmount } from "./component/lifecycle_hooks";
+import type { Env } from "./app";
+import { getCurrent } from "./component_node";
+import { onMounted, onPatched, onWillUnmount } from "./lifecycle_hooks";
+import { inOwnerDocument } from "./utils";
 
 // -----------------------------------------------------------------------------
 // useRef
@@ -15,7 +16,8 @@ export function useRef<T extends HTMLElement = HTMLElement>(name: string): { el:
   const refs = node.refs;
   return {
     get el(): T | null {
-      return refs[name] || null;
+      const el = refs[name];
+      return inOwnerDocument(el) ? el : null;
     },
   };
 }
@@ -117,7 +119,7 @@ export function useEffect(effect: Effect, computeDependencies: () => any[] = ()
  *  `useExternalListener(window, 'click', this._doSomething);`
  * */
 export function useExternalListener(
-  target: HTMLElement | typeof window,
+  target: EventTarget,
   eventName: string,
   handler: EventListener,
   eventParams?: AddEventListenerOptions

src/runtime/index.ts

@@ -0,0 +1,62 @@
+import { App } from "./app";
+import {
+  config,
+  createBlock,
+  html,
+  list,
+  mount as blockMount,
+  multi,
+  patch,
+  remove,
+  text,
+  toggler,
+  comment,
+} from "./blockdom";
+import { mainEventHandler } from "./event_handling";
+
+config.shouldNormalizeDom = false;
+config.mainEventHandler = mainEventHandler;
+
+export const blockDom = {
+  config,
+  // bdom entry points
+  mount: blockMount,
+  patch,
+  remove,
+  // bdom block types
+  list,
+  multi,
+  text,
+  toggler,
+  createBlock,
+  html,
+  comment,
+};
+
+export { App, mount } from "./app";
+export { xml } from "./template_set";
+export { Component } from "./component";
+export type { ComponentConstructor } from "./component";
+export { useComponent, useState } from "./component_node";
+export { status } from "./status";
+export { reactive, markRaw, toRaw } from "./reactivity";
+export { useEffect, useEnv, useExternalListener, useRef, useChildSubEnv, useSubEnv } from "./hooks";
+export { EventBus, whenReady, loadFile, markup } from "./utils";
+export {
+  onWillStart,
+  onMounted,
+  onWillUnmount,
+  onWillUpdateProps,
+  onWillPatch,
+  onPatched,
+  onWillRender,
+  onRendered,
+  onWillDestroy,
+  onError,
+} from "./lifecycle_hooks";
+export { validate, validateType } from "./validation";
+export { OwlError } from "./error_handling";
+
+export const __info__ = {
+  version: App.version,
+};

src/runtime/lifecycle_hooks.ts

@@ -1,21 +1,30 @@
 import { getCurrent } from "./component_node";
-import { nodeErrorHandlers } from "./error_handling";
+import { nodeErrorHandlers, OwlError } from "./error_handling";
 
 const TIMEOUT = Symbol("timeout");
 function wrapError(fn: (...args: any[]) => any, hookName: string) {
-  const error = new Error(`The following error occurred in ${hookName}: `) as Error & {
+  const error = new OwlError(`The following error occurred in ${hookName}: `) as Error & {
     cause: any;
   };
-  const timeoutError = new Error(`${hookName}'s promise hasn't resolved after 3 seconds`);
+  const timeoutError = new OwlError(`${hookName}'s promise hasn't resolved after 3 seconds`);
   const node = getCurrent();
   return (...args: any[]) => {
+    const onError = (cause: any) => {
+      error.cause = cause;
+      if (cause instanceof Error) {
+        error.message += `"${cause.message}"`;
+      } else {
+        error.message = `Something that is not an Error was thrown in ${hookName} (see this Error's "cause" property)`;
+      }
+      throw error;
+    };
     try {
       const result = fn(...args);
       if (result instanceof Promise) {
         if (hookName === "onWillStart" || hookName === "onWillUpdateProps") {
           const fiber = node.fiber;
           Promise.race([
-            result,
+            result.catch(() => {}),
             new Promise((resolve) => setTimeout(() => resolve(TIMEOUT), 3000)),
           ]).then((res) => {
             if (res === TIMEOUT && node.fiber === fiber) {
@@ -23,20 +32,11 @@ function wrapError(fn: (...args: any[]) => any, hookName: string) {
             }
           });
         }
-        return result.catch((cause) => {
-          error.cause = cause;
-          if (cause instanceof Error) {
-            error.message += `"${cause.message}"`;
-          }
-          throw error;
-        });
+        return result.catch(onError);
       }
       return result;
     } catch (cause) {
-      if (cause instanceof Error) {
-        error.message += `"${cause.message}"`;
-      }
-      throw error;
+      onError(cause);
     }
   };
 }
@@ -63,7 +63,7 @@ export function onMounted(fn: () => void | any) {
   node.mounted.push(decorate(fn.bind(node.component), "onMounted"));
 }
 
-export function onWillPatch(fn: () => Promise<void> | any | void) {
+export function onWillPatch(fn: () => any | void) {
   const node = getCurrent();
   const decorate = node.app.dev ? wrapError : (fn: any) => fn;
   node.willPatch.unshift(decorate(fn.bind(node.component), "onWillPatch"));
@@ -75,13 +75,13 @@ export function onPatched(fn: () => void | any) {
   node.patched.push(decorate(fn.bind(node.component), "onPatched"));
 }
 
-export function onWillUnmount(fn: () => Promise<void> | void | any) {
+export function onWillUnmount(fn: () => void | any) {
   const node = getCurrent();
   const decorate = node.app.dev ? wrapError : (fn: any) => fn;
   node.willUnmount.unshift(decorate(fn.bind(node.component), "onWillUnmount"));
 }
 
-export function onWillDestroy(fn: () => Promise<void> | void | any) {
+export function onWillDestroy(fn: () => void | any) {
   const node = getCurrent();
   const decorate = node.app.dev ? wrapError : (fn: any) => fn;
   node.willDestroy.push(decorate(fn.bind(node.component), "onWillDestroy"));

src/runtime/portal.ts

@@ -0,0 +1,90 @@
+import { onMounted, onWillUnmount } from "./lifecycle_hooks";
+import { BDom, text, VNode } from "./blockdom";
+import { Component } from "./component";
+import { OwlError } from "./error_handling";
+
+const VText: any = text("").constructor;
+
+class VPortal extends VText implements Partial<VNode<VPortal>> {
+  content: BDom | null;
+  selector: string;
+  target: HTMLElement | null = null;
+
+  constructor(selector: string, content: BDom) {
+    super("");
+    this.selector = selector;
+    this.content = content;
+  }
+
+  mount(parent: HTMLElement, anchor: ChildNode) {
+    super.mount(parent, anchor);
+    this.target = document.querySelector(this.selector) as any;
+    if (this.target) {
+      this.content!.mount(this.target!, null);
+    } else {
+      this.content!.mount(parent, anchor);
+    }
+  }
+
+  beforeRemove() {
+    this.content!.beforeRemove();
+  }
+  remove() {
+    if (this.content) {
+      super.remove();
+      this.content!.remove();
+      this.content = null;
+    }
+  }
+
+  patch(other: VPortal) {
+    super.patch(other);
+    if (this.content) {
+      this.content.patch(other.content!, true);
+    } else {
+      this.content = other.content;
+      this.content!.mount(this.target!, null);
+    }
+  }
+}
+
+/**
+ * kind of similar to <t t-slot="default"/>, but it wraps it around a VPortal
+ */
+export function portalTemplate(app: any, bdom: any, helpers: any) {
+  let { callSlot } = helpers;
+  return function template(ctx: any, node: any, key = ""): any {
+    return new VPortal(ctx.props.target, callSlot(ctx, node, key, "default", false, null));
+  };
+}
+
+export class Portal extends Component {
+  static template = "__portal__";
+  static props = {
+    target: {
+      type: String,
+    },
+    slots: true,
+  };
+
+  setup() {
+    const node: any = this.__owl__;
+
+    onMounted(() => {
+      const portal: VPortal = node.bdom;
+      if (!portal.target) {
+        const target: HTMLElement = document.querySelector(this.props.target);
+        if (target) {
+          portal.content!.moveBeforeDOMNode(target.firstChild, target);
+        } else {
+          throw new OwlError("invalid portal target");
+        }
+      }
+    });
+
+    onWillUnmount(() => {
+      const portal: VPortal = node.bdom;
+      portal.remove();
+    });
+  }
+}

src/runtime/reactivity.ts

@@ -1,24 +1,22 @@
-import { Callback } from "./utils";
+import type { Callback } from "./utils";
+import { OwlError } from "./error_handling";
 
-// Allows to get the target of a Reactive (used for making a new Reactive from the underlying object)
-export const TARGET = Symbol("Target");
-// Escape hatch to prevent reactivity system to turn something into a reactive
-const SKIP = Symbol("Skip");
 // Special key to subscribe to, to be notified of key creation/deletion
 const KEYCHANGES = Symbol("Key changes");
+// Used to specify the absence of a callback, can be used as WeakMap key but
+// should only be used as a sentinel value and never called.
+const NO_CALLBACK = () => {
+  throw new Error("Called NO_CALLBACK. Owl is broken, please report this to the maintainers.");
+};
 
+// The following types only exist to signify places where objects are expected
+// to be reactive or not, they provide no type checking benefit over "object"
 type Target = object;
+type Reactive<T extends Target> = T;
+
 type Collection = Set<any> | Map<any, any> | WeakMap<any, any>;
 type CollectionRawType = "Set" | "Map" | "WeakMap";
 
-export type Reactive<T extends Target = Target> = T & {
-  [TARGET]: any;
-};
-
-export type NonReactive<T extends Target = Target> = T & {
-  [SKIP]: any;
-};
-
 const objectToString = Object.prototype.toString;
 const objectHasOwnProperty = Object.prototype.hasOwnProperty;
 
@@ -35,7 +33,7 @@ const COLLECTION_RAWTYPES = new Set(["Set", "Map", "WeakMap"]);
  * @returns the raw type of the object
  */
 function rawType(obj: any) {
-  return objectToString.call(obj).slice(8, -1);
+  return objectToString.call(toRaw(obj)).slice(8, -1);
 }
 /**
  * Checks whether a given value can be made into a reactive object.
@@ -60,15 +58,16 @@ function possiblyReactive(val: any, cb: Callback) {
   return canBeMadeReactive(val) ? reactive(val, cb) : val;
 }
 
+const skipped = new WeakSet<Target>();
 /**
  * Mark an object or array so that it is ignored by the reactivity system
  *
  * @param value the value to mark
  * @returns the object itself
  */
-export function markRaw<T extends Target>(value: T): NonReactive<T> {
-  (value as any)[SKIP] = true;
-  return value as NonReactive<T>;
+export function markRaw<T extends Target>(value: T): T {
+  skipped.add(value);
+  return value;
 }
 
 /**
@@ -77,8 +76,8 @@ export function markRaw<T extends Target>(value: T): NonReactive<T> {
  * @param value a reactive value
  * @returns the underlying value
  */
-export function toRaw<T extends object>(value: Reactive<T>): T {
-  return value[TARGET] || value;
+export function toRaw<T extends Target, U extends Reactive<T>>(value: U | T): T {
+  return targets.has(value) ? (targets.get(value) as T) : value;
 }
 
 const targetToKeysToCallbacks = new WeakMap<Target, Map<PropertyKey, Set<Callback>>>();
@@ -92,6 +91,9 @@ const targetToKeysToCallbacks = new WeakMap<Target, Map<PropertyKey, Set<Callbac
  * @param callback the function to call when the key changes
  */
 function observeTargetKey(target: Target, key: PropertyKey, callback: Callback): void {
+  if (callback === NO_CALLBACK) {
+    return;
+  }
   if (!targetToKeysToCallbacks.get(target)) {
     targetToKeysToCallbacks.set(target, new Map());
   }
@@ -146,8 +148,11 @@ export function clearReactivesForCallback(callback: Callback): void {
     if (!observedKeys) {
       continue;
     }
-    for (const callbacks of observedKeys.values()) {
+    for (const [key, callbacks] of observedKeys.entries()) {
       callbacks.delete(callback);
+      if (!callbacks.size) {
+        observedKeys.delete(key);
+      }
     }
   }
   targetsToClear.clear();
@@ -157,14 +162,20 @@ export function getSubscriptions(callback: Callback) {
   const targets = callbacksToTargets.get(callback) || [];
   return [...targets].map((target) => {
     const keysToCallbacks = targetToKeysToCallbacks.get(target);
-    return {
-      target,
-      keys: keysToCallbacks ? [...keysToCallbacks.keys()] : [],
-    };
+    let keys = [];
+    if (keysToCallbacks) {
+      for (const [key, cbs] of keysToCallbacks) {
+        if (cbs.has(callback)) {
+          keys.push(key);
+        }
+      }
+    }
+    return { target, keys };
   });
 }
-
-const reactiveCache = new WeakMap<Target, WeakMap<Callback, Reactive>>();
+// Maps reactive objects to the underlying target
+export const targets = new WeakMap<Reactive<Target>, Target>();
+const reactiveCache = new WeakMap<Target, WeakMap<Callback, Reactive<Target>>>();
 /**
  * Creates a reactive proxy for an object. Reading data on the reactive object
  * subscribes to changes to the data. Writing data on the object will cause the
@@ -179,7 +190,7 @@ const reactiveCache = new WeakMap<Target, WeakMap<Callback, Reactive>>();
  * Subscriptions:
  * + Reading a property on an object will subscribe you to changes in the value
  *    of that property.
- * + Accessing an object keys (eg with Object.keys or with `for..in`) will
+ * + Accessing an object's keys (eg with Object.keys or with `for..in`) will
  *    subscribe you to the creation/deletion of keys. Checking the presence of a
  *    key on the object with 'in' has the same effect.
  * - getOwnPropertyDescriptor does not currently subscribe you to the property.
@@ -192,22 +203,19 @@ const reactiveCache = new WeakMap<Target, WeakMap<Callback, Reactive>>();
  *  reactive has changed
  * @returns a proxy that tracks changes to it
  */
-export function reactive<T extends Target>(
-  target: T,
-  callback: Callback = () => {}
-): Reactive<T> | NonReactive<T> {
+export function reactive<T extends Target>(target: T, callback: Callback = NO_CALLBACK): T {
   if (!canBeMadeReactive(target)) {
-    throw new Error(`Cannot make the given value reactive`);
+    throw new OwlError(`Cannot make the given value reactive`);
   }
-  if (SKIP in target) {
-    return target as NonReactive<T>;
+  if (skipped.has(target)) {
+    return target;
   }
-  const originalTarget = (target as Reactive)[TARGET];
-  if (originalTarget) {
-    return reactive(originalTarget, callback);
+  if (targets.has(target)) {
+    // target is reactive, create a reactive on the underlying object instead
+    return reactive(targets.get(target) as T, callback);
   }
   if (!reactiveCache.has(target)) {
-    reactiveCache.set(target, new Map());
+    reactiveCache.set(target, new WeakMap());
   }
   const reactivesForTarget = reactiveCache.get(target)!;
   if (!reactivesForTarget.has(callback)) {
@@ -217,6 +225,7 @@ export function reactive<T extends Target>(
       : basicProxyHandler<T>(callback);
     const proxy = new Proxy(target, handler as ProxyHandler<T>) as Reactive<T>;
     reactivesForTarget.set(callback, proxy);
+    targets.set(proxy, target);
   }
   return reactivesForTarget.get(callback) as Reactive<T>;
 }
@@ -228,29 +237,29 @@ export function reactive<T extends Target>(
  */
 function basicProxyHandler<T extends Target>(callback: Callback): ProxyHandler<T> {
   return {
-    get(target: any, key: PropertyKey, proxy: Reactive<T>) {
-      if (key === TARGET) {
-        return target;
-      }
+    get(target, key, receiver) {
       // non-writable non-configurable properties cannot be made reactive
       const desc = Object.getOwnPropertyDescriptor(target, key);
       if (desc && !desc.writable && !desc.configurable) {
-        return Reflect.get(target, key, proxy);
+        return Reflect.get(target, key, receiver);
       }
       observeTargetKey(target, key, callback);
-      return possiblyReactive(Reflect.get(target, key, proxy), callback);
+      return possiblyReactive(Reflect.get(target, key, receiver), callback);
     },
-    set(target, key, value, proxy) {
-      const isNewKey = !objectHasOwnProperty.call(target, key);
-      const originalValue = Reflect.get(target, key, proxy);
-      const ret = Reflect.set(target, key, value, proxy);
-      if (isNewKey) {
+    set(target, key, value, receiver) {
+      const hadKey = objectHasOwnProperty.call(target, key);
+      const originalValue = Reflect.get(target, key, receiver);
+      const ret = Reflect.set(target, key, value, receiver);
+      if (!hadKey && objectHasOwnProperty.call(target, key)) {
         notifyReactives(target, KEYCHANGES);
       }
       // While Array length may trigger the set trap, it's not actually set by this
       // method but is updated behind the scenes, and the trap is not called with the
       // new value. We disable the "same-value-optimization" for it because of that.
-      if (originalValue !== value || (Array.isArray(target) && key === "length")) {
+      if (
+        originalValue !== Reflect.get(target, key, receiver) ||
+        (key === "length" && Array.isArray(target))
+      ) {
         notifyReactives(target, key);
       }
       return ret;
@@ -443,10 +452,8 @@ function collectionsProxyHandler<T extends Collection>(
   // property is read.
   const specialHandlers = rawTypeToFuncHandlers[targetRawType](target, callback);
   return Object.assign(basicProxyHandler(callback), {
+    // FIXME: probably broken when part of prototype chain since we ignore the receiver
     get(target: any, key: PropertyKey) {
-      if (key === TARGET) {
-        return target;
-      }
       if (objectHasOwnProperty.call(specialHandlers, key)) {
         return (specialHandlers as any)[key];
       }

src/runtime/scheduler.ts

@@ -32,7 +32,7 @@ export class Scheduler {
       let renders = this.delayedRenders;
       this.delayedRenders = [];
       for (let f of renders) {
-        if (f.root && f.node.status !== STATUS.DESTROYED) {
+        if (f.root && f.node.status !== STATUS.DESTROYED && f.node.fiber === f) {
           f.render();
         }
       }

src/runtime/template_helpers.ts

@@ -0,0 +1,249 @@
+import { BDom, multi, text, toggler, createCatcher } from "./blockdom";
+import { Markup } from "./utils";
+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 type { ComponentNode } from "./component_node";
+
+const ObjectCreate = Object.create;
+/**
+ * This file contains utility functions that will be injected in each template,
+ * to perform various useful tasks in the compiled code.
+ */
+
+function withDefault(value: any, defaultValue: any): any {
+  return value === undefined || value === null || value === false ? defaultValue : value;
+}
+
+function callSlot(
+  ctx: any,
+  parent: any,
+  key: string,
+  name: string,
+  dynamic: boolean,
+  extra: any,
+  defaultContent?: (ctx: any, node: any, key: string) => BDom
+): BDom {
+  key = key + "__slot_" + name;
+  const slots = ctx.props.slots || {};
+  const { __render, __ctx, __scope } = slots[name] || {};
+  const slotScope = ObjectCreate(__ctx || {});
+  if (__scope) {
+    slotScope[__scope] = extra;
+  }
+  const slotBDom = __render ? __render(slotScope, parent, key) : null;
+  if (defaultContent) {
+    let child1: BDom | undefined = undefined;
+    let child2: BDom | undefined = undefined;
+    if (slotBDom) {
+      child1 = dynamic ? toggler(name, slotBDom) : slotBDom;
+    } else {
+      child2 = defaultContent(ctx, parent, key);
+    }
+    return multi([child1, child2]);
+  }
+  return slotBDom || text("");
+}
+
+function capture(ctx: any): any {
+  const result = ObjectCreate(ctx);
+  for (let k in ctx) {
+    result[k] = ctx[k];
+  }
+  return result;
+}
+
+function withKey(elem: any, k: string) {
+  elem.key = k;
+  return elem;
+}
+
+function prepareList(collection: any): [any[], any[], number, any[]] {
+  let keys: any[];
+  let values: any[];
+
+  if (Array.isArray(collection)) {
+    keys = collection;
+    values = collection;
+  } else if (collection) {
+    values = Object.keys(collection);
+    keys = Object.values(collection);
+  } else {
+    throw new OwlError("Invalid loop expression");
+  }
+  const n = values.length;
+  return [keys, values, n, new Array(n)];
+}
+
+const isBoundary = Symbol("isBoundary");
+
+function setContextValue(ctx: { [key: string]: any }, key: string, value: any): void {
+  const ctx0 = ctx;
+  while (!ctx.hasOwnProperty(key) && !ctx.hasOwnProperty(isBoundary)) {
+    const newCtx = ctx.__proto__;
+    if (!newCtx) {
+      ctx = ctx0;
+      break;
+    }
+    ctx = newCtx;
+  }
+  ctx[key] = value;
+}
+
+function toNumber(val: string): number | string {
+  const n = parseFloat(val);
+  return isNaN(n) ? val : n;
+}
+
+function shallowEqual(l1: any[], l2: any[]): boolean {
+  for (let i = 0, l = l1.length; i < l; i++) {
+    if (l1[i] !== l2[i]) {
+      return false;
+    }
+  }
+  return true;
+}
+
+class LazyValue {
+  fn: any;
+  ctx: any;
+  component: any;
+  node: any;
+  key: any;
+
+  constructor(fn: any, ctx: any, component: any, node: any, key: any) {
+    this.fn = fn;
+    this.ctx = capture(ctx);
+    this.component = component;
+    this.node = node;
+    this.key = key;
+  }
+
+  evaluate(): any {
+    return this.fn.call(this.component, this.ctx, this.node, this.key);
+  }
+
+  toString() {
+    return this.evaluate().toString();
+  }
+}
+
+/*
+ * Safely outputs `value` as a block depending on the nature of `value`
+ */
+export function safeOutput(value: any, defaultValue?: any): ReturnType<typeof toggler> {
+  if (value === undefined) {
+    return defaultValue ? toggler("default", defaultValue) : toggler("undefined", text(""));
+  }
+  let safeKey;
+  let block;
+  switch (typeof value) {
+    case "object":
+      if (value instanceof Markup) {
+        safeKey = `string_safe`;
+        block = html(value as string);
+      } else if (value instanceof LazyValue) {
+        safeKey = `lazy_value`;
+        block = value.evaluate();
+      } else if (value instanceof String) {
+        safeKey = "string_unsafe";
+        block = text(value);
+      } else {
+        // Assuming it is a block
+        safeKey = "block_safe";
+        block = value;
+      }
+      break;
+    case "string":
+      safeKey = "string_unsafe";
+      block = text(value);
+      break;
+    default:
+      safeKey = "string_unsafe";
+      block = text(String(value));
+  }
+  return toggler(safeKey, block);
+}
+
+/**
+ * Validate the component props (or next props) against the (static) props
+ * description.  This is potentially an expensive operation: it may needs to
+ * visit recursively the props and all the children to check if they are valid.
+ * This is why it is only done in 'dev' mode.
+ */
+export function validateProps<P>(name: string | ComponentConstructor<P>, props: P, comp?: any) {
+  const ComponentClass =
+    typeof name !== "string"
+      ? name
+      : (comp.constructor.components[name] as ComponentConstructor<P> | undefined);
+
+  if (!ComponentClass) {
+    // this is an error, wrong component. We silently return here instead so the
+    // error is triggered by the usual path ('component' function)
+    return;
+  }
+
+  const schema = ComponentClass.props;
+  if (!schema) {
+    if (comp.__owl__.app.warnIfNoStaticProps) {
+      console.warn(`Component '${ComponentClass.name}' does not have a static props description`);
+    }
+    return;
+  }
+  const defaultProps = ComponentClass.defaultProps;
+  if (defaultProps) {
+    let isMandatory = (name: string) =>
+      Array.isArray(schema)
+        ? schema.includes(name)
+        : name in schema && !("*" in schema) && !isOptional(schema[name]);
+    for (let p in defaultProps) {
+      if (isMandatory(p)) {
+        throw new OwlError(
+          `A default value cannot be defined for a mandatory prop (name: '${p}', component: ${ComponentClass.name})`
+        );
+      }
+    }
+  }
+
+  const errors = validateSchema(props, schema);
+  if (errors.length) {
+    throw new OwlError(
+      `Invalid props for component '${ComponentClass.name}': ` + errors.join(", ")
+    );
+  }
+}
+
+function makeRefWrapper(node: ComponentNode) {
+  let refNames: Set<String> = new Set();
+  return (name: string, fn: Function) => {
+    if (refNames.has(name)) {
+      throw new OwlError(
+        `Cannot set the same ref more than once in the same component, ref "${name}" was set multiple times in ${node.name}`
+      );
+    }
+    refNames.add(name);
+    return fn;
+  };
+}
+
+export const helpers = {
+  withDefault,
+  zero: Symbol("zero"),
+  isBoundary,
+  callSlot,
+  capture,
+  withKey,
+  prepareList,
+  setContextValue,
+  shallowEqual,
+  toNumber,
+  validateProps,
+  LazyValue,
+  safeOutput,
+  createCatcher,
+  markRaw,
+  OwlError,
+  makeRefWrapper,
+};

src/runtime/template_set.ts

@@ -1,12 +1,11 @@
-import { createBlock, html, list, multi, text, toggler, comment } from "../blockdom";
-import { compile, Template } from "../compiler";
-import { markRaw } from "../reactivity";
-import { Portal } from "../portal";
-import { component, getCurrent } from "../component/component_node";
+import { compile, Template, TemplateFunction } from "../compiler";
+import { comment, createBlock, html, list, multi, text, toggler } from "./blockdom";
+import { getCurrent } from "./component_node";
+import { Portal, portalTemplate } from "./portal";
 import { helpers } from "./template_helpers";
-import { globalTemplates } from "../utils";
+import { OwlError } from "./error_handling";
 
-const bdom = { text, createBlock, list, multi, html, toggler, component, comment };
+const bdom = { text, createBlock, list, multi, html, toggler, comment };
 
 function parseXML(xml: string): Document {
   const parser = new DOMParser();
@@ -33,27 +32,11 @@ function parseXML(xml: string): Document {
         }
       }
     }
-    throw new Error(msg);
+    throw new OwlError(msg);
   }
   return doc;
 }
 
-/**
- * Returns the helpers object that will be injected in each template closure
- * function
- */
-function makeHelpers(getTemplate: (name: string) => Template): any {
-  return Object.assign({}, helpers, {
-    Portal,
-    markRaw,
-    getTemplate,
-    call: (owner: any, subTemplate: string, ctx: any, parent: any, key: any) => {
-      const template = getTemplate(subTemplate);
-      return toggler(subTemplate, template.call(owner, ctx, parent, key));
-    },
-  });
-}
-
 export interface TemplateSetConfig {
   dev?: boolean;
   translatableAttributes?: string[];
@@ -62,12 +45,15 @@ export interface TemplateSetConfig {
 }
 
 export class TemplateSet {
+  static registerTemplate(name: string, fn: TemplateFunction) {
+    globalTemplates[name] = fn;
+  }
   dev: boolean;
   rawTemplates: typeof globalTemplates = Object.create(globalTemplates);
   templates: { [name: string]: Template } = {};
   translateFn?: (s: string) => string;
   translatableAttributes?: string[];
-  helpers: any;
+  Portal = Portal;
 
   constructor(config: TemplateSetConfig = {}) {
     this.dev = config.dev || false;
@@ -76,21 +62,27 @@ export class TemplateSet {
     if (config.templates) {
       this.addTemplates(config.templates);
     }
-    this.helpers = makeHelpers(this.getTemplate.bind(this));
   }
 
-  addTemplate(
-    name: string,
-    template: string | Element,
-    options: { allowDuplicate?: boolean } = {}
-  ) {
-    if (name in this.rawTemplates && !options.allowDuplicate) {
-      throw new Error(`Template ${name} already defined`);
+  addTemplate(name: string, template: string | Element) {
+    if (name in this.rawTemplates) {
+      const rawTemplate = this.rawTemplates[name];
+      const currentAsString =
+        typeof rawTemplate === "string"
+          ? rawTemplate
+          : rawTemplate instanceof Element
+          ? rawTemplate.outerHTML
+          : rawTemplate.toString();
+      const newAsString = typeof template === "string" ? template : template.outerHTML;
+      if (currentAsString === newAsString) {
+        return;
+      }
+      throw new OwlError(`Template ${name} already defined with different content`);
     }
     this.rawTemplates[name] = template;
   }
 
-  addTemplates(xml: string | Document, options: { allowDuplicate?: boolean } = {}) {
+  addTemplates(xml: string | Document) {
     if (!xml) {
       // empty string
       return;
@@ -98,7 +90,7 @@ export class TemplateSet {
     xml = xml instanceof Document ? xml : parseXML(xml);
     for (const template of xml.querySelectorAll("[t-name]")) {
       const name = template.getAttribute("t-name")!;
-      this.addTemplate(name, template, options);
+      this.addTemplate(name, template);
     }
   }
 
@@ -111,27 +103,44 @@ export class TemplateSet {
           const componentName = getCurrent().component.constructor.name;
           extraInfo = ` (for component "${componentName}")`;
         } catch {}
-        throw new Error(`Missing template: "${name}"${extraInfo}`);
+        throw new OwlError(`Missing template: "${name}"${extraInfo}`);
       }
-      const templateFn = this._compileTemplate(name, rawTemplate);
+      const isFn = typeof rawTemplate === "function" && !(rawTemplate instanceof Element);
+      const templateFn = isFn ? rawTemplate : this._compileTemplate(name, rawTemplate);
       // first add a function to lazily get the template, in case there is a
       // recursive call to the template name
       const templates = this.templates;
       this.templates[name] = function (context, parent) {
         return templates[name].call(this, context, parent);
       };
-      const template = templateFn(bdom, this.helpers);
+      const template = templateFn(this, bdom, helpers);
       this.templates[name] = template;
     }
     return this.templates[name];
   }
 
-  _compileTemplate(name: string, template: string | Element) {
-    return compile(template, {
-      name,
-      dev: this.dev,
-      translateFn: this.translateFn,
-      translatableAttributes: this.translatableAttributes,
-    });
+  _compileTemplate(name: string, template: string | Element): ReturnType<typeof compile> {
+    throw new OwlError(`Unable to compile a template. Please use owl full build instead`);
+  }
+
+  callTemplate(owner: any, subTemplate: string, ctx: any, parent: any, key: any): any {
+    const template = this.getTemplate(subTemplate);
+    return toggler(subTemplate, template.call(owner, ctx, parent, key));
   }
 }
+
+// -----------------------------------------------------------------------------
+//  xml tag helper
+// -----------------------------------------------------------------------------
+export const globalTemplates: { [key: string]: string | Element | TemplateFunction } = {};
+
+export function xml(...args: Parameters<typeof String.raw>) {
+  const name = `__template__${xml.nextId++}`;
+  const value = String.raw(...args);
+  globalTemplates[name] = value;
+  return name;
+}
+
+xml.nextId = 1;
+
+TemplateSet.registerTemplate("__portal__", portalTemplate);

src/runtime/utils.ts

@@ -1,3 +1,4 @@
+import { OwlError } from "./error_handling";
 export type Callback = () => void;
 
 /**
@@ -26,13 +27,34 @@ export function batched(callback: Callback): Callback {
   };
 }
 
-export function validateTarget(target: HTMLElement) {
-  if (!(target instanceof HTMLElement)) {
-    throw new Error("Cannot mount component: the target is not a valid DOM element");
+/**
+ * Determine whether the given element is contained in its ownerDocument:
+ * either directly or with a shadow root in between.
+ */
+export function inOwnerDocument(el?: HTMLElement) {
+  if (!el) {
+    return false;
   }
-  if (!document.body.contains(target)) {
-    throw new Error("Cannot mount a component on a detached dom node");
+  if (el.ownerDocument.contains(el)) {
+    return true;
   }
+  const rootNode = el.getRootNode();
+  return rootNode instanceof ShadowRoot && el.ownerDocument.contains(rootNode.host);
+}
+
+export function validateTarget(target: HTMLElement | ShadowRoot) {
+  // Get the document and HTMLElement corresponding to the target to allow mounting in iframes
+  const document = target && target.ownerDocument;
+  if (document) {
+    const HTMLElement = document.defaultView!.HTMLElement;
+    if (target instanceof HTMLElement || target instanceof ShadowRoot) {
+      if (!document.body.contains(target instanceof HTMLElement ? target : target.host)) {
+        throw new OwlError("Cannot mount a component on a detached dom node");
+      }
+      return;
+    }
+  }
+  throw new OwlError("Cannot mount component: the target is not a valid DOM element");
 }
 
 export class EventBus extends EventTarget {
@@ -54,7 +76,7 @@ export function whenReady(fn?: any): Promise<void> {
 export async function loadFile(url: string): Promise<string> {
   const result = await fetch(url);
   if (!result.ok) {
-    throw new Error("Error while fetching xml templates");
+    throw new OwlError("Error while fetching xml templates");
   }
   return await result.text();
 }
@@ -73,17 +95,3 @@ export class Markup extends String {}
 export function markup(value: any) {
   return new Markup(value);
 }
-
-// -----------------------------------------------------------------------------
-//  xml tag helper
-// -----------------------------------------------------------------------------
-export const globalTemplates: { [key: string]: string | Element } = {};
-
-export function xml(...args: Parameters<typeof String.raw>) {
-  const name = `__template__${xml.nextId++}`;
-  const value = String.raw(...args);
-  globalTemplates[name] = value;
-  return name;
-}
-
-xml.nextId = 1;

src/runtime/validation.ts

@@ -0,0 +1,183 @@
+import { OwlError } from "./error_handling";
+import { toRaw } from "./reactivity";
+
+type BaseType =
+  | typeof String
+  | typeof Boolean
+  | typeof Number
+  | typeof Date
+  | typeof Object
+  | typeof Array
+  | true
+  | "*";
+
+interface TypeInfo {
+  type?: TypeDescription;
+  optional?: boolean;
+  validate?: Function;
+  shape?: Schema;
+  element?: TypeDescription;
+  values?: TypeDescription;
+}
+
+type ValueType = { value: any };
+
+type TypeDescription = BaseType | TypeInfo | ValueType | TypeDescription[];
+type SimplifiedSchema = string[];
+type NormalizedSchema = { [key: string]: TypeDescription };
+export type Schema = SimplifiedSchema | NormalizedSchema;
+
+// -----------------------------------------------------------------------------
+// helpers
+// -----------------------------------------------------------------------------
+const isUnionType = (t: TypeDescription): t is TypeDescription[] => Array.isArray(t);
+const isBaseType = (t: TypeDescription): t is BaseType => typeof t !== "object";
+const isValueType = (t: TypeDescription): t is ValueType =>
+  typeof t === "object" && t && "value" in t;
+
+export function isOptional(t: TypeDescription): Boolean {
+  return typeof t === "object" && "optional" in t ? t.optional || false : false;
+}
+
+function describeType(type: BaseType): string {
+  return type === "*" || type === true ? "value" : type.name.toLowerCase();
+}
+
+function describe(info: TypeDescription): string {
+  if (isBaseType(info)) {
+    return describeType(info);
+  } else if (isUnionType(info)) {
+    return info.map(describe).join(" or ");
+  } else if (isValueType(info)) {
+    return String(info.value);
+  }
+  if ("element" in info) {
+    return `list of ${describe({ type: info.element, optional: false })}s`;
+  }
+  if ("shape" in (info as TypeInfo)) {
+    return `object`;
+  }
+  return describe(info.type || "*");
+}
+
+function toSchema(spec: SimplifiedSchema): NormalizedSchema {
+  return Object.fromEntries(
+    spec.map((e) =>
+      e.endsWith("?") ? [e.slice(0, -1), { optional: true }] : [e, { type: "*", optional: false }]
+    )
+  );
+}
+
+/**
+ * Main validate function
+ */
+export function validate(obj: { [key: string]: any }, spec: Schema) {
+  let errors = validateSchema(obj, spec);
+  if (errors.length) {
+    throw new OwlError("Invalid object: " + errors.join(", "));
+  }
+}
+
+/**
+ * Helper validate function, to get the list of errors. useful if one want to
+ * manipulate the errors without parsing an error object
+ */
+export function validateSchema(obj: { [key: string]: any }, schema: Schema): string[] {
+  if (Array.isArray(schema)) {
+    schema = toSchema(schema);
+  }
+  obj = toRaw(obj);
+  let errors = [];
+  // check if each value in obj has correct shape
+  for (let key in obj) {
+    if (key in schema) {
+      let result = validateType(key, obj[key], schema[key]);
+      if (result) {
+        errors.push(result);
+      }
+    } else if (!("*" in schema)) {
+      errors.push(`unknown key '${key}'`);
+    }
+  }
+  // check that all specified keys are defined in obj
+  for (let key in schema) {
+    const spec = schema[key];
+    if (key !== "*" && !isOptional(spec) && !(key in obj)) {
+      const isObj = typeof spec === "object" && !Array.isArray(spec);
+      const isAny = spec === "*" || (isObj && "type" in spec ? spec.type === "*" : isObj);
+      let detail = isAny ? "" : ` (should be a ${describe(spec)})`;
+      errors.push(`'${key}' is missing${detail}`);
+    }
+  }
+  return errors;
+}
+
+function validateBaseType(key: string, value: any, type: BaseType): string | null {
+  if (typeof type === "function") {
+    if (typeof value === "object") {
+      if (!(value instanceof type)) {
+        return `'${key}' is not a ${describeType(type)}`;
+      }
+    } else if (typeof value !== type.name.toLowerCase()) {
+      return `'${key}' is not a ${describeType(type)}`;
+    }
+  }
+  return null;
+}
+
+function validateArrayType(key: string, value: any, descr: TypeDescription): string | null {
+  if (!Array.isArray(value)) {
+    return `'${key}' is not a list of ${describe(descr)}s`;
+  }
+  for (let i = 0; i < value.length; i++) {
+    const error = validateType(`${key}[${i}]`, value[i], descr);
+    if (error) {
+      return error;
+    }
+  }
+  return null;
+}
+
+export function validateType(key: string, value: any, descr: TypeDescription): string | null {
+  if (value === undefined) {
+    return isOptional(descr) ? null : `'${key}' is undefined (should be a ${describe(descr)})`;
+  } else if (isBaseType(descr)) {
+    return validateBaseType(key, value, descr);
+  } else if (isValueType(descr)) {
+    return value === descr.value ? null : `'${key}' is not equal to '${descr.value}'`;
+  } else if (isUnionType(descr)) {
+    let validDescr = descr.find((p) => !validateType(key, value, p));
+    return validDescr ? null : `'${key}' is not a ${describe(descr)}`;
+  }
+  let result: string | null = null;
+  if ("element" in descr) {
+    result = validateArrayType(key, value, descr.element!);
+  } else if ("shape" in descr) {
+    if (typeof value !== "object" || Array.isArray(value)) {
+      result = `'${key}' is not an object`;
+    } else {
+      const errors = validateSchema(value, descr.shape!);
+      if (errors.length) {
+        result = `'${key}' doesn't have the correct shape (${errors.join(", ")})`;
+      }
+    }
+  } else if ("values" in descr) {
+    if (typeof value !== "object" || Array.isArray(value)) {
+      result = `'${key}' is not an object`;
+    } else {
+      const errors = Object.entries(value)
+        .map(([key, value]) => validateType(key, value, descr.values!))
+        .filter(Boolean);
+      if (errors.length) {
+        result = `some of the values in '${key}' are invalid (${errors.join(", ")})`;
+      }
+    }
+  }
+  if ("type" in descr && !result) {
+    result = validateType(key, value, descr.type!);
+  }
+  if ("validate" in descr && !result) {
+    result = !descr.validate!(value) ? `'${key}' is not valid` : null;
+  }
+  return result;
+}

src/version.ts

@@ -0,0 +1,2 @@
+// do not modify manually. This file is generated by the release script.
+export const version = "2.1.1";

tests/__snapshots__/reactivity.test.ts.snap

@@ -47,16 +47,17 @@ exports[`Reactivity: useState concurrent renderings 3`] = `
 `;
 
 exports[`Reactivity: useState destroyed component before being mounted is inactive 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
     let b2;
     if (ctx['state'].flag) {
-      b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+      b2 = comp1({}, key + \`__1\`, node, this, null);
     }
     return block1([], [b2]);
   }
@@ -64,9 +65,9 @@ exports[`Reactivity: useState destroyed component before being mounted is inacti
 `;
 
 exports[`Reactivity: useState destroyed component before being mounted is inactive 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -78,16 +79,17 @@ exports[`Reactivity: useState destroyed component before being mounted is inacti
 `;
 
 exports[`Reactivity: useState destroyed component is inactive 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
     let b2;
     if (ctx['state'].flag) {
-      b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+      b2 = comp1({}, key + \`__1\`, node, this, null);
     }
     return block1([], [b2]);
   }
@@ -95,9 +97,9 @@ exports[`Reactivity: useState destroyed component is inactive 1`] = `
 `;
 
 exports[`Reactivity: useState destroyed component is inactive 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -109,9 +111,9 @@ exports[`Reactivity: useState destroyed component is inactive 2`] = `
 `;
 
 exports[`Reactivity: useState one components can subscribe twice to same context 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/><block-text-1/></div>\`);
   
@@ -124,14 +126,15 @@ exports[`Reactivity: useState one components can subscribe twice to same context
 `;
 
 exports[`Reactivity: useState parent and children subscribed to same context 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/><block-text-0/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
     let txt1 = ctx['contextObj'].b;
     return block1([txt1], [b2]);
   }
@@ -139,9 +142,9 @@ exports[`Reactivity: useState parent and children subscribed to same context 1`]
 `;
 
 exports[`Reactivity: useState parent and children subscribed to same context 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -216,24 +219,26 @@ exports[`Reactivity: useState several nodes on different level use same context
 `;
 
 exports[`Reactivity: useState two components are updated in parallel 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
+  const comp2 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
-    const b3 = component(\`Child\`, {}, key + \`__2\`, node, ctx);
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
+    const b3 = comp2({}, key + \`__2\`, node, this, null);
     return block1([], [b2, b3]);
   }
 }"
 `;
 
 exports[`Reactivity: useState two components are updated in parallel 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -245,24 +250,26 @@ exports[`Reactivity: useState two components are updated in parallel 2`] = `
 `;
 
 exports[`Reactivity: useState two components can subscribe to same context 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
+  const comp2 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
-    const b3 = component(\`Child\`, {}, key + \`__2\`, node, ctx);
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
+    const b3 = comp2({}, key + \`__2\`, node, this, null);
     return block1([], [b2, b3]);
   }
 }"
 `;
 
 exports[`Reactivity: useState two components can subscribe to same context 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -274,24 +281,26 @@ exports[`Reactivity: useState two components can subscribe to same context 2`] =
 `;
 
 exports[`Reactivity: useState two independent components on different levels are updated in parallel 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
+  const comp2 = app.createComponent(\`Parent\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
-    const b3 = component(\`Parent\`, {}, key + \`__2\`, node, ctx);
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
+    const b3 = comp2({}, key + \`__2\`, node, this, null);
     return block1([], [b2, b3]);
   }
 }"
 `;
 
 exports[`Reactivity: useState two independent components on different levels are updated in parallel 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
   
@@ -303,23 +312,24 @@ exports[`Reactivity: useState two independent components on different levels are
 `;
 
 exports[`Reactivity: useState two independent components on different levels are updated in parallel 3`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const comp1 = app.createComponent(\`Child\`, true, false, false, []);
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const b2 = component(\`Child\`, {}, key + \`__1\`, node, ctx);
+    const b2 = comp1({}, key + \`__1\`, node, this, null);
     return block1([], [b2]);
   }
 }"
 `;
 
 exports[`Reactivity: useState useContext=useState hook is reactive, for one component 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   
@@ -331,10 +341,11 @@ exports[`Reactivity: useState useContext=useState hook is reactive, for one comp
 `;
 
 exports[`Reactivity: useState useless atoms should be deleted 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { prepareList, withKey } = helpers;
+  const comp1 = app.createComponent(\`Quantity\`, true, false, false, [\\"id\\"]);
   
   let block1 = createBlock(\`<div><block-child-0/> Total: <block-text-0/> Count: <block-text-1/></div>\`);
   
@@ -344,7 +355,7 @@ exports[`Reactivity: useState useless atoms should be deleted 1`] = `
     for (let i1 = 0; i1 < l_block2; i1++) {
       ctx[\`id\`] = v_block2[i1];
       const key1 = ctx['id'];
-      c_block2[i1] = withKey(component(\`Quantity\`, {id: ctx['id']}, key + \`__1__\${key1}\`, node, ctx), key1);
+      c_block2[i1] = withKey(comp1({id: ctx['id']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
     ctx = ctx.__proto__;
     const b2 = list(c_block2);
@@ -356,9 +367,9 @@ exports[`Reactivity: useState useless atoms should be deleted 1`] = `
 `;
 
 exports[`Reactivity: useState useless atoms should be deleted 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   
@@ -370,9 +381,9 @@ exports[`Reactivity: useState useless atoms should be deleted 2`] = `
 `;
 
 exports[`Reactivity: useState very simple use, with initial value 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   

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

@@ -1,9 +1,9 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`app App supports env with getters/setters 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/> <block-text-1/></div>\`);
   
@@ -16,9 +16,9 @@ exports[`app App supports env with getters/setters 1`] = `
 `;
 
 exports[`app can configure an app with props 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-text-0/></div>\`);
   
@@ -29,10 +29,23 @@ exports[`app can configure an app with props 1`] = `
 }"
 `;
 
-exports[`app destroy remove the widget from the DOM 1`] = `
-"function anonymous(bdom, helpers
+exports[`app can mount app in an iframe 1`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div class=\\"my-div\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`app destroy remove the widget from the DOM 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div/>\`);
   
@@ -41,3 +54,17 @@ exports[`app destroy remove the widget from the DOM 1`] = `
   }
 }"
 `;
+
+exports[`app warnIfNoStaticProps works as expected 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div><block-text-0/></div>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let txt1 = ctx['message'];
+    return block1([txt1]);
+  }
+}"
+`;

tests/app/app.test.ts

@@ -1,5 +1,5 @@
-import { App, Component, xml } from "../../src";
-import { status } from "../../src/component/status";
+import { App, Component, mount, xml } from "../../src";
+import { status } from "../../src/runtime/status";
 import { makeTestFixture, snapshotEverything, nextTick, elem } from "../helpers";
 
 let fixture: HTMLElement;
@@ -59,4 +59,39 @@ describe("app", () => {
     await app.mount(fixture);
     expect(fixture.innerHTML).toBe("<div>333</div>");
   });
+
+  test("warnIfNoStaticProps works as expected", async () => {
+    let originalconsoleWarn = console.warn;
+    let mockConsoleWarn = jest.fn(() => {});
+    console.warn = mockConsoleWarn;
+
+    class Root extends Component {
+      static template = xml`<div t-esc="message"/>`;
+    }
+
+    await mount(Root, fixture, { test: true, props: { messge: "hey" }, warnIfNoStaticProps: true });
+
+    console.warn = originalconsoleWarn;
+    expect(mockConsoleWarn).toBeCalledWith(
+      "Component 'Root' does not have a static props description"
+    );
+  });
+
+  test("can mount app in an iframe", async () => {
+    class SomeComponent extends Component {
+      static template = xml`<div class="my-div"/>`;
+    }
+
+    const iframe = document.createElement("iframe");
+    fixture.appendChild(iframe);
+    const app = new App(SomeComponent);
+    const iframeDoc = iframe.contentDocument!;
+    const comp = await app.mount(iframeDoc.body);
+    const div = iframeDoc.querySelector(".my-div");
+    expect(div).not.toBe(null);
+    expect(iframeDoc.contains(div)).toBe(true);
+    app.destroy();
+    expect(iframeDoc.contains(div)).toBe(false);
+    expect(status(comp)).toBe("destroyed");
+  });
 });

tests/blockdom/block.test.ts

@@ -1,4 +1,4 @@
-import { createBlock, mount, patch, remove, text } from "../../src/blockdom";
+import { createBlock, mount, patch, remove, text } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/block_attributes.test.ts

@@ -1,4 +1,4 @@
-import { mount, patch, createBlock } from "../../src/blockdom";
+import { mount, patch, createBlock } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------
@@ -145,59 +145,3 @@ test("class attribute (with a preexisting value", async () => {
   patch(tree, block([""]));
   expect(fixture.innerHTML).toBe(`<div class="tomato"></div>`);
 });
-
-describe("properties", () => {
-  test("input with value attribute", () => {
-    // render input with initial value
-    const block = createBlock(`<input block-attribute-0="value"/>`);
-
-    const tree = block(["zucchini"]);
-    mount(tree, fixture);
-    // const bnode1 = renderToBdom(template, { v: "zucchini" });
-    // const fixture = makeTestFixture();
-    // mount(bnode1, fixture);
-    const input = fixture.querySelector("input")!;
-    expect(input.value).toBe("zucchini");
-
-    // change value manually in input, to simulate user input
-    input.value = "tomato";
-    expect(input.value).toBe("tomato");
-
-    // rerender with a different value, and patch actual dom, to check that
-    // input value was properly reset by owl
-    patch(tree, block(["potato"]));
-    expect(input.value).toBe("potato");
-  });
-
-  test("input with value attribute, and falsy value given", () => {
-    const block = createBlock(`<input block-attribute-0="value"/>`);
-
-    const tree = block([undefined]);
-    mount(tree, fixture);
-    const input = fixture.querySelector("input")!;
-    expect(input.value).toBe("");
-
-    patch(tree, block([null]));
-    expect(input.value).toBe("");
-
-    patch(tree, block([0]));
-    expect(input.value).toBe("0");
-
-    patch(tree, block([""]));
-    expect(input.value).toBe("");
-
-    patch(tree, block([false]));
-    expect(input.value).toBe("");
-  });
-
-  test("input type=checkbox with checked attribute", () => {
-    // render input with initial value
-    const block = createBlock(`<input type="checkbox" block-attribute-0="checked"/>`);
-
-    const tree = block([true]);
-    mount(tree, fixture);
-    expect(fixture.innerHTML).toBe(`<input type="checkbox">`);
-    const input = fixture.querySelector("input")!;
-    expect(input.checked).toBe(true);
-  });
-});

tests/blockdom/block_event_handling.test.ts

@@ -1,4 +1,4 @@
-import { mount, createBlock, multi, config, patch } from "../../src/blockdom";
+import { mount, createBlock, multi, config, patch } from "../../src/runtime/blockdom";
 // import { defaultHandler, setupMainHandler } from "../../src/bdom/block";
 import { makeTestFixture } from "./helpers";
 

tests/blockdom/block_properties.test.ts

@@ -0,0 +1,70 @@
+import { mount, patch, createBlock } from "../../src/runtime/blockdom";
+import { makeTestFixture } from "./helpers";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+let fixture: HTMLElement;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+});
+
+afterEach(() => {
+  fixture.remove();
+});
+
+test("input with value property", () => {
+  // render input with initial value
+  const block = createBlock(`<input block-property-0="value"/>`);
+
+  const tree = block(["zucchini"]);
+  mount(tree, fixture);
+  // const bnode1 = renderToBdom(template, { v: "zucchini" });
+  // const fixture = makeTestFixture();
+  // mount(bnode1, fixture);
+  const input = fixture.querySelector("input")!;
+  expect(input.value).toBe("zucchini");
+
+  // change value manually in input, to simulate user input
+  input.value = "tomato";
+  expect(input.value).toBe("tomato");
+
+  // rerender with a different value, and patch actual dom, to check that
+  // input value was properly reset by owl
+  patch(tree, block(["potato"]));
+  expect(input.value).toBe("potato");
+});
+
+test("input with value property, and falsy value given", () => {
+  const block = createBlock(`<input block-property-0="value"/>`);
+
+  const tree = block([undefined]);
+  mount(tree, fixture);
+  const input = fixture.querySelector("input")!;
+  expect(input.value).toBe("");
+
+  patch(tree, block([null]));
+  expect(input.value).toBe("");
+
+  patch(tree, block([0]));
+  expect(input.value).toBe("0");
+
+  patch(tree, block([""]));
+  expect(input.value).toBe("");
+
+  patch(tree, block([false]));
+  expect(input.value).toBe("");
+});
+
+test("input type=checkbox with checked property", () => {
+  // render input with initial value
+  const block = createBlock(`<input type="checkbox" block-property-0="checked"/>`);
+
+  const tree = block([true]);
+  mount(tree, fixture);
+  expect(fixture.innerHTML).toBe(`<input type="checkbox">`);
+  const input = fixture.querySelector("input")!;
+  expect(input.checked).toBe(true);
+});

tests/blockdom/block_refs.test.ts

@@ -1,4 +1,4 @@
-import { createBlock, mount, patch, remove } from "../../src/blockdom";
+import { createBlock, mount, patch, remove } from "../../src/runtime/blockdom";
 import { logStep } from "../helpers";
 import { makeTestFixture } from "./helpers";
 

tests/blockdom/comment.test.ts

@@ -1,4 +1,4 @@
-import { comment, mount } from "../../src/blockdom";
+import { comment, mount } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/event_catcher.test.ts

@@ -1,6 +1,6 @@
-import { config, createBlock, createCatcher, mount } from "../../src/blockdom";
+import { config, createBlock, createCatcher, mount } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
-import { mainEventHandler } from "../../src/component/handler";
+import { mainEventHandler } from "../../src/runtime/event_handling";
 
 //------------------------------------------------------------------------------
 // Setup and helpers

tests/blockdom/html.test.ts

@@ -1,4 +1,4 @@
-import { html, mount, patch, text } from "../../src/blockdom";
+import { html, mount, patch, text } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/list.test.ts

@@ -1,4 +1,13 @@
-import { list, mount, multi, patch, text, createBlock, VNode, withKey } from "../../src/blockdom";
+import {
+  list,
+  mount,
+  multi,
+  patch,
+  text,
+  createBlock,
+  VNode,
+  withKey,
+} from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/multi.test.ts

@@ -1,4 +1,4 @@
-import { mount, multi, patch, text, createBlock } from "../../src/blockdom";
+import { mount, multi, patch, text, createBlock } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/namespace.test.ts

@@ -1,4 +1,4 @@
-import { createBlock, mount } from "../../src/blockdom";
+import { createBlock, mount } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/remove_hook.test.ts

@@ -1,4 +1,4 @@
-import { createBlock, mount, multi, patch } from "../../src/blockdom";
+import { createBlock, mount, multi, patch } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/text.test.ts

@@ -1,4 +1,4 @@
-import { mount, patch, remove, text } from "../../src/blockdom";
+import { mount, patch, remove, text } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

tests/blockdom/toggler.test.ts

@@ -1,4 +1,4 @@
-import { createBlock, mount, patch, text, toggler } from "../../src/blockdom";
+import { createBlock, mount, patch, text, toggler } from "../../src/runtime/blockdom";
 import { makeTestFixture } from "./helpers";
 
 //------------------------------------------------------------------------------

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

@@ -1,9 +1,9 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`attributes changing a class with t-att-class (preexisting class 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"hoy\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -15,9 +15,9 @@ exports[`attributes changing a class with t-att-class (preexisting class 1`] = `
 `;
 
 exports[`attributes changing a class with t-att-class 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -28,24 +28,10 @@ exports[`attributes changing a class with t-att-class 1`] = `
 }"
 `;
 
-exports[`attributes changing an attribute with t-att- 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<div block-attribute-0=\\"value\\"/>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['v'];
-    return block1([attr1]);
-  }
-}"
-`;
-
 exports[`attributes class and t-att-class should combine together 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\" class=\\"hello\\"/>\`);
   
@@ -57,9 +43,9 @@ exports[`attributes class and t-att-class should combine together 1`] = `
 `;
 
 exports[`attributes class and t-attf-class with ternary operation 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"hello\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -71,9 +57,9 @@ exports[`attributes class and t-attf-class with ternary operation 1`] = `
 `;
 
 exports[`attributes dynamic attribute evaluating to 0 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -85,9 +71,9 @@ exports[`attributes dynamic attribute evaluating to 0 1`] = `
 `;
 
 exports[`attributes dynamic attribute falsy variable  1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -99,9 +85,9 @@ exports[`attributes dynamic attribute falsy variable  1`] = `
 `;
 
 exports[`attributes dynamic attribute with a dash 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"data-action-id\\"/>\`);
   
@@ -113,9 +99,9 @@ exports[`attributes dynamic attribute with a dash 1`] = `
 `;
 
 exports[`attributes dynamic attributes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -126,10 +112,24 @@ exports[`attributes dynamic attributes 1`] = `
 }"
 `;
 
-exports[`attributes dynamic class attribute 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes dynamic attributes with backticks 1`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = \`bar\`;
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes dynamic class attribute 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -141,9 +141,9 @@ exports[`attributes dynamic class attribute 1`] = `
 `;
 
 exports[`attributes dynamic class attribute evaluating to 0 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -154,10 +154,52 @@ exports[`attributes dynamic class attribute evaluating to 0 1`] = `
 }"
 `;
 
-exports[`attributes dynamic empty class attribute 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes dynamic class attribute that starts and ends with a space 1`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = ctx['c'];
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes dynamic class attribute which is only a space 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = ctx['c'];
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes dynamic class attribute with multiple consecutive spaces 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = ctx['c'];
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes dynamic empty class attribute 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -169,9 +211,9 @@ exports[`attributes dynamic empty class attribute 1`] = `
 `;
 
 exports[`attributes dynamic formatted attributes with a dash 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"aria-label\\"/>\`);
   
@@ -183,9 +225,9 @@ exports[`attributes dynamic formatted attributes with a dash 1`] = `
 `;
 
 exports[`attributes dynamic undefined class attribute 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -197,9 +239,9 @@ exports[`attributes dynamic undefined class attribute 1`] = `
 `;
 
 exports[`attributes dynamic undefined generic attribute 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"thing\\"/>\`);
   
@@ -211,9 +253,9 @@ exports[`attributes dynamic undefined generic attribute 1`] = `
 `;
 
 exports[`attributes fixed variable 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -225,9 +267,9 @@ exports[`attributes fixed variable 1`] = `
 `;
 
 exports[`attributes format expression 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -239,9 +281,9 @@ exports[`attributes format expression 1`] = `
 `;
 
 exports[`attributes format literal 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -253,9 +295,9 @@ exports[`attributes format literal 1`] = `
 `;
 
 exports[`attributes format multiple 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -267,9 +309,9 @@ exports[`attributes format multiple 1`] = `
 `;
 
 exports[`attributes format value 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
   
@@ -281,9 +323,9 @@ exports[`attributes format value 1`] = `
 `;
 
 exports[`attributes from object variables set previously 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { isBoundary, withDefault, setContextValue } = helpers;
   
   let block1 = createBlock(\`<div><span block-attribute-0=\\"class\\"/></div>\`);
@@ -299,9 +341,9 @@ exports[`attributes from object variables set previously 1`] = `
 `;
 
 exports[`attributes from variables set previously (no external node) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { isBoundary, withDefault, setContextValue } = helpers;
   
   let block1 = createBlock(\`<span block-attribute-0=\\"class\\"/>\`);
@@ -317,9 +359,9 @@ exports[`attributes from variables set previously (no external node) 1`] = `
 `;
 
 exports[`attributes from variables set previously 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { isBoundary, withDefault, setContextValue } = helpers;
   
   let block1 = createBlock(\`<div><span block-attribute-0=\\"class\\"/></div>\`);
@@ -335,9 +377,9 @@ exports[`attributes from variables set previously 1`] = `
 `;
 
 exports[`attributes object 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attributes=\\"0\\"/>\`);
   
@@ -349,9 +391,9 @@ exports[`attributes object 1`] = `
 `;
 
 exports[`attributes static attributes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div foo=\\"a\\" bar=\\"b\\" baz=\\"c\\"/>\`);
   
@@ -362,9 +404,9 @@ exports[`attributes static attributes 1`] = `
 `;
 
 exports[`attributes static attributes on void elements 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<img src=\\"/test.skip.jpg\\" alt=\\"Test\\"/>\`);
   
@@ -374,10 +416,36 @@ exports[`attributes static attributes on void elements 1`] = `
 }"
 `;
 
-exports[`attributes static attributes with dashes 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes static attributes with backslash or backtick 1`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div foo=\\"\\\\\\\\a\\" bar=\\"\\\\\\\\n\\" baz=\\"\\\\\`\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`attributes static attributes with backticks 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div foo=\\"\\\\\`bar\\\\\`\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`attributes static attributes with dashes 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div aria-label=\\"Close\\"/>\`);
   
@@ -387,10 +455,24 @@ exports[`attributes static attributes with dashes 1`] = `
 }"
 `;
 
-exports[`attributes t-att-class and class should combine together 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes string interpolation, alternate syntax 1`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"foo\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = \`b\${ctx['value']}r\`;
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes t-att-class and class should combine together 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"hello\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -402,9 +484,9 @@ exports[`attributes t-att-class and class should combine together 1`] = `
 `;
 
 exports[`attributes t-att-class with multiple classes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -416,9 +498,9 @@ exports[`attributes t-att-class with multiple classes 1`] = `
 `;
 
 exports[`attributes t-att-class with multiple classes 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -429,10 +511,24 @@ exports[`attributes t-att-class with multiple classes 2`] = `
 }"
 `;
 
-exports[`attributes t-att-class with multiple classes, some of which are duplicate 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes t-att-class with multiple classes 3`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = {'a  b  c':ctx['value']};
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes t-att-class with multiple classes, some of which are duplicate 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -444,9 +540,9 @@ exports[`attributes t-att-class with multiple classes, some of which are duplica
 `;
 
 exports[`attributes t-att-class with object 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"static\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -457,10 +553,38 @@ exports[`attributes t-att-class with object 1`] = `
 }"
 `;
 
-exports[`attributes t-attf-class 1`] = `
-"function anonymous(bdom, helpers
+exports[`attributes t-att-class with object 2`] = `
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = {' a ':ctx['value']};
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes t-att-class with object 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = {' ':ctx['value']};
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`attributes t-attf-class 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -472,9 +596,9 @@ exports[`attributes t-attf-class 1`] = `
 `;
 
 exports[`attributes t-attf-class should combine with class 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"hello\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -486,9 +610,9 @@ exports[`attributes t-attf-class should combine with class 1`] = `
 `;
 
 exports[`attributes t-attf-class with multiple classes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -500,9 +624,9 @@ exports[`attributes t-attf-class with multiple classes 1`] = `
 `;
 
 exports[`attributes t-attf-class with multiple classes separated by multiple spaces 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"/>\`);
   
@@ -514,9 +638,9 @@ exports[`attributes t-attf-class with multiple classes separated by multiple spa
 `;
 
 exports[`attributes tuple literal 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attributes=\\"0\\"/>\`);
   
@@ -528,9 +652,9 @@ exports[`attributes tuple literal 1`] = `
 `;
 
 exports[`attributes tuple variable 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attributes=\\"0\\"/>\`);
   
@@ -542,9 +666,9 @@ exports[`attributes tuple variable 1`] = `
 `;
 
 exports[`attributes two classes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"a b\\"/>\`);
   
@@ -555,9 +679,9 @@ exports[`attributes two classes 1`] = `
 `;
 
 exports[`attributes two dynamic attributes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-attribute-0=\\"foo\\" block-attribute-1=\\"bar\\"/>\`);
   
@@ -570,9 +694,9 @@ exports[`attributes two dynamic attributes 1`] = `
 `;
 
 exports[`attributes updating classes (with obj notation) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"hoy\\" block-attribute-0=\\"class\\"/>\`);
   
@@ -584,9 +708,9 @@ exports[`attributes updating classes (with obj notation) 1`] = `
 `;
 
 exports[`attributes various escapes 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div foo=\\"&lt;foo\\" block-attribute-0=\\"bar\\" block-attribute-1=\\"baz\\" block-attributes=\\"2\\"/>\`);
   
@@ -600,9 +724,9 @@ exports[`attributes various escapes 1`] = `
 `;
 
 exports[`attributes various escapes 2 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div> &lt; </div>\`);
   
@@ -611,86 +735,3 @@ exports[`attributes various escapes 2 1`] = `
   }
 }"
 `;
-
-exports[`special cases for some specific html attributes/properties input of type checkbox with t-att-indeterminate 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<input type=\\"checkbox\\" block-attribute-0=\\"indeterminate\\"/>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['v'];
-    return block1([attr1]);
-  }
-}"
-`;
-
-exports[`special cases for some specific html attributes/properties input type= checkbox, with t-att-checked 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<input type=\\"checkbox\\" block-attribute-0=\\"checked\\"/>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['flag'];
-    return block1([attr1]);
-  }
-}"
-`;
-
-exports[`special cases for some specific html attributes/properties input with t-att-value 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<input block-attribute-0=\\"value\\"/>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['v'];
-    return block1([attr1]);
-  }
-}"
-`;
-
-exports[`special cases for some specific html attributes/properties select with t-att-value 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<select block-attribute-0=\\"value\\"><option value=\\"potato\\">Potato</option><option value=\\"tomato\\">Tomato</option><option value=\\"onion\\">Onion</option></select>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['value'];
-    return block1([attr1]);
-  }
-}"
-`;
-
-exports[`special cases for some specific html attributes/properties textarea with t-att-value 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<textarea block-attribute-0=\\"value\\"/>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    let attr1 = ctx['v'];
-    return block1([attr1]);
-  }
-}"
-`;
-
-exports[`special cases for some specific html attributes/properties various boolean html attributes 1`] = `
-"function anonymous(bdom, helpers
-) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  
-  let block1 = createBlock(\`<div><input type=\\"checkbox\\" checked=\\"checked\\"/><input checked=\\"checked\\"/><div checked=\\"checked\\"/><div selected=\\"selected\\"/><option selected=\\"selected\\" other=\\"1\\"/><input readonly=\\"readonly\\"/><button disabled=\\"disabled\\"/></div>\`);
-  
-  return function template(ctx, node, key = \\"\\") {
-    return block1();
-  }
-}"
-`;

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

@@ -1,9 +1,9 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`comments only a comment 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   return function template(ctx, node, key = \\"\\") {
     return comment(\` comment\`);
@@ -12,9 +12,9 @@ exports[`comments only a comment 1`] = `
 `;
 
 exports[`comments properly handle comments 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div>hello <!-- comment-->owl</div>\`);
   
@@ -25,9 +25,9 @@ exports[`comments properly handle comments 1`] = `
 `;
 
 exports[`comments properly handle comments between t-if/t-else 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   let block2 = createBlock(\`<span>true</span>\`);

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

@@ -1,9 +1,9 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`t-on can bind event handler 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -15,9 +15,9 @@ exports[`t-on can bind event handler 1`] = `
 `;
 
 exports[`t-on can bind handlers with arguments 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -30,9 +30,9 @@ exports[`t-on can bind handlers with arguments 1`] = `
 `;
 
 exports[`t-on can bind handlers with empty  object 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -45,9 +45,9 @@ exports[`t-on can bind handlers with empty  object 1`] = `
 `;
 
 exports[`t-on can bind handlers with empty object (with non empty inner string) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -60,9 +60,9 @@ exports[`t-on can bind handlers with empty object (with non empty inner string)
 `;
 
 exports[`t-on can bind handlers with empty object (with non empty inner string) 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { prepareList, withKey } = helpers;
   
   let block1 = createBlock(\`<ul><block-child-0/></ul>\`);
@@ -87,9 +87,9 @@ exports[`t-on can bind handlers with empty object (with non empty inner string)
 `;
 
 exports[`t-on can bind handlers with object arguments 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -102,9 +102,9 @@ exports[`t-on can bind handlers with object arguments 1`] = `
 `;
 
 exports[`t-on can bind two event handlers 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\" block-handler-1=\\"dblclick\\">Click</button>\`);
   
@@ -117,9 +117,9 @@ exports[`t-on can bind two event handlers 1`] = `
 `;
 
 exports[`t-on handler is bound to proper owner 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -131,9 +131,9 @@ exports[`t-on handler is bound to proper owner 1`] = `
 `;
 
 exports[`t-on handler is bound to proper owner, part 2 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { prepareList, withKey } = helpers;
   
   let block2 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
@@ -153,11 +153,10 @@ exports[`t-on handler is bound to proper owner, part 2 1`] = `
 `;
 
 exports[`t-on handler is bound to proper owner, part 3 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { getTemplate } = helpers;
-  const callTemplate_1 = getTemplate(\`sub\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const callTemplate_1 = app.getTemplate(\`sub\`);
   
   return function template(ctx, node, key = \\"\\") {
     return callTemplate_1.call(this, ctx, node, key + \`__1\`);
@@ -166,9 +165,9 @@ exports[`t-on handler is bound to proper owner, part 3 1`] = `
 `;
 
 exports[`t-on handler is bound to proper owner, part 3 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -180,11 +179,11 @@ exports[`t-on handler is bound to proper owner, part 3 2`] = `
 `;
 
 exports[`t-on handler is bound to proper owner, part 4 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { prepareList, getTemplate, withKey } = helpers;
-  const callTemplate_1 = getTemplate(\`sub\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  const callTemplate_1 = app.getTemplate(\`sub\`);
   
   return function template(ctx, node, key = \\"\\") {
     ctx = Object.create(ctx);
@@ -204,9 +203,9 @@ exports[`t-on handler is bound to proper owner, part 4 1`] = `
 `;
 
 exports[`t-on handler is bound to proper owner, part 4 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -218,9 +217,9 @@ exports[`t-on handler is bound to proper owner, part 4 2`] = `
 `;
 
 exports[`t-on receive event in first argument 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -232,9 +231,9 @@ exports[`t-on receive event in first argument 1`] = `
 `;
 
 exports[`t-on t-on modifiers (native listener) basic support for native listener 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div class=\\"myClass\\" block-handler-0=\\"click\\"><button block-handler-1=\\"click\\">Button</button></div>\`);
   
@@ -247,9 +246,9 @@ exports[`t-on t-on modifiers (native listener) basic support for native listener
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on combined with t-esc 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click\\"><block-text-1/></button></div>\`);
   
@@ -262,9 +261,9 @@ exports[`t-on t-on modifiers (native listener) t-on combined with t-esc 1`] = `
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on combined with t-out 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click\\"><block-child-0/></button></div>\`);
@@ -278,9 +277,9 @@ exports[`t-on t-on modifiers (native listener) t-on combined with t-out 1`] = `
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with .capture modifier 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-handler-0=\\"click.capture\\"><button block-handler-1=\\"click\\">Button</button></div>\`);
   
@@ -293,9 +292,9 @@ exports[`t-on t-on modifiers (native listener) t-on with .capture modifier 1`] =
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with empty handler (only modifiers) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click.prevent\\">Button</button></div>\`);
   
@@ -307,9 +306,9 @@ exports[`t-on t-on modifiers (native listener) t-on with empty handler (only mod
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with prevent and self modifiers (order matters) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click.prevent.self\\"><span>Button</span></button></div>\`);
   
@@ -321,9 +320,9 @@ exports[`t-on t-on modifiers (native listener) t-on with prevent and self modifi
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with prevent and/or stop modifiers 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click.prevent\\">Button 1</button><button block-handler-1=\\"click.stop\\">Button 2</button><button block-handler-2=\\"click.prevent.stop\\">Button 3</button></div>\`);
   
@@ -337,9 +336,9 @@ exports[`t-on t-on modifiers (native listener) t-on with prevent and/or stop mod
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with prevent modifier in t-foreach 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { prepareList, withKey } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
@@ -364,9 +363,9 @@ exports[`t-on t-on modifiers (native listener) t-on with prevent modifier in t-f
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with self and prevent modifiers (order matters) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click.self.prevent\\"><span>Button</span></button></div>\`);
   
@@ -378,9 +377,9 @@ exports[`t-on t-on modifiers (native listener) t-on with self and prevent modifi
 `;
 
 exports[`t-on t-on modifiers (native listener) t-on with self modifier 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div><button block-handler-0=\\"click\\"><span>Button</span></button><button block-handler-1=\\"click.self\\"><span>Button</span></button></div>\`);
   
@@ -393,9 +392,9 @@ exports[`t-on t-on modifiers (native listener) t-on with self modifier 1`] = `
 `;
 
 exports[`t-on t-on modifiers (synthetic listener) basic support for synthetic 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<div block-handler-0=\\"click.synthetic\\"><button block-handler-1=\\"click.synthetic\\">Button</button></div>\`);
   
@@ -408,9 +407,9 @@ exports[`t-on t-on modifiers (synthetic listener) basic support for synthetic 1`
 `;
 
 exports[`t-on t-on with inline statement (function call) 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -423,9 +422,9 @@ exports[`t-on t-on with inline statement (function call) 1`] = `
 `;
 
 exports[`t-on t-on with inline statement 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Click</button>\`);
   
@@ -438,9 +437,9 @@ exports[`t-on t-on with inline statement 1`] = `
 `;
 
 exports[`t-on t-on with inline statement, part 2 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Toggle</button>\`);
   
@@ -453,9 +452,9 @@ exports[`t-on t-on with inline statement, part 2 1`] = `
 `;
 
 exports[`t-on t-on with inline statement, part 3 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<button block-handler-0=\\"click\\">Toggle</button>\`);
   
@@ -469,11 +468,10 @@ exports[`t-on t-on with inline statement, part 3 1`] = `
 `;
 
 exports[`t-on t-on with t-call 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { getTemplate } = helpers;
-  const callTemplate_1 = getTemplate(\`sub\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const callTemplate_1 = app.getTemplate(\`sub\`);
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
@@ -485,9 +483,9 @@ exports[`t-on t-on with t-call 1`] = `
 `;
 
 exports[`t-on t-on with t-call 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<p block-handler-0=\\"click\\">lucas</p>\`);
   
@@ -499,11 +497,10 @@ exports[`t-on t-on with t-call 2`] = `
 `;
 
 exports[`t-on t-on, with arguments and t-call 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { getTemplate } = helpers;
-  const callTemplate_1 = getTemplate(\`sub\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  const callTemplate_1 = app.getTemplate(\`sub\`);
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
@@ -515,15 +512,16 @@ exports[`t-on t-on, with arguments and t-call 1`] = `
 `;
 
 exports[`t-on t-on, with arguments and t-call 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   
   let block1 = createBlock(\`<p block-handler-0=\\"click\\">lucas</p>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const v1 = ctx['value'];
-    let hdlr1 = [()=>this.update(v1), ctx];
+    const v1 = ctx['this'];
+    const v2 = ctx['value'];
+    let hdlr1 = [()=>v1.update(v2), ctx];
     return block1([hdlr1]);
   }
 }"

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

@@ -1,10 +1,11 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`misc complex template 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { prepareList, withKey } = helpers;
+  const comp1 = app.createComponent(\`SlotButton\`, true, false, false, [\\"class\\",\\"slot\\"]);
   
   let block1 = createBlock(\`<div block-attribute-0=\\"class\\"><div block-attribute-1=\\"class\\"><div class=\\"batch_header\\"><a block-attribute-2=\\"href\\" block-attribute-3=\\"class\\" title=\\"View Batch\\"><block-text-4/><block-child-0/><i class=\\"arrow fa fa-window-maximize\\"/></a></div><block-child-1/><div class=\\"batch_slots\\"><block-child-2/><block-child-3/></div><div class=\\"batch_commits\\"><block-child-4/></div></div></div>\`);
   let block2 = createBlock(\`<i class=\\"fa fa-exclamation-triangle\\"/>\`);
@@ -34,7 +35,7 @@ exports[`misc complex template 1`] = `
     for (let i1 = 0; i1 < l_block4; i1++) {
       ctx[\`slot\`] = v_block4[i1];
       const key1 = ctx['slot'].id;
-      c_block4[i1] = withKey(component(\`SlotButton\`, {class: ctx['slot_container'], slot: ctx['slot']}, key + \`__1__\${key1}\`, node, ctx), key1);
+      c_block4[i1] = withKey(comp1({class: ctx['slot_container'],slot: ctx['slot']}, key + \`__1__\${key1}\`, node, this, null), key1);
     }
     ctx = ctx.__proto__;
     b4 = list(c_block4);
@@ -79,15 +80,15 @@ exports[`misc complex template 1`] = `
 `;
 
 exports[`misc global 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { prepareList, isBoundary, withDefault, setContextValue, getTemplate, zero, withKey } = helpers;
-  const callTemplate_1 = getTemplate(\`_callee-uses-foo\`);
-  const callTemplate_2 = getTemplate(\`_callee-uses-foo\`);
-  const callTemplate_3 = getTemplate(\`_callee-uses-foo\`);
-  const callTemplate_4 = getTemplate(\`_callee-asc\`);
-  const callTemplate_5 = getTemplate(\`_callee-asc-toto\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, isBoundary, withDefault, setContextValue, zero, withKey } = helpers;
+  const callTemplate_1 = app.getTemplate(\`_callee-uses-foo\`);
+  const callTemplate_2 = app.getTemplate(\`_callee-uses-foo\`);
+  const callTemplate_3 = app.getTemplate(\`_callee-uses-foo\`);
+  const callTemplate_4 = app.getTemplate(\`_callee-asc\`);
+  const callTemplate_5 = app.getTemplate(\`_callee-asc-toto\`);
   
   let block1 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   let block4 = createBlock(\`<span><block-text-0/></span>\`);
@@ -131,9 +132,9 @@ exports[`misc global 1`] = `
 `;
 
 exports[`misc global 2`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { withDefault } = helpers;
   
   let block1 = createBlock(\`<span><block-text-0/></span>\`);
@@ -146,9 +147,9 @@ exports[`misc global 2`] = `
 `;
 
 exports[`misc global 3`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
   let { zero } = helpers;
   
   let block1 = createBlock(\`<año block-attribute-0=\\"falló\\"><block-child-0/></año>\`);
@@ -162,29 +163,31 @@ exports[`misc global 3`] = `
 `;
 
 exports[`misc global 4`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { safeOutput, withDefault } = helpers;
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { safeOutput } = helpers;
   
   let block1 = createBlock(\`<div><block-child-0/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
     const b3 = text(\`toto default\`);
-    const b2 = withDefault(safeOutput(ctx['toto']), b3);
+    const b2 = safeOutput(ctx['toto'], b3);
     return block1([], [b2]);
   }
 }"
 `;
 
 exports[`misc other complex template 1`] = `
-"function anonymous(bdom, helpers
+"function anonymous(app, bdom, helpers
 ) {
-  let { text, createBlock, list, multi, html, toggler, component, comment } = bdom;
-  let { prepareList, withKey, getTemplate } = helpers;
-  const callTemplate_1 = getTemplate(\`LOAD_INFOS_TEMPLATE\`);
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  let { prepareList, withKey } = helpers;
+  const callTemplate_1 = app.getTemplate(\`LOAD_INFOS_TEMPLATE\`);
+  const comp1 = app.createComponent(\`BundlesList\`, true, false, false, [\\"bundles\\",\\"category_custom_views\\",\\"search\\"]);
+  const comp2 = app.createComponent(\`BundlesList\`, true, false, false, [\\"bundles\\",\\"search\\"]);
   
-  let block1 = createBlock(\`<div><header><nav class=\\"navbar navbar-expand-md navbar-light bg-light\\"><a block-attribute-0=\\"href\\"><b style=\\"color:#777;\\"><block-text-1/></b></a><button type=\\"button\\" class=\\"navbar-toggler\\" data-toggle=\\"collapse\\" data-target=\\"#top_menu_collapse\\"><span class=\\"navbar-toggler-icon\\"/></button><div class=\\"collapse navbar-collapse\\" id=\\"top_menu_collapse\\" aria-expanded=\\"false\\"><ul class=\\"nav navbar-nav ml-auto text-right\\" id=\\"top_menu\\"><block-child-0/><li class=\\"nav-item divider\\"/><block-child-1/></ul><div><div class=\\"input-group input-group-sm\\"><div class=\\"input-group-prepend input-group-sm\\"><button class=\\"btn btn-default fa fa-cog\\" title=\\"Settings\\" block-handler-2=\\"click\\"/><button class=\\"btn btn-default\\" block-handler-3=\\"click\\"> More </button><block-child-2/></div><input class=\\"form-control\\" type=\\"text\\" placeholder=\\"Search\\" aria-label=\\"Search\\" name=\\"search\\" block-attribute-4=\\"value\\" block-handler-5=\\"keyup\\" block-handler-6=\\"change\\" block-ref=\\"7\\"/><div class=\\"input-group-append\\"><button class=\\"btn btn-default fa fa-eraser\\" block-handler-8=\\"click\\"/></div></div></div></div></nav></header><div class=\\"container-fluid\\" block-ref=\\"9\\"><div class=\\"row\\"><!--div class=\\"form-group col-md-6\\">
+  let block1 = createBlock(\`<div><header><nav class=\\"navbar navbar-expand-md navbar-light bg-light\\"><a block-attribute-0=\\"href\\"><b style=\\"color:#777;\\"><block-text-1/></b></a><button type=\\"button\\" class=\\"navbar-toggler\\" data-toggle=\\"collapse\\" data-target=\\"#top_menu_collapse\\"><span class=\\"navbar-toggler-icon\\"/></button><div class=\\"collapse navbar-collapse\\" id=\\"top_menu_collapse\\" aria-expanded=\\"false\\"><ul class=\\"nav navbar-nav ml-auto text-right\\" id=\\"top_menu\\"><block-child-0/><li class=\\"nav-item divider\\"/><block-child-1/></ul><div><div class=\\"input-group input-group-sm\\"><div class=\\"input-group-prepend input-group-sm\\"><button class=\\"btn btn-default fa fa-cog\\" title=\\"Settings\\" block-handler-2=\\"click\\"/><button class=\\"btn btn-default\\" block-handler-3=\\"click\\"> More </button><block-child-2/></div><input class=\\"form-control\\" type=\\"text\\" placeholder=\\"Search\\" aria-label=\\"Search\\" name=\\"search\\" block-property-4=\\"value\\" block-handler-5=\\"keyup\\" block-handler-6=\\"change\\" block-ref=\\"7\\"/><div class=\\"input-group-append\\"><button class=\\"btn btn-default fa fa-eraser\\" block-handler-8=\\"click\\"/></div></div></div></div></nav></header><div class=\\"container-fluid\\" block-ref=\\"9\\"><div class=\\"row\\"><!--div class=\\"form-group col-md-6\\">
                       <h5>Search options</h5>
                       <input class=\\"form-control\\" type=\\"text\\" name=\\"default_search\\" id=\\"default_search\\" t-att-checked=\\"default_search\\" placeholder=\\"Default search\\"/>
       
@@ -206,17 +209,14 @@ exports[`misc other complex template 1`] = `
   let block12 = createBlock(\`<li class=\\"nav-item divider\\"/>\`);
   let block13 = createBlock(\`<li class=\\"nav-item dropdown\\"><a href=\\"#\\" class=\\"nav-link dropdown-toggle\\" data-toggle=\\"dropdown\\"><b><span><block-text-0/></span></b></a><div class=\\"dropdown-menu js_usermenu\\" role=\\"menu\\"><a class=\\"dropdown-item\\" id=\\"o_logout\\" role=\\"menuitem\\" block-attribute-1=\\"href\\">Logout</a><a class=\\"dropdown-item\\" role=\\"menuitem\\" block-attribute-2=\\"href\\">Web</a></div></li>\`);
   let block14 = createBlock(\`<select class=\\"custom-select\\" name=\\"category\\" id=\\"category\\"><block-child-0/></select>\`);
-  let block16 = createBlock(\`<option block-attribute-0=\\"value\\" block-attribute-1=\\"selected\\"><block-text-2/></option>\`);
-  let block20 = createBlock(\`<div class=\\"form-check\\"><input class=\\"form-check-input\\" type=\\"checkbox\\" block-attribute-0=\\"name\\" block-attribute-1=\\"id\\" block-attribute-2=\\"checked\\" block-attribute-3=\\"data-trigger_id\\" block-handler-4=\\"change\\"/><label class=\\"form-check-label\\" block-attribute-5=\\"for\\"><block-text-6/></label></div>\`);
+  let block16 = createBlock(\`<option block-attribute-0=\\"value\\" block-property-1=\\"selected\\"><block-text-2/></option>\`);
+  let block20 = createBlock(\`<div class=\\"form-check\\"><input class=\\"form-check-input\\" type=\\"checkbox\\" block-attribute-0=\\"name\\" block-attribute-1=\\"id\\" block-property-2=\\"checked\\" block-attribute-3=\\"data-trigger_id\\" block-handler-4=\\"change\\"/><label class=\\"form-check-label\\" block-attribute-5=\\"for\\"><block-text-6/></label></div>\`);
   let block21 = createBlock(\`<div><button class=\\"btn btn-sm btn-default\\" block-handler-0=\\"click\\">All</button><button class=\\"btn btn-sm btn-default\\" block-handler-1=\\"click\\">None</button><button class=\\"btn btn-sm btn-info\\" block-handler-2=\\"click\\">Default</button><button class=\\"btn btn-sm btn-default\\" block-handler-3=\\"click\\">Close</button></div>\`);
   let block23 = createBlock(\`<div class=\\"alert alert-warning\\" role=\\"alert\\"><block-text-0/> <!-- todo fixme--></div>\`);
   let block24 = createBlock(\`<div class=\\"mb32\\"><h1>No project</h1></div>\`);
   let block25 = createBlock(\`<div><block-child-0/><block-child-1/></div>\`);
   
   return function template(ctx, node, key = \\"\\") {
-    const refs = ctx.__owl__.refs;
-    const ref1 = (el) => refs[\`search_input\`] = el;
-    const ref2 = (el) => refs[\`settings_menu\`] = el;
     let b2,b4,b14,b17,b22,b23,b24,b25;
     let attr1 = \`/runbot/\${ctx['project'].slug}\`;
     let txt1 = ctx['project'].name;
@@ -266,18 +266,20 @@ exports[`misc other complex template 1`] = `
         ctx[\`category\`] = v_block15[i1];
         const key1 = ctx['category'].id;
         let attr6 = ctx['category'].id;
-        let attr7 = ctx['category'].id==ctx['options'].active_category_id;
+        let prop1 = new Boolean(ctx['category'].id==ctx['options'].active_category_id);
         let txt5 = ctx['category'].name;
-        c_block15[i1] = withKey(block16([attr6, attr7, txt5]), key1);
+        c_block15[i1] = withKey(block16([attr6, prop1, txt5]), key1);
       }
       ctx = ctx.__proto__;
       const b15 = list(c_block15);
       b14 = block14([], [b15]);
     }
-    let attr8 = ctx['search'].value;
+    let prop2 = new String((ctx['search'].value) === 0 ? 0 : ((ctx['search'].value) || \\"\\"));
     let hdlr4 = [ctx['updateFilter'], ctx];
     let hdlr5 = [ctx['updateFilter'], ctx];
+    let ref1 = (el) => this.__owl__.setRef((\`search_input\`), el);
     let hdlr6 = [ctx['clearSearch'], ctx];
+    let ref2 = (el) => this.__owl__.setRef((\`settings_menu\`), el);
     if (ctx['triggers']) {
       ctx = Object.create(ctx);
       const [k_block18, v_block18, l_block18, c_block18] = prepareList(ctx['triggers']);;
@@ -286,14 +288,14 @@ exports[`misc other complex template 1`] = `
         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) {
-          let attr9 = \`trigger_\${ctx['trigger'].id}\`;
-          let attr10 = \`trigger_\${ctx['trigger'].id}\`;
-          let attr11 = ctx['options'].trigger_display[ctx['trigger'].id];
-          let attr12 = ctx['trigger'].id;
+          let attr7 = \`trigger_\${ctx['trigger'].id}\`;
+          let attr8 = \`trigger_\${ctx['trigger'].id}\`;
+          let prop3 = new Boolean(ctx['options'].trigger_display[ctx['trigger'].id]);
+          let attr9 = ctx['trigger'].id;
           let hdlr7 = [ctx['updateTriggerDisplay'], ctx];
-          let attr13 = \`trigger_\${ctx['trigger'].id}\`;
+          let attr10 = \`trigger_\${ctx['trigger'].id}\`;
           let txt6 = ctx['trigger'].name;
-          b20 = block20([attr9, attr10, attr11, attr12, hdlr7, attr13, txt6]);
+          b20 = block20([attr7, attr8, prop3, attr9, hdlr7, attr10, txt6]);
         }
         c_block18[i1] = withKey(multi([b20]), key1);
       }
@@ -316,11 +318,11 @@ exports[`misc other complex template 1`] = `
     if (!ctx['project']) {
       b24 = block24();
     } else {
-      const b26 = component(\`BundlesList\`, {bundles: ctx['bundles'].sticky, category_custom_views: ctx['category_custom_views'], search: ctx['search']}, key + \`__2\`, node, ctx);
-      const b27 = component(\`BundlesList\`, {bundles: ctx['bundles'].dev, search: ctx['search']}, key + \`__3\`, node, ctx);
+      const b26 = comp1({bundles: ctx['bundles'].sticky,category_custom_views: ctx['category_custom_views'],search: ctx['search']}, key + \`__2\`, node, this, null);
+      const b27 = comp2({bundles: ctx['bundles'].dev,search: ctx['search']}, key + \`__3\`, node, this, null);
       b25 = block25([], [b26, b27]);
     }
-    return block1([attr1, txt1, hdlr2, hdlr3, attr8, hdlr4, hdlr5, ref1, hdlr6, ref2], [b2, b4, b14, b17, b22, b23, b24, b25]);
+    return block1([attr1, txt1, hdlr2, hdlr3, prop2, hdlr4, hdlr5, ref1, hdlr6, ref2], [b2, b4, b14, b17, b22, b23, b24, b25]);
   }
 }"
 `;

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

@@ -0,0 +1,250 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`changing an attribute with t-att- 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div block-attribute-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let attr1 = ctx['v'];
+    return block1([attr1]);
+  }
+}"
+`;
+
+exports[`dynamic input value: falsy values 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((0) === 0 ? 0 : ((0) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`dynamic input value: falsy values 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((false) === 0 ? 0 : ((false) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`dynamic input value: falsy values 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((undefined) === 0 ? 0 : ((undefined) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`dynamic input value: falsy values 4`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String(('') === 0 ? 0 : (('') || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`input of type checkbox with t-att-indeterminate 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input type=\\"checkbox\\" block-property-0=\\"indeterminate\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new Boolean(ctx['v']);
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`input type= checkbox, with t-att-checked 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input type=\\"checkbox\\" block-property-0=\\"checked\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new Boolean(ctx['flag']);
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`input with t-att-value (patching with same value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((ctx['v']) === 0 ? 0 : ((ctx['v']) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`input with t-att-value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((ctx['v']) === 0 ? 0 : ((ctx['v']) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`input, type checkbox, with t-att-checked (patching with same value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input type=\\"checkbox\\" block-property-0=\\"checked\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new Boolean(ctx['v']);
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`readonly and readOnly are both interpreted as the readOnly property 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input readonly=\\"\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`readonly and readOnly are both interpreted as the readOnly property 2`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input readOnly=\\"\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;
+
+exports[`readonly and readOnly are both interpreted as the readOnly property 3`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"readOnly\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new Boolean(ctx['val']);
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`readonly and readOnly are both interpreted as the readOnly property 4`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"readOnly\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new Boolean(ctx['val']);
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`select with t-att-value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<select block-property-0=\\"value\\"><option value=\\"potato\\">Potato</option><option value=\\"tomato\\">Tomato</option><option value=\\"onion\\">Onion</option></select>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((ctx['value']) === 0 ? 0 : ((ctx['value']) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`textarea with t-att-value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<textarea block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((ctx['v']) === 0 ? 0 : ((ctx['v']) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`updating property with falsy value 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<input block-property-0=\\"value\\"/>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    let prop1 = new String((ctx['v']) === 0 ? 0 : ((ctx['v']) || \\"\\"));
+    return block1([prop1]);
+  }
+}"
+`;
+
+exports[`various boolean html attributes 1`] = `
+"function anonymous(app, bdom, helpers
+) {
+  let { text, createBlock, list, multi, html, toggler, comment } = bdom;
+  
+  let block1 = createBlock(\`<div><input type=\\"checkbox\\" checked=\\"checked\\"/><input checked=\\"checked\\"/><div checked=\\"checked\\"/><div selected=\\"selected\\"/><option selected=\\"selected\\" other=\\"1\\"/><input readonly=\\"readonly\\"/><button disabled=\\"disabled\\"/></div>\`);
+  
+  return function template(ctx, node, key = \\"\\") {
+    return block1();
+  }
+}"
+`;