[REL] bump to v0.16.0

closes #214

.gitignore

@@ -1,5 +1,6 @@
 /node_modules
 /dist
+
 npm-debug.log
 
 # misc
@@ -14,8 +15,12 @@ yarn-debug.log*
 yarn-error.log*
 
 package-lock.json
+
+#ide's
 .vscode
+.idea
+
 node_modules
 
 # Extras temp file
-/extras/owl.js
+/tools/owl.js

LICENSE

@@ -1,12 +1,9 @@
-
-For copyright information, please see the COPYRIGHT file.
-
-Odoo is published under the GNU LESSER GENERAL PUBLIC LICENSE, Version 3
+OWL is published under the GNU LESSER GENERAL PUBLIC LICENSE, Version 3
 (LGPLv3), as included below. Since the LGPL is a set of additional
 permissions on top of the GPL, the text of the GPL is included at the
 bottom as well.
 
-Some external libraries and contributions bundled with Odoo may be published
+Some external libraries and contributions bundled with OWL may be published
 under other GPL-compatible licenses. For these, please refer to the relevant
 source files and/or license files, in the source code tree.
 

README.md

@@ -10,7 +10,7 @@ other Odoo related projects. OWL's main feature is a _declarative component syst
 
 **Try it online!** An online playground is available at [https://odoo.github.io/owl/playground](https://odoo.github.io/owl/playground) to let you experiment with the OWL framework.
 
-## OWL's design principles
+## OWL's Design Principles
 
 OWL is designed to be used in highly dynamic applications where changing
 requirements are common, code needs to be maintained by large teams.
@@ -30,17 +30,20 @@ Owl is not designed to be fast or small (even though it is quite good on those
 two topics). If you are interested in a comparison with React or Vue, you will
 find some more information [here](doc/comparison.md).
 
-# Example
+## Example
 
-Here is a short example to illustrate interactive widgets:
+Here is a short example to illustrate interactive components:
+
+```xml
+<templates>
+  <button t-name="Counter" t-on-click="increment">
+    Click Me! [<t t-esc="state.value"/>]
+  </button>
+</templates>
+```
 
 ```javascript
-class ClickCounter extends owl.Component {
-  inlineTemplate = `
-    <button t-on-click="increment">
-      Click Me! [<t t-esc="state.value"/>]
-    </button>`;
-
+class Counter extends owl.Component {
   state = { value: 0 };
 
   increment() {
@@ -48,30 +51,33 @@ class ClickCounter extends owl.Component {
   }
 }
 
-const qweb = new owl.QWeb();
-const counter = new ClickCounter({ qweb });
+const qweb = new owl.QWeb(TEMPLATES);
+const counter = new Counter({ qweb });
 counter.mount(document.body);
 ```
 
-More interesting examples can be found on the [playground](https://odoo.github.io/owl/playground) application.
+Note that we assume here that the xml templates are available in the `TEMPLATES`
+string. More interesting examples can be found on the
+[playground](https://odoo.github.io/owl/playground) application.
 
 ## Installing/Building
 
 If you want to use a simple `<script>` tag, the last release can be downloaded here:
 
-- [owl-0.9.0.js](https://github.com/odoo/owl/releases/download/v0.9.0/owl-0.9.0.js)
-- [owl-0.9.0.min.js](https://github.com/odoo/owl/releases/download/v0.9.0/owl-0.9.0.min.js)
+- [owl-0.16.0.js](https://github.com/odoo/owl/releases/download/v0.16.0/owl.js)
+- [owl-0.16.0.min.js](https://github.com/odoo/owl/releases/download/v0.16.0/owl.min.js)
 
 Some npm scripts are available:
 
-| Command              | Description                                                                     |
-| -------------------- | ------------------------------------------------------------------------------- |
-| `npm install`        | install every dependency required for this project                              |
-| `npm run build`      | build a bundle of _owl_ in the _/dist/_ folder                                  |
-| `npm run minify`     | minify the prebuilt owl.js file                                                 |
-| `npm run test`       | run all tests                                                                   |
-| `npm run test:watch` | run all tests, and keep a watcher                                               |
-| `npm run extras`     | build extras applications, start a static server (see [here](extras/readme.md)) |
+| Command               | Description                                                                  |
+| --------------------- | ---------------------------------------------------------------------------- |
+| `npm install`         | install every dependency required for this project                           |
+| `npm run build`       | build a bundle of _owl_ in the _/dist/_ folder                               |
+| `npm run minify`      | minify the prebuilt owl.js file                                              |
+| `npm run test`        | run all tests                                                                |
+| `npm run test:watch`  | run all tests, and keep a watcher                                            |
+| `npm run tools`       | build tools applications, start a static server (see [here](doc/tooling.md)) |
+| `npm run tools:watch` | same as `tools`, but with a watcher to rebuild owl                           |
 
 ## Documentation
 
@@ -81,6 +87,9 @@ The complete documentation can be found [here](doc/readme.md). The most importan
 - [Component](doc/component.md)
 - [QWeb](doc/qweb.md)
 
+Found an issue in the documentation? A broken link? Some outdated information?
+Submit a PR!
+
 ## License
 
 OWL is [GPL licensed](./LICENSE).

doc/animations.md

@@ -1,23 +1,25 @@
 # 🦉 Animations 🦉
 
-
 Animation is a complex topic. There are many different use cases, and many
-solutions and technologies.
+solutions and technologies. Owl only supports some basic use cases.
 
 ## Simple CSS effects
 
-Sometimes, using pure CSS is enough.  For these use cases, Owl is not really
+Sometimes, using pure CSS is enough. For these use cases, Owl is not really
 necessary: it just needs to render a DOM element with a specific class. For
 example:
 
-
 ```xml
-<button class="flash" t-on-click="doSomething">Click</button>
+<a class="btn flash" t-on-click="doSomething">Click</a>
 ```
 
 with the following CSS:
 
 ```css
+btn {
+  background-color: gray;
+}
+
 .flash {
   transition: background 0.5s;
 }
@@ -31,9 +33,64 @@ with the following CSS:
 will produce a nice flash effect whenever the user click (or activate with the
 keyboard) the button.
 
-## CSS Transitions (single element)
+## CSS Transitions
 
 A more complex situation occurs when we want to transition an element in or out
-of the page.  For example, we may want a fade-in and fade-out effect.
+of the page. For example, we may want a fade-in and fade-out effect.
 
-The `t-transition` directive is here to help us (see [QWeb documentation](doc/qweb.md#t-transition-directive)).
+The `t-transition` directive is here to help us. It works on html elements and
+on components, by adding and removing some css classes.
+
+To perform useful transition effects, whenever an element appears or disappears,
+it is necessary to add/remove some css style or class at some precise moment in
+the lifetime of a node. Since this is not easy to do by hand, Owl `t-transition`
+directive is there to help.
+
+Whenever a node has a `t-transition` directive, with a `name` value, the following
+will happen:
+
+At node insertion:
+
+- the css classes `name-enter` and `name-enter-active` will be added directly
+  when the node is inserted into the DOM,
+- on the next animation frame: the css class `name-enter` will be removed and the
+  class `name-enter-to` will be added (so they can be used to trigger css
+  transition effects),
+- the css class `name-enter-active` will be removed whenever a css transition
+  ends.
+
+At node destruction:
+
+- the css classes `name-leave` and `name-leave-active` will be added before the
+  node is removed to the DOM,
+- the css class `name-leave` will be removed on the next animation frame (so it
+  can be used to trigger css transition effects),
+- the css class `name-leave-active` will be removed whenever a css transition
+  ends. Only then will the element be removed from the DOM.
+
+For example, a simple fade in/out effect can be done with this:
+
+```xml
+<div>
+    <div t-if="state.flag" class="square" t-transition="fade">Hello</div>
+</div>
+```
+
+```css
+.fade-enter-active,
+.fade-leave-active {
+  transition: opacity 0.5s;
+}
+.fade-enter,
+.fade-leave-to {
+  opacity: 0;
+}
+```
+
+The `t-transition` directive can be applied on a node element or on a component.
+
+Notes:
+
+- more information on animations are available [here](animations.md).
+- Owl does not support more than one transition on a single node, so the
+  `t-transition` expression must be a single value (i.e. no space allowed)

doc/comparison.md

@@ -7,6 +7,8 @@ In this page, we try to highlight some of these differences. Obviously, some
 effort was done to be fair. However, if you disagree with some of the points
 discussed, feel free to open an issue/submit a PR to correct this text.
 
+## Content
+
 - [Size](#size)
 - [Tooling/Build Step](#toolingbuild-step)
 - [Templating](#templating)
@@ -14,7 +16,7 @@ discussed, feel free to open an issue/submit a PR to correct this text.
 - [Reactiveness](#reactiveness)
 - [State Management](#state-management)
 
-### Size
+## Size
 
 OWL is intended to be small and to work at a slightly lower level of abstraction
 than React and Vue. Also, jQuery is not the same kind of framework, but it is interesting to compare.
@@ -26,7 +28,7 @@ than React and Vue. Also, jQuery is not the same kind of framework, but it is in
 | React + ReactDOM + Redux |                 | 40kb                     |
 | jQuery                   | 86kb            | 30kb                     |
 
-### Tooling/Build step
+## Tooling/Build step
 
 OWL is designed to be easy to use in a standalone way. For various reasons,
 Odoo does not want to rely on standard web tools (such as webpack), and OWL can
@@ -84,22 +86,22 @@ This has the advantage of having the full power of Javascript, but is less
 structured than a template language. Note that the tooling is quite impressive:
 there is a syntax highlighter for jsx here on github!
 
-### Asynchronous rendering
+## Asynchronous Rendering
 
 This is actually a big difference between OWL and React/Vue: components in OWL
 are totally asynchronous. They have two asynchronous hooks in their lifecycle:
 
-- `willStart` (before the widget starts rendering)
+- `willStart` (before the component starts rendering)
 - `willUpdateProps` (before new props are set)
 
 Both these methods can be implemented and return a promise. The rendering will
 then wait for these promises to be completed before patching the DOM. This is
-useful for some use cases: for example, a widget may want to fetch an external
-library (a calendar widget may need a specialized calendar rendering library),
+useful for some use cases: for example, a component may want to fetch an external
+library (a calendar component may need a specialized calendar rendering library),
 in its willStart hook.
 
 ```javascript
-class MyCalendarWidget extends owl.Component {
+class MyCalendarComponent extends owl.Component {
     ...
 
     willStart() {
@@ -115,7 +117,7 @@ extremely powerful as well, as demonstrated by the Odoo Web Client.
 Lazy loading static libraries can obviously be done with React/Vue, but it is
 more convoluted.
 
-### Reactiveness
+## Reactiveness
 
 React has a simple model: whenever the state changes, it is
 replaced with a new state (via the setState method). Then, the DOM is patched.
@@ -129,7 +131,7 @@ Owl is closer to vue: it also tracks magically the state properties, but it does
 only increment a counter whenever it changes (and a _deep_ counter for each of
 its parents). This assumes that the state is actually a tree.
 
-### State Management
+## State Management
 
 Managing the state of an application is a tricky issue. Many solutions have
 been proposed these last few years. It also depends on the kind of application we
@@ -190,5 +192,5 @@ keeps track of who get data, and retrigger a render when it was changed.
 
 Owl store is a little bit like a mix of redux and vuex: it has mutations and
 actions, like VueX, it keeps track of the state changes, but it does not notify
-a component when the state changes.  Instead, components need to connect to the
+a component when the state changes. Instead, components need to connect to the
 store like in redux, with a function that will listen to the relevant state.

doc/component.md

@@ -4,11 +4,23 @@
 
 - [Overview](#overview)
 - [Example](#example)
-- [Templates](#templates)
 - [Reference](#reference)
   - [Properties](#properties)
+  - [Static Properties](#static-properties)
   - [Methods](#methods)
   - [Lifecycle](#lifecycle)
+  - [Root Component](#root-component)
+  - [Environment](#environment)
+  - [Composition](#composition)
+  - [Event Handling](#event-handling)
+  - [Form Input Bindings](#form-input-bindings)
+  - [`t-key` Directive](#t-key-directive)
+  - [`t-mounted` Directive](#t-mounted-directive)
+  - [Semantics](#semantics)
+  - [Props Validation](#props-validation)
+  - [References](#references)
+  - [Slots](#slots)
+  - [Asynchronous Rendering](#asynchronous-rendering)
 
 ## Overview
 
@@ -17,20 +29,20 @@ OWL components are the building blocks for user interface. They are designed to
 1. **declarative:** the user interface should be described in term of the state
    of the application, not as a sequence of imperative steps.
 
-2. **composable:** each widget can seamlessly be created in a parent widget by
-   a simple directive in its template.
+2. **composable:** each component can seamlessly be created in a parent component by
+   a simple tag or directive in its template.
 
 3. **asynchronous rendering:** the framework will transparently wait for each
-   subwidgets to be ready before applying the rendering. It uses native promises
+   sub components to be ready before applying the rendering. It uses native promises
    under the hood.
 
 4. **uses QWeb as a template system:** the templates are described in XML
    and follow the QWeb specification. This is a requirement for Odoo.
 
 OWL components are defined as a subclass of Component. The rendering is
-exclusively done by a [QWeb](qweb.md) template (either defined inline or preloaded in QWeb).
-The rendering is done by QWeb, which will generate a virtual dom representation
-of the widget, then patch the DOM to apply the changes in an efficient way.
+exclusively done by a [QWeb](qweb.md) template (which needs to be preloaded in QWeb).
+Rendering a component generates a virtual dom representation
+of the component, which is then patched to the DOM, in order to apply the changes in an efficient way.
 
 OWL components observe their states, and rerender themselves whenever it is
 changed. This is done by an [observer](observer.md).
@@ -41,7 +53,6 @@ Let us have a look at a simple component:
 
 ```javascript
 class ClickCounter extends owl.Component {
-  template = "click-counter";
   state = { value: 0 };
 
   increment() {
@@ -51,7 +62,7 @@ class ClickCounter extends owl.Component {
 ```
 
 ```xml
-<button t-name="click-counter" t-on-click="increment">
+<button t-name="ClickCounter" t-on-click="increment">
   Click Me! [<t t-esc="state.value"/>]
 </button>
 ```
@@ -60,38 +71,23 @@ Note that this code is written in ESNext style, so it will only run on the
 latest browsers without a transpilation step.
 
 This example show how a component should be defined: it simply subclasses the
-Component class. It needs to define a template (`click-counter` here). Also,
+Component class. If no `template` key is defined, then
+Owl will use the component's name as template name. Here,
 a state object is defined. It is not mandatory to use the state object, but it
 is certainly encouraged. The state object is [observed](observer.md), and any
 change to it will cause a rerendering.
 
-## Templates
-
-The example above shows a QWeb template with a `t-on-click` directive.  Widget
-templates are standard [QWeb](qweb.md) templates, but with an extra directive:
-`t-widget`.  With the `t-widget` directive, widget templates can declare sub
-widgets:
-
-```xml
-  <div>
-    <span>some text</span>
-    <t t-widget="MyWidget" t-props="{info: 13}">
-  </div>
-```
-
-In this example, the template create a widget MyWidget just after the span. See
-the [QWeb](qweb.md) documentation for more information on the `t-widget` directive.
-
-Note that the rendering context for the template is the widget itself.  This means
-that the template can access `state`, `props`, `env`, or any methods defined in the widget.
-
 ## Reference
 
-An Owl component is a small class which represent a widget or some UI element.
+An Owl component is a small class which represent a component or some UI element.
 It exists in the context of an environment (`env`), which is propagated from a
 parent to its children. The environment needs to have a QWeb instance, which
 will be used to render the component template.
 
+Be aware that the name of the component may be significant: if a component does
+not define a `template` key, then Owl will lookup in QWeb to
+find a template with the component name (or one of its ancestor).
+
 ### Properties
 
 - **`el`** (HTMLElement | null): reference to the DOM root node of the element. It is `null` when the
@@ -99,26 +95,36 @@ will be used to render the component template.
 
 - **`env`** (Object): the component environment, which contains a QWeb instance.
 
-- **`template`** (string): a string, which is the name of the QWeb template that will render
+- **`template`** (string, optional): if given, this is the name of the QWeb template that will render
   the component.
 
-- **`inlineTemplate`** (string, optional): a string that represents a xml template. If set,
-  this will be loaded into QWeb and used instead of the `template` property.
-
 - **`state`** (Object): this is the location of the component's state, if there is
   any. After the willStart method, the `state` property is observed, and each
-  change will cause the widget to rerender itself.
+  change will cause the component to rerender itself.
 
 - **`props`** (Object): this is an object given (in the constructor) by the parent
   to configure the component. It can be dynamically changed later by the parent,
   in some case. Note that `props` are owned by the parent, not by the component.
-  As such, it should not ever be modified by the component.
+  As such, it should not ever be modified by the component!!
 
 - **`refs`** (Object): the `refs` object contains all references to sub DOM nodes
-  or sub widgets defined by a `t-ref` directive in the component's template.
+  or sub components defined by a `t-ref` directive in the component's template.
+
+### Static Properties
+
+- **`props`** (Object, optional): if given, this is an object that describes the
+  type and shape of the (actual) props given to the component. If Owl mode is
+  `dev`, this will be used to validate the props each time the component is
+  created/updated. See [Props Validation](#props-validation) for more information.
+- **`defaultProps`** (Object, optional): if given, this object define default
+  values for (top-level) props. Whenever `props` are given to the object, they
+  will be altered to add default value (if missing). Note that it does not
+  change the initial object, a new object will be created instead.
 
 ### Methods
 
+We explain here all the public methods of the `Component` class.
+
 - **`mount(target)`** (async): this is the main way a component's hierarchy is added to the
   DOM: the root component is mounted to a target HTMLElement. Obviously, this
   is asynchronous, since each children need to be created as well. Most applications
@@ -136,7 +142,7 @@ will be used to render the component template.
   DOM in the same stack frame.
 
 - **`shouldUpdate(nextProps)`**: this method is called each time a component's props
-  are updated. It returns a boolean, which indicates if the widget should
+  are updated. It returns a boolean, which indicates if the component should
   ignore a props update. If it returns false, then `willUpdateProps` will not
   be called, and no rendering will occur. Its default implementation is to
   always return true. This is an optimization, similar to React's `shouldComponentUpdate`. Most of the time, this should not be used, but it
@@ -147,32 +153,32 @@ will be used to render the component template.
   if we have a `isMobile` key in the environment, to decide if we want a mobile
   interface or a destkop one.
 
-- **`set(target, key, value)`**. This method is necessary in some cases when we
-  need to modify the state of the component in a way that is not visible to the
-  observer (see [observer's technical limitations](observer.md#technical-limitations)).
-  For example, if we need to add a key to the state.
-
 - **`destroy()`**. As its name suggests, this method will remove the component,
   and perform all necessary cleanup, such as unmounting the component, its children,
   removing the parent/children relationship. This method should almost never be
   called directly (except maybe on the root component), but should be done by the
   framework instead.
 
+Obviously, these methods are reserved for Owl, and should not be used by Owl
+users, unless they want to override them.  Also, Owl reserves all method names
+starting with `__`, in order to prevent possible future conflicts with user code
+whenever Owl needs to change.
+
 ### Lifecycle
 
 A solid and robust component system needs useful hooks/methods to help
 developers write components. Here is a complete description of the lifecycle of
 a owl component:
 
-| Method                                           | Description                             |
-| ------------------------------------------------ | --------------------------------------- |
-| **[constructor](#constructor)**                  | constructor                             |
-| **[willStart](#willStart)**                      | async, before first rendering           |
-| **[mounted](#mounted)**                          | when component is render and in DOM     |
-| **[willUpdateProps](#willupdatepropsnextprops)** | async, before props update              |
-| **[willPatch](#willpatch)**              | just before the DOM is patched          |
-| **[patched](#patchedsnapshot)**                          | just after the DOM is patched           |
-| **[willUnmount](#willUnmount)**                  | just before removing component from DOM |
+| Method                                           | Description                                           |
+| ------------------------------------------------ | ----------------------------------------------------- |
+| **[constructor](#constructorparent-props)**      | constructor                                           |
+| **[willStart](#willstart)**                      | async, before first rendering                         |
+| **[mounted](#mounted)**                          | just after component is rendered and added to the DOM |
+| **[willUpdateProps](#willupdatepropsnextprops)** | async, before props update                            |
+| **[willPatch](#willpatch)**                      | just before the DOM is patched                        |
+| **[patched](#patchedsnapshot)**                  | just after the DOM is patched                         |
+| **[willUnmount](#willunmount)**                  | just before removing component from DOM               |
 
 Notes:
 
@@ -180,7 +186,7 @@ Notes:
   then on children, and `[Xed]` are called in the reverse order: first children,
   then parent.
 - no hook method should ever be called manually. They are supposed to be
-called by the owl framework whenever it is required.
+  called by the owl framework whenever it is required.
 
 #### `constructor(parent, props)`
 
@@ -204,7 +210,6 @@ implemented in most cases:
 
 ```javascript
 class ClickCounter extends owl.Component {
-  template = "click-counter";
   state = { value: 0 };
 
   ...
@@ -218,7 +223,7 @@ perform some action before the initial rendering of a component.
 
 It will be called exactly once before the initial rendering. It is useful
 in some cases, for example, to load external assets (such as a JS library)
-before the widget is rendered. Another use case is to load data from a server.
+before the component is rendered. Another use case is to load data from a server.
 
 ```javascript
   async willStart() {
@@ -230,7 +235,7 @@ At this point, the component is not yet rendered. Note that a slow `willStart` m
 interface. Therefore, some care should be made to make this method as
 fast as possible.
 
-The widget rendering will take place after `willStart` is completed.
+The component rendering will take place after `willStart` is completed.
 
 #### `mounted()`
 
@@ -275,8 +280,8 @@ scrollbar.
 
 Note that modifying the state object is not allowed here. This method is called just
 before an actual DOM patch, and is only intended to be used to save some local
-DOM state.  Also, it will not be called if the widget is not in the DOM (this can
-happen with widgets with `t-keepalive`).
+DOM state. Also, it will not be called if the component is not in the DOM (this can
+happen with components with `t-keepalive`).
 
 The return value of this method will be given as the first argument of the
 corresponding `patched` call.
@@ -288,12 +293,12 @@ likely via a change in its state/props or environment).
 
 This method is not called on the initial render. It is useful to interact
 with the DOM (for example, through an external library) whenever the
-component was patched.  Note that this hook will not be called if the widget is
-not in the DOM (this can happen with widgets with `t-keepalive`).
+component was patched. Note that this hook will not be called if the compoent is
+not in the DOM (this can happen with components with `t-keepalive`).
 
 The `snapshot` parameter is the result of the previous `willPatch` call.
 
-Updating the widget state in this hook is possible, but not encouraged.
+Updating the compoent state in this hook is possible, but not encouraged.
 One need to be careful, because updates here will cause rerender, which in
 turn will cause other calls to patched. So, we need to be particularly
 careful at avoiding endless cycles.
@@ -312,5 +317,680 @@ the DOM. This is a good place to remove some listeners, for example.
   }
 ```
 
-This is the opposite method of `mounted`. The `willUnmount` method will be
-called in reverse order: first the children, then the parents.
+This is the opposite method of `mounted`.
+
+### Root Component
+
+Most of the time, an Owl component will be created automatically by a tag (or the `t-component`
+directive) in a template. There is however an obvious exception: the root component
+of an Owl application has to be created manually:
+
+```js
+class App extends owl.Component { ... }
+
+const qweb = new owl.QWeb(TEMPLATES);
+const env = { qweb: qweb };
+const app = new App(env);
+app.mount(document.body);
+```
+
+The root component needs an environment.
+
+### Environment
+
+In Owl, an environment is an object with a `qweb` key, which has to be a
+[QWeb](qweb.md) instance. This qweb instance will be used to render everything.
+
+The environment is meant to contain (mostly) static global information and
+methods for the whole application. For example, settings keys (`mode` to determine
+if we are in desktop or mobile mode, or `theme`: dark or light), `rpc` methods,
+session information, ...
+
+The environment will be given to each child, unchanged, in the `env` property.
+This can be very useful to share common information/methods. For example, all
+rpcs can be made through a `rpc` method in the environment. This makes it very
+easy to test a component.
+
+Updating the environment is not as simple as changing a component's state: its
+content is not observed, so updates will not be reflected immediately in the
+user interface.  There is however a mechanism to force root widgets to rerender
+themselves whenever the environment is modified: one only needs to trigger the
+`update` event on the QWeb instance.  For example, a responsive environment
+could be programmed like this:
+
+```js
+function setupResponsivePlugin(env) {
+    const isMobile = () => window.innerWidth <= 768;
+    env.isMobile = isMobile();
+    const updateEnv = owl.utils.debounce(() => {
+        if (env.isMobile !== isMobile()) {
+            env.isMobile = !env.isMobile;
+            env.qweb.trigger('update');
+        }
+    }, 15);
+    window.addEventListener("resize", updateEnv);
+}
+```
+
+### Composition
+
+The example above shows a QWeb template with a sub component. In a template,
+components are declared with a tagname corresponding to the class name. It has
+to be capitalized.
+
+```xml
+<div t-name="ParentComponent">
+  <span>some text</span>
+  <MyComponent info="13" />
+</div>
+```
+
+```js
+class ParentComponent extends owl.Component {
+    components = { MyComponent: MyComponent};
+    ...
+}
+```
+
+In this example, the `ParentComponent`'s template creates a component `MyComponent` just
+after the span. The `info` key will be added to the subcomponent's `props`. Each
+`props` is a string which represents a javascript (QWeb) expression, so it is
+dynamic. If it is necessary to give a string, this can be done by quoting it:
+`someString="'somevalue'"`.
+
+Note that the rendering context for the template is the component itself. This means
+that the template can access `state`, `props`, `env`, or any methods defined in the component.
+
+```xml
+<div t-name="ParentComponent">
+    <ChildComponent count="state.val" />
+</div>
+```
+
+```js
+class ParentComponent {
+  components = { ChildComponent };
+  state = { val: 4 };
+}
+```
+
+Whenever the template is rendered, it will automatically create the subcomponent
+`ChildComponent` at the correct place. It needs to find the reference to the
+actual component class in the special `components` key, or the class registered in
+QWeb's global registry (see `register` function of QWeb). It first looks inside
+the local `components` key, then fallbacks on the global registry.
+
+_Props_: In this example, the child component will receive the object `{count: 4}` in its
+constructor. This will be assigned to the `props` variable, which can be accessed
+on the component (and also, in the template). Whenever the state is updated, then
+the sub component will also be updated automatically.
+
+Note that there are some restrictions on prop names: `class`, `style` and any
+string which starts with `t-` are not allowed.
+
+The `t-component` directive can also be used to accept dynamic values with string interpolation (like the [`t-attf-`](qweb.md#dynamic-attributes) directive):
+
+```xml
+<div t-name="ParentComponent">
+    <t t-component="ChildComponent{{id}}" />
+</div>
+```
+
+```js
+class ParentComponent {
+  components = { ChildComponent1, ChildComponent2 };
+  state = { id: 1 };
+}
+```
+
+**CSS and style:** there is some specific support to allow the parent to declare
+additional css classes or style for the sub component: css declared in `class`, `style`, `t-att-class` or `t-att-style` will be added to the
+root component element.
+
+```xml
+<div t-name="ParentComponent">
+  <MyComponent class="someClass" style="font-weight:bold;" info="13" />
+</div>
+```
+
+Warning: there is a small caveat with dynamic class attributes: since Owl needs
+to be able to add/remove proper classes whenever necessary, it needs to be aware
+of the possible classes. Otherwise, it will not be able to make the difference
+between a valid css class added by the component, or some custom code, and a
+class that need to be removed. This is why we only support the explicit syntax
+with a class object:
+
+```xml
+<MyComponent t-att-class="{a: state.flagA, b: state.flagB}" />
+```
+
+### Event Handling
+
+In a component's template, it is useful to be able to register handlers on some
+elements to some specific events. This is what makes a template _alive_. There
+are four different use cases.
+
+1. Register an event handler on a DOM node (_pure_ DOM event)
+2. Register an event handler on a component (_pure_ DOM event)
+3. Register an event handler on a DOM node (_business_ DOM event)
+4. Register an event handler on a component (_business_ DOM event)
+
+A _pure_ DOM event is directly triggered by a user interaction (e.g. a `click`).
+
+```xml
+<button t-on-click="someMethod">Do something</button>
+```
+
+This will be roughly translated in javascript like this:
+
+```js
+button.addEventListener("click", component.someMethod.bind(component));
+```
+
+The suffix (`click` in this example) is simply the name of the actual DOM
+event.
+
+A _business_ DOM event is triggered by a call to `trigger` on a component.
+
+```xml
+<MyComponent t-on-menu-loaded="someMethod" />
+```
+
+```js
+ class MyComponent {
+     someWhere() {
+         const payload = ...;
+         this.trigger('menu-loaded', payload);
+     }
+ }
+```
+
+The call to `trigger` generates a [_CustomEvent_](https://developer.mozilla.org/docs/Web/Guide/Events/Creating_and_triggering_events)
+of type `menu-loaded` and dispatches it on the component's DOM element
+(`this.el`). The event bubbles and is cancelable. The parent component listening
+to event `menu-loaded` will receive the payload in its `someMethod` handler
+(in the `detail` property of the event), whenever the event is triggered.
+
+```js
+ class ParentComponent {
+     someMethod(ev) {
+         const payload = ev.detail;
+         ...
+     }
+ }
+```
+
+By convention, we use KebabCase for the name of _business_ events.
+
+In order to remove the DOM event details from the event handlers (like calls to
+`event.preventDefault`) and let them focus on data logic, _modifiers_ can be
+specified as additional suffixes of the `t-on` directive.
+
+| Modifier   | Description                                                       |
+| ---------- | ----------------------------------------------------------------- |
+| `.stop`    | calls `event.stopPropagation()` before calling the method         |
+| `.prevent` | calls `event.preventDefault()` before calling the method          |
+| `.self`    | calls the method only if the `event.target` is the element itself |
+
+```xml
+<button t-on-click.stop="someMethod">Do something</button>
+```
+
+Note that modifiers can be combined (ex: `t-on-click.stop.prevent`), and that
+the order may matter. For instance `t-on-click.prevent.self` will prevent all
+clicks while `t-on-click.self.prevent` will only prevent clicks on the element
+itself.
+
+The `t-on` directive also allows to prebind some arguments. For example,
+
+```xml
+<button t-on-click="someMethod(expr)">Do something</button>
+```
+
+Here, `expr` is a valid Owl expression, so it could be `true` or some variable
+from the rendering context.
+
+### Form Input Bindings
+
+It is very common to need to be able to read the value out of an html `input` (or
+`textarea`, or `select`) in order to use it (note: it does not need to be in a
+form!). A possible way to do this is to do it by hand:
+
+```js
+class Form extends owl.Component {
+  state = { text: "" };
+
+  _updateInputValue(event) {
+    this.state.text = event.target.value;
+  }
+}
+```
+
+```xml
+<div>
+  <input t-on-input="_updateInputValue" />
+  <span t-esc="state.text" />
+</div>
+```
+
+This works. However, this requires a little bit of _plumbing_ code. Also, the
+plumbing code is slightly different if you need to interact with a checkbox,
+or with radio buttons, or with select tags.
+
+To help with this situation, Owl has a builtin directive `t-model`: its value
+is the (top-level) name in the state object. With the `t-model` directive, we
+can write a shorter code, equivalent to the previous example:
+
+```js
+class Form extends owl.Component {
+  state = { text: "" };
+}
+```
+
+```xml
+<div>
+  <input t-model="text" />
+  <span t-esc="state.text" />
+</div>
+```
+
+The `t-model` directive works with `<input>`, `<input type="checkbox">`,
+`<input type="radio">`, `<textarea>` and `<select>`:
+
+```xml
+<div>
+    <div>Text in an input: <input t-model="someVal"/></div>
+    <div>Textarea: <textarea t-model="otherVal"/></div>
+    <div>Boolean value: <input type="checkbox" t-model="someFlag"/></div>
+    <div>Selection:
+        <select t-model="color">
+            <option value="">Select a color</option>
+            <option value="red">Red</option>
+            <option value="blue">Blue</option>
+        </select>
+    </div>
+    <div>
+        Selection with radio buttons:
+        <span>
+            <input type="radio" name="color" id="red" value="red" t-model="color"/>
+            <label for="red">Red</label>
+        </span>
+        <span>
+            <input type="radio" name="color" id="blue" value="blue" t-model="color" />
+            <label for="blue">Blue</label>
+        </span>
+    </div>
+</div>
+```
+
+Like event handling, the `t-model` directive accepts some modifiers:
+
+| Modifier  | Description                                                          |
+| --------- | -------------------------------------------------------------------- |
+| `.lazy`   | update the value on the `change` event (default is on `input` event) |
+| `.number` | tries to parse the value to a number (using `parseFloat`)            |
+| `.trim`   | trim the resulting value                                             |
+
+For example:
+
+```xml
+<input t-model.lazy="someVal" />
+```
+
+These modifiers can be combined. For instance, `t-model.lazy.number` will only
+update a number whenever the change is done.
+
+Note: the online playground has an example to show how it works.
+
+### `t-key` Directive
+
+Even though Owl tries to be as declarative as possible, some DOM state is still
+locked inside the DOM: for example, the scrolling state, the current user selection,
+the focused element or the state of an input. This is why we use a virtual dom
+algorithm to keep the actual DOM node as much as possible. However, this is
+sometimes not enough, and we need to help Owl decide if an element is actually
+the same, or is different. The `t-key` directive is used to give an identity to an element.
+
+There are three main use cases:
+
+- _elements in a list_:
+
+  ```xml
+    <span t-foreach="todos" t-as="todo" t-key="todo.id">
+        <t t-esc="todo.text" />
+    </span>
+  ```
+
+- _`t-if`/`t-else`_
+
+- _animations_: give a different identity to a component. Ex: thread id with
+  animations on add/remove message.
+
+### `t-mounted` Directive
+
+The `t-mounted` directive allows to register a callback to execute whenever the node
+is inserted into the DOM.
+
+```xml
+<div><input t-ref="someInput" t-mounted="focusMe"/></div>
+```
+
+```js
+class MyComponent extends owl.Component {
+    ...
+    focusMe() {
+        this.refs.someInput.focus();
+    }
+}
+```
+
+### Semantics
+
+We give here an informal description of the way components are created/updated
+in an application. Here, ordered lists describe actions that are executed
+sequentially, bullet lists describe actions that are executed in parallel.
+
+**Scenario 1: initial rendering** Imagine we want to render the following component tree:
+
+```
+        A
+       / \
+      B   C
+         / \
+        D   E
+```
+
+Here is what happen whenever we mount the root
+component (with some code like `app.mount(document.body)`).
+
+1. `willStart` is called on `A`
+
+2. when it is done, template `A` is rendered.
+
+   - component `B` is created
+     1. `willStart` is called on `B`
+     2. template `B` is rendered
+   - component `C` is created
+     1. `willStart` is called on `C`
+     2. template `C` is rendered
+        - component `D` is created
+          1. `willStart` is called on `D`
+          2. template `D` is rendered
+        - component `E` is created
+          1. `willStart` is called on `E`
+          2. template `E` is rendered
+
+3. component `A` is patched into a detached DOM element. This will create the actual
+   component `A` DOM structure. The patching process will cause recursively the
+   patching of the `B`, `C`, `D` and `E` DOM trees. (so the actual full DOM tree is created
+   in one pass)
+
+4. the component `A` root element is actually appended to `document.body`
+
+5. The method `mounted` is called recursively on all components in the following
+   order: `B`, `D`, `E`, `C`, `A`.
+
+**Scenario 2: rerendering a component**. Now, let's assume that the user clicked on some
+button in `C`, and this results in a state update, which is supposed to:
+
+- update `D`,
+- remove `E`,
+- add new component `F`.
+
+So, the component tree should look like this:
+
+```
+        A
+       / \
+      B   C
+         / \
+        D   F
+```
+
+Here is what Owl will do:
+
+1. because of a state change, the method `render` is called on `C`
+2. template `C` is rendered again
+
+   - component `D` is updated:
+     1. hook `willUpdateProps` is called on `D` (async)
+     2. template `D` is rerendered
+   - component `F` is created:
+     1. hook `willStart` is called on `E` (async)
+     2. template `F` is rendered
+
+3. `willPatch` hooks are called recursively on components `C`, `D` (not on `F`,
+   because it is not mounted yet)
+
+4. component `C` is patched, which will cause recursively:
+
+   2. `willUnmount` hook on `E`, then destruction of `E`,
+   3. (initial) patching of `F`, then hook `mounted` is called on `F`
+
+5. patching of `D`
+
+6. `patched` hooks are called on `D`, `C`
+
+### Props Validation
+
+As an application becomes complex, it may be quite unsafe to define props in an informal way. This leads to two issues:
+
+- hard to tell how a component should be used, by looking at its code.
+- unsafe, it is easy to send wrong props into a component, either by refactoring a component, or one of its parent.
+
+A props type system would solve both issues, by describing the types and shapes
+of the props. Here is how it works in Owl:
+
+- `props` key is a static key (so, different from `this.props` in a component instance)
+- it is optional: it is ok for a component to not define a `props` key.
+- props are validated whenever a component is created/updated
+- props are only validated in `dev` mode (see [tooling page](tooling.md#development-mode))
+- if a key does not match the description, an error is thrown
+- it only validates keys defined in (static) `props`. Additional keys in (component) `props` are not validated.
+
+For example:
+
+```js
+class ComponentA extends owl.Component {
+    static props = ['id', 'url'];
+
+    ...
+}
+
+class ComponentB extends owl.Component {
+  static props = {
+    count: {type: Number},
+    messages: {
+      type: Array,
+      element: {type: Object, shape: {id: Boolean, text: 'string' }
+    },
+   date: Date,
+   combinedVal: [Number, Boolean]
+  };
+
+  ...
+}
+```
+
+- it is an object or a list of strings
+- a list of strings is a simplified props definition, which only lists the name
+  of the props.
+- all props are by default required, unless they are defined with `optional: true`
+  (in that case, validation is only done if there is a value)
+- valid types are: `Number, String, Boolean, Object, Array, Date, Function`, and all
+  constructor functions (so, if you have a `Person` class, it can be used as a type)
+- arrays are homogeneous (all elements have the same type/shape)
+
+For each key, a `prop` definition is either a constructor, a list of constructors, or an object:
+
+- a constructor: this should describe the type, for example: `id: Number` describe
+  the props `id` as a number
+- 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.
+- an object. This makes it possible to have more expressive definition. The following sub keys are then allowed:
+  - `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. It is optional (not set means that we only validate the array, not its elements),
+  - `shape`: if the type was `Object`, then the `shape` key describes the interface of the object. It is optional (not set means that we only validate the object, not its elements)
+
+Examples:
+
+```js
+  // only the existence of those 3 keys is documented
+  static props = ['message', 'id', 'date'];
+```
+
+```js
+  static props = {
+    messageIds: {type: Array, element: Number},  // list of number
+    otherArr: {type: Array},   // just array. no validation is made on sub elements
+    otherArr2: Array,   // same as otherArr
+    someObj: {type: Object},  // just an object, no internal validation
+    someObj2: {
+      type: Object,
+      shape: {
+        id: Number,
+        name: {type: String, optional: true},
+        url: String
+      ]},    // object, with keys id (number), name (string, optional) and url (string)
+    someFlag: Boolean,     // a boolean, mandatory (even if `false`)
+    someVal: [Boolean, Date]   // either a boolean or a date
+  };
+```
+
+### References
+
+The `t-ref` directive helps a component keep reference to some inside part of it.
+Like the `t-on` directive, it can work either on a DOM node, or on a component:
+
+```xml
+<div>
+    <div t-ref="someDiv"/>
+    <SubComponent t-ref="someComponent"/>
+</div>
+```
+
+In this example, the component will be able to access the `div` and the component
+inside the special `refs` variable:
+
+```js
+this.refs.someDiv;
+this.refs.someComponent;
+```
+
+This is useful for various usecases: for example, integrating with an external
+library that needs to render itself inside an actual DOM node. Or for calling
+some method on a sub component.
+
+Note: if used on a component, the reference will be set in the `refs`
+variable between `willPatch` and `patched`.
+
+The `t-ref` directive also accepts dynamic values with string interpolation
+(like the [`t-attf-`](qweb.md#dynamic-attributes) and
+`t-component` directives). For example, if we have
+`id` set to 44 in the rendering context,
+
+```xml
+<div t-ref="component_{{id}}"/>
+```
+
+```js
+this.refs.component_44;
+```
+
+### Slots
+
+To make generic components, it is useful to be able for a parent component to _inject_
+some sub template, but still be the owner. For example, a generic dialog component
+will need to render some content, some footer, but with the parent as the
+rendering context.
+
+This is what _slots_ are for.
+
+```xml
+<div t-name="Dialog" class="modal">
+  <div class="modal-title"><t t-esc="props.title"/></div>
+  <div class="modal-content">
+    <t t-slot="content"/>
+  </div>
+  <div class="modal-footer">
+    <t t-slot="footer"/>
+  </div>
+</div>
+```
+
+Slots are defined by the caller, with the `t-set` directive:
+
+```xml
+<div t-name="SomeComponent">
+  <div>some component</div>
+  <Dialog title="Some Dialog">
+    <t t-set="content">
+      <div>hey</div>
+    </t>
+    <t t-set="footer">
+      <button t-on-click="doSomething">ok</button>
+    </t>
+  </Dialog>
+</div>
+```
+
+In this example, the component `Dialog` will render the slots `content` and `footer`
+with its parent as rendering context. This means that clicking on the button
+will execute the `doSomething` method on the parent, not on the dialog.
+
+Default slot: the first element inside the component which is not a named slot will
+be considered the `default` slot. For example:
+
+```xml
+<div t-name="Parent">
+  <Child>
+    <span>some content</span>
+  </Child>
+</div>
+
+<div t-name="Child">
+  <t t-slot="default"/>
+</div>
+```
+
+### Asynchronous Rendering
+
+Working with asynchronous code always adds a lot of complexity to a system. Whenever
+different parts of a system are active at the same time, one needs to think
+carefully about all possible interactions. Clearly, this is also true for Owl
+components.
+
+There are two different common problems with Owl asynchronous rendering model:
+
+- any component can delay the rendering (initial and subsequent) of the whole
+  application
+- for a given component, there are two independant situations that will trigger an
+  asynchronous rerendering: a change in the state, or a change in the props.
+  These changes may be done at different times, and Owl has no way of knowing
+  how to reconcile the resulting renderings.
+
+Here are a few tips on how to work with asynchronous components:
+
+1. Minimize the use of asynchronous components!
+2. Maybe move the asynchronous logic in a store, which then triggers (mostly)
+   synchronous renderings
+3. Lazy loading external libraries is a good use case for async rendering. This
+   is mostly fine, because we can assume that it will only takes a fraction of a
+   second, and only once (see `owl.utils.loadJS`)
+4. For all the other cases, the `t-asyncroot` directive (to use alongside
+   `t-component`) is there to help you. When this directive is met, a new rendering
+   sub tree is created, such that the rendering of that component (and its
+   children) is not tied to the rendering of the rest of the interface. It can
+   be used on an asynchronous component, to prevent it from delaying the
+   rendering of the whole interface, or on a synchronous one, such that its
+   rendering isn't delayed by other (asynchronous) components. Note that this
+   directive has no effect on the first rendering, but only on subsequent ones
+   (triggered by state or props changes).
+
+   ```xml
+   <div t-name="ParentComponent">
+     <SyncChild />
+     <AsyncChild t-asyncroot="1"/>
+   </div>
+   ```

doc/event_bus.md

@@ -0,0 +1,27 @@
+# 🦉 Event Bus 🦉
+
+It is sometimes useful to use a `Bus` to communicate informations between various
+parts of the code. Owl has a very simple bus class, which manages subscriptions,
+triggering events, and callbacks.
+
+```js
+const bus = new owl.EventBus();
+
+bus.on("some-event", null, function(...args) {
+  console.log(...args);
+});
+
+bus.trigger("some-event", 1, 2, 3);
+// [1,2,3] will be logged to the console
+```
+
+Its API is:
+
+| Method                           | Description                       |
+| -------------------------------- | --------------------------------- |
+| `on(eventType, owner, callback)` | add a listener                    |
+| `off(eventType, owner)`          | remove all listeners for an owner |
+| `trigger(eventType, ...args)`    | trigger an event                  |
+| `clear`                          | remove all subscriptions          |
+
+Note that the [`Store`](store.md) is an example of an `EventBus`.

doc/observer.md

@@ -20,35 +20,31 @@ obj.a.b = 2;
 ## Technical Limitations
 
 Since the observer uses getters and setters, it is actually unable to react to
-changes in two situations:
+changes in three situations:
 
-- adding a key to an object:
+- adding a key to an object
+- deleting a key from an object
+- modifying an array by setting a new value at a given index
 
-  ```javascript
-  const observer = new owl.Observer();
-  const obj = { a: 1 };
-  observer.observe(obj);
-  obj.b = 2; // will do nothing
-  ```
+In those situations, we need a way to tell the observer that something happened.
+This can be done by using the `set` and `delete` (only for objects) static
+methods of the `Observer`.
 
-  In that case, we need a way to tell the observer that something happened.
-  This can be done by using the `set` method:
+```javascript
+const observer = new owl.Observer();
+const obj = { a: 1 };
+observer.observe(obj);
+obj.b = 2; // won't notify the change
+owl.Observer.set(obj, "b", 2); // will notify the change
 
-  ```javascript
-  observer.set(obj, "b", 2);
-  ```
+delete obj.b; // won't notify the change
+owl.Observer.delete(obj, "b"); // will notify the change
+```
 
-- modifying an array by setting a new value at a given index:
-
-  ```javascript
-  const observer = new owl.Observer();
-  const obj = { todos: [{ id: 1, text: "todo" }] };
-  observer.observe(obj);
-  obj[0] = { id: 2, text: "othertodo" }; // will do nothing, and obj[0] is not observed
-  ```
-
-  In that case, the solution is the same, we can simply use the `set` method:
-
-  ```javascript
-  observer.set(obj, 0, { id: 2, text: "othertodo" });
-  ```
+```javascript
+const observer = new owl.Observer();
+const arr = ["a"];
+observer.observe(arr);
+arr[0] = "b"; // won't notify the change
+owl.Observer.set(arr, 0, "b"); // will notify the change
+```

doc/quick_start.md

@@ -1,6 +1,6 @@
 # 🦉 Quick Start 🦉
 
-## Static server
+## Static Server
 
 Let us assume that we have a static server running somewhere. We could then
 simply add an html page with a few extra files.
@@ -58,16 +58,16 @@ To build an application (or a sub-part of an application), we need two things:
   need. In practice, it could context some user session information, some
   configuration keys (for example, isMobile = true/false if we are in mobile mode).
 
-- a description of the user interface: there should be a root widget, which can
-  have sub widgets
+- a description of the user interface: there should be a root component, which can
+  have sub components
 
 Here are a few steps that we may take to get started:
 
 - get the templates
 - create a qweb engine, with the templates
 - create an environment
-- create an instance of the root widget
-- mount the root widget to a DOM element
+- create an instance of the root component
+- mount the root component to a DOM element
 
 Let us now add the javascript to make it work, in `app.js`:
 

doc/qweb.md

@@ -3,44 +3,237 @@
 ## Content
 
 - [Overview](#overview)
-- [QWeb Specification](#qweb-specification)
-    - [Static html nodes](#static-html-nodes)
-    - [`t-esc` directive](#t-esc-directive)
-    - [`t-raw` directive](#t-raw-directive)
-    - [`t-set` directive](#t-set-directive)
-    - [`t-if` directive](#t-if-directive)
-    - [Expression evaluation](#expression-evaluation)
-    - [`t-att` directive (dynamic attributes)](#t-att-directive-dynamic-attributes)
-- [JS/OWL Specific Extensions](#jsowl-specific-extensions)
-    - [`t-on` directive](#t-on-directive)
-    - [Component: `t-widget`, `t-props`](#component-t-widget-t-props)
-    - [`t-ref` directive](#t-ref-directive)
-    - [`t-key` directive](#t-key-directive)
-    - [`t-transition` directive](#t-transition)
-    - [Debugging (`t-debug` and `t-log`)](#debugging-t-debug-and-t-log)
-    - [White spaces](#white-spaces)
-    - [Root nodes](#root-nodes)
+- [Directives](#directives)
+- [QWeb Engine](#qweb-engine)
+- [Reference](#reference)
+  - [White Spaces](#white-spaces)
+  - [Root Nodes](#root-nodes)
+  - [Expression Evaluation](#expression-evaluation)
+  - [Static html Nodes](#static-html-nodes)
+  - [Outputting Data](#outputting-data)
+  - [Setting Variables](#setting-variables)
+  - [Conditionals](#conditionals)
+  - [Dynamic Attributes](#dynamic-attributes)
+  - [Loops](#loops)
+  - [Rendering Sub Templates](#rendering-sub-templates)
+  - [Debugging](#debugging)
 
 ## Overview
 
 [QWeb](https://www.odoo.com/documentation/12.0/reference/qweb.html) is the primary templating engine used by Odoo. It is based on the XML format, and used
-mostly to generate html. In OWL, QWeb templates are compiled into functions that
-generate a virtual dom representation of the html.
+mostly to generate HTML. In OWL, QWeb templates are compiled into functions that
+generate a virtual dom representation of the HTML.
 
 Template directives are specified as XML attributes prefixed with `t-`, for instance `t-if` for conditionals, with elements and other attributes being rendered directly.
 
 To avoid element rendering, a placeholder element `<t>` is also available, which executes its directive but doesn’t generate any output in and of itself.
 
-The QWeb implementation in the OWL project is slightly different. It compiles
-templates into functions that output a virtual DOM instead of a string. This is
-necessary for the component system. In addition, it has a few extra directives
-(see [OWL Specific Extensions](#owlspecificextensions))
+```xml
+<div>
+    <span t-if="somecondition">Some string</span>
+    <ul t-else="1">
+        <li t-foreach="messages" t-as="message">
+            <t t-esc="message">
+        </li>
+    </ul>
+</div>
+```
 
+The QWeb class in the OWL project is an implementation of that specification
+with a few interesting points:
 
-## QWeb Specification
+- it compiles templates into functions that output a virtual DOM instead of a
+  string. This is necessary for the component system.
+- it has a few extra directives: `t-component`, `t-on`, ...
 
+## Directives
 
-### Static html nodes
+We present here a list of all standard QWeb directives:
+
+| Name                           | Description                                                  |
+| ------------------------------ | ------------------------------------------------------------ |
+| `t-esc`                        | [Outputting safely a value](#outputting-data)                |
+| `t-raw`                        | [Outputting value, without escaping](#outputting-data)       |
+| `t-set`, `t-value`             | [Setting variables](#setting-variables)                      |
+| `t-if`, `t-elif`, `t-else`,    | [conditionally rendering](#conditionals)                     |
+| `t-foreach`, `t-as`            | [Loops](#loops)                                              |
+| `t-att`, `t-attf-*`, `t-att-*` | [Dynamic attributes](#dynamic-attributes)                    |
+| `t-call`                       | [Rendering sub templates](#rendering-sub-templates)          |
+| `t-debug`, `t-log`             | [Debugging](#debugging)                                      |
+| `t-name`                       | [Defining a template (not really a directive)](#qweb-engine) |
+
+The component system in Owl requires additional directives, to express various
+needs. Here is a list of all Owl specific directives:
+
+| Name                                        | Description                                                                         |
+| ------------------------------------------- | ----------------------------------------------------------------------------------- |
+| `t-component`, `t-keepalive`, `t-asyncroot` | [Defining a sub component](component.md#composition)                                |
+| `t-ref`                                     | [Setting a reference to a dom node or a sub component](component.md#references)     |
+| `t-key`                                     | [Defining a key (to help virtual dom reconciliation)](component.md#t-key-directive) |
+| `t-on-*`                                    | [Event handling](component.md#event-handling)                                       |
+| `t-transition`                              | [Defining an animation](animations.md#css-transitions)                              |
+| `t-mounted`                                 | [Callback when a node or component is mounted](component.md#t-mounted-directive)    |
+| `t-slot`                                    | [Rendering a slot](component.md#slots)                                              |
+| `t-model`                                   | [Form input bindings](component.md#form-input-bindings)                             |
+
+## QWeb Engine
+
+This section is about the javascript code that implements the `QWeb` specification.
+Owl exports a `QWeb` class in `owl.QWeb`. To use it, it just needs to be
+instantiated:
+
+```js
+const qweb = new owl.QWeb();
+```
+
+It's API is quite simple:
+
+- **`constructor(data)`**: constructor. Takes an optional string to add initial
+  templates (see `addTemplates` for more information on format of the string).
+
+  ```js
+  const qweb = new owl.QWeb(TEMPLATES);
+  ```
+
+- **`addTemplate(name, xmlStr, allowDuplicate)`**: add a specific template.
+
+  ```js
+  qweb.addTemplate("mytemplate", "<div>hello</div>");
+  ```
+
+  If the optional `allowDuplicate` is set to `true`, then `QWeb` will simply return whenever a template is added for a second time.  Otherwise, `QWeb` will crash.
+
+- **`addTemplates(xmlStr)`**: add a list of templates (identified by `t-name`
+  attribute).
+
+  ```js
+  const TEMPLATES = `
+    <templates>
+      <div t-name="App" class="main">main</div>
+      <div t-name="OtherComponent">other component</div>
+    </templates>`;
+  qweb.addTemplates(TEMPLATES);
+  ```
+
+- **`render(name, context, extra)`**: renders a template. This returns a `vnode`,
+  which is a virtual representation of the DOM (see [vdom doc](vdom.md)).
+
+  ```js
+  const vnode = qweb.render("App", component);
+  ```
+
+- **`register(name, Component)`**: static function to register an OWL Component
+  to QWeb's global registry. Globally registered Components can be used in
+  templates (see the `t-component` directive). This is useful for commonly used
+  components accross the application.
+
+  ```js
+  class Dialog extends owl.Component { ... }
+  QWeb.register("Dialog", Dialog);
+
+  ...
+
+  class ParentComponent extends owl.Component { ... }
+  qweb.addTemplate("ParentComponent", "<div><Dialog/></div>");
+  ```
+
+In some way, a `QWeb` instance is the core of an Owl application. It is the only
+mandatory element of an [environment](component.md#environment). As such, it
+has an extra responsability: it can act as an event bus for internal communication
+between Owl classes. This is the reason why `QWeb` actually extends [EventBus](event_bus.md).
+
+## Reference
+
+We define in this section the specification of how `QWeb` templates should be
+rendered. Note that we only document here the standard QWeb specification. Owl
+specific extensions are documented in various other parts of the documentation.
+
+### White Spaces
+
+White spaces in a templates are handled in a special way:
+
+- consecutive whitespaces are always condensed to a single whitespace
+- if a whitespace-only text node contains a linebreak, it is ignored
+- the previous rules do not apply if we are in a `<pre>` tag
+
+### Root Nodes
+
+For many reasons, Owl QWeb templates should have a single root node. More
+precisely, the result of a template rendering should have a single root node:
+
+```xml
+<!–– not ok: two root nodes ––>
+<t>
+    <div>foo</div>
+    <div>bar</div>
+</t>
+
+<!–– ok: result has one single root node ––>
+<t>
+    <div t-if="someCondition">foo</div>
+    <span t-else="1">bar</span>
+</t>
+```
+
+Extra root nodes will actually be ignored (even though they will be rendered
+in memory).
+
+Note: this does not apply to subtemplates (see the `t-call` directive). In that
+case, they will be inlined in the main template, and can actually have many
+root nodes.
+
+### Expression Evaluation
+
+QWeb expressions are strings that will be processed at compile time. Each variable in
+the javascript expression will be replaced by a lookup in the context (so, the
+component). For example, `a + b.c(d)` will be converted into:
+
+```js
+context["a"] + context["b"].c(context["d"]);
+```
+
+It is useful to explain the various rules that applies on these expressions:
+
+1. it should be a simple expression which returns a value. It cannot be a statement.
+
+   ```xml
+   <div><p t-if="1 + 2 === 3">ok</p></div>
+   ```
+
+   is valid, but the following is not valid:
+
+   ```xml
+   <div><p t-if="console.log(1)">NOT valid</p></div>
+   ```
+
+2. it can use anything in the rendering context (typically, the component):
+
+   ```xml
+   <p t-if="user.birthday === today()">Happy bithday!</p>
+   ```
+
+   is valid, and will read the `user` object from the context, and call the
+   `today` function.
+
+3. it can use a few special operators to avoid using symbols such as `<`, `>`,
+   `&` or `|`. This is useful to make sure that we still write valid XML.
+
+   | Word  | will be replaced by |
+   | ----- | ------------------- |
+   | `and` | `&&`                |
+   | `or`  | `\|\|`              |
+   | `gt`  | `>`                 |
+   | `gte` | `>=`                |
+   | `lt`  | `<`                 |
+   | `lte` | `<=`                |
+
+   So, one can write this:
+
+   ```xml
+   <div><p t-if="10 + 2 gt 5">ok</p></div>
+   ```
+
+### Static Html Nodes
 
 Normal, regular html nodes are rendered into themselves:
 
@@ -48,7 +241,7 @@ Normal, regular html nodes are rendered into themselves:
   <div>hello</div> <!–– rendered as itself ––>
 ```
 
-### `t-esc` directive
+### Outputting Data
 
 The `t-esc` directive is necessary whenever you want to add a dynamic text
 expression in a template. The text is escaped to avoid security issues.
@@ -63,14 +256,12 @@ rendered with the value `value` set to `42` in the rendering context yields:
 <p>42</p>
 ```
 
-### `t-raw` directive
-
 The `t-raw` directive is almost the same as `t-esc`, but without the escaping.
 This is mostly useful to inject a raw html string somewhere. Obviously, this
 is unsafe to do in general, and should only be used for strings known to be safe.
 
 ```xml
-<p><t t-esc="value"/></p>
+<p><t t-raw="value"/></p>
 ```
 
 rendered with the value `value` set to `<span>foo</span>` in the rendering context yields:
@@ -79,7 +270,7 @@ rendered with the value `value` set to `<span>foo</span>` in the rendering conte
 <p><span>foo</span></p>
 ```
 
-### `t-set` directive
+### Setting Variables
 
 QWeb allows creating variables from within the template, to memoize a computation (to use it multiple times), give a piece of data a clearer name, ...
 
@@ -111,7 +302,7 @@ This is done via the `t-set` directive, which takes the name of the variable to
 The `t-set` directive acts like a regular variable in most programming language.
 It is lexically scoped (inner nodes are sub scopes), can be shadowed, ...
 
-### `t-if` directive
+### Conditionals
 
 The `t-if` directive is useful to conditionally render something. It evaluates
 the expression given as attribute value, and then acts accordingly.
@@ -161,52 +352,7 @@ Extra conditional branching directives `t-elif` and `t-else` are also available:
 </div>
 ```
 
-### Expression evaluation
-
-It is useful to explain the various rules that applies on QWeb expressions. These
-expressions are strings that will be converted to a javascript expression at
-compile time.
-
-1. it should be a simple expression which returns a value. It cannot be a statement.
-
-   ```xml
-   <div><p t-if="1 + 2 === 3">ok</p></div>
-   ```
-
-   is valid, but the following is not valid:
-
-   ```xml
-   <div><p t-if="console.log(1)">NOT valid</p></div>
-   ```
-
-2. it can use anything in the rendering context:
-
-   ```xml
-   <p t-if="user.birthday == today()">Happy bithday!</p>
-   ```
-
-   is valid, and will read the `user` object from the context, and call the
-   `today` function.
-
-3. it can use a few special operators to avoid using symbols such as `<`, `>`,
-   `&` or `|`. This is useful to make sure that we still write valid XML.
-
-   | Word  | will be replaced by |
-   | ----- | ------------------- |
-   | `and` | `&&`                |
-   | `or`  | `\|\|`                |
-   | `gt`  | `>`                 |
-   | `gte` | `>=`                |
-   | `lt`  | `<`                 |
-   | `lte` | `<=`                |
-
-   So, one can write this:
-
-   ```xml
-   <div><p t-if="10 + 2 gt 5">ok</p></div>
-   ```
-
-### `t-att` directive (dynamic attributes)
+### Dynamic Attributes
 
 One can use the `t-att-` directive to add dynamic attributes. Its main use is to
 evaluate an expression (at rendering time) and bind an attribute to its result:
@@ -214,7 +360,7 @@ evaluate an expression (at rendering time) and bind an attribute to its result:
 For example, if we have `id` set to 32 in the rendering context,
 
 ```xml
-<div t-att-data-action-id="id"/>  <!-- result: <div data-action-id="32"></div> -->
+<div t-att-data-action-id="id"/> <!-- result: <div data-action-id="32"></div> -->
 ```
 
 If an expression evaluates to a falsy value, it will not be set at all:
@@ -223,86 +369,128 @@ If an expression evaluates to a falsy value, it will not be set at all:
 <div t-att-foo="false"/>  <!-- result: <div></div> -->
 ```
 
-## JS/OWL Specific Extensions
-
-### `t-on` directive
-
-### Component: `t-widget`, `t-props`
-
-### `t-ref` directive
-
-### `t-key` directive
-
-Even though Owl tries to be as declarative as possible, some DOM state is still
-locked inside the DOM: for example, the scrolling state, the current user selection,
-the focused element or the state of an input. This is why we use a virtual dom
-algorithm to keep the actual DOM node as much as possible.  However, this is
-sometimes not enough, and we need to help Owl decide if an element is actually
-the same, or is different. The `t-key` directive is used to give an identity to an element.
-
-There are three main use cases:
-
-- *elements in a list*:
-  ```xml
-    <span t-foreach="todos" t-as="todo" t-key="todo.id">
-        <t t-esc="todo.text"/>
-    </span>
-  ```
-
-- *`t-if`/`t-else`*
-
-- *animations*: give a different identity to a component.  Ex: thread id with
-animations on add/remove message.
-
-### `t-transition` directive
-
-To perform useful transition effects, whenever an element appears or disappears,
-it is necessary to add/remove some css style or class at some precise moment in
-the lifetime of a node.  Since this is not easy to do by hand, Owl `t-transition`
-directive is there to help.
-
-Whenever a node has a `t-transition` directive, with a `name` value, the following
-will happen:
-
-At node creation:
-
-- the css classes `name-enter` and `name-enter-active` will be added before the
-  node is added to the DOM,
-- on the next animation frame: the css class `name-enter` will be removed and the
-  class `name-enter-to` will be added (so they can be used to trigger css
-  transition effects),
-- the css class `name-enter-active` will be removed whenever a css transition
-  ends.
-
-At node destruction:
-- the css classes `name-leave` and `name-leave-active` will be added before the
-  node is removed to the DOM,
-- the css class `name-leave` will be removed on the next animation frame (so it
-  can be used to trigger css transition effects),
-- the css class `name-leave-active` will be removed whenever a css transition
-  ends. Only then will the element be removed from the DOM.
-
-For example, a simple fade in/out effect can be done with this:
+There is another way to format a string attribute: the `t-attf-` directive. With
+it, you get string interpolation:
 
 ```xml
-<div>
-    <div t-if="state.flag" class="square" t-transition="fade">Hello</div>
+<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> -->
+```
+
+### Loops
+
+QWeb has an iteration directive `t-foreach` which take an expression returning the
+collection to iterate on, and a second parameter `t-as` providing the name to use
+for the current item of the iteration:
+
+```xml
+<t t-foreach="[1, 2, 3]" t-as="i">
+    <p><t t-esc="i"/></p>
+</t>
+```
+
+will be rendered as:
+
+```xml
+<p>1</p>
+<p>2</p>
+<p>3</p>
+```
+
+Like conditions, `t-foreach` applies to the element bearing the directive’s attribute, and
+
+```xml
+<p t-foreach="[1, 2, 3]" t-as="i">
+    <t t-esc="i"/>
+</p>
+```
+
+is equivalent to the previous example.
+
+`t-foreach` can iterate on an array (the current item will be the current value)
+or an object (the current item will be the current key).
+
+In addition to the name passed via t-as, `t-foreach` provides a few other
+variables for various data points (note: `$as` will be replaced by the name
+passed to `t-as`):
+
+- `$as_value`: the current iteration value, identical to `$as` for lists and
+  integers, but for objects, it provides the value (where `$as` provides the key)
+- `$as_index`: the current iteration index (the first item of the iteration has index 0)
+- `$as_first`: whether the current item is the first of the iteration
+  (equivalent to `$as_index == 0`)
+- `$as_last`: whether the current item is the last of the iteration
+  (equivalent to `$as_index + 1 == $as_size`), requires the iteratee’s size be
+  available
+
+These extra variables provided and all new variables created into the `t-foreach`
+are only available in the scope of the `t-foreach`. If the variable exists outside
+the context of the `t-foreach`, the value is copied at the end of the foreach
+into the global context.
+
+```xml
+<t t-set="existing_variable" t-value="False"/>
+<!-- existing_variable now False -->
+
+<p t-foreach="Array(3)" t-as="i">
+    <t t-set="existing_variable" t-value="True"/>
+    <t t-set="new_variable" t-value="True"/>
+    <!-- existing_variable and new_variable now True -->
+</p>
+
+<!-- existing_variable always True -->
+<!-- new_variable undefined -->
+```
+
+### Rendering Sub Templates
+
+QWeb templates can be used for top level rendering, but they can also be used
+from within another template (to avoid duplication or give names to parts of
+templates), using the `t-call` directive:
+
+```xml
+<div t-name="other-template">
+    <p><t t-value="var"/></p>
+</div>
+
+<div t-name="main-template">
+    <t t-set="var" t-value="owl"/>
+    <t t-call="other-template"/>
 </div>
 ```
 
-```css
-.fade-enter-active, .fade-leave-active {
-    transition: opacity .5s;
-}
-.fade-enter, .fade-leave-to {
-    opacity: 0;
-}
+will be rendered as `<div><p>owl</p></div>`. This example shows that the sub
+template is rendered with the execution context of the parent. The sub template
+is actually inlined in the main template, but in a sub scope: variables defined
+in the sub template do not escape.
+
+Sometimes, one might want to pass information to the sub template. In that case,
+the content of the body of the `t-call` directive is available as a special
+magic variable `0`:
+
+```xml
+<t t-name="other-template">
+    This template was called with content:
+    <t t-raw="0"/>
+</t>
+
+<div t-name="main-template">
+    <t t-call="other-template">
+        <em>content</em>
+    </t>
+</div>
 ```
 
-Note: you will find more information on animations in the [animation](doc/animations.md)
-documentation.
+will result in :
 
-### Debugging (`t-debug` and `t-log`)
+```xml
+<div>
+    This template was called with content:
+    <em>content</em>
+</div>
+```
+
+### Debugging
 
 The javascript QWeb implementation provides two useful debugging directives:
 
@@ -312,7 +500,7 @@ The javascript QWeb implementation provides two useful debugging directives:
 <t t-if="a_test">
     <t t-debug="">
 </t>
-````
+```
 
 will stop execution if the browser dev tools are open.
 
@@ -324,38 +512,3 @@ will stop execution if the browser dev tools are open.
 ```
 
 will print 42 to the console
-
-
-### White spaces
-
-White spaces in a templates are handled in a special way:
-
-- consecutive whitespaces are always condensed to a single whitespace
-- if a whitespace-only text node contains a linebreak, it is ignored
-- the previous rules do not apply if we are in a `<pre>` tag
-
-### Root nodes
-
-For many reasons, Owl QWeb templates should have a single root node.  More
-precisely, the result of a template rendering should have a single root node:
-
-```xml
-<!–– not ok: two root nodes ––>
-<t>
-    <div>foo</div>
-    <div>bar</div>
-</t>
-
-<!–– ok: result has one single root node ––>
-<t>
-    <div t-if="someCondition">foo</div>
-    <span t-else="1">bar</span>
-</t>
-```
-
-Extra root nodes will actually be ignored (even though they will be rendered
-in memory).
-
-Note: this does not apply to subtemplates (see the `t-call` directive).  In that
-case, they will be inlined in the main template, and can actually have many
-root nodes.

doc/readme.md

@@ -1,15 +1,21 @@
 # 🦉 OWL Documentation 🦉
 
-
 ## Reference
 
+- [Animations](animations.md)
 - [Component](component.md)
+- [Event Bus](event_bus.md)
+- [Observer](observer.md)
 - [QWeb](qweb.md)
 - [Store](store.md)
-- [Observer](observer.md)
+- [Utils](utils.md)
 - [Virtual DOM](vdom.md)
 
-## Miscellaneous
+## Learning Resources
+
 - [Quick Start](quick_start.md)
-- [Animations](animations.md)
+
+## Miscellaneous
+
 - [Comparison with React/Vue](comparison.md)
+- [Tooling](tooling.md)

doc/store.md

@@ -1,8 +1,258 @@
 # 🦉 Store 🦉
 
-Managing the state in an application is not an easy task. Many different
-architectures/designs/systems/... have been created. We propose here to use
-the idea of a central store.
+## Content
 
-- Store
-- connect
+- [Overview](#overview)
+- [Example](#example)
+- [Reference](#reference)
+  - [Public API](#public-api)
+  - [Mutations](#mutations)
+  - [Actions](#actions)
+  - [Getters](#getters)
+  - [Connecting a Component](#connecting-a-component)
+  - [Semantics](#semantics)
+  - [Good Practices](#good-practices)
+
+## Overview
+
+Managing the state in an application is not an easy task. In some cases, the
+state of an application can be part of the component tree, in a natural way.
+However, there are situations where some part of the state need to be displayed
+in various parts of the user interface, and then, it is not obvious which
+component should own which part of the state.
+
+Owl's solution to this issue is a centralized store. It is a class that owns
+some state, and let the developer update it in a structured way (through
+mutations and actions). Owl components can then connect to the store, and will
+be updated if necessary.
+
+Note: Owl's store is inspired by React Redux and VueX.
+
+## Example
+
+Here is what a simple store looks like:
+
+```js
+const actions = {
+  addTodo({ commit }, message) {
+    commit("addTodo", message);
+  }
+};
+
+const mutations = {
+  addTodo({ state }, message) {
+    const todo = {
+      id: state.nextId++,
+      message,
+      isCompleted: false
+    };
+    state.todos.push(todo);
+  }
+};
+
+const state = {
+  todos: [],
+  nextId: 1
+};
+
+const store = new owl.Store({ state, actions, mutations });
+store.on("update", () => console.log(store.state));
+
+// updating the state
+store.dispatch("addTodo", "fix all bugs");
+```
+
+## Reference
+
+The store is a simple [`owl.EventBus`](event_bus.md) that triggers `update` events whenever its
+state is changed. Note that these events are triggered only after a microtask
+tick, so only one event will be triggered for any number of state changes in a
+call stack.
+
+Also, it is important to mention that the state is observed (with an `owl.Observer`),
+which is the reason why it is able to know if it was changed. This implies that
+state changes need to be done carefully in some cases (adding a new key to an
+object, or modifying an array with the `arr[i] = newValue` syntax). See the
+[Observer](observer.md)'s documentation for more details.
+
+### Public API
+
+1. `constructor`
+2. `commit`
+3. `dispatch`
+
+### Mutations
+
+Mutations are the only way to modify the state. Changing the state outside a
+mutation is not allowed (and should throw an error). Mutations are synchronous.
+
+```js
+const mutations = {
+  setLoginState({ state }, loginState) {
+      state.loginState = loginState;
+  }
+};
+```
+
+Mutations are called with the `commit` method on the store, and can receive an arbitrary number of arguments.
+
+```js
+store.commit("setLoginState", "error");
+```
+
+### Actions
+
+Actions are used to coordinate state changes. It is also useful whenever some
+asynchronous logic is necessary. For example, fetching data should be done
+in an action.
+
+```js
+const actions = {
+  async login({ commit }, info) {
+    commit("setLoginState", "pending");
+    try {
+      const loginInfo = await doSomeRPC("/login/", info);
+      commit("setLoginState", loginInfo);
+    } catch {
+      commit("setLoginState", "error");
+    }
+  }
+};
+```
+
+Actions are called with the `dispatch` method on the store, and can receive an
+arbitrary number of arguments.
+
+```js
+store.dispatch("login", someInfo);
+```
+
+### Getters
+
+Usually, data contained in the store will be stored in a normalized way. For
+example,
+
+```js
+{
+    posts: [{id: 11, authorId: 4, content: 'Greetings'}],
+    authors: [{id: 4, name: 'John'}]
+}
+```
+
+However, the user interface will probably need some denormalized data like
+
+```js
+{id: 11, author: {id: 4, name: 'John'}, content: 'Greetings'}
+```
+
+This is what `getters` are for: they give a centralized way to process and
+transform the data contained in the store.
+
+```js
+const getters = {
+  getPost({ state }, id) {
+    const post = state.posts.find(p => p.id === id);
+    const author = state.authors.find(a => (a.id = post.id));
+    return {
+      id,
+      author,
+      content: post.content
+    };
+  }
+};
+
+// somewhere else
+const post = store.getters.getPost(id);
+```
+
+Getters take *at most* one argument.
+
+
+Note that getters are cached if they don't take any argument, or their argument
+is a string or a number.
+
+### Connecting a Component
+
+By default, an Owl `Component` is not connected to any store. The `connect`
+function is there to create sub Components that are connected versions of
+Components.
+
+```javascript
+const actions = {
+  increment({ commit }) {
+    commit("increment", 1);
+  }
+};
+const mutations = {
+  increment({ state }, val) {
+    state.counter += val;
+  }
+};
+const state = {
+  counter: 0
+};
+const store = new owl.Store({ state, actions, mutations });
+
+class Counter extends owl.Component {
+  increment() {
+    this.env.store.dispatch("increment");
+  }
+}
+function mapStoreToProps(state) {
+  return {
+    value: state.counter
+  };
+}
+const ConnectedCounter = owl.connect(Counter, mapStoreToProps);
+
+const counter = new ConnectedCounter({ store, qweb });
+```
+
+```xml
+<button t-name="Counter" t-on-click="increment">
+  Click Me! [<t t-esc="props.value"/>]
+</button>
+```
+
+The arguments of `connect` are:
+
+- `Counter`: an owl `Component` to connect
+- `mapStoreToProps`: a function that extracts the `props` of the Component
+  from the `state` of the `Store` and returns them as a dict
+- `options`: dictionary of optional parameters that may contain
+  - `getStore`: a function that takes the `env` in arguments and returns an
+    instance of `Store` to connect to (if not given, connects to `env.store`)
+  - `hashFunction`: the function to use to detect changes in the state (if not
+    given, generates a function that uses revision numbers, incremented at
+    each state change)
+  - `deep`: [only useful if no hashFunction is given] if false, only watch
+    for top level state changes (true by default)
+
+The `connect` function returns a sub class of the given `Component` which is
+connected to the `store`.
+
+### Semantics
+
+The `Store` and the `connect` function try to be smart and to optimize as much
+as possible the rendering and update process.  What is important to know is:
+
+- components are always updated in the order of their creation (so, parent
+  before children)
+- they are updated only if they are in the DOM
+- if a parent is asynchronous, the system will wait for it to complete its
+  update before updating other components.
+- in general, updates are not coordinated.  This is not a problem for synchronous
+  components, but if there are many asynchronous components, this could lead to
+  a situation where some part of the UI is updated and other parts of the UI is
+  not updated.
+
+### Good Practices
+
+- avoid asynchronous components as much as possible.  Asynchronous components
+  lead to situations where parts of the UI is not updated immediately.
+- do not be afraid to connect many components, parent or children if needed. For
+  example, a `MessageList` component could get a list of ids in its `mapStoreToProps` and a `Message` component could get the data of its own
+  message
+- since the `mapStoreToProps` function is called for each connected component,
+  for each state update, it is important to make sure that these functions are
+  as fast as possible.

doc/tooling.md

@@ -0,0 +1,55 @@
+# 🦉 Tooling 🦉
+
+## Content
+
+- [Overview](#overview)
+- [Development Mode](#development-mode)
+- [Playground](#playground)
+- [Benchmarks](#benchmarks)
+
+## Overview
+
+To help work with/improve/learn OWL, there are a few extras tools/settings.
+
+- development mode: enable better error reporting for the developer
+- a playground application: a space to experiment and learn Owl.
+- a benchmarks application: allow comparison with a few common frameworks
+
+The two applications are available in the `tools/` folder, and can be accessed
+by using a static http server. A simple python
+server is available in `server.py`. There is also a npm script to start it:
+`npm run tools` (and its version with a watcher: `npm run tools:watch`).
+
+## Development Mode
+
+By default, Owl is in _production_ mode, this means that it will try to do its
+job fast, and skip some expensive operations. However, in some cases, it is
+convenient to have better information on what is going on, this is the purpose
+of the dev mode.
+
+Owl has a mode flag, in `owl.__info__.mode`. Its default value is `prod`, but
+it can be set to `dev`:
+
+```js
+owl.__info__.mode = "dev";
+```
+
+Note that templates compiled with the `prod` settings will not be recompiled.
+So, changing this setting is best done at startup.
+
+## Playground
+
+The playground is an important application designed to help learning and
+experimenting with Owl. The last published version of Owl can be tested [online](https://odoo.github.io/owl/playground/).
+
+It is an application similar to `jsFiddle`, but specialized for Owl: there are
+three tabs (`js`, `css` and `xml`), and a simple button `Run` to execute that
+code in an iframe.
+
+## Benchmarks
+
+Note: This is more an internal tool, useful for people working on Owl.
+
+The benchmarks application is a very small application, implemented in different
+frameworks, and in different versions of Owl. This is a simple internal tool,
+useful to compare various performance metrics on some tasks.

doc/utils.md

@@ -0,0 +1,65 @@
+# 🦉 Utils 🦉
+
+Owl export a few useful utility functions, to help with common issues. Those
+functions are all available in the `owl.utils` namespace.
+
+## Content
+
+- [`whenReady`](#whenready): executing code when DOM is ready
+- [`loadJS`](#loadjs): loading script files
+- [`loadTemplates`](#loadtemplates): loading xml files
+- [`escape`](#escape): sanitizing strings
+- [`debounce`](#debounce): limiting rate of function calls
+
+## `whenReady`
+
+The function `whenReady` returns a `Promise` resolved when the DOM is ready (if
+not ready yet, resolved directly otherwise). If called with a callback as
+argument, it executes it as soon as the DOM ready (or directly).
+
+```js
+Promise.all([loadTemplates(), owl.utils.whenReady()]).then(function([
+  templates
+]) {
+  const qweb = new owl.QWeb(templates);
+  const app = new App({ qweb });
+  app.mount(document.body);
+});
+```
+
+```js
+owl.utils.whenReady(function() {
+  const qweb = new owl.QWeb();
+  const app = new App({ qweb });
+  app.mount(document.body);
+});
+```
+
+## `loadJS`
+
+`loadJS` takes a url (string) for a javascript resource, and loads it. It returns
+a promise, so the caller can properly react when it is ready. Also, it is smart:
+it maintains a list of urls previously loaded (or currently being loaded), and
+prevent doing twice the work.
+
+```js
+class MyComponent extends owl.Component {
+  willStart() {
+    return owl.utils.loadJS("/static/libs/someLib.js");
+  }
+}
+```
+
+## `loadTemplates`
+
+```js
+async function makeEnv() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const qweb = new owl.QWeb(templates);
+  return { qweb };
+}
+```
+
+## `escape`
+
+## `debounce`

doc/vdom.md

@@ -1,3 +1,18 @@
 # 🦉 VDom 🦉
 
-Owl's virtual dom is a fork of [snabbdom](https://github.com/snabbdom/snabbdom).
+Owl is a declarative component system: we declare the structure of the component
+tree, and Owl will translate that to a list of imperative operations. This
+translation is done by a virtual dom. This is the low level layer of Owl, most
+developer will not need to call directly the virtual dom functions.
+
+The main idea behind a virtual dom is to keep a in-memory representation of the
+DOM (called a virtual node), and whenever some change is needed, to regenerate
+a new representation, compute the difference between the old and the new, then
+apply the changes.
+
+`vdom` exports two functions:
+
+- `h`: create a new virtual node
+- `patch`: compare two virtual nodes, and apply the difference.
+
+Note: Owl's virtual dom is a fork of [snabbdom](https://github.com/snabbdom/snabbdom).

extras/benchmarks/odoo-widgets-12.0/templates.xml

@@ -1,30 +0,0 @@
-<templates>
-    <div class="main" t-name="root">
-        <div class="left-thing">
-            <div class="message_count">
-                Number of msg: 0
-            </div>
-            <button class="o_btn_msg 100">Add 100 messages</button>
-            <button class="o_btn_msg 1000">Add 1000 messages</button>
-            <button class="o_btn_msg 10000">Add 10000 messages</button>
-            <button class="o_btn_msg 50000">Add 50000 messages</button>
-            <button class="updateSomeMessages">Update every 10th message</button>
-            <button class="clear">Clear</button>
-        </div>
-        <div class="right-thing">
-            <div class="content">
-            </div>
-        </div>
-    </div>
-
-    <div t-name="message" class="message">
-        <span class="author"><t t-esc="widget.author"/></span>
-        <span class="msg"><t t-esc="widget.msg"/></span>
-        <button class="remove" >Remove</button>
-    </div>
-
-  <div t-name="counter">
-    <button class="o_increment"></button>
-  </div>
-
-</templates>

extras/benchmarks/odoo-widgets-12.3/templates.xml

@@ -1,30 +0,0 @@
-<templates>
-    <div class="main" t-name="root">
-        <div class="left-thing">
-            <div class="message_count">
-                Number of msg: 0
-            </div>
-            <button class="o_btn_msg 100">Add 100 messages</button>
-            <button class="o_btn_msg 1000">Add 1000 messages</button>
-            <button class="o_btn_msg 10000">Add 10000 messages</button>
-            <button class="o_btn_msg 50000">Add 50000 messages</button>
-            <button class="updateSomeMessages">Update every 10th message</button>
-            <button class="clear">Clear</button>
-        </div>
-        <div class="right-thing">
-            <div class="content">
-            </div>
-        </div>
-    </div>
-
-    <div t-name="message" class="message">
-        <span class="author"><t t-esc="widget.author"/></span>
-        <span class="msg"><t t-esc="widget.msg"/></span>
-        <button class="remove" >Remove</button>
-    </div>
-
-  <div t-name="counter">
-    <button class="o_increment"></button>
-  </div>
-
-</templates>

extras/benchmarks/owl-0.7.0/app.js

@@ -1,85 +0,0 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
-
-//------------------------------------------------------------------------------
-// Likes Counter Widget
-//------------------------------------------------------------------------------
-class Counter extends owl.Component {
-  template = "counter";
-  state = { counter: 0 };
-
-  increment() {
-    this.state.counter++;
-  }
-}
-
-//------------------------------------------------------------------------------
-// Message Widget
-//------------------------------------------------------------------------------
-class Message extends owl.Component {
-  template = "message";
-  widgets = { Counter };
-
-  shouldUpdate(nextProps) {
-    return nextProps !== this.props;
-  }
-
-  removeMessage() {
-    this.trigger("remove_message", {
-      id: this.props.id
-    });
-  }
-}
-
-//------------------------------------------------------------------------------
-// Root Widget
-//------------------------------------------------------------------------------
-class App extends owl.Component {
-  template = "root";
-  widgets = { Message };
-  state = { messages: [] };
-
-  addMessages(n) {
-    startMeasure("add " + n);
-    const newMessages = buildData(n);
-    this.state.messages.push.apply(this.state.messages, newMessages);
-    stopMeasure();
-  }
-
-  clear() {
-    startMeasure("clear");
-    this.state.messages = [];
-    stopMeasure();
-  }
-
-  updateSomeMessages() {
-    startMeasure("update every 10th");
-    const messages = this.state.messages;
-    for (let i = 0; i < this.state.messages.length; i += 10) {
-      const msg = Object.assign({}, messages[i]);
-      msg.author += '!!!';
-      this.set(messages, i, msg);
-    }
-    stopMeasure();
-  }
-
-  removeMessage(data) {
-    startMeasure('remove message');
-    const index = this.state.messages.findIndex(m => m.id === data.id);
-    this.state.messages.splice(index, 1);
-    stopMeasure();
-  }
-}
-
-//------------------------------------------------------------------------------
-// Application initialization
-//------------------------------------------------------------------------------
-async function start() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
-  const env = {
-    qweb: new owl.QWeb(templates)
-  };
-  const app = new App(env);
-  app.mount(document.body);
-}
-
-start();

extras/benchmarks/owl-0.7.0/templates.xml

@@ -1,32 +0,0 @@
-<templates>
-  <div t-name="root" class="main">
-      <div class="left-thing">
-          <div>Number of msg: <t t-esc="state.messages.length"/></div>
-          <button t-on-click="addMessages(100)">Add 100 messages</button>
-          <button t-on-click="addMessages(1000)">Add 1000 messages</button>
-          <button t-on-click="addMessages(10000)">Add 10000 messages</button>
-          <button t-on-click="addMessages(50000)">Add 50000 messages</button>
-          <button t-on-click="updateSomeMessages">Update every 10th message</button>
-          <button t-on-click="clear">Clear</button>
-      </div>
-      <div class="right-thing">
-          <div class="content">
-              <t t-foreach="state.messages" t-as="message">
-                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
-              </t>
-          </div>
-      </div>
-  </div>
-
-  <div t-name="message" class="message">
-    <span class="author"><t t-esc="props.author"/></span>
-    <span class="msg"><t t-esc="props.msg"/></span>
-    <button class="remove" t-on-click="removeMessage">Remove</button>
-    <t t-widget="Counter"/>
-  </div>
-
-  <div t-name="counter">
-    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
-  </div>
-
-</templates>

extras/benchmarks/owl-0.8.0/app.js

@@ -1,84 +0,0 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
-
-//------------------------------------------------------------------------------
-// Likes Counter Widget
-//------------------------------------------------------------------------------
-class Counter extends owl.Component {
-  template = "counter";
-  state = { counter: 0 };
-
-  increment() {
-    this.state.counter++;
-  }
-}
-
-//------------------------------------------------------------------------------
-// Message Widget
-//------------------------------------------------------------------------------
-class Message extends owl.Component {
-  template = "message";
-  widgets = { Counter };
-
-  shouldUpdate(nextProps) {
-    return nextProps !== this.props;
-  }
-  removeMessage() {
-    this.trigger("remove_message", {
-      id: this.props.id
-    });
-  }
-}
-
-//------------------------------------------------------------------------------
-// Root Widget
-//------------------------------------------------------------------------------
-class App extends owl.Component {
-  template = "root";
-  widgets = { Message };
-  state = { messages: [] };
-
-  addMessages(n) {
-    startMeasure("add " + n);
-    const newMessages = buildData(n);
-    this.state.messages.push.apply(this.state.messages, newMessages);
-    stopMeasure();
-  }
-
-  clear() {
-    startMeasure("clear");
-    this.state.messages = [];
-    stopMeasure();
-  }
-
-  updateSomeMessages() {
-    startMeasure("update every 10th");
-    const messages = this.state.messages;
-    for (let i = 0; i < this.state.messages.length; i += 10) {
-      const msg = Object.assign({}, messages[i]);
-      msg.author += '!!!';
-      this.set(messages, i, msg);
-    }
-    stopMeasure();
-  }
-
-  removeMessage(data) {
-    startMeasure("remove message");
-    const index = this.state.messages.findIndex(m => m.id === data.id);
-    this.state.messages.splice(index, 1);
-    stopMeasure();
-  }
-}
-
-//------------------------------------------------------------------------------
-// Application initialization
-//------------------------------------------------------------------------------
-async function start() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
-  const env = {
-    qweb: new owl.QWeb(templates)
-  };
-  const app = new App(env);
-  app.mount(document.body);
-}
-
-start();

extras/benchmarks/owl-0.8.0/templates.xml

@@ -1,32 +0,0 @@
-<templates>
-  <div t-name="root" class="main">
-      <div class="left-thing">
-          <div>Number of msg: <t t-esc="state.messages.length"/></div>
-          <button t-on-click="addMessages(100)">Add 100 messages</button>
-          <button t-on-click="addMessages(1000)">Add 1000 messages</button>
-          <button t-on-click="addMessages(10000)">Add 10000 messages</button>
-          <button t-on-click="addMessages(50000)">Add 50000 messages</button>
-          <button t-on-click="updateSomeMessages">Update every 10th message</button>
-          <button t-on-click="clear">Clear</button>
-      </div>
-      <div class="right-thing">
-          <div class="content">
-              <t t-foreach="state.messages" t-as="message">
-                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
-              </t>
-          </div>
-      </div>
-  </div>
-
-  <div t-name="message" class="message">
-    <span class="author"><t t-esc="props.author"/></span>
-    <span class="msg"><t t-esc="props.msg"/></span>
-    <button class="remove" t-on-click="removeMessage">Remove</button>
-    <t t-widget="Counter"/>
-  </div>
-
-  <div t-name="counter">
-    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
-  </div>
-
-</templates>

extras/benchmarks/owl-master/app.js

@@ -1,84 +0,0 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
-
-//------------------------------------------------------------------------------
-// Likes Counter Widget
-//------------------------------------------------------------------------------
-class Counter extends owl.Component {
-  template = "counter";
-  state = { counter: 0 };
-
-  increment() {
-    this.state.counter++;
-  }
-}
-
-//------------------------------------------------------------------------------
-// Message Widget
-//------------------------------------------------------------------------------
-class Message extends owl.Component {
-  template = "message";
-  widgets = { Counter };
-
-  shouldUpdate(nextProps) {
-    return nextProps !== this.props;
-  }
-  removeMessage() {
-    this.trigger("remove_message", {
-      id: this.props.id
-    });
-  }
-}
-
-//------------------------------------------------------------------------------
-// Root Widget
-//------------------------------------------------------------------------------
-class App extends owl.Component {
-  template = "root";
-  widgets = { Message };
-  state = { messages: [] };
-
-  addMessages(n) {
-    startMeasure("add " + n);
-    const newMessages = buildData(n);
-    this.state.messages.push.apply(this.state.messages, newMessages);
-    stopMeasure();
-  }
-
-  clear() {
-    startMeasure("clear");
-    this.state.messages = [];
-    stopMeasure();
-  }
-
-  updateSomeMessages() {
-    startMeasure("update every 10th");
-    const messages = this.state.messages;
-    for (let i = 0; i < this.state.messages.length; i += 10) {
-      const msg = Object.assign({}, messages[i]);
-      msg.author += '!!!';
-      this.set(messages, i, msg);
-    }
-    stopMeasure();
-  }
-
-  removeMessage(data) {
-    startMeasure("remove message");
-    const index = this.state.messages.findIndex(m => m.id === data.id);
-    this.state.messages.splice(index, 1);
-    stopMeasure();
-  }
-}
-
-//------------------------------------------------------------------------------
-// Application initialization
-//------------------------------------------------------------------------------
-async function start() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
-  const env = {
-    qweb: new owl.QWeb(templates)
-  };
-  const app = new App(env);
-  app.mount(document.body);
-}
-
-start();

extras/benchmarks/owl-master/templates.xml

@@ -1,32 +0,0 @@
-<templates>
-  <div t-name="root" class="main">
-      <div class="left-thing">
-          <div>Number of msg: <t t-esc="state.messages.length"/></div>
-          <button t-on-click="addMessages(100)">Add 100 messages</button>
-          <button t-on-click="addMessages(1000)">Add 1000 messages</button>
-          <button t-on-click="addMessages(10000)">Add 10000 messages</button>
-          <button t-on-click="addMessages(50000)">Add 50000 messages</button>
-          <button t-on-click="updateSomeMessages">Update every 10th message</button>
-          <button t-on-click="clear">Clear</button>
-      </div>
-      <div class="right-thing">
-          <div class="content">
-              <t t-foreach="state.messages" t-as="message">
-                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
-              </t>
-          </div>
-      </div>
-  </div>
-
-  <div t-name="message" class="message">
-    <span class="author"><t t-esc="props.author"/></span>
-    <span class="msg"><t t-esc="props.msg"/></span>
-    <button class="remove" t-on-click="removeMessage">Remove</button>
-    <t t-widget="Counter"/>
-  </div>
-
-  <div t-name="counter">
-    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
-  </div>
-
-</templates>

extras/benchmarks/react/app.js

@@ -1,221 +0,0 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
-
-//------------------------------------------------------------------------------
-// Counter Widget
-//------------------------------------------------------------------------------
-class Counter extends React.Component {
-  constructor(props) {
-    super(props);
-    this.state = {
-      counter: 0
-    };
-    this.increment = this.increment.bind(this);
-  }
-
-  render() {
-    return React.createElement(
-      "div",
-      null,
-      React.createElement(
-        "button",
-        {
-          onClick: this.increment
-        },
-        "Value: ",
-        this.state.counter
-      )
-    );
-  }
-
-  increment() {
-    this.setState({
-      counter: this.state.counter + 1
-    });
-  }
-}
-//------------------------------------------------------------------------------
-// Message Widget
-//------------------------------------------------------------------------------
-class Message extends React.Component {
-  constructor(props) {
-    super(props);
-    this.removeMessage = this.removeMessage.bind(this);
-  }
-
-  render() {
-    return React.createElement(
-      "div",
-      {
-        className: "message"
-      },
-      React.createElement(
-        "span",
-        {
-          className: "author"
-        },
-        this.props.message.author
-      ),
-      React.createElement(
-        "span",
-        {
-          className: "msg"
-        },
-        this.props.message.msg
-      ),
-      React.createElement(
-        "button",
-        {
-          className: "remove",
-          onClick: this.removeMessage
-        },
-        "Remove"
-      ),
-      React.createElement(Counter, null)
-    );
-  }
-
-  removeMessage() {
-    this.props.removeCB(this.props.message.id);
-  }
-}
-
-//------------------------------------------------------------------------------
-// Root Widget
-//------------------------------------------------------------------------------
-class Main extends React.Component {
-  constructor(props) {
-    super(props);
-    this.state = {
-      messages: []
-    };
-    this.removeMessage = this.removeMessage.bind(this);
-  }
-
-  render() {
-    const msgList = this.state.messages.map(m =>
-      React.createElement(Message, {
-        key: m.id,
-        message: m,
-        removeCB: this.removeMessage
-      })
-    );
-    return React.createElement(
-      "div",
-      {
-        className: "main"
-      },
-      React.createElement(
-        "div",
-        {
-          className: "left-thing"
-        },
-        React.createElement(
-          "div",
-          null,
-          "Number of msg: ",
-          this.state.messages.length
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.addMessages(100)
-          },
-          "Add 100 messages"
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.addMessages(1000)
-          },
-          "Add 1000 messages"
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.addMessages(10000)
-          },
-          "Add 10000 messages"
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.addMessages(50000)
-          },
-          "Add 50000 messages"
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.updateSomeMessages()
-          },
-          "Update every 10th messags"
-        ),
-        React.createElement(
-          "button",
-          {
-            onClick: _ => this.clear()
-          },
-          "Clear"
-        )
-      ),
-      React.createElement(
-        "div",
-        {
-          className: "right-thing"
-        },
-        React.createElement(
-          "div",
-          {
-            className: "content"
-          },
-          msgList
-        )
-      )
-    );
-  }
-
-  addMessages(n) {
-    startMeasure("add " + n);
-    const newMessages = this.state.messages.concat(buildData(n));
-    this.setState({
-      messages: newMessages
-    });
-    stopMeasure();
-  }
-
-  clear() {
-    startMeasure("clear");
-    this.setState({
-      messages: []
-    });
-    stopMeasure();
-  }
-
-  updateSomeMessages() {
-    startMeasure("update every 10th");
-    const messages = this.state.messages;
-    for (let i = 0; i < messages.length; i += 10) {
-      messages[i].author += "!!!";
-    }
-    this.forceUpdate();
-    stopMeasure();
-  }
-
-  removeMessage(id) {
-    startMeasure("remove message");
-    const index = this.state.messages.findIndex(m => m.id === id);
-    const messages = this.state.messages.slice();
-    messages.splice(index, 1);
-    this.setState({
-      messages
-    });
-    stopMeasure();
-  }
-} //-----------------------------
-// INIT
-//-----------------------------
-
-ReactDOM.render(
-  React.createElement(Main, null),
-  document.getElementById("main")
-);

extras/benchmarks/shared/main.css

@@ -1,42 +0,0 @@
-.main {
-  position: absolute;
-  left: 0;
-  right: 0;
-  top: 0;
-  bottom: 0;
-
-  display: grid;
-  grid-template-columns: 220px 1fr;
-}
-
-.left-thing {
-  background-color: gray;
-  padding: 20px;
-  color: white;
-}
-
-.left-thing button {
-  width: 100%;
-}
-
-.right-thing {
-  padding: 20px;
-  overflow: auto;
-}
-
-/* Message widget */
-.message .author {
-  font-weight: bold;
-}
-
-.message {
-  width: 400px;
-  background-color: lightblue;
-  margin: 10px 5px;
-  border-radius: 5px;
-  padding: 5px;
-}
-
-.remove {
-  float: right;
-}

extras/benchmarks/vue/app.js

@@ -1,106 +0,0 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
-
-//------------------------------------------------------------------------------
-// Counter Widget
-//------------------------------------------------------------------------------
-Vue.component("likes-counter", {
-  data: function() {
-    return {
-      counter: 0
-    };
-  },
-  methods: {
-    increment() {
-      this.counter++;
-    }
-  },
-  template: `
-    <div>
-      <button @click="increment">Value: {{counter}}</button>
-    </div>`
-});
-
-//------------------------------------------------------------------------------
-// Message Widget
-//------------------------------------------------------------------------------
-Vue.component("my-message", {
-  props: ["msg"],
-  methods: {
-    removeMessage() {
-      this.$emit("removeMessage", this.msg.id);
-    }
-  },
-  template: `
-    <div class="message">
-        <span class="author">{{msg.author}}</span>
-        <span class="msg">{{msg.msg}}</span>
-        <button class="remove" @click="removeMessage">Remove</button>
-        <likes-counter></likes-counter>
-    </div>`
-});
-
-//------------------------------------------------------------------------------
-// Root Widget
-//------------------------------------------------------------------------------
-const App = {
-  name: "App",
-  data() {
-    return { messages: [] };
-  },
-  methods: {
-    addMessages(n) {
-      startMeasure("add " + n);
-      const newMessages = buildData(n);
-      this.messages.push.apply(this.messages, newMessages);
-      stopMeasure();
-    },
-
-    clear() {
-      startMeasure("clear");
-      this.messages = [];
-      stopMeasure();
-    },
-
-    updateSomeMessages() {
-      startMeasure("update every 10th");
-      const messages = this.messages;
-      for (let i = 0; i < this.messages.length; i += 10) {
-        messages[i].author += "!!!";
-      }
-      stopMeasure();
-    },
-
-    removeMessage(id) {
-      startMeasure("remove message");
-      const index = this.messages.findIndex(m => m.id === id);
-      this.messages.splice(index, 1);
-      stopMeasure();
-    }
-  },
-  template: `
-    <div class="main">
-        <div class="left-thing">
-            <div>Number of msg: {{messages.length}}</div>
-            <button @click="addMessages(100)">Add 100 messages</button>
-            <button @click="addMessages(1000)">Add 1000 messages</button>
-            <button @click="addMessages(10000)">Add 10000 messages</button>
-            <button @click="addMessages(50000)">Add 50000 messages</button>
-            <button @click="updateSomeMessages">Update every 10th message</button>
-            <button @click="clear">Clear</button>
-        </div>
-        <div class="right-thing">
-            <div class="content">
-                <my-message v-for="msg in messages" v-bind:key="msg.id" v-bind:msg="msg" @removeMessage="removeMessage"></my-message>
-            </div>
-        </div>
-    </div>
-  `
-};
-
-//------------------------------------------------------------------------------
-// Application initialization
-//------------------------------------------------------------------------------
-
-new Vue({
-  render: h => h(App)
-}).$mount(`#main`);

extras/index.html

@@ -1,27 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-  <meta charset="UTF-8">
-  <title>OWL Extras</title>
-</head>
-<body>
-  <h1>🦉 OWL Extra Stuff 🦉</h1>
-
-
-  <h2>Benchmarks</h2>
-  <p>The goal is to compare some operations on large lists</p>
-
-  <ul>
-    <li><a href="benchmarks/odoo-widgets-12.0">Odoo Widgets (12.0)</a></li>
-    <li><a href="benchmarks/odoo-widgets-12.3">Odoo Widgets (12.3)</a></li>
-    <li><a href="benchmarks/owl-0.7.0">OWL 0.7.0</a></li>
-    <li><a href="benchmarks/owl-0.8.0">OWL 0.8.0</a></li>
-    <li><a href="benchmarks/owl-master">OWL Master</a></li>
-    <li><a href="benchmarks/vue">Vue</a></li>
-    <li><a href="benchmarks/react">React</a></li>
-  </ul>
-
-  <h2>Playground</h2>
-  <a href="playground">Playground</a>
-</body>
-</html>

extras/playground/app.js

@@ -1,325 +0,0 @@
-import { SAMPLES } from "./samples.js";
-
-let owlJS;
-
-async function owlSourceCode() {
-  if (owlJS) {
-    return owlJS;
-  }
-  const result = await fetch("../owl.js");
-  owlJS = await result.text();
-  return owlJS;
-}
-
-const MODES = {
-  js: "ace/mode/javascript",
-  css: "ace/mode/css",
-  xml: "ace/mode/xml"
-};
-
-const DEFAULT_XML = `<templates>
-</templates>`;
-
-const DEFAULT_HTML = `<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="utf-8">
-    <title>OWL App</title>
-    <link rel="icon" href="data:,">
-
-    <script src="owl.js"></script>
-    <link rel="stylesheet" href="app.css">
-    <script src="app.js"></script>
-  </head>
-  <body>
-  </body>
-</html>
-`;
-
-const APP_PY = `import sys
-import thread
-import webbrowser
-import time
-
-import BaseHTTPServer, SimpleHTTPServer
-
-def start_server():
-    httpd = BaseHTTPServer.HTTPServer(('127.0.0.1', 3600), SimpleHTTPServer.SimpleHTTPRequestHandler)
-    httpd.serve_forever()
-
-thread.start_new_thread(start_server,())
-url = 'http://127.0.0.1:3600'
-webbrowser.open_new(url)
-
-while True:
-    try:
-        time.sleep(1)
-    except KeyboardInterrupt:
-        sys.exit(0)
-`;
-
-//------------------------------------------------------------------------------
-// Tabbed editor
-//------------------------------------------------------------------------------
-class TabbedEditor extends owl.Component {
-  constructor() {
-    super(...arguments);
-    this.template = "tabbed-editor";
-    this.state = {
-      currentTab: this.props.display.split("|")[0]
-    };
-    this.tabs = {
-      js: this.props.display.includes("js"),
-      xml: this.props.display.includes("xml"),
-      css: this.props.display.includes("css")
-    };
-  }
-
-  mounted() {
-    this.editor = ace.edit(this.refs.editor);
-
-    // remove this for xml/css (?)
-    this.editor.session.setOption("useWorker", false);
-    this.editor.setValue(this.props[this.state.currentTab], -1);
-    this.editor.setFontSize("13px");
-    this.editor.setTheme("ace/theme/monokai");
-    this.editor.session.setMode(MODES[this.state.currentTab]);
-    const tabSize = this.state.currentTab === "xml" ? 2 : 4;
-    this.editor.session.setOption("tabSize", tabSize);
-    this.editor.on("blur", () => {
-      const editorValue = this.editor.getValue();
-      const propsValue = this.props[this.state.currentTab];
-      if (editorValue !== propsValue) {
-        this.trigger("updateCode", {
-          type: this.state.currentTab,
-          value: editorValue
-        });
-      }
-    });
-  }
-
-  patched() {
-    if (this.editor) {
-      window.dispatchEvent(new Event("resize"));
-      this.editor.setValue(this.props[this.state.currentTab], -1);
-    }
-  }
-
-  willUnmount() {
-    this.editor.destroy();
-    delete this.editor;
-  }
-
-  setTab(tab) {
-    this.editor.setValue(this.props[tab], -1);
-
-    const mode = MODES[tab];
-    this.editor.session.setMode(mode);
-    const tabSize = tab === "xml" ? 2 : 4;
-    this.editor.session.setOption("tabSize", tabSize);
-    this.state.currentTab = tab;
-  }
-
-  onMouseDown(ev) {
-    if (ev.target.tagName === "DIV") {
-      let y = ev.clientY;
-      const resizer = ev => {
-        const delta = ev.clientY - y;
-        y = ev.clientY;
-        this.trigger("updatePanelHeight", { delta });
-      };
-      document.body.addEventListener("mousemove", resizer);
-      document.body.addEventListener("mouseup", () => {
-        document.body.removeEventListener("mousemove", resizer);
-      });
-    }
-  }
-}
-
-//------------------------------------------------------------------------------
-// MAIN APP
-//------------------------------------------------------------------------------
-class App extends owl.Component {
-  constructor(...args) {
-    super(...args);
-    this.template = "playground";
-    this.version = owl._version;
-    this.SAMPLES = SAMPLES;
-    this.widgets = { TabbedEditor };
-
-    this.state = {
-      js: SAMPLES[0].code,
-      css: SAMPLES[0].css || "",
-      xml: SAMPLES[0].xml || DEFAULT_XML,
-      error: false,
-      displayWelcome: true,
-      splitLayout: true,
-      leftPaneWidth: Math.ceil(window.innerWidth / 2),
-      topPanelHeight: null
-    };
-  }
-
-  displayError(error) {
-    this.state.error = error;
-    if (error) {
-      setTimeout(() => {
-        this.refs.content.innerHTML = "";
-      });
-      return;
-    }
-  }
-
-  async runCode() {
-    this.state.displayWelcome = false;
-    // check templates
-    var qweb = new owl.QWeb();
-    var error = false;
-    const sanitizedXML = this.state.xml.replace(/<!--[\s\S]*?-->/g, "");
-    try {
-      qweb.loadTemplates(sanitizedXML);
-    } catch (e) {
-      error = e;
-    }
-
-    if (error) {
-      this.displayError(error.message);
-      return;
-    } else {
-      this.state.error = false;
-    }
-
-    // create iframe
-    const iframe = document.createElement("iframe");
-
-    iframe.onload = () => {
-      const doc = iframe.contentDocument;
-      // inject js
-      const owlScript = doc.createElement("script");
-      owlScript.type = "text/javascript";
-      owlScript.src = "../owl.js";
-      owlScript.addEventListener("load", () => {
-        const script = doc.createElement("script");
-        script.type = "text/javascript";
-        const content = `window.TEMPLATES = \`${sanitizedXML}\`\n${
-          this.state.js
-        }`;
-        script.innerHTML = content;
-        const errorHandler = e => this.displayError(e.message);
-        iframe.contentWindow.addEventListener("error", errorHandler);
-        setTimeout(function() {
-          if (iframe.contentWindow) {
-            iframe.contentWindow.removeEventListener("error", errorHandler);
-          }
-        }, 100);
-        doc.body.appendChild(script);
-      });
-      doc.head.appendChild(owlScript);
-
-      // inject css
-      const style = document.createElement("style");
-      style.innerHTML = this.state.css;
-      doc.head.appendChild(style);
-    };
-    this.refs.content.innerHTML = "";
-    this.refs.content.appendChild(iframe);
-  }
-
-  setSample(ev) {
-    const sample = SAMPLES.find(s => s.description === ev.target.value);
-    this.state.js = sample.code;
-    this.state.css = sample.css || "";
-    this.state.xml = sample.xml || DEFAULT_XML;
-  }
-
-  get leftPaneStyle() {
-    return `width:${this.state.leftPaneWidth}px`;
-  }
-
-  get rightPaneStyle() {
-    return `width:${window.innerWidth - 6 - this.state.leftPaneWidth}px`;
-  }
-
-  get topEditorStyle() {
-    return `flex: 0 0 ${this.state.topPanelHeight}px`;
-  }
-
-  onMouseDown() {
-    const resizer = ev => {
-      this.state.leftPaneWidth = ev.clientX;
-    };
-
-    document.body.addEventListener("mousemove", resizer);
-    for (let iframe of document.getElementsByTagName("iframe")) {
-      iframe.classList.add("disabled");
-    }
-
-    document.body.addEventListener("mouseup", () => {
-      document.body.removeEventListener("mousemove", resizer);
-      for (let iframe of document.getElementsByTagName("iframe")) {
-        iframe.classList.remove("disabled");
-      }
-    });
-  }
-  updateCode(ev) {
-    this.state[ev.type] = ev.value;
-  }
-  toggleLayout() {
-    this.state.splitLayout = !this.state.splitLayout;
-  }
-  updatePanelHeight(ev) {
-    if (!ev.delta) {
-      return;
-    }
-    let height = this.state.topPanelHeight;
-    if (!height) {
-      height = document.getElementsByClassName("tabbed-editor")[0].clientHeight;
-    }
-    this.state.topPanelHeight = height + ev.delta;
-  }
-
-  async downloadCode() {
-    await owl.utils.loadJS("libs/FileSaver.min.js");
-    await owl.utils.loadJS("libs/jszip.min.js");
-
-    const zip = new JSZip();
-
-    const JS = `async function startApp() {
-  // Loading templates
-  let TEMPLATES;
-  try {
-    TEMPLATES = await owl.utils.loadTemplates('app.xml');
-  } catch(e) {
-    document.write(\`This app requires a static server.  If you have python installed, try 'python app.py'\`);
-    return;
-  }
-
-  // Application code
-${this.state.js.split('\n').map(l => l === '' ? '' : '  ' + l).join('\n')}
-}
-
-// wait for DOM ready before starting
-owl.utils.whenReady(startApp);`;
-
-    zip.file("app.js", JS);
-    zip.file("app.css", this.state.css);
-    zip.file("app.py", APP_PY);
-    zip.file("app.xml", this.state.xml);
-    zip.file("index.html", DEFAULT_HTML);
-    zip.file("owl.js", owlSourceCode());
-    zip.generateAsync({ type: "blob" }).then(function(content) {
-      saveAs(content, "app.zip");
-    });
-  }
-}
-
-//------------------------------------------------------------------------------
-// Application initialization
-//------------------------------------------------------------------------------
-document.title = `${document.title} (v${owl._version})`;
-document.addEventListener("DOMContentLoaded", async function() {
-  const templates = await owl.utils.loadTemplates("templates.xml");
-  const qweb = new owl.QWeb(templates);
-  const env = { qweb };
-  const app = new App(env);
-  app.mount(document.body);
-});

extras/readme.md

@@ -1,6 +0,0 @@
-# 🦉 Extra Stuff 🦉
-
-To help work/improve/learn with OWL, we have here:
-
-- a benchmarks application
-- a playground application

extras/server.py

@@ -1,34 +0,0 @@
-import sys
-import thread
-import webbrowser
-import time
-
-import BaseHTTPServer
-import SimpleHTTPServer
-
-HOST = '127.0.0.1'
-PORT = 8000
-
-
-class OWLHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):
-    def do_GET(self):
-        if self.path == '/extras/owl.js':
-            self.path = '/dist/owl.js'
-        return SimpleHTTPServer.SimpleHTTPRequestHandler.do_GET(self)
-
-
-def start_server():
-    httpd = BaseHTTPServer.HTTPServer((HOST, PORT), OWLHandler)
-    httpd.serve_forever()
-
-
-if __name__ == "__main__":
-    thread.start_new_thread(start_server, ())
-    url = 'http://{0}:{1}/extras'.format(HOST, PORT)
-    webbrowser.open_new(url)
-
-    while True:
-        try:
-            time.sleep(1)
-        except KeyboardInterrupt:
-            sys.exit(0)

package.json

@@ -1,20 +1,19 @@
 {
   "name": "owl",
-  "version": "0.9.0",
+  "version": "0.16.0",
   "description": "Odoo Web Library (OWL)",
   "main": "src/index.ts",
   "scripts": {
-    "build:js": "tsc --target esnext --module es6 --outDir dist/owl src/*",
-    "build:js:es5": "tsc --target es5 --module es6 --outDir dist/owl src/*",
+    "build:js": "tsc --target esnext --module es6 --outDir dist/owl",
     "build:bundle": "rollup -c",
     "build": "npm run build:js && npm run build:bundle",
-    "build:es5": "npm run build:js:es5 && npm run build:bundle",
     "minify": "uglifyjs dist/owl.js -o dist/owl.min.js --compress --mangle",
-    "dev": "npm-run-all --parallel \"build:* -- --watch\"",
     "test": "jest",
     "test:watch": "jest --watch",
-    "preextras": "npm run build",
-    "extras": "python extras/server.py"
+    "tools:serve": "python3 tools/server.py || python tools/server.py",
+    "tools": "npm run build && npm run tools:serve",
+    "pretools:watch": "npm run build",
+    "tools:watch": "npm-run-all  --parallel tools:serve \"build:* -- --watch\""
   },
   "repository": {
     "type": "git",
@@ -36,16 +35,13 @@
     "rollup": "^1.6.0",
     "rollup-plugin-typescript2": "^0.20.1",
     "sass": "^1.16.1",
-    "snabbdom-to-html": "^5.1.1",
     "source-map-support": "^0.5.10",
     "ts-jest": "^23.10.5",
     "typescript": "^3.2.2",
-    "uglify-es": "^3.3.9"
-  },
-  "dependencies": {
-    "jest-environment-jsdom": "^24.7.1",
-    "snabbdom": "^0.7.3"
+    "uglify-es": "^3.3.9",
+    "jest-environment-jsdom": "^24.7.1"
   },
+  "dependencies": {},
   "jest": {
     "roots": [
       "<rootDir>/src",
@@ -64,5 +60,8 @@
       "json",
       "node"
     ]
+  },
+  "prettier": {
+      "printWidth": 100
   }
 }

rollup.config.js

@@ -9,6 +9,6 @@ export default {
     format: "iife",
     name: "owl",
     extend: true,
-    outro: `exports._version = '${version}';\nexports._date = '${new Date().toISOString()}';\nexports._hash = '${git.short()}';\nexports._url = 'https://github.com/odoo/owl';`
+    outro: `exports.__info__.version = '${version}';\nexports.__info__.date = '${new Date().toISOString()}';\nexports.__info__.hash = '${git.short()}';\nexports.__info__.url = 'https://github.com/odoo/owl';`
   }
 };

src/component.ts

@@ -1,26 +1,49 @@
-import { EventBus } from "./event_bus";
 import { Observer } from "./observer";
-import { QWeb, CompiledTemplate } from "./qweb";
+import { QWeb, CompiledTemplate } from "./qweb_core";
 import { h, patch, VNode } from "./vdom";
 
+/**
+ * Owl Component System
+ *
+ * This file introduces a declarative and composable component system. It
+ * contains:
+ *
+ * - the Env interface (generic type for the environment)
+ * - the Meta interface (the owl specific metadata attached to a component)
+ * - the Component class
+ */
+
 //------------------------------------------------------------------------------
 // Types/helpers
 //------------------------------------------------------------------------------
 
+/**
+ * An Env (environment) is an object that will be (mostly) shared between all
+ * components of an Owl application.  It is the location which should contain
+ * the qweb instance necessary to render all components.
+ *
+ * Note that it is totally fine to extend the environment with application
+ * specific keys/objects/whatever.  For example, a key `isMobile` (to declare
+ * if we are in "mobile" mode), or a shared bus could be useful.
+ */
 export interface Env {
   qweb: QWeb;
 }
 
-interface Meta<T extends Env, Props> {
+/**
+ * This is mostly an internal detail of implementation. The Meta interface is
+ * useful to typecheck and describe the internal keys used by Owl to manage the
+ * component tree.
+ */
+export interface Meta<T extends Env, Props> {
   readonly id: number;
   vnode: VNode | null;
-  isStarted: boolean;
   isMounted: boolean;
   isDestroyed: boolean;
   parent: Component<T, any, any> | null;
   children: { [key: number]: Component<T, any, any> };
-  // children mapping: from templateID to widgetID
-  // should it be a map number => Widget?
+  // children mapping: from templateID to componentID
+  // should it be a map number => Component?
   cmap: { [key: number]: number };
 
   renderId: number;
@@ -29,22 +52,29 @@ interface Meta<T extends Env, Props> {
   boundHandlers: { [key: number]: any };
   observer?: Observer;
   render?: CompiledTemplate;
+  mountedHandlers: { [key: number]: Function };
+  classObj?: { [key: string]: boolean };
 }
 
+// If a component does not define explicitely a template
+// key, it needs to find a template with its name (or a parent's).  This is
+// qweb dependant, so we need a place to store this information indexed by
+// qweb instances.
+const TEMPLATE_MAP: { [key: number]: { [name: string]: string } } = {};
+
 //------------------------------------------------------------------------------
-// Widget
+// Component
 //------------------------------------------------------------------------------
 let nextId = 1;
 
-export class Component<
-  T extends Env,
-  Props extends {},
-  State extends {}
-> extends EventBus {
+export class Component<T extends Env, Props extends {}, State extends {}> {
   readonly __owl__: Meta<Env, Props>;
-  template: string = "default";
-  inlineTemplate: string | null = null;
+  template?: string;
 
+  /**
+   * The `el` is the root element of the component.  Note that it could be null:
+   * this is the case if the component is not mounted yet, or is destroyed.
+   */
   get el(): HTMLElement | null {
     return this.__owl__.vnode ? (<any>this).__owl__.vnode.elm : null;
   }
@@ -52,6 +82,11 @@ export class Component<
   env: T;
   state?: State;
   props: Props;
+
+  // type of props is not easily representable in typescript...
+  static props?: any;
+  static defaultProps?: any;
+
   refs: {
     [key: string]: Component<T, any, any> | HTMLElement | undefined;
   } = {};
@@ -63,29 +98,34 @@ export class Component<
   /**
    * Creates an instance of Component.
    *
-   * The root widget of a component tree needs an environment:
+   * The root component of a component tree needs an environment:
    *
    * ```javascript
-   *   const root = new RootWidget(env, props);
+   *   const root = new RootComponent(env, props);
    * ```
    *
-   * Every other widget simply needs a reference to its parent:
+   * Every other component simply needs a reference to its parent:
    *
    * ```javascript
-   *   const child = new SomeWidget(parent, props);
+   *   const child = new SomeComponent(parent, props);
    * ```
    *
-   * Note that most of the time, only the root widget needs to be created by
-   * hand.  Other widgets should be created automatically by the framework (with
-   * the t-widget directive in a template)
+   * Note that most of the time, only the root component needs to be created by
+   * hand.  Other components should be created automatically by the framework (with
+   * the t-component directive in a template)
    */
   constructor(parent: Component<T, any, any> | T, props?: Props) {
-    super();
-
+    const defaultProps = (<any>this.constructor).defaultProps;
+    if (defaultProps) {
+      props = this.__applyDefaultProps(props, defaultProps);
+    }
+    if (QWeb.dev) {
+      this.__validateProps(props || {});
+    }
     // is this a good idea?
-    //   Pro: if props is empty, we can create easily a widget
+    //   Pro: if props is empty, we can create easily a component
     //   Con: this is not really safe
-    //   Pro: but creating widget (by a template) is always unsafe anyway
+    //   Pro: but creating component (by a template) is always unsafe anyway
     this.props = <Props>props || <Props>{};
     let id: number = nextId++;
     let p: Component<T, any, any> | null = null;
@@ -95,11 +135,23 @@ export class Component<
       parent.__owl__.children[id] = this;
     } else {
       this.env = parent;
+      this.env.qweb.on("update", this, () => {
+        if (this.__owl__.isMounted) {
+          this.render(true);
+        }
+        if (this.__owl__.isDestroyed) {
+          // this is unlikely to happen, but if a root widget is destroyed,
+          // we want to remove our subscription.  The usual way to do that
+          // would be to perform some check in the destroy method, but since
+          // it is very performance sensitive, and since this is a rare event,
+          // we simply do it lazily
+          this.env.qweb.off("update", this);
+        }
+      });
     }
     this.__owl__ = {
       id: id,
       vnode: null,
-      isStarted: false,
       isMounted: false,
       isDestroyed: false,
       parent: p,
@@ -108,7 +160,8 @@ export class Component<
       renderId: 1,
       renderPromise: null,
       renderProps: props || null,
-      boundHandlers: {}
+      boundHandlers: {},
+      mountedHandlers: {}
     };
   }
 
@@ -118,7 +171,7 @@ export class Component<
    *
    * It will be called exactly once before the initial rendering. It is useful
    * in some cases, for example, to load external assets (such as a JS library)
-   * before the widget is rendered.
+   * before the component is rendered.
    *
    * Note that a slow willStart method will slow down the rendering of the user
    * interface.  Therefore, some effort should be made to make this method as
@@ -168,7 +221,7 @@ export class Component<
    * with the DOM (for example, through an external library) whenever the
    * component was updated.
    *
-   * Updating the widget state in this hook is possible, but not encouraged.
+   * Updating the component state in this hook is possible, but not encouraged.
    * One need to be careful, because updates here will cause rerender, which in
    * turn will cause other calls to updated. So, we need to be particularly
    * careful at avoiding endless cycles.
@@ -192,118 +245,85 @@ export class Component<
   // Public
   //--------------------------------------------------------------------------
 
+  /**
+   * Mount the component to a target element.
+   *
+   * This should only be done if the component was created manually. Components
+   * created declaratively in templates are managed by the Owl system.
+   */
   async mount(target: HTMLElement): Promise<void> {
-    const vnode = await this._prepare();
+    const vnode = await this.__prepare();
     if (this.__owl__.isDestroyed) {
-      // widget was destroyed before we get here...
+      // component was destroyed before we get here...
       return;
     }
-    this._patch(vnode);
+    this.__patch(vnode);
     target.appendChild(this.el!);
 
     if (document.body.contains(target)) {
-      this._callMounted();
-    }
-  }
-
-  _callMounted() {
-    const children = this.__owl__.children;
-    for (let id in children) {
-      const comp = children[id];
-      if (!comp.__owl__.isMounted && this.el!.contains(comp.el)) {
-        comp._callMounted();
-      }
-    }
-    this.__owl__.isMounted = true;
-    this.mounted();
-  }
-
-  _callWillUnmount() {
-    this.willUnmount();
-    this.__owl__.isMounted = false;
-    const children = this.__owl__.children;
-    for (let id in children) {
-      const comp = children[id];
-      if (comp.__owl__.isMounted) {
-        comp._callWillUnmount();
-      }
+      this.__callMounted();
     }
   }
 
   unmount() {
     if (this.__owl__.isMounted) {
-      this._callWillUnmount();
+      this.__callWillUnmount();
       this.el!.remove();
     }
   }
 
   async render(force: boolean = false, patchQueue?: any[]): Promise<void> {
-    if (this.__owl__.isDestroyed) {
+    const __owl__ = this.__owl__;
+    if (!__owl__.isMounted) {
       return;
     }
-    const shouldCallPatchHooks: boolean = !patchQueue;
-    if (shouldCallPatchHooks) {
+    const shouldPatch: boolean = !patchQueue;
+    if (shouldPatch) {
       patchQueue = [];
     }
-    const renderVDom = this._render(force, patchQueue);
-    const renderId = this.__owl__.renderId;
-    const vnode = await renderVDom;
-    if (renderId === this.__owl__.renderId) {
+    const renderVDom = this.__render(force, patchQueue);
+    const renderId = __owl__.renderId;
+    await renderVDom;
+
+    if (shouldPatch && __owl__.isMounted && renderId === __owl__.renderId) {
       // we only update the vnode and the actual DOM if no other rendering
       // occurred between now and when the render method was initially called.
-      if (shouldCallPatchHooks) {
-        for (let i = 0; i < patchQueue!.length; i++) {
-          const c = patchQueue![i];
-          c.__owl__.willPatchVal = c.willPatch();
-        }
-      }
-      this._patch(vnode);
-      if (shouldCallPatchHooks) {
-        for (let i = patchQueue!.length - 1; i >= 0; i--) {
-          const c = patchQueue![i];
-          c.patched(c.__owl__.willPatchVal);
-        }
-      }
+      this.__applyPatchQueue(<any[]>patchQueue);
     }
   }
 
+  /**
+   * Destroy the component.  This operation is quite complex:
+   *  - it recursively destroy all children
+   *  - call the willUnmount hooks if necessary
+   *  - remove the dom node from the dom
+   *
+   * This should only be called manually if you created the component.  Most
+   * components will be automatically destroyed.
+   */
   destroy() {
-    if (!this.__owl__.isDestroyed) {
+    const __owl__ = this.__owl__;
+    if (!__owl__.isDestroyed) {
       const el = this.el;
-      this._destroy(this.__owl__.parent);
+      this.__destroy(__owl__.parent);
       if (el) {
         el.remove();
       }
     }
   }
 
-  _destroy(parent) {
-    const isMounted = this.__owl__.isMounted;
-    if (isMounted) {
-      this.willUnmount();
-      this.__owl__.isMounted = false;
-    }
-    const children = Object.values(this.__owl__.children);
-    for (let child of children) {
-      child._destroy(this);
-    }
-    if (parent) {
-      let id = this.__owl__.id;
-      delete parent.__owl__.children[id];
-      this.__owl__.parent = null;
-    }
-    this.clear();
-    this.__owl__.isDestroyed = true;
-    delete this.__owl__.vnode;
-  }
-
+  /**
+   * This method is called by the component system whenever its props are
+   * updated. If it returns true, then the component will be rendered.
+   * Otherwise, it will skip the rendering (also, its props will not be updated)
+   */
   shouldUpdate(nextProps: Props): boolean {
     return true;
   }
 
   /**
-   * This method is the correct way to update the environment of a widget. Doing
-   * this will cause a full rerender of the widget and its children, so this is
+   * This method is the correct way to update the environment of a component. Doing
+   * this will cause a full rerender of the component and its children, so this is
    * an operation that should not be done frequently.
    *
    * A good usecase for updating the environment would be to update some mostly
@@ -311,126 +331,342 @@ export class Component<
    * mode or not.
    */
   async updateEnv(nextEnv: Partial<T>): Promise<void> {
-    if (this.__owl__.parent && this.__owl__.parent.env === this.env) {
+    const __owl__ = this.__owl__;
+    if (__owl__.parent && __owl__.parent.env === this.env) {
       this.env = Object.create(this.env);
     }
     Object.assign(this.env, nextEnv);
-    if (this.__owl__.isMounted) {
+    if (__owl__.isMounted) {
       await this.render(true);
     }
   }
 
-  set(target: any, key: string | number, value: any) {
-    this.__owl__.observer!.set(target, key, value);
+  /**
+   * Emit a custom event of type 'eventType' with the given 'payload' on the
+   * component's el, if it exists. However, note that the event will only bubble
+   * up to the parent DOM nodes. Thus, it must be called between mounted() and
+   * willUnmount().
+   */
+  trigger(eventType: string, payload?: any) {
+    if (this.el) {
+      const ev = new CustomEvent(eventType, {
+        bubbles: true,
+        cancelable: true,
+        detail: payload
+      });
+      this.el.dispatchEvent(ev);
+    }
   }
 
   //--------------------------------------------------------------------------
   // Private
   //--------------------------------------------------------------------------
 
-  async _updateProps(
+  __destroy(parent: Component<any, any, any> | null) {
+    const __owl__ = this.__owl__;
+    const isMounted = __owl__.isMounted;
+    if (isMounted) {
+      this.willUnmount();
+      __owl__.isMounted = false;
+    }
+    const children = __owl__.children;
+    for (let key in children) {
+      children[key].__destroy(this);
+    }
+    if (parent) {
+      let id = __owl__.id;
+      delete parent.__owl__.children[id];
+      __owl__.parent = null;
+    }
+    __owl__.isDestroyed = true;
+    delete __owl__.vnode;
+  }
+
+  __callMounted() {
+    const __owl__ = this.__owl__;
+    const children = __owl__.children;
+    for (let id in children) {
+      const comp = children[id];
+      if (!comp.__owl__.isMounted && this.el!.contains(comp.el)) {
+        comp.__callMounted();
+      }
+    }
+    __owl__.isMounted = true;
+    const handlers = __owl__.mountedHandlers;
+    for (let key in handlers) {
+      handlers[key]();
+    }
+    this.mounted();
+  }
+
+  __callWillUnmount() {
+    this.willUnmount();
+    const __owl__ = this.__owl__;
+    __owl__.isMounted = false;
+    const children = __owl__.children;
+    for (let id in children) {
+      const comp = children[id];
+      if (comp.__owl__.isMounted) {
+        comp.__callWillUnmount();
+      }
+    }
+  }
+
+  async __updateProps(
     nextProps: Props,
     forceUpdate: boolean = false,
-    patchQueue: any[]
+    patchQueue?: any[]
   ): Promise<void> {
     const shouldUpdate = forceUpdate || this.shouldUpdate(nextProps);
     if (shouldUpdate) {
+      const defaultProps = (<any>this.constructor).defaultProps;
+      if (defaultProps) {
+        nextProps = this.__applyDefaultProps(nextProps, defaultProps);
+      }
+      if (QWeb.dev) {
+        this.__validateProps(nextProps);
+      }
       await this.willUpdateProps(nextProps);
       this.props = nextProps;
-      await this.render(false, patchQueue);
+      await this.render(forceUpdate, patchQueue);
     }
   }
 
-  _patch(vnode) {
-    this.__owl__.renderPromise = null;
-    if (this.__owl__.vnode) {
-      this.__owl__.vnode = patch(this.__owl__.vnode, vnode);
-    } else {
-      this.__owl__.vnode = patch(document.createElement(vnode.sel!), vnode);
+  __patch(vnode) {
+    const __owl__ = this.__owl__;
+    __owl__.renderPromise = null;
+    const target = __owl__.vnode || document.createElement(vnode.sel!);
+    if (this.__owl__.classObj) {
+      (<any>vnode).data.class = Object.assign((<any>vnode).data.class || {}, this.__owl__.classObj);
     }
-  }
-  _prepare(): Promise<VNode> {
-    this.__owl__.renderProps = this.props;
-    this.__owl__.renderPromise = this._prepareAndRender();
-    return this.__owl__.renderPromise;
+    __owl__.vnode = patch(target, vnode);
   }
 
-  async _prepareAndRender(): Promise<VNode> {
+  __prepare(): Promise<VNode> {
+    const __owl__ = this.__owl__;
+    __owl__.renderProps = this.props;
+    __owl__.renderPromise = this.__prepareAndRender();
+    return __owl__.renderPromise;
+  }
+
+  async __prepareAndRender(): Promise<VNode> {
     await this.willStart();
-    if (this.__owl__.isDestroyed) {
+    const __owl__ = this.__owl__;
+    if (__owl__.isDestroyed) {
       return Promise.resolve(h("div"));
     }
-    this.__owl__.isStarted = true;
-    if (this.inlineTemplate) {
-      this.env.qweb.addTemplate(this.inlineTemplate, this.inlineTemplate, true);
+    const qweb = this.env.qweb;
+    if (!this.template) {
+      let tmap = TEMPLATE_MAP[qweb.id];
+      if (!tmap) {
+        tmap = {};
+        TEMPLATE_MAP[qweb.id] = tmap;
+      }
+      let p = (<any>this).constructor;
+      let name: string = p.name;
+      let template = tmap[name];
+      if (template) {
+        this.template = template;
+      } else {
+        while ((template = p.name) && !(template in qweb.templates) && p !== Component) {
+          p = p.__proto__;
+        }
+        if (p === Component) {
+          throw new Error(`Could not find template for component "${this.constructor.name}"`);
+        } else {
+          tmap[name] = template;
+          this.template = template;
+        }
+      }
     }
-    this.__owl__.render = this.env.qweb.render.bind(
-      this.env.qweb,
-      this.inlineTemplate || this.template
-    );
-    this._observeState();
-    return this._render();
+    __owl__.render = qweb.render.bind(qweb, this.template);
+    this.__observeState();
+    return this.__render();
   }
-  async _render(
-    force: boolean = false,
-    patchQueue: any[] = []
-  ): Promise<VNode> {
-    if (this.__owl__.isMounted) {
-      patchQueue.push(this);
-    }
-    this.__owl__.renderId++;
+
+  async __render(force: boolean = false, patchQueue: any[] = []): Promise<VNode> {
+    const __owl__ = this.__owl__;
+    __owl__.renderId++;
     const promises: Promise<void>[] = [];
-    if (this.__owl__.observer) {
-      this.__owl__.observer.allowMutations = false;
+    const patch: any[] = [this];
+    if (__owl__.isMounted) {
+      patchQueue.push(patch);
     }
-    let vnode = this.__owl__.render!(this, {
+    if (__owl__.observer) {
+      __owl__.observer.allowMutations = false;
+    }
+    let vnode = __owl__.render!(this, {
       promises,
-      handlers: this.__owl__.boundHandlers,
+      handlers: __owl__.boundHandlers,
+      mountedHandlers: __owl__.mountedHandlers,
       forceUpdate: force,
       patchQueue
     });
-    if (this.__owl__.observer) {
-      this.__owl__.observer.allowMutations = true;
+    patch.push(vnode);
+    if (__owl__.observer) {
+      __owl__.observer.allowMutations = true;
     }
 
     // this part is critical for the patching process to be done correctly. The
-    // tricky part is that a child widget can be rerendered on its own, which
+    // tricky part is that a child component can be rerendered on its own, which
     // will update its own vnode representation without the knowledge of the
-    // parent widget.  With this, we make sure that the parent widget will be
+    // parent component.  With this, we make sure that the parent component will be
     // able to patch itself properly after
-    vnode.key = this.__owl__.id;
-    this.__owl__.renderProps = this.props;
-    this.__owl__.renderPromise = Promise.all(promises).then(() => vnode);
-    return this.__owl__.renderPromise;
+    vnode.key = __owl__.id;
+    __owl__.renderProps = this.props;
+    __owl__.renderPromise = Promise.all(promises).then(() => vnode);
+    return __owl__.renderPromise;
   }
 
   /**
-   * Only called by qweb t-widget directive
+   * Only called by qweb t-component directive
    */
-  _mount(vnode: VNode, elm: HTMLElement): VNode {
-    this.__owl__.vnode = patch(elm, vnode);
-    if (
-      this.__owl__.parent &&
-      this.__owl__.parent.__owl__.isMounted &&
-      !this.__owl__.isMounted
-    ) {
-      this._callMounted();
+  __mount(vnode: VNode, elm: HTMLElement): VNode {
+    const __owl__ = this.__owl__;
+    if (__owl__.classObj) {
+      (<any>vnode).data.class = Object.assign((<any>vnode).data.class || {}, __owl__.classObj);
     }
-    return this.__owl__.vnode;
+    __owl__.vnode = patch(elm, vnode);
+    if (__owl__.parent!.__owl__.isMounted && !__owl__.isMounted) {
+      this.__callMounted();
+    }
+    return __owl__.vnode;
   }
 
-  __mount() {
-    if (!this.__owl__.isMounted) {
-      this.__owl__.isMounted = true;
+  /**
+   * Only called by qweb t-component directive (when t-keepalive is set)
+   */
+  __remount() {
+    const __owl__ = this.__owl__;
+    if (!__owl__.isMounted) {
+      __owl__.isMounted = true;
       this.mounted();
     }
   }
 
-  _observeState() {
+  __observeState() {
     if (this.state) {
-      this.__owl__.observer = new Observer();
-      this.__owl__.observer.observe(this.state);
-      this.__owl__.observer.notifyCB = this.render.bind(this);
+      const __owl__ = this.__owl__;
+      __owl__.observer = new Observer();
+      __owl__.observer.observe(this.state);
+      __owl__.observer.notifyCB = this.render.bind(this);
+    }
+  }
+
+  /**
+   * Apply default props (only top level).
+   *
+   * Note that this method does not modify in place the props, it returns a new
+   * prop object
+   */
+  __applyDefaultProps(props: Object | undefined, defaultProps: Object): Props {
+    props = props ? Object.create(props) : {};
+    for (let propName in defaultProps) {
+      if (props![propName] === undefined) {
+        props![propName] = defaultProps[propName];
+      }
+    }
+    return <Props>props;
+  }
+
+  /**
+   * Apply the given patch queue. A patch is a pair [c, vn], where c is a
+   * Component instance and vn a VNode.
+   *   1) Call 'willPatch' on the component of each patch
+   *   2) Call '__patch' on the component of each patch
+   *   3) Call 'patched' on the component of each patch, in inverse order
+   */
+  __applyPatchQueue(patchQueue: any[]) {
+    const patchLen = patchQueue.length;
+    for (let i = 0; i < patchLen; i++) {
+      const patch = patchQueue[i];
+      patch.push(patch[0].willPatch());
+    }
+    for (let i = 0; i < patchLen; i++) {
+      const patch = patchQueue[i];
+      patch[0].__patch(patch[1]);
+    }
+    for (let i = patchLen - 1; i >= 0; i--) {
+      const patch = patchQueue[i];
+      patch[0].patched(patch[2]);
+    }
+  }
+
+  /**
+   * Validate the component props (or next props) against the (static) props
+   * description.  This is potentially an expensive operation: it may needs to
+   * visit recursively the props and all the children to check if they are valid.
+   * This is why it is only done in 'dev' mode.
+   */
+  __validateProps(props: Object) {
+    const propsDef = (<any>this.constructor).props;
+    if (propsDef instanceof Array) {
+      // list of strings (prop names)
+      for (let i = 0, l = propsDef.length; i < l; i++) {
+        if (!(propsDef[i] in props)) {
+          throw new Error(`Missing props '${propsDef[i]}' (component '${this.constructor.name}')`);
+        }
+      }
+    } else if (propsDef) {
+      // propsDef is an object now
+      for (let propName in propsDef) {
+        if (!(propName in props)) {
+          if (propsDef[propName] && !propsDef[propName].optional) {
+            throw new Error(`Missing props '${propName}' (component '${this.constructor.name}')`);
+          } else {
+            break;
+          }
+        }
+        let isValid = isValidProp(props[propName], propsDef[propName]);
+        if (!isValid) {
+          throw new Error(
+            `Props '${propName}' of invalid type in component '${this.constructor.name}'`
+          );
+        }
+      }
     }
   }
 }
+
+//------------------------------------------------------------------------------
+// Prop validation helper
+//------------------------------------------------------------------------------
+
+/**
+ * Check if an invidual prop value matches its (static) prop definition
+ */
+function isValidProp(prop, propDef): boolean {
+  if (typeof propDef === "function") {
+    // Check if a value is constructed by some Constructor.  Note that there is a
+    // slight abuse of language: we want to consider primitive values as well.
+    //
+    // So, even though 1 is not an instance of Number, we want to consider that
+    // it is valid.
+    if (typeof prop === "object") {
+      return prop instanceof propDef;
+    }
+    return typeof prop === propDef.name.toLowerCase();
+  } else if (propDef instanceof Array) {
+    // If this code is executed, this means that we want to check if a prop
+    // matches at least one of its descriptor.
+    let result = false;
+    for (let i = 0, iLen = propDef.length; i < iLen; i++) {
+      result = result || isValidProp(prop, propDef[i]);
+    }
+    return result;
+  }
+  // propsDef is an object
+  let result = isValidProp(prop, propDef.type);
+  if (propDef.type === Array) {
+    for (let i = 0, iLen = prop.length; i < iLen; i++) {
+      result = result && isValidProp(prop[i], propDef.element);
+    }
+  }
+  if (propDef.type === Object) {
+    const shape = propDef.shape;
+    for (let key in shape) {
+      result = result && isValidProp(prop[key], shape[key]);
+    }
+  }
+  return result;
+}

src/event_bus.ts

@@ -3,7 +3,8 @@
  * - emit events
  * - add/remove listeners.
  *
- * This is a useful pattern of communication in some cases.
+ * This is a useful pattern of communication in many cases.  For OWL, each
+ * components and stores are event buses.
  */
 
 //------------------------------------------------------------------------------
@@ -28,7 +29,7 @@ export class EventBus {
    * Add a listener for the 'eventType' events.
    *
    * Note that the 'owner' of this event can be anything, but will more likely
-   * be a widget or a class. The idea is that the callback will be called with
+   * be a component or a class. The idea is that the callback will be called with
    * the proper owner bound.
    *
    * Also, the owner should be kind of unique. This will be used to remove the
@@ -63,7 +64,8 @@ export class EventBus {
    */
   trigger(eventType: string, ...args: any[]) {
     const subs = this.subscriptions[eventType] || [];
-    for (let sub of subs) {
+    for (let i = 0, iLen = subs.length; i < iLen; i++) {
+      const sub = subs[i];
       sub.callback.call(sub.owner, ...args);
     }
   }

src/index.ts

@@ -1,8 +1,39 @@
+/**
+ * This file is the main file packaged by rollup (see rollup.config.js).  From
+ * this file, we export all public owl elements.
+ *
+ * Note that dynamic values, such as a date or a commit hash are added by rollup
+ */
 export { Component } from "./component";
 export { EventBus } from "./event_bus";
 export { Observer } from "./observer";
-export { QWeb } from "./qweb";
+
+// we need to import manually the extra directives so they can register
+// themselves in QWeb, otherwise these files will not even be loaded.
+import "./qweb_directives";
+import "./qweb_extensions";
+import { QWeb } from "./qweb_core";
+export { QWeb };
+
 export { connect, Store } from "./store";
 import * as _utils from "./utils";
 
+export const __info__ = {};
+
+Object.defineProperty(__info__, "mode", {
+  get() {
+    return QWeb.dev ? "dev" : "prod";
+  },
+  set(mode: string) {
+    QWeb.dev = mode === "dev";
+    if (QWeb.dev) {
+      const url = `https://github.com/odoo/owl/blob/master/doc/tooling.md#development-mode`;
+      console.warn(
+        `Owl is running in 'dev' mode.  This is not suitable for production use. See ${url} for more information.`
+      );
+    } else {
+      console.log(`Owl is now running in 'prod' mode.`);
+    }
+  }
+});
 export const utils = _utils;

src/observer.ts

@@ -1,26 +1,40 @@
+/**
+ * Owl Observer
+ *
+ * This code contains the logic that allows Owl to observe and react to state
+ * changes.
+ *
+ * This is a Observer class that can observe any JS values.  The way it works
+ * can be summarized thusly:
+ * - primitive values are not observed at all
+ * - Objects are observed by replacing all their keys with getters/setters
+ *   (recursively)
+ * - Arrays are observed by replacing their prototype with a customized version,
+ *   which wrap some methods to allow the tracking of each state change.
+ *
+ * Note that this code is inspired by Vue.
+ */
+
 //------------------------------------------------------------------------------
-// Observer
+// Modified Array prototype
 //------------------------------------------------------------------------------
 
-const methodsToPatch = [
-  "push",
-  "pop",
-  "shift",
-  "unshift",
-  "splice",
-  "sort",
-  "reverse"
-];
+// we define here a new modified Array prototype, which basically override all
+// Array methods that change some state to be able to track their changes
+const methodsToPatch = ["push", "pop", "shift", "unshift", "splice", "sort", "reverse"];
+const methodLen = methodsToPatch.length;
 
 const ArrayProto = Array.prototype;
 const ModifiedArrayProto = Object.create(ArrayProto);
 
-for (let method of methodsToPatch) {
+for (let i = 0; i < methodLen; i++) {
+  const method = methodsToPatch[i];
   const initialMethod = ArrayProto[method];
   ModifiedArrayProto[method] = function(...args) {
     if (!this.__observer__.allowMutations) {
       throw new Error(`Array cannot be changed here")`);
     }
+    this.__observer__.rev++;
     this.__observer__.notifyChange();
     this.__owl__.rev++;
     let parent = this;
@@ -38,22 +52,38 @@ for (let method of methodsToPatch) {
         break;
     }
     if (inserted) {
-      for (let elem of inserted) {
-        this.__observer__.observe(elem, this);
+      for (let i = 0, iLen = inserted.length; i < iLen; i++) {
+        this.__observer__.observe(inserted[i], this);
       }
     }
     return initialMethod.call(this, ...args);
   };
 }
 
+//------------------------------------------------------------------------------
+// Observer
+//------------------------------------------------------------------------------
 export class Observer {
   rev: number = 1;
   allowMutations: boolean = true;
   dirty: boolean = false;
 
+  static set(target: any, key: number | string, value: any) {
+    if (!target.__owl__) {
+      throw Error("`Observer.set()` can only be called with observed Objects or Arrays");
+    }
+    target.__owl__.observer.set(target, key, value);
+  }
+
+  static delete(target: any, key: number | string) {
+    if (!target.__owl__) {
+      throw Error("`Observer.delete()` can only be called with observed Objects");
+    }
+    target.__owl__.observer.delete(target, key);
+  }
+
   notifyCB() {}
   notifyChange() {
-    this.rev++;
     this.dirty = true;
     Promise.resolve().then(() => {
       if (this.dirty) {
@@ -84,37 +114,55 @@ export class Observer {
   }
 
   set(target: any, key: number | string, value: any) {
-    this._addProp(target, key, value);
-    target.__owl__.rev++;
+    let alreadyDefined =
+      key in target && Object.getOwnPropertyDescriptor(target, key)!.configurable === false;
+    if (alreadyDefined) {
+      target[key] = value;
+    } else {
+      this._addProp(target, key, value);
+      this._updateRevNumber(target);
+    }
+    this.notifyChange();
+  }
+
+  delete(target: any, key: number | string) {
+    delete target[key];
+    this._updateRevNumber(target);
     this.notifyChange();
   }
 
   _observeObj<T extends { __owl__?: any }>(obj: T, parent?: any) {
-    const keys = Object.keys(obj);
-    obj.__owl__ = { rev: 1, deepRev: 1, parent };
+    obj.__owl__ = {
+      rev: this.rev,
+      deepRev: this.rev,
+      parent,
+      observer: this
+    };
     Object.defineProperty(obj, "__owl__", { enumerable: false });
-    for (let key of keys) {
+    for (let key in obj) {
       this._addProp(obj, key, obj[key]);
     }
   }
 
   _observeArr(arr: Array<any>, parent?: any) {
-    (<any>arr).__owl__ = { rev: 1, deepRev: 1, parent };
+    (<any>arr).__owl__ = {
+      rev: this.rev,
+      deepRev: this.rev,
+      parent,
+      observer: this
+    };
     Object.defineProperty(arr, "__owl__", { enumerable: false });
     (<any>arr).__proto__ = Object.create(ModifiedArrayProto);
     (<any>arr).__proto__.__observer__ = this;
-    for (let i = 0; i < arr.length; i++) {
+    for (let i = 0, iLen = arr.length; i < iLen; i++) {
       this.observe(arr[i], arr);
     }
   }
 
-  _addProp<T extends { __owl__?: any }>(
-    obj: T,
-    key: string | number,
-    value: any
-  ) {
+  _addProp<T extends { __owl__?: any }>(obj: T, key: string | number, value: any) {
     var self = this;
     Object.defineProperty(obj, key, {
+      configurable: true,
       enumerable: true,
       get() {
         return value;
@@ -126,17 +174,21 @@ export class Observer {
               `Observed state cannot be changed here! (key: "${key}", val: "${newVal}")`
             );
           }
+          self._updateRevNumber(obj);
           value = newVal;
           self.observe(newVal, obj);
-          obj.__owl__.rev!++;
-          let parent = obj;
-          do {
-            parent.__owl__.deepRev++;
-          } while ((parent = parent.__owl__.parent) && parent !== obj);
           self.notifyChange();
         }
       }
     });
     this.observe(value, obj);
   }
+  _updateRevNumber(target: any) {
+    this.rev++;
+    target.__owl__.rev!++;
+    let parent = target;
+    do {
+      parent.__owl__.deepRev++;
+    } while ((parent = parent.__owl__.parent) && parent !== target);
+  }
 }

src/qweb_core.ts

@@ -0,0 +1,751 @@
+import { VNode, h } from "./vdom";
+import { QWebVar, compileExpr } from "./qweb_expressions";
+import { EventBus } from "./event_bus";
+
+/**
+ * Owl QWeb Engine
+ *
+ * In this file, you will find a QWeb engine/template compiler.  It is the core
+ * of how Owl component works.
+ *
+ * Briefly, Owl QWeb compiles XML templates into functions that output a virtual
+ * DOM representation.
+ *
+ * We have here:
+ * - a CompilationContext class, which is an internal object that contains all
+ *   compilation specific information, while a template is being compiled.
+ * - a QWeb class: this is the code of the QWeb compiler.
+ *
+ * Note that this file does not contain the implementation of the QWeb
+ * directives (see qweb_directives.ts and qweb_extensions.ts).
+ */
+
+//------------------------------------------------------------------------------
+// Types
+//------------------------------------------------------------------------------
+export type EvalContext = { [key: string]: any };
+export type CompiledTemplate = (context: EvalContext, extra: any) => VNode;
+
+interface Template {
+  elem: Element;
+  fn: CompiledTemplate;
+}
+
+interface CompilationInfo {
+  node: Element;
+  qweb: QWeb;
+  ctx: Context;
+  fullName: string;
+  value: string;
+}
+
+interface NodeCreationCompilationInfo extends CompilationInfo {
+  nodeID: number;
+  addNodeHook: Function;
+}
+
+export interface Directive {
+  name: string;
+  extraNames?: string[];
+  priority: number;
+  // if return true, then directive is fully applied and there is no need to
+  // keep processing node. Otherwise, we keep going.
+  atNodeEncounter?(info: CompilationInfo): boolean | void;
+  atNodeCreation?(info: NodeCreationCompilationInfo): void;
+  finalize?(info: CompilationInfo): void;
+}
+
+//------------------------------------------------------------------------------
+// Const/global stuff/helpers
+//------------------------------------------------------------------------------
+
+const DISABLED_TAGS = ["input", "textarea", "button", "select", "option", "optgroup"];
+
+const lineBreakRE = /[\r\n]/;
+const whitespaceRE = /\s+/g;
+
+const DIRECTIVE_NAMES = {
+  name: 1,
+  att: 1,
+  attf: 1,
+  key: 1
+};
+
+const DIRECTIVES: Directive[] = [];
+
+const NODE_HOOKS_PARAMS = {
+  create: "(_, n)",
+  insert: "vn",
+  remove: "(vn, rm)"
+};
+
+interface Utils {
+  h: typeof h;
+  toObj(expr: any): Object;
+  shallowEqual(p1: Object, p2: Object): boolean;
+  [key: string]: any;
+}
+
+export const UTILS: Utils = {
+  h: h,
+  toObj(expr) {
+    if (typeof expr === "string") {
+      expr = expr.trim();
+      if (!expr) {
+        return {};
+      }
+      let words = expr.split(/\s+/);
+      let result = {};
+      for (let i = 0; i < words.length; i++) {
+        result[words[i]] = true;
+      }
+      return result;
+    }
+    return expr;
+  },
+  shallowEqual(p1, p2) {
+    for (let k in p1) {
+      if (p1[k] !== p2[k]) {
+        return false;
+      }
+    }
+    return true;
+  }
+};
+
+function parseXML(xml: string): Document {
+  const parser = new DOMParser();
+  const doc = parser.parseFromString(xml, "text/xml");
+  if (doc.getElementsByTagName("parsererror").length) {
+    throw new Error("Invalid XML in template");
+  }
+  return doc;
+}
+
+let nextID = 1;
+
+//------------------------------------------------------------------------------
+// QWeb rendering engine
+//------------------------------------------------------------------------------
+export class QWeb extends EventBus {
+  templates: { [name: string]: Template } = {};
+  utils = UTILS;
+  static components = Object.create(null);
+
+  // dev mode enables better error messages or more costly validations
+  static dev: boolean = false;
+
+  // the id field is useful to be able to hash qweb instances.  The current
+  // use case is that component's templates are qweb dependant, and need to be
+  // able to map a qweb instance to a template name.
+  id = nextID++;
+
+  // slots contains sub templates defined with t-set inside t-component nodes, and
+  // are meant to be used by the t-slot directive.
+  slots = {};
+  nextSlotId = 1;
+
+  constructor(data?: string) {
+    super();
+    if (data) {
+      this.addTemplates(data);
+    }
+  }
+
+  static addDirective(directive: Directive) {
+    DIRECTIVES.push(directive);
+    DIRECTIVE_NAMES[directive.name] = 1;
+    DIRECTIVES.sort((d1, d2) => d1.priority - d2.priority);
+    if (directive.extraNames) {
+      directive.extraNames.forEach(n => (DIRECTIVE_NAMES[n] = 1));
+    }
+  }
+
+  static register(name: string, Component: any) {
+    if (QWeb.components[name]) {
+      throw new Error(`Component '${name}' has already been registered`);
+    }
+    QWeb.components[name] = Component;
+  }
+
+  /**
+   * Add a template to the internal template map.  Note that it is not
+   * immediately compiled.
+   */
+  addTemplate(name: string, xmlString: string, allowDuplicate?: boolean) {
+    if (allowDuplicate && name in this.templates) {
+      return;
+    }
+    const doc = parseXML(xmlString);
+    if (!doc.firstChild) {
+      throw new Error("Invalid template (should not be empty)");
+    }
+    this._addTemplate(name, <Element>doc.firstChild);
+  }
+
+  /**
+   * Load templates from a xml (as a string).  This will look up for the first
+   * <templates> tag, and will consider each child of this as a template, with
+   * the name given by the t-name attribute.
+   */
+  addTemplates(xmlstr: string) {
+    const doc = parseXML(xmlstr);
+    const templates = doc.getElementsByTagName("templates")[0];
+    if (!templates) {
+      return;
+    }
+    for (let elem of <any>templates.children) {
+      const name = elem.getAttribute("t-name");
+      this._addTemplate(name, elem);
+    }
+  }
+
+  _addTemplate(name: string, elem: Element) {
+    if (name in this.templates) {
+      throw new Error(`Template ${name} already defined`);
+    }
+    this._processTemplate(elem);
+    const template = {
+      elem,
+      fn: (context, extra) => {
+        const compiledFunction = this._compile(name, elem);
+        template.fn = compiledFunction;
+        return compiledFunction.call(this, context, extra);
+      }
+    };
+    this.templates[name] = template;
+  }
+
+  _processTemplate(elem: Element) {
+    let tbranch = elem.querySelectorAll("[t-elif], [t-else]");
+    for (let i = 0, ilen = tbranch.length; i < ilen; i++) {
+      let node = tbranch[i];
+      let prevElem = node.previousElementSibling!;
+      let pattr = function(name) {
+        return prevElem.getAttribute(name);
+      };
+      let nattr = function(name) {
+        return +!!node.getAttribute(name);
+      };
+      if (prevElem && (pattr("t-if") || pattr("t-elif"))) {
+        if (pattr("t-foreach")) {
+          throw new Error(
+            "t-if cannot stay at the same level as t-foreach when using t-elif or t-else"
+          );
+        }
+        if (
+          ["t-if", "t-elif", "t-else"].map(nattr).reduce(function(a, b) {
+            return a + b;
+          }) > 1
+        ) {
+          throw new Error("Only one conditional branching directive is allowed per node");
+        }
+        // All text nodes between branch nodes are removed
+        let textNode;
+        while ((textNode = node.previousSibling) !== prevElem) {
+          if (textNode.nodeValue.trim().length) {
+            throw new Error("text is not allowed between branching directives");
+          }
+          textNode.remove();
+        }
+      } else {
+        throw new Error(
+          "t-elif and t-else directives must be preceded by a t-if or t-elif directive"
+        );
+      }
+    }
+  }
+  /**
+   * Render a template
+   *
+   * @param {string} name the template should already have been added
+   */
+  render(name: string, context: EvalContext = {}, extra: any = null): VNode {
+    const template = this.templates[name];
+    if (!template) {
+      throw new Error(`Template ${name} does not exist`);
+    }
+    return template.fn.call(this, context, extra);
+  }
+
+  _compile(name: string, elem: Element, parentNode?: number): CompiledTemplate {
+    const isDebug = elem.attributes.hasOwnProperty("t-debug");
+    const ctx = new Context(name);
+    if (parentNode) {
+      ctx.nextID = parentNode + 1;
+      ctx.parentNode = parentNode;
+      ctx.allowMultipleRoots = true;
+      ctx.addLine(`let c${parentNode} = extra.parentNode;`);
+    }
+    this._compileNode(elem, ctx);
+
+    if (ctx.shouldProtectContext) {
+      ctx.code.unshift("    context = Object.create(context);");
+    }
+    if (ctx.shouldDefineOwner) {
+      // this is necessary to prevent some directives (t-forach for ex) to
+      // pollute the rendering context by adding some keys in it.
+      ctx.code.unshift("    let owner = context;");
+    }
+    if (ctx.shouldDefineQWeb) {
+      ctx.code.unshift("    let QWeb = this.constructor;");
+    }
+    if (ctx.shouldDefineUtils) {
+      ctx.code.unshift("    let utils = this.utils;");
+    }
+
+    if (!parentNode) {
+      if (!ctx.rootNode) {
+        throw new Error("A template should have one root node");
+      }
+      ctx.addLine(`return vn${ctx.rootNode};`);
+    }
+    let template;
+    try {
+      template = new Function("context", "extra", ctx.code.join("\n")) as CompiledTemplate;
+    } catch (e) {
+      const templateName = ctx.templateName.replace(/`/g, "'");
+      console.groupCollapsed(`Invalid Code generated by ${templateName}`);
+      console.warn(ctx.code.join("\n"));
+      console.groupEnd();
+      throw new Error(
+        `Invalid generated code while compiling template '${templateName}': ${e.message}`
+      );
+    }
+    if (isDebug) {
+      const tpl = this.templates[name];
+      if (tpl) {
+        const msg = `Template: ${tpl.elem.outerHTML}\nCompiled code:\n${template.toString()}`;
+        console.log(msg);
+      }
+    }
+    return template;
+  }
+
+  /**
+   * Generate code from an xml node
+   *
+   */
+  _compileNode(node: ChildNode, ctx: Context) {
+    if (!(node instanceof Element)) {
+      // this is a text node, there are no directive to apply
+      let text = node.textContent!;
+      if (!ctx.inPreTag) {
+        if (lineBreakRE.test(text) && !text.trim()) {
+          return;
+        }
+        text = text.replace(whitespaceRE, " ");
+      }
+      if (ctx.parentNode) {
+        ctx.addLine(`c${ctx.parentNode}.push({text: \`${text}\`});`);
+      } else if (ctx.parentTextNode) {
+        ctx.addLine(`vn${ctx.parentTextNode}.text += \`${text}\`;`);
+      } else {
+        // this is an unusual situation: this text node is the result of the
+        // template rendering.
+        let nodeID = ctx.generateID();
+        ctx.addLine(`var vn${nodeID} = {text: \`${text}\`};`);
+        ctx.rootContext.rootNode = nodeID;
+        ctx.rootContext.parentTextNode = nodeID;
+      }
+      return;
+    }
+
+    const firstLetter = node.tagName[0];
+    if (firstLetter === firstLetter.toUpperCase()) {
+      // this is a component, we modify in place the xml document to change
+      // <SomeComponent ... /> to <t t-component="SomeComponent" ... />
+      node.setAttribute("t-component", node.tagName);
+    }
+    const attributes = (<Element>node).attributes;
+
+    const validDirectives: {
+      directive: Directive;
+      value: string;
+      fullName: string;
+    }[] = [];
+
+    let withHandlers = false;
+
+    // maybe this is not optimal: we iterate on all attributes here, and again
+    // just after for each directive.
+    for (let i = 0; i < attributes.length; i++) {
+      let attrName = attributes[i].name;
+      if (attrName.startsWith("t-")) {
+        let dName = attrName.slice(2).split(/-|\./)[0];
+        if (!(dName in DIRECTIVE_NAMES)) {
+          throw new Error(`Unknown QWeb directive: '${attrName}'`);
+        }
+      }
+    }
+
+    const DIR_N = DIRECTIVES.length;
+    const ATTR_N = attributes.length;
+    for (let i = 0; i < DIR_N; i++) {
+      let directive = DIRECTIVES[i];
+      let fullName;
+      let value;
+      for (let j = 0; j < ATTR_N; j++) {
+        const name = attributes[j].name;
+        if (
+          name === "t-" + directive.name ||
+          name.startsWith("t-" + directive.name + "-") ||
+          name.startsWith("t-" + directive.name + ".")
+        ) {
+          fullName = name;
+          value = attributes[j].textContent;
+          validDirectives.push({ directive, value, fullName });
+          if (directive.name === "on" || directive.name === "model") {
+            withHandlers = true;
+          }
+        }
+      }
+    }
+    for (let { directive, value, fullName } of validDirectives) {
+      if (directive.atNodeEncounter) {
+        const isDone = directive.atNodeEncounter({
+          node,
+          qweb: this,
+          ctx,
+          fullName,
+          value
+        });
+        if (isDone) {
+          return;
+        }
+      }
+    }
+
+    if (node.nodeName !== "t") {
+      let nodeID = this._compileGenericNode(node, ctx, withHandlers);
+      ctx = ctx.withParent(nodeID);
+      let nodeHooks = {};
+      let addNodeHook = function(hook, handler) {
+        nodeHooks[hook] = nodeHooks[hook] || [];
+        nodeHooks[hook].push(handler);
+      };
+
+      for (let { directive, value, fullName } of validDirectives) {
+        if (directive.atNodeCreation) {
+          directive.atNodeCreation({
+            node,
+            qweb: this,
+            ctx,
+            fullName,
+            value,
+            nodeID,
+            addNodeHook
+          });
+        }
+      }
+
+      if (Object.keys(nodeHooks).length) {
+        ctx.addLine(`p${nodeID}.hook = {`);
+        for (let hook in nodeHooks) {
+          ctx.addLine(`  ${hook}: ${NODE_HOOKS_PARAMS[hook]} => {`);
+          for (let handler of nodeHooks[hook]) {
+            ctx.addLine(`    ${handler}`);
+          }
+          ctx.addLine(`  },`);
+        }
+        ctx.addLine(`};`);
+      }
+    }
+    if (node.nodeName === "pre") {
+      ctx = ctx.subContext("inPreTag", true);
+    }
+
+    this._compileChildren(node, ctx);
+
+    for (let { directive, value, fullName } of validDirectives) {
+      if (directive.finalize) {
+        directive.finalize({ node, qweb: this, ctx, fullName, value });
+      }
+    }
+  }
+
+  _compileGenericNode(node: ChildNode, ctx: Context, withHandlers: boolean = true): number {
+    // nodeType 1 is generic tag
+    if (node.nodeType !== 1) {
+      throw new Error("unsupported node type");
+    }
+    const attributes = (<Element>node).attributes;
+    const attrs: string[] = [];
+    const props: string[] = [];
+    const tattrs: number[] = [];
+
+    function handleBooleanProps(key, val) {
+      let isProp = false;
+      if (node.nodeName === "input" && key === "checked") {
+        let type = (<Element>node).getAttribute("type");
+        if (type === "checkbox" || type === "radio") {
+          isProp = true;
+        }
+      }
+      if (node.nodeName === "option" && key === "selected") {
+        isProp = true;
+      }
+      if (key === "disabled" && DISABLED_TAGS.indexOf(node.nodeName) > -1) {
+        isProp = true;
+      }
+      if ((key === "readonly" && node.nodeName === "input") || node.nodeName === "textarea") {
+        isProp = true;
+      }
+      if (isProp) {
+        props.push(`${key}: _${val}`);
+      }
+    }
+    let classObj = "";
+
+    for (let i = 0; i < attributes.length; i++) {
+      let name = attributes[i].name;
+      const value = attributes[i].textContent!;
+
+      // regular attributes
+      if (!name.startsWith("t-") && !(<Element>node).getAttribute("t-attf-" + name)) {
+        const attID = ctx.generateID();
+        if (name === "class") {
+          let classDef = value
+            .trim()
+            .split(/\s+/)
+            .map(a => `'${a}':true`)
+            .join(",");
+          classObj = `_${ctx.generateID()}`;
+          ctx.addLine(`let ${classObj} = {${classDef}};`);
+        } else {
+          ctx.addLine(`var _${attID} = '${value}';`);
+          if (!name.match(/^[a-zA-Z]+$/)) {
+            // attribute contains 'non letters' => we want to quote it
+            name = '"' + name + '"';
+          }
+          attrs.push(`${name}: _${attID}`);
+          handleBooleanProps(name, attID);
+        }
+      }
+
+      // dynamic attributes
+      if (name.startsWith("t-att-")) {
+        let attName = name.slice(6);
+        const v = ctx.getValue(value);
+        let formattedValue = v.id || ctx.formatExpression(v);
+
+        if (attName === "class") {
+          formattedValue = `this.utils.toObj(${formattedValue})`;
+          if (classObj) {
+            ctx.addLine(`Object.assign(${classObj}, ${formattedValue})`);
+          } else {
+            classObj = `_${ctx.generateID()}`;
+            ctx.addLine(`let ${classObj} = ${formattedValue};`);
+          }
+        } else {
+          const attID = ctx.generateID();
+          if (!attName.match(/^[a-zA-Z]+$/)) {
+            // attribute contains 'non letters' => we want to quote it
+            attName = '"' + attName + '"';
+          }
+          // we need to combine dynamic with non dynamic attributes:
+          // class="a" t-att-class="'yop'" should be rendered as class="a yop"
+          const attValue = (<Element>node).getAttribute(attName);
+          if (attValue) {
+            const attValueID = ctx.generateID();
+            ctx.addLine(`var _${attValueID} = ${formattedValue};`);
+            formattedValue = `'${attValue}' + (_${attValueID} ? ' ' + _${attValueID} : '')`;
+            const attrIndex = attrs.findIndex(att => att.startsWith(attName + ":"));
+            attrs.splice(attrIndex, 1);
+          }
+          ctx.addLine(`var _${attID} = ${formattedValue};`);
+          attrs.push(`${attName}: _${attID}`);
+          handleBooleanProps(attName, attID);
+        }
+      }
+
+      if (name.startsWith("t-attf-")) {
+        let attName = name.slice(7);
+        if (!attName.match(/^[a-zA-Z]+$/)) {
+          // attribute contains 'non letters' => we want to quote it
+          attName = '"' + attName + '"';
+        }
+        const formattedExpr = ctx.interpolate(value);
+        const attID = ctx.generateID();
+        let staticVal = (<Element>node).getAttribute(attName);
+        if (staticVal) {
+          ctx.addLine(`var _${attID} = '${staticVal} ' + ${formattedExpr};`);
+        } else {
+          ctx.addLine(`var _${attID} = ${formattedExpr};`);
+        }
+        attrs.push(`${attName}: _${attID}`);
+      }
+
+      // t-att= attributes
+      if (name === "t-att") {
+        let id = ctx.generateID();
+        ctx.addLine(`var _${id} = ${ctx.formatExpression(value!)};`);
+        tattrs.push(id);
+      }
+    }
+    let nodeID = ctx.generateID();
+    let nodeKey: any = (<Element>node).getAttribute("t-key");
+    if (nodeKey) {
+      nodeKey = ctx.formatExpression(nodeKey);
+    } else {
+      nodeKey = nodeID;
+    }
+    const parts = [`key:${nodeKey}`];
+    if (attrs.length + tattrs.length > 0) {
+      parts.push(`attrs:{${attrs.join(",")}}`);
+    }
+    if (props.length > 0) {
+      parts.push(`props:{${props.join(",")}}`);
+    }
+    if (classObj) {
+      parts.push(`class:${classObj}`);
+    }
+    if (withHandlers) {
+      parts.push(`on:{}`);
+    }
+
+    ctx.addLine(`let c${nodeID} = [], p${nodeID} = {${parts.join(",")}};`);
+    for (let id of tattrs) {
+      ctx.addIf(`_${id} instanceof Array`);
+      ctx.addLine(`p${nodeID}.attrs[_${id}[0]] = _${id}[1];`);
+      ctx.addElse();
+      ctx.addLine(`for (let key in _${id}) {`);
+      ctx.indent();
+      ctx.addLine(`p${nodeID}.attrs[key] = _${id}[key];`);
+      ctx.dedent();
+      ctx.addLine(`}`);
+      ctx.closeIf();
+    }
+    ctx.addLine(`var vn${nodeID} = h('${node.nodeName}', p${nodeID}, c${nodeID});`);
+    if (ctx.parentNode) {
+      ctx.addLine(`c${ctx.parentNode}.push(vn${nodeID});`);
+    }
+
+    return nodeID;
+  }
+
+  _compileChildren(node: ChildNode, ctx: Context) {
+    if (node.childNodes.length > 0) {
+      for (let child of Array.from(node.childNodes)) {
+        this._compileNode(child, ctx);
+      }
+    }
+  }
+}
+
+//------------------------------------------------------------------------------
+// Compilation Context
+//------------------------------------------------------------------------------
+
+export class Context {
+  nextID: number = 1;
+  code: string[] = [];
+  variables: { [key: string]: QWebVar } = {};
+  escaping: boolean = false;
+  parentNode: number | null = null;
+  parentTextNode: number | null = null;
+  rootNode: number | null = null;
+  indentLevel: number = 0;
+  rootContext: Context;
+  caller: Element | undefined;
+  shouldDefineOwner: boolean = false;
+  shouldDefineQWeb: boolean = false;
+  shouldDefineUtils: boolean = false;
+  shouldProtectContext: boolean = false;
+  inLoop: boolean = false;
+  inPreTag: boolean = false;
+  templateName: string;
+  allowMultipleRoots: boolean = false;
+
+  constructor(name?: string) {
+    this.rootContext = this;
+    this.templateName = name || "noname";
+    this.addLine("var h = this.utils.h;");
+  }
+
+  generateID(): number {
+    const id = this.rootContext.nextID++;
+    return id;
+  }
+
+  withParent(node: number): Context {
+    if (
+      !this.allowMultipleRoots &&
+      this === this.rootContext &&
+      (this.parentNode || this.parentTextNode)
+    ) {
+      throw new Error("A template should not have more than one root node");
+    }
+    if (!this.rootContext.rootNode) {
+      this.rootContext.rootNode = node;
+    }
+    return this.subContext("parentNode", node);
+  }
+
+  subContext(key: keyof Context, value: any): Context {
+    const newContext = Object.create(this);
+    newContext[key] = value;
+    return newContext;
+  }
+
+  indent() {
+    this.indentLevel++;
+  }
+
+  dedent() {
+    this.indentLevel--;
+  }
+
+  addLine(line: string) {
+    const prefix = new Array(this.indentLevel + 2).join("    ");
+    this.code.push(prefix + line);
+  }
+
+  addIf(condition: string) {
+    this.addLine(`if (${condition}) {`);
+    this.indent();
+  }
+
+  addElse() {
+    this.dedent();
+    this.addLine("} else {");
+    this.indent();
+  }
+
+  closeIf() {
+    this.dedent();
+    this.addLine("}");
+  }
+
+  getValue(val: any): any {
+    return val in this.variables ? this.getValue(this.variables[val]) : val;
+  }
+
+  /**
+   * Prepare an expression for being consumed at render time.  Its main job
+   * is to
+   * - replace unknown variables by a lookup in the context
+   * - replace already defined variables by their internal name
+   */
+  formatExpression(expr: string): string {
+    return compileExpr(expr, this.variables);
+  }
+
+  /**
+   * Perform string interpolation on the given string. Note that if the whole
+   * string is an expression, it simply returns it (formatted and enclosed in
+   * parentheses).
+   * For instance:
+   *   'Hello {{x}}!' -> `Hello ${x}`
+   *   '{{x ? 'a': 'b'}}' -> (x ? 'a' : 'b')
+   */
+  interpolate(s: string): string {
+    let matches = s.match(/\{\{.*?\}\}/g);
+    if (matches && matches[0].length === s.length) {
+      return `(${this.formatExpression(s.slice(2, -2))})`;
+    }
+
+    let r = s.replace(/\{\{.*?\}\}/g, s => "${" + this.formatExpression(s.slice(2, -2)) + "}");
+    return "`" + r + "`";
+  }
+}

src/qweb_directives.ts

@@ -0,0 +1,314 @@
+import { Context, QWeb, UTILS } from "./qweb_core";
+import { QWebExprVar } from "./qweb_expressions";
+
+/**
+ * Owl QWeb Directives
+ *
+ * This file contains the implementation of most standard QWeb directives:
+ * - t-esc
+ * - t-raw
+ * - t-set/t-value
+ * - t-if/t-elif/t-else
+ * - t-call
+ * - t-foreach/t-as
+ * - t-debug
+ * - t-log
+ */
+
+//------------------------------------------------------------------------------
+// t-esc and t-raw
+//------------------------------------------------------------------------------
+(<any>UTILS).getFragment = function(str: string): DocumentFragment {
+  const temp = document.createElement("template");
+  temp.innerHTML = str;
+  return temp.content;
+};
+
+function compileValueNode(value: any, node: Element, qweb: QWeb, ctx: Context) {
+  if (value === "0" && ctx.caller) {
+    qweb._compileNode(ctx.caller, ctx);
+    return;
+  }
+
+  if (value.xml instanceof NodeList) {
+    for (let node of Array.from(value.xml)) {
+      qweb._compileNode(<ChildNode>node, ctx);
+    }
+    return;
+  }
+  let exprID: string;
+  if (typeof value === "string") {
+    exprID = `_${ctx.generateID()}`;
+    ctx.addLine(`var ${exprID} = ${ctx.formatExpression(value)};`);
+  } else {
+    exprID = value.id;
+  }
+  ctx.addIf(`${exprID} || ${exprID} === 0`);
+  if (ctx.escaping) {
+    if (ctx.parentTextNode) {
+      ctx.addLine(`vn${ctx.parentTextNode}.text += ${exprID};`);
+    } else if (ctx.parentNode) {
+      ctx.addLine(`c${ctx.parentNode}.push({text: ${exprID}});`);
+    } else {
+      let nodeID = ctx.generateID();
+      ctx.rootContext.rootNode = nodeID;
+      ctx.rootContext.parentTextNode = nodeID;
+      ctx.addLine(`var vn${nodeID} = {text: ${exprID}};`);
+    }
+  } else {
+    let fragID = ctx.generateID();
+    ctx.addLine(`var frag${fragID} = this.utils.getFragment(${exprID})`);
+    let tempNodeID = ctx.generateID();
+    ctx.addLine(`var p${tempNodeID} = {hook: {`);
+    ctx.addLine(`  insert: n => n.elm.parentNode.replaceChild(frag${fragID}, n.elm),`);
+    ctx.addLine(`}};`);
+    ctx.addLine(`var vn${tempNodeID} = h('div', p${tempNodeID})`);
+    ctx.addLine(`c${ctx.parentNode}.push(vn${tempNodeID});`);
+  }
+  if (node.childNodes.length) {
+    ctx.addElse();
+    qweb._compileChildren(node, ctx);
+  }
+
+  ctx.closeIf();
+}
+
+QWeb.addDirective({
+  name: "esc",
+  priority: 70,
+  atNodeEncounter({ node, qweb, ctx }): boolean {
+    if (node.nodeName !== "t") {
+      let nodeID = qweb._compileGenericNode(node, ctx);
+      ctx = ctx.withParent(nodeID);
+    }
+    let value = ctx.getValue(node.getAttribute("t-esc")!);
+    compileValueNode(value, node, qweb, ctx.subContext("escaping", true));
+    return true;
+  }
+});
+
+QWeb.addDirective({
+  name: "raw",
+  priority: 80,
+  atNodeEncounter({ node, qweb, ctx }): boolean {
+    if (node.nodeName !== "t") {
+      let nodeID = qweb._compileGenericNode(node, ctx);
+      ctx = ctx.withParent(nodeID);
+    }
+    let value = ctx.getValue(node.getAttribute("t-raw")!);
+    compileValueNode(value, node, qweb, ctx);
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-set
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "set",
+  extraNames: ["value"],
+  priority: 60,
+  atNodeEncounter({ node, ctx }): boolean {
+    const variable = node.getAttribute("t-set")!;
+    let value = node.getAttribute("t-value")!;
+    if (value) {
+      const formattedValue = ctx.formatExpression(value);
+      if (ctx.variables.hasOwnProperty(variable)) {
+        ctx.addLine(`${(<QWebExprVar>ctx.variables[variable]).id} = ${formattedValue}`);
+      } else {
+        const varName = `_${ctx.generateID()}`;
+        ctx.addLine(`var ${varName} = ${formattedValue};`);
+        ctx.variables[variable] = {
+          id: varName,
+          expr: formattedValue
+        };
+      }
+    } else {
+      ctx.variables[variable] = {
+        xml: node.childNodes
+      };
+    }
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-if, t-elif, t-else
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "if",
+  priority: 20,
+  atNodeEncounter({ node, ctx }): boolean {
+    let cond = ctx.getValue(node.getAttribute("t-if")!);
+    ctx.addIf(`${ctx.formatExpression(cond)}`);
+    return false;
+  },
+  finalize({ ctx }) {
+    ctx.closeIf();
+  }
+});
+
+QWeb.addDirective({
+  name: "elif",
+  priority: 30,
+  atNodeEncounter({ node, ctx }): boolean {
+    let cond = ctx.getValue(node.getAttribute("t-elif")!);
+    ctx.addLine(`else if (${ctx.formatExpression(cond)}) {`);
+    ctx.indent();
+    return false;
+  },
+  finalize({ ctx }) {
+    ctx.closeIf();
+  }
+});
+
+QWeb.addDirective({
+  name: "else",
+  priority: 40,
+  atNodeEncounter({ ctx }): boolean {
+    ctx.addLine(`else {`);
+    ctx.indent();
+    return false;
+  },
+  finalize({ ctx }) {
+    ctx.closeIf();
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-call
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "call",
+  priority: 50,
+  atNodeEncounter({ node, qweb, ctx }): boolean {
+    if (node.nodeName !== "t") {
+      throw new Error("Invalid tag for t-call directive (should be 't')");
+    }
+    const subTemplate = node.getAttribute("t-call")!;
+    const nodeTemplate = qweb.templates[subTemplate];
+    if (!nodeTemplate) {
+      throw new Error(`Cannot find template "${subTemplate}" (t-call)`);
+    }
+    const nodeCopy = node.cloneNode(true) as Element;
+    nodeCopy.removeAttribute("t-call");
+
+    // extract variables from nodecopy
+    const tempCtx = new Context();
+    tempCtx.nextID = ctx.rootContext.nextID;
+    qweb._compileNode(nodeCopy, tempCtx);
+    const vars = Object.assign({}, ctx.variables, tempCtx.variables);
+    ctx.rootContext.nextID = tempCtx.nextID;
+
+    // open new scope, if necessary
+    const hasNewVariables = Object.keys(tempCtx.variables).length > 0;
+    if (hasNewVariables) {
+      ctx.addLine("{");
+      ctx.indent();
+      // add new variables, if any
+      for (let key in tempCtx.variables) {
+        const v = tempCtx.variables[key];
+        if ((<QWebExprVar>v).expr) {
+          ctx.addLine(`let ${(<QWebExprVar>v).id} = ${(<QWebExprVar>v).expr};`);
+        }
+        // todo: handle XML variables...
+      }
+    }
+
+    // compile sub template
+    const subCtx = ctx.subContext("caller", nodeCopy).subContext("variables", Object.create(vars));
+
+    qweb._compileNode(nodeTemplate.elem, subCtx);
+
+    // close new scope
+    if (hasNewVariables) {
+      ctx.dedent();
+      ctx.addLine("}");
+    }
+
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-foreach
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "foreach",
+  extraNames: ["as"],
+  priority: 10,
+  atNodeEncounter({ node, qweb, ctx }): boolean {
+    ctx.rootContext.shouldProtectContext = true;
+    ctx = ctx.subContext("inLoop", true);
+    const elems = node.getAttribute("t-foreach")!;
+    const name = node.getAttribute("t-as")!;
+    let arrayID = ctx.generateID();
+    ctx.addLine(`var _${arrayID} = ${ctx.formatExpression(elems)};`);
+    ctx.addLine(`if (!_${arrayID}) { throw new Error('QWeb error: Invalid loop expression')}`);
+    let keysID = ctx.generateID();
+    let valuesID = ctx.generateID();
+    ctx.addLine(`var _${keysID} = _${valuesID} = _${arrayID};`);
+    ctx.addIf(`!(_${arrayID} instanceof Array)`);
+    ctx.addLine(`_${keysID} = Object.keys(_${arrayID});`);
+    ctx.addLine(`_${valuesID} = Object.values(_${arrayID});`);
+    ctx.closeIf();
+    ctx.addLine(`var _length${keysID} = _${keysID}.length;`);
+    ctx.addLine(`for (let i = 0; i < _length${keysID}; i++) {`);
+    ctx.indent();
+    ctx.addLine(`context.${name}_first = i === 0;`);
+    ctx.addLine(`context.${name}_last = i === _length${keysID} - 1;`);
+    ctx.addLine(`context.${name}_index = i;`);
+    ctx.addLine(`context.${name} = _${keysID}[i];`);
+    ctx.addLine(`context.${name}_value = _${valuesID}[i];`);
+    const nodeCopy = <Element>node.cloneNode(true);
+    let shouldWarn = nodeCopy.tagName !== "t" && !nodeCopy.hasAttribute("t-key");
+    if (!shouldWarn && node.tagName === "t") {
+      if (node.hasAttribute("t-component") && !node.hasAttribute("t-key")) {
+        shouldWarn = true;
+      }
+      if (
+        !shouldWarn &&
+        node.children.length === 1 &&
+        node.children[0].tagName !== "t" &&
+        !node.children[0].hasAttribute("t-key")
+      ) {
+        shouldWarn = true;
+      }
+    }
+    if (shouldWarn) {
+      console.warn(
+        `Directive t-foreach should always be used with a t-key! (in template: '${
+          ctx.templateName
+        }')`
+      );
+    }
+    nodeCopy.removeAttribute("t-foreach");
+    qweb._compileNode(nodeCopy, ctx);
+    ctx.dedent();
+    ctx.addLine("}");
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-debug
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "debug",
+  priority: 1,
+  atNodeEncounter({ ctx }) {
+    ctx.addLine("debugger;");
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-log
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "log",
+  priority: 1,
+  atNodeEncounter({ ctx, value }) {
+    const expr = ctx.formatExpression(value);
+    ctx.addLine(`console.log(${expr})`);
+  }
+});

src/qweb_expressions.ts

@@ -0,0 +1,264 @@
+/**
+ * Owl QWeb Expression Parser
+ *
+ * Owl needs in various contexts to be able to understand the structure of a
+ * string representing a javascript expression.  The usual goal is to be able
+ * to rewrite some variables.  For example, if a template has
+ *
+ *  ```xml
+ *  <t t-if="computeSomething({val: state.val})">...</t>
+ * ```
+ *
+ * this needs to be translated in something like this:
+ *
+ * ```js
+ *   if (context["computeSomething"]({val: context["state"].val})) { ... }
+ * ```
+ *
+ * This file contains the implementation of an extremely naive tokenizer/parser
+ * and evaluator for javascript expressions.  The supported grammar is basically
+ * only expressive enough to understand the shape of objects, of arrays, and
+ * various operators.
+ */
+
+//------------------------------------------------------------------------------
+// Misc types, constants and helpers
+//------------------------------------------------------------------------------
+
+const RESERVED_WORDS = "true,false,NaN,null,undefined,debugger,console,window,in,instanceof,new,function,return,this,typeof,eval,void,Math,RegExp,Array,Object,Date".split(
+  ","
+);
+
+const WORD_REPLACEMENT = {
+  and: "&&",
+  or: "||",
+  gt: ">",
+  gte: ">=",
+  lt: "<",
+  lte: "<="
+};
+
+export interface QWebExprVar {
+  id: string;
+  expr: string;
+}
+
+export interface QWebXMLVar {
+  xml: NodeList;
+}
+
+export type QWebVar = QWebExprVar | QWebXMLVar;
+
+//------------------------------------------------------------------------------
+// Tokenizer
+//------------------------------------------------------------------------------
+type TKind =
+  | "LEFT_BRACE"
+  | "RIGHT_BRACE"
+  | "LEFT_BRACKET"
+  | "RIGHT_BRACKET"
+  | "LEFT_PAREN"
+  | "RIGHT_PAREN"
+  | "COMMA"
+  | "VALUE"
+  | "SYMBOL"
+  | "OPERATOR"
+  | "COLON";
+
+interface Token {
+  type: TKind;
+  value: string;
+  size?: number;
+}
+
+const STATIC_TOKEN_MAP: { [key: string]: TKind } = {
+  "{": "LEFT_BRACE",
+  "}": "RIGHT_BRACE",
+  "[": "LEFT_BRACKET",
+  "]": "RIGHT_BRACKET",
+  ":": "COLON",
+  ",": "COMMA",
+  "(": "LEFT_PAREN",
+  ")": "RIGHT_PAREN"
+};
+
+const OPERATORS = ".,===,==,+,!==,!=,!,||,&&,>=,>,<=,<,?,-,*,/,%".split(",");
+
+type Tokenizer = (expr: string) => Token | false;
+
+let tokenizeString: Tokenizer = function(expr) {
+  let s = expr[0];
+  let start = s;
+  if (s !== "'" && s !== '"') {
+    return false;
+  }
+  let i = 1;
+  let cur;
+  while (expr[i] && expr[i] !== start) {
+    cur = expr[i];
+    s += cur;
+    if (cur === "\\") {
+      i++;
+      cur = expr[i];
+      if (!cur) {
+        throw new Error("Invalid expression");
+      }
+      s += cur;
+    }
+    i++;
+  }
+  if (expr[i] !== start) {
+    throw new Error("Invalid expression");
+  }
+  s += start;
+  return { type: "VALUE", value: s };
+};
+
+let tokenizeNumber: Tokenizer = function(expr) {
+  let s = expr[0];
+  if (s && s.match(/[0-9]/)) {
+    let i = 1;
+    while (expr[i] && expr[i].match(/[0-9]|\./)) {
+      s += expr[i];
+      i++;
+    }
+    return { type: "VALUE", value: s };
+  } else {
+    return false;
+  }
+};
+
+let tokenizeSymbol: Tokenizer = function(expr) {
+  let s = expr[0];
+  if (s && s.match(/[a-zA-Z_\$]/)) {
+    let i = 1;
+    while (expr[i] && expr[i].match(/\w/)) {
+      s += expr[i];
+      i++;
+    }
+    if (s in WORD_REPLACEMENT) {
+      return { type: "OPERATOR", value: WORD_REPLACEMENT[s], size: s.length };
+    }
+    return { type: "SYMBOL", value: s };
+  } else {
+    return false;
+  }
+};
+
+const tokenizeStatic: Tokenizer = function(expr) {
+  const char = expr[0];
+  if (char && char in STATIC_TOKEN_MAP) {
+    return { type: STATIC_TOKEN_MAP[char], value: char };
+  }
+  return false;
+};
+
+const tokenizeOperator: Tokenizer = function(expr) {
+  for (let op of OPERATORS) {
+    if (expr.startsWith(op)) {
+      return { type: "OPERATOR", value: op };
+    }
+  }
+  return false;
+};
+
+const TOKENIZERS = [
+  tokenizeString,
+  tokenizeNumber,
+  tokenizeSymbol,
+  tokenizeStatic,
+  tokenizeOperator
+];
+
+/**
+ * Convert a javascript expression (as a string) into a list of tokens. For
+ * example: `tokenize("1 + b")` will return:
+ * ```js
+ *  [
+ *   {type: "VALUE", value: "1"},
+ *   {type: "OPERATOR", value: "+"},
+ *   {type: "SYMBOL", value: "b"}
+ * ]
+ * ```
+ */
+export function tokenize(expr: string): Token[] {
+  const result: Token[] = [];
+  let token: boolean | Token = true;
+
+  while (token) {
+    expr = expr.trim();
+    if (expr) {
+      for (let tokenizer of TOKENIZERS) {
+        token = tokenizer(expr);
+        if (token) {
+          result.push(token);
+          expr = expr.slice(token.size || token.value.length);
+          break;
+        }
+      }
+    } else {
+      token = false;
+    }
+  }
+  if (expr.length) {
+    throw new Error(`Tokenizer error: could not tokenize "${expr}"`);
+  }
+  return result;
+}
+
+//------------------------------------------------------------------------------
+// Expression "evaluator"
+//------------------------------------------------------------------------------
+
+/**
+ * This is the main function exported by this file. This is the code that will
+ * process an expression (given as a string) and returns another expression with
+ * proper lookups in the context.
+ *
+ * Usually, this kind of code would be very simple to do if we had an AST (so,
+ * if we had a javascript parser), since then, we would only need to find the
+ * variables and replace them.  However, a parser is more complicated, and there
+ * are no standard builtin parser API.
+ *
+ * Since this method is applied to simple javasript expressions, and the work to
+ * be done is actually quite simple, we actually can get away with not using a
+ * parser, which helps with the code size.
+ *
+ * Here is the heuristic used by this method to determine if a token is a
+ * variable:
+ * - by default, all symbols are considered a variable
+ * - unless the previous token is a dot (in that case, this is a property: `a.b`)
+ * - or if the previous token is a left brace or a comma, and the next token is
+ *   a colon (in that case, this is an object key: `{a: b}`)
+ */
+export function compileExpr(expr: string, vars: { [key: string]: QWebVar }): string {
+  const tokens = tokenize(expr);
+  let result = "";
+  for (let i = 0; i < tokens.length; i++) {
+    let token = tokens[i];
+    if (token.type === "SYMBOL" && !RESERVED_WORDS.includes(token.value)) {
+      // we need to find if it is a variable
+      let isVar = true;
+      let prevToken = tokens[i - 1];
+      if (prevToken) {
+        if (prevToken.type === "OPERATOR" && prevToken.value === ".") {
+          isVar = false;
+        } else if (prevToken.type === "LEFT_BRACE" || prevToken.type === "COMMA") {
+          let nextToken = tokens[i + 1];
+          if (nextToken && nextToken.type === "COLON") {
+            isVar = false;
+          }
+        }
+      }
+      if (isVar) {
+        if (token.value in vars && "id" in vars[token.value]) {
+          token.value = (<QWebExprVar>vars[token.value]).id;
+        } else {
+          token.value = `context['${token.value}']`;
+        }
+      }
+    }
+    result += token.value;
+  }
+  return result;
+}

src/qweb_extensions.ts

@@ -0,0 +1,727 @@
+import { QWeb, UTILS } from "./qweb_core";
+import { VNode } from "./vdom";
+
+/**
+ * Owl QWeb Extensions
+ *
+ * This file contains the implementation of non standard QWeb directives, added
+ * by Owl and that will only work on Owl projects:
+ *
+ * - t-on
+ * - t-ref
+ * - t-transition
+ * - t-component/t-keepalive
+ * - t-mounted
+ * - t-slot
+ * - t-model
+ */
+
+//------------------------------------------------------------------------------
+// t-on
+//------------------------------------------------------------------------------
+// these are pieces of code that will be injected into the event handler if
+// modifiers are specified
+const MODS_CODE = {
+  prevent: "e.preventDefault();",
+  self: "if (e.target !== this.elm) {return}",
+  stop: "e.stopPropagation();"
+};
+
+QWeb.addDirective({
+  name: "on",
+  priority: 90,
+  atNodeCreation({ ctx, fullName, value, nodeID }) {
+    ctx.rootContext.shouldDefineOwner = true;
+    const [eventName, ...mods] = fullName.slice(5).split(".");
+    if (!eventName) {
+      throw new Error("Missing event name with t-on directive");
+    }
+    let extraArgs;
+    let handlerName = value.replace(/\(.*\)/, function(args) {
+      extraArgs = args.slice(1, -1);
+      return "";
+    });
+    ctx.addIf(`!context['${handlerName}']`);
+    ctx.addLine(
+      `throw new Error('Missing handler \\'' + '${handlerName}' + \`\\' when evaluating template '${ctx.templateName.replace(
+        /`/g,
+        "'"
+      )}'\`)`
+    );
+    ctx.closeIf();
+    let params = extraArgs ? `owner, ${ctx.formatExpression(extraArgs)}` : "owner";
+    let handler;
+    if (mods.length > 0) {
+      handler = `function (e) {`;
+      handler += mods
+        .map(function(mod) {
+          return MODS_CODE[mod];
+        })
+        .join("");
+      handler += `context['${handlerName}'].call(${params}, e);}`;
+    } else {
+      handler = `context['${handlerName}'].bind(${params})`;
+    }
+    if (extraArgs) {
+      ctx.addLine(`p${nodeID}.on['${eventName}'] = ${handler};`);
+    } else {
+      ctx.addLine(
+        `extra.handlers['${eventName}' + ${nodeID}] = extra.handlers['${eventName}' + ${nodeID}] || ${handler};`
+      );
+      ctx.addLine(`p${nodeID}.on['${eventName}'] = extra.handlers['${eventName}' + ${nodeID}];`);
+    }
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-ref
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "ref",
+  priority: 95,
+  atNodeCreation({ ctx, value, addNodeHook }) {
+    const refKey = `ref${ctx.generateID()}`;
+    ctx.addLine(`const ${refKey} = ${ctx.interpolate(value)};`);
+    addNodeHook("create", `context.refs[${refKey}] = n.elm;`);
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-transition
+//------------------------------------------------------------------------------
+UTILS.nextFrame = function(cb: () => void) {
+  requestAnimationFrame(() => requestAnimationFrame(cb));
+};
+
+UTILS.transitionInsert = function(vn: VNode, name: string) {
+  const elm = <HTMLElement>vn.elm;
+  // remove potential duplicated vnode that is currently being removed, to
+  // prevent from having twice the same node in the DOM during an animation
+  const dup = elm.parentElement && elm.parentElement!.querySelector(`*[data-owl-key='${vn.key}']`);
+  if (dup) {
+    dup.remove();
+  }
+
+  elm.classList.add(name + "-enter");
+  elm.classList.add(name + "-enter-active");
+  const finalize = () => {
+    elm.classList.remove(name + "-enter-active");
+    elm.classList.remove(name + "-enter-to");
+  };
+  this.nextFrame(() => {
+    elm.classList.remove(name + "-enter");
+    elm.classList.add(name + "-enter-to");
+    whenTransitionEnd(elm, finalize);
+  });
+};
+
+UTILS.transitionRemove = function(vn: VNode, name: string, rm: () => void) {
+  const elm = <HTMLElement>vn.elm;
+  elm.setAttribute("data-owl-key", vn.key!);
+
+  elm.classList.add(name + "-leave");
+  elm.classList.add(name + "-leave-active");
+  const finalize = () => {
+    elm.classList.remove(name + "-leave-active");
+    elm.classList.remove(name + "-leave-to");
+    rm();
+  };
+  this.nextFrame(() => {
+    elm.classList.remove(name + "-leave");
+    elm.classList.add(name + "-leave-to");
+    whenTransitionEnd(elm, finalize);
+  });
+};
+
+function getTimeout(delays: Array<string>, durations: Array<string>): number {
+  /* istanbul ignore next */
+  while (delays.length < durations.length) {
+    delays = delays.concat(delays);
+  }
+
+  return Math.max.apply(
+    null,
+    durations.map((d, i) => {
+      return toMs(d) + toMs(delays[i]);
+    })
+  );
+}
+
+// Old versions of Chromium (below 61.0.3163.100) formats floating pointer numbers
+// in a locale-dependent way, using a comma instead of a dot.
+// If comma is not replaced with a dot, the input will be rounded down (i.e. acting
+// as a floor function) causing unexpected behaviors
+function toMs(s: string): number {
+  return Number(s.slice(0, -1).replace(",", ".")) * 1000;
+}
+
+function whenTransitionEnd(elm: HTMLElement, cb) {
+  const styles = window.getComputedStyle(elm);
+  const delays: Array<string> = (styles.transitionDelay || "").split(", ");
+  const durations: Array<string> = (styles.transitionDuration || "").split(", ");
+  const timeout: number = getTimeout(delays, durations);
+  if (timeout > 0) {
+    elm.addEventListener("transitionend", cb, { once: true });
+  } else {
+    cb();
+  }
+}
+
+QWeb.addDirective({
+  name: "transition",
+  priority: 96,
+  atNodeCreation({ value, addNodeHook }) {
+    let name = value;
+    const hooks = {
+      insert: `this.utils.transitionInsert(vn, '${name}');`,
+      remove: `this.utils.transitionRemove(vn, '${name}', rm);`
+    };
+    for (let hookName in hooks) {
+      addNodeHook(hookName, hooks[hookName]);
+    }
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-component
+//------------------------------------------------------------------------------
+
+const T_COMPONENT_MODS_CODE = Object.assign({}, MODS_CODE, {
+  self: "if (e.target !== vn.elm) {return}"
+});
+
+/**
+ * The t-component directive is certainly a complicated and hard to maintain piece
+ * of code.  To help you, fellow developer, if you have to maintain it, I offer
+ * you this advice: Good luck...
+ *
+ * Since it is not 'direct' code, but rather code that generates other code, it
+ * is not easy to understand.  To help you, here  is a detailed and commented
+ * explanation of the code generated by the t-component directive for the following
+ * situation:
+ * ```xml
+ *   <Child
+ *      t-key="'somestring'"
+ *      flag="state.flag"
+ *      t-transition="fade"/>
+ * ```
+ *
+ * ```js
+ * // we assign utils on top of the function because it will be useful for
+ * // each components
+ * let utils = this.utils;
+ *
+ * // this is the virtual node representing the parent div
+ * let c1 = [], p1 = { key: 1 };
+ * var vn1 = h("div", p1, c1);
+ *
+ * // t-component directive: we start by evaluating the expression given by t-key:
+ * let key5 = "somestring";
+ *
+ * // def3 is the promise that will contain later either the new component
+ * // creation, or the props update...
+ * let def3;
+ *
+ * // this is kind of tricky: we need here to find if the component was already
+ * // created by a previous rendering.  This is done by checking the internal
+ * // `cmap` (children map) of the parent component: it maps keys to component ids,
+ * // and, then, if there is an id, we look into the children list to get the
+ * // instance
+ * let w4 =
+ *   key5 in context.__owl__.cmap
+ *   ? context.__owl__.children[context.__owl__.cmap[key5]]
+ *   : false;
+ *
+ * // We keep the index of the position of the component in the closure.  We push
+ * // null to reserve the slot, and will replace it later by the component vnode,
+ * // when it will be ready (do not forget that preparing/rendering a component is
+ * // asynchronous)
+ * let _2_index = c1.length;
+ * c1.push(null);
+ *
+ * // we evaluate here the props given to the component. It is done here to be
+ * // able to easily reference it later, and also, it might be an expensive
+ * // computation, so it is certainly better to do it only once
+ * let props4 = { flag: context["state"].flag };
+ *
+ * // If we have a component, currently rendering, but not ready yet, we do not want
+ * // to wait for it to be ready if we can avoid it
+ * if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
+ *   // we check if the props are the same.  In that case, we can simply reuse
+ *   // the previous rendering and skip all useless work
+ *   if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
+ *     def3 = w4.__owl__.renderPromise;
+ *   } else {
+ *     // if the props are not the same, we destroy the component and starts anew.
+ *     // this will be faster than waiting for its rendering, then updating it
+ *     w4.destroy();
+ *     w4 = false;
+ *   }
+ * }
+ *
+ * if (!w4) {
+ *   // in this situation, we need to create a new component.  First step is
+ *   // to get a reference to the class, then create an instance with
+ *   // current context as parent, and the props.
+ *   let W4 = context.component && context.components[componentKey4] || QWeb.component[componentKey4];
+
+ *   if (!W4) {
+ *     throw new Error("Cannot find the definition of component 'child'");
+ *   }
+ *   w4 = new W4(owner, props4);
+ *
+ *   // Whenever we rerender the parent component, we need to be sure that we
+ *   // are able to find the component instance. To do that, we register it to
+ *   // the parent cmap (children map).  Note that the 'template' key is
+ *   // used here, since this is what identify the component from the template
+ *   // perspective.
+ *   context.__owl__.cmap[key5] = w4.__owl__.id;
+ *
+ *   // __prepare is called, to basically call willStart, then render the
+ *   // component
+ *   def3 = w4.__prepare();
+ *
+ *   def3 = def3.then(vnode => {
+ *     // we create here a virtual node for the parent (NOT the component). This
+ *     // means that the vdom of the parent will be stopped here, and from
+ *     // the parent's perspective, it simply is a vnode with no children.
+ *     // However, it shares the same dom element with the component root
+ *     // vnode.
+ *     let pvnode = h(vnode.sel, { key: key5 });
+ *
+ *     // we add hooks to the parent vnode so we can interact with the new
+ *     // component at the proper time
+ *     pvnode.data.hook = {
+ *       insert(vn) {
+ *         // the __mount method will patch the component vdom into the elm vn.elm,
+ *         // then call the mounted hooks. However, suprisingly, the snabbdom
+ *         // patch method actually replace the elm by a new elm, so we need
+ *         // to synchronise the pvnode elm with the resulting elm
+ *         let nvn = w4.__mount(vnode, vn.elm);
+ *         pvnode.elm = nvn.elm;
+ *         // what follows is only present if there are animations on the component
+ *         utils.transitionInsert(vn, "fade");
+ *       },
+ *       remove() {
+ *         // override with empty function to prevent from removing the node
+ *         // directly. It will be removed when destroy is called anyway, which
+ *         // delays the removal if there are animations.
+ *       },
+ *       destroy() {
+ *         // if there are animations, we delay the call to destroy on the
+ *         // component, if not, we call it directly.
+ *         let finalize = () => {
+ *           w4.destroy();
+ *         };
+ *         utils.transitionRemove(vn, "fade", finalize);
+ *       }
+ *     };
+ *     // the pvnode is inserted at the correct position in the div's children
+ *     c1[_2_index] = pvnode;
+ *
+ *     // we keep here a reference to the parent vnode (representing the
+ *     // component, so we can reuse it later whenever we update the component
+ *     w4.__owl__.pvnode = pvnode;
+ *   });
+ * } else {
+ *   // this is the 'update' path of the directive.
+ *   // the call to __updateProps is the actual component update
+ *   // Note that we only update the props if we cannot reuse the previous
+ *   // rendering work (in the case it was rendered with the same props)
+ *   def3 = def3 || w4.__updateProps(props4, extra.forceUpdate, extra.patchQueue);
+ *   def3 = def3.then(() => {
+ *     // if component was destroyed in the meantime, we do nothing (so, this
+ *     // means that the parent's element children list will have a null in
+ *     // the component's position, which will cause the pvnode to be removed
+ *     // when it is patched.
+ *     if (w4.__owl__.isDestroyed) {
+ *       return;
+ *     }
+ *     // like above, we register the pvnode to the children list, so it
+ *     // will not be patched out of the dom.
+ *     let pvnode = w4.__owl__.pvnode;
+ *     c1[_2_index] = pvnode;
+ *   });
+ * }
+ *
+ * // we register the deferred here so the parent can coordinate its patch operation
+ * // with all the children.
+ * extra.promises.push(def3);
+ * return vn1;
+ * ```
+ */
+
+QWeb.addDirective({
+  name: "component",
+  extraNames: ["props", "keepalive", "asyncroot"],
+  priority: 100,
+  atNodeEncounter({ ctx, value, node, qweb }): boolean {
+    ctx.addLine("//COMPONENT");
+    ctx.rootContext.shouldDefineOwner = true;
+    ctx.rootContext.shouldDefineQWeb = true;
+    ctx.rootContext.shouldDefineUtils = true;
+    let keepAlive = node.getAttribute("t-keepalive") ? true : false;
+    let async = node.getAttribute("t-asyncroot") ? true : false;
+
+    // t-on- events and t-transition
+    const events: [string, string[], string, string][] = [];
+    let transition: string = "";
+    const attributes = (<Element>node).attributes;
+    const props: { [key: string]: string } = {};
+    for (let i = 0; i < attributes.length; i++) {
+      const name = attributes[i].name;
+      const value = attributes[i].textContent!;
+      if (name.startsWith("t-on-")) {
+        const [eventName, ...mods] = name.slice(5).split(".");
+        let extraArgs;
+        let handlerName = value.replace(/\(.*\)/, function(args) {
+          extraArgs = args.slice(1, -1);
+          return "";
+        });
+        events.push([eventName, mods, handlerName, extraArgs]);
+      } else if (name === "t-transition") {
+        transition = value;
+      } else if (!name.startsWith("t-")) {
+        if (name !== "class" && name !== "style") {
+          // this is a prop!
+          props[name] = ctx.formatExpression(value);
+        }
+      }
+    }
+
+    let key = node.getAttribute("t-key");
+    if (key) {
+      key = ctx.formatExpression(key);
+    }
+
+    // computing the props string representing the props object
+    let propStr = Object.keys(props)
+      .map(k => k + ":" + props[k])
+      .join(",");
+    let dummyID = ctx.generateID();
+    let defID = ctx.generateID();
+    let componentID = ctx.generateID();
+    let keyID = key && ctx.generateID();
+    if (key) {
+      // we bind a variable to the key (could be a complex expression, so we
+      // want to evaluate it only once)
+      ctx.addLine(`let key${keyID} = ${key};`);
+    }
+    ctx.addLine(`let def${defID};`);
+    let templateID = key
+      ? `key${keyID}`
+      : ctx.inLoop
+      ? `String(-${componentID} - i)`
+      : String(componentID);
+    if (ctx.allowMultipleRoots) {
+      // necessary to prevent collisions
+      if (!key && ctx.inLoop) {
+        let id = ctx.generateID();
+        ctx.addLine(`let template${id} = "_slot_" + String(-${componentID} - i)`);
+        templateID = `template${id}`;
+      } else {
+        templateID = `"_slot_${templateID}"`;
+      }
+    }
+
+    let ref = node.getAttribute("t-ref");
+    let refExpr = "";
+    let refKey: string = "";
+    if (ref) {
+      refKey = `ref${ctx.generateID()}`;
+      ctx.addLine(`const ${refKey} = ${ctx.interpolate(ref)};`);
+      refExpr = `context.refs[${refKey}] = w${componentID};`;
+    }
+    let transitionsInsertCode = "";
+    if (transition) {
+      transitionsInsertCode = `utils.transitionInsert(vn, '${transition}');`;
+    }
+    let finalizeComponentCode = `w${componentID}.${keepAlive ? "unmount" : "destroy"}();`;
+    if (ref && !keepAlive) {
+      finalizeComponentCode += `delete context.refs[${refKey}];`;
+    }
+    if (transition) {
+      finalizeComponentCode = `let finalize = () => {
+          ${finalizeComponentCode}
+        };
+        utils.transitionRemove(vn, '${transition}', finalize);`;
+    }
+
+    let createHook = "";
+    let classAttr = node.getAttribute("class");
+    let tattClass = node.getAttribute("t-att-class");
+    let styleAttr = node.getAttribute("style");
+    let tattStyle = node.getAttribute("t-att-style");
+    if (tattStyle) {
+      const attVar = `_${ctx.generateID()}`;
+      ctx.addLine(`const ${attVar} = ${ctx.formatExpression(tattStyle)};`);
+      tattStyle = attVar;
+    }
+    let classObj = "";
+    if (classAttr || tattClass || styleAttr || tattStyle || events.length) {
+      if (classAttr) {
+        let classDef = classAttr
+          .trim()
+          .split(/\s+/)
+          .map(a => `'${a}':true`)
+          .join(",");
+        classObj = `_${ctx.generateID()}`;
+        ctx.addLine(`let ${classObj} = {${classDef}};`);
+      }
+      if (tattClass) {
+        let tattExpr = ctx.formatExpression(tattClass);
+        if (tattExpr[0] !== "{" || tattExpr[tattExpr.length - 1] !== "}") {
+          tattExpr = `this.utils.toObj(${tattExpr})`;
+        }
+        if (classAttr) {
+          ctx.addLine(`Object.assign(${classObj}, ${tattExpr})`);
+        } else {
+          classObj = `_${ctx.generateID()}`;
+          ctx.addLine(`let ${classObj} = ${tattExpr};`);
+        }
+      }
+      let eventsCode = events
+        .map(function([eventName, mods, handlerName, extraArgs]) {
+          let params = "owner";
+          if (extraArgs) {
+            if (ctx.inLoop) {
+              let argId = ctx.generateID();
+              // we need to evaluate the arguments now, because the handler will
+              // be set asynchronously later when the widget is ready, and the
+              // context might be different.
+              ctx.addLine(`let arg${argId} = ${ctx.formatExpression(extraArgs)};`);
+              params = `owner, arg${argId}`;
+            } else {
+              params = `owner, ${ctx.formatExpression(extraArgs)}`;
+            }
+          }
+          let handler;
+          if (mods.length > 0) {
+            handler = `function (e) {`;
+            handler += mods
+              .map(function(mod) {
+                return T_COMPONENT_MODS_CODE[mod];
+              })
+              .join("");
+            handler += `owner['${handlerName}'].call(${params}, e);}`;
+          } else {
+            handler = `owner['${handlerName}'].bind(${params})`;
+          }
+          return `vn.elm.addEventListener('${eventName}', ${handler});`;
+        })
+        .join("");
+      const styleExpr = tattStyle || (styleAttr ? `'${styleAttr}'` : false);
+      const styleCode = styleExpr ? `vn.elm.style = ${styleExpr};` : "";
+      createHook = `vnode.data.hook = {create(_, vn){${styleCode}${eventsCode}}};`;
+    }
+
+    ctx.addLine(
+      `let w${componentID} = ${templateID} in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[${templateID}]] : false;`
+    );
+    ctx.addLine(`let _${dummyID}_index = c${ctx.parentNode}.length;`);
+    if (async) {
+      ctx.addLine(`const patchQueue${componentID} = [];`);
+      ctx.addLine(
+        `c${ctx.parentNode}.push(w${componentID} && w${componentID}.__owl__.pvnode || null);`
+      );
+    } else {
+      ctx.addLine(`c${ctx.parentNode}.push(null);`);
+    }
+    ctx.addLine(`let props${componentID} = {${propStr}};`);
+    ctx.addIf(
+      `w${componentID} && w${componentID}.__owl__.renderPromise && !w${componentID}.__owl__.vnode`
+    );
+    ctx.addIf(`utils.shallowEqual(props${componentID}, w${componentID}.__owl__.renderProps)`);
+    ctx.addLine(`def${defID} = w${componentID}.__owl__.renderPromise;`);
+    ctx.addElse();
+    ctx.addLine(`w${componentID}.destroy();`);
+    ctx.addLine(`w${componentID} = false;`);
+    ctx.closeIf();
+    ctx.closeIf();
+
+    ctx.addIf(`!w${componentID}`);
+    // new component
+    ctx.addLine(`let componentKey${componentID} = ${ctx.interpolate(value)};`);
+    ctx.addLine(
+      `let W${componentID} = context.components && context.components[componentKey${componentID}] || QWeb.components[componentKey${componentID}];`
+    );
+
+    // maybe only do this in dev mode...
+    ctx.addLine(
+      `if (!W${componentID}) {throw new Error('Cannot find the definition of component "' + componentKey${componentID} + '"')}`
+    );
+    ctx.addLine(`w${componentID} = new W${componentID}(owner, props${componentID});`);
+    ctx.addLine(`context.__owl__.cmap[${templateID}] = w${componentID}.__owl__.id;`);
+
+    // SLOTS
+    if (node.childNodes.length) {
+      const clone = <Element>node.cloneNode(true);
+      const slotNodes = clone.querySelectorAll("[t-set]");
+      const slotId = qweb.nextSlotId++;
+      ctx.addLine(`w${componentID}.__owl__.slotId = ${slotId};`);
+      if (slotNodes.length) {
+        for (let i = 0, length = slotNodes.length; i < length; i++) {
+          const slotNode = slotNodes[i];
+          slotNode.parentElement!.removeChild(slotNode);
+          const key = slotNode.getAttribute("t-set")!;
+          slotNode.removeAttribute("t-set");
+          const slotFn = qweb._compile(`slot_${key}_template`, slotNode, ctx.parentNode!);
+          qweb.slots[`${slotId}_${key}`] = slotFn.bind(qweb);
+        }
+      }
+      if (clone.childNodes.length) {
+        const t = clone.ownerDocument!.createElement("t");
+        for (let child of Object.values(clone.childNodes)) {
+          t.appendChild(child);
+        }
+        const slotFn = qweb._compile(`slot_default_template`, t, ctx.parentNode!);
+        qweb.slots[`${slotId}_default`] = slotFn.bind(qweb);
+      }
+    }
+
+    ctx.addLine(`def${defID} = w${componentID}.__prepare();`);
+    // hack: specify empty remove hook to prevent the node from being removed from the DOM
+    ctx.addLine(
+      `def${defID} = def${defID}.then(vnode=>{${createHook}let pvnode=h(vnode.sel, {key: ${templateID}, hook: {insert(vn) {let nvn=w${componentID}.__mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;${refExpr}${transitionsInsertCode}},remove() {},destroy(vn) {${finalizeComponentCode}}}});c${
+        ctx.parentNode
+      }[_${dummyID}_index]=pvnode;w${componentID}.__owl__.pvnode = pvnode;});`
+    );
+
+    ctx.addElse();
+    // need to update component
+    const patchQueueCode = async ? `patchQueue${componentID}` : "extra.patchQueue";
+    ctx.addLine(
+      `def${defID} = def${defID} || w${componentID}.__updateProps(props${componentID}, extra.forceUpdate, ${patchQueueCode});`
+    );
+    let keepAliveCode = "";
+    if (keepAlive) {
+      keepAliveCode = `pvnode.data.hook.insert = vn => {vn.elm.parentNode.replaceChild(w${componentID}.el,vn.elm);vn.elm=w${componentID}.el;w${componentID}.__remount();};`;
+    }
+    ctx.addLine(
+      `def${defID} = def${defID}.then(()=>{if (w${componentID}.__owl__.isDestroyed) {return};${
+        tattStyle ? `w${componentID}.el.style=${tattStyle};` : ""
+      }let pvnode=w${componentID}.__owl__.pvnode;${keepAliveCode}c${
+        ctx.parentNode
+      }[_${dummyID}_index]=pvnode;});`
+    );
+    ctx.closeIf();
+
+    if (classObj) {
+      ctx.addLine(`w${componentID}.__owl__.classObj=${classObj};`);
+    }
+
+    if (async) {
+      ctx.addLine(
+        `def${defID}.then(w${componentID}.__applyPatchQueue.bind(w${componentID}, patchQueue${componentID}));`
+      );
+    } else {
+      ctx.addLine(`extra.promises.push(def${defID});`);
+    }
+
+    if (node.hasAttribute("t-if") || node.hasAttribute("t-else") || node.hasAttribute("t-elif")) {
+      ctx.closeIf();
+    }
+
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-mounted
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "mounted",
+  priority: 97,
+  atNodeCreation({ ctx, fullName, value, nodeID, addNodeHook }) {
+    ctx.rootContext.shouldDefineOwner = true;
+    const eventName = fullName.slice(5);
+    if (!eventName) {
+      throw new Error("Missing event name with t-on directive");
+    }
+    let extraArgs;
+    let handler = value.replace(/\(.*\)/, function(args) {
+      extraArgs = args.slice(1, -1);
+      return "";
+    });
+    let error = `(function () {throw new Error('Missing handler \\'' + '${handler}' + \`\\' when evaluating template '${ctx.templateName.replace(
+      /`/g,
+      "'"
+    )}'\`)})()`;
+    if (extraArgs) {
+      ctx.addLine(
+        `extra.mountedHandlers[${nodeID}] = (context['${handler}'] || ${error}).bind(owner, ${ctx.formatExpression(
+          extraArgs
+        )});`
+      );
+    } else {
+      ctx.addLine(
+        `extra.mountedHandlers[${nodeID}] = extra.mountedHandlers[${nodeID}] || (context['${handler}'] || ${error}).bind(owner);`
+      );
+    }
+    addNodeHook("insert", `if (context.__owl__.isMounted) { extra.mountedHandlers[${nodeID}](); }`);
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-slot
+//------------------------------------------------------------------------------
+QWeb.addDirective({
+  name: "slot",
+  priority: 80,
+  atNodeEncounter({ ctx, value }): boolean {
+    const slotKey = ctx.generateID();
+    ctx.addLine(`const slot${slotKey} = this.slots[context.__owl__.slotId + '_' + '${value}'];`);
+    ctx.addIf(`slot${slotKey}`);
+    ctx.addLine(
+      `slot${slotKey}(context.__owl__.parent, Object.assign({}, extra, {parentNode: c${
+        ctx.parentNode
+      }}));`
+    );
+    ctx.closeIf();
+    return true;
+  }
+});
+
+//------------------------------------------------------------------------------
+// t-model
+//------------------------------------------------------------------------------
+UTILS.toNumber = function(val: string): number | string {
+  const n = parseFloat(val);
+  return isNaN(n) ? val : n;
+};
+
+QWeb.addDirective({
+  name: "model",
+  priority: 42,
+  atNodeCreation({ ctx, nodeID, value, node, fullName }) {
+    const type = node.getAttribute("type");
+    let handler;
+    let event = fullName.includes(".lazy") ? "change" : "input";
+    if (node.tagName === "select") {
+      ctx.addLine(`p${nodeID}.props = {value: context.state['${value}']};`);
+      event = "change";
+      handler = `(ev) => {context.state['${value}'] = ev.target.value}`;
+    } else if (type === "checkbox") {
+      ctx.addLine(`p${nodeID}.props = {checked: context.state['${value}']};`);
+      handler = `(ev) => {context.state['${value}'] = ev.target.checked}`;
+    } else if (type === "radio") {
+      const nodeValue = node.getAttribute("value")!;
+      ctx.addLine(`p${nodeID}.props = {checked:context.state['${value}'] === '${nodeValue}'};`);
+      handler = `(ev) => {context.state['${value}'] = ev.target.value}`;
+      event = "click";
+    } else {
+      ctx.addLine(`p${nodeID}.props = {value: context.state['${value}']};`);
+      const trimCode = fullName.includes(".trim") ? ".trim()" : "";
+      let valueCode = `ev.target.value${trimCode}`;
+      if (fullName.includes(".number")) {
+        ctx.rootContext.shouldDefineUtils = true;
+        valueCode = `utils.toNumber(${valueCode})`;
+      }
+      handler = `(ev) => {context.state['${value}'] = ${valueCode}}`;
+    }
+    ctx.addLine(
+      `extra.handlers['${event}' + ${nodeID}] = extra.handlers['${event}' + ${nodeID}] || (${handler});`
+    );
+    ctx.addLine(`p${nodeID}.on['${event}'] = extra.handlers['${event}' + ${nodeID}];`);
+  }
+});

src/store.ts

@@ -1,16 +1,36 @@
-import { Component } from "./component";
+import { Component, Env } from "./component";
 import { EventBus } from "./event_bus";
 import { Observer } from "./observer";
 
+/**
+ * Owl Store
+ *
+ * We have here:
+ * - a Store class
+ * - a connect function
+ *
+ * The Owl store is our answer to the problem of managing complex state across
+ * components. The main idea is that the store owns some state, allow external
+ * code to modify it through actions/mutations, and for each state changes,
+ * connected component will be notified, and updated if necessary.
+ *
+ * Note that this code is partly inspired by VueX and React/Redux
+ */
+
 //------------------------------------------------------------------------------
 // Store Definition
 //------------------------------------------------------------------------------
 
+type Mutation = ({ state, commit, getters }, ...payload: any) => void;
+type Action = ({ commit, state, dispatch, env, getters }, ...payload: any) => void;
+type Getter = ({ state, getters }, payload) => any;
+
 interface StoreConfig {
-  env?: any;
+  env?: Env;
   state?: any;
-  actions?: any;
-  mutations?: { [name: string]: any };
+  actions?: { [name: string]: Action };
+  getters?: { [name: string]: Getter };
+  mutations?: { [name: string]: Mutation };
 }
 
 interface StoreOption {
@@ -26,7 +46,9 @@ export class Store extends EventBus {
   debug: boolean;
   env: any;
   observer: Observer;
-  set: any;
+  getters: { [name: string]: (payload?) => any };
+  _gettersCache: { [name: string]: {} };
+  _updateId: number = 1;
 
   constructor(config: StoreConfig, options: StoreOption = {}) {
     super();
@@ -36,17 +58,34 @@ export class Store extends EventBus {
     this.mutations = config.mutations;
     this.env = config.env;
     this.observer = new Observer();
-    this.observer.notifyCB = this.trigger.bind(this, "update");
+    this.observer.notifyCB = this.__notifyComponents.bind(this);
     this.observer.allowMutations = false;
     this.observer.observe(this.state);
+    this.getters = {};
+    this._gettersCache = {};
 
     if (this.debug) {
       this.history.push({ state: this.state });
     }
-    this.set = this.observer.set.bind(this.observer);
+
+    const cTypes = ["undefined", "number", "string"];
+    for (let entry of Object.entries(config.getters || {})) {
+      const name: string = entry[0];
+      const func: (...any) => any = entry[1];
+      this.getters[name] = payload => {
+        if (this._commitLevel === 0 && cTypes.indexOf(typeof payload) >= 0) {
+          this._gettersCache[name] = this._gettersCache[name] || {};
+          this._gettersCache[name][payload] =
+            this._gettersCache[name][payload] ||
+            func({ state: this.state, getters: this.getters }, payload);
+          return this._gettersCache[name][payload];
+        }
+        return func({ state: this.state, getters: this.getters }, payload);
+      };
+    }
   }
 
-  dispatch(action, payload?: any): Promise<void> | void {
+  dispatch(action: string, ...payload: any): Promise<void> | void {
     if (!this.actions[action]) {
       throw new Error(`[Error] action ${action} is undefined`);
     }
@@ -55,9 +94,10 @@ export class Store extends EventBus {
         commit: this.commit.bind(this),
         dispatch: this.dispatch.bind(this),
         env: this.env,
-        state: this.state
+        state: this.state,
+        getters: this.getters
       },
-      payload
+      ...payload
     );
     if (result instanceof Promise) {
       return new Promise((resolve, reject) => {
@@ -67,7 +107,7 @@ export class Store extends EventBus {
     }
   }
 
-  commit(type, payload?: any) {
+  commit(type: string, ...payload: any): any {
     if (!this.mutations[type]) {
       throw new Error(`[Error] mutation ${type} is undefined`);
     }
@@ -79,9 +119,9 @@ export class Store extends EventBus {
       {
         commit: this.commit.bind(this),
         state: this.state,
-        set: this.set
+        getters: this.getters
       },
-      payload
+      ...payload
     );
 
     if (this._commitLevel === 1) {
@@ -90,13 +130,41 @@ export class Store extends EventBus {
         this.history.push({
           state: this.state,
           mutation: type,
-          payload: payload
+          payload: [...payload]
         });
       }
     }
     this._commitLevel--;
     return res;
   }
+
+  /**
+   * Instead of using trigger to emit an update event, we actually implement
+   * our own function to do that.  The reason is that we need to be smarter than
+   * a simple trigger function: we need to wait for parent components to be
+   * done before doing children components.  The reason is that if an update
+   * as an effect of destroying a children, we do not want to call the
+   * mapStoreToProps function of the child, nor rendering it.
+   *
+   * This method is not optimal if we have a bunch of asynchronous components:
+   * we wait sequentially for each component to be completed before updating the
+   * next.  However, the only things that matters is that children are updated
+   * after their parents.  So, this could be optimized by being smarter, and
+   * updating all widgets concurrently, except for parents/children.
+   */
+  async __notifyComponents() {
+    this._updateId++;
+    const current = this._updateId;
+    this._gettersCache = {};
+    const subs = this.subscriptions.update || [];
+    for (let i = 0, iLen = subs.length; i < iLen; i++) {
+      const sub = subs[i];
+      const shouldCallback = sub.owner ? sub.owner.__owl__.isMounted : true;
+      if (shouldCallback) {
+        await sub.callback.call(sub.owner, current);
+      }
+    }
+  }
 }
 
 //------------------------------------------------------------------------------
@@ -117,8 +185,24 @@ function deepRevNumber<T extends Object>(o: T): number {
   return 0;
 }
 
-export function connect(mapStateToProps, options: any = {}) {
+type Constructor<T> = new (...args: any[]) => T;
+interface EnvWithStore extends Env {
+  store: Store;
+}
+type HashFunction = (a: any, b: any) => number;
+interface StoreOptions {
+  getStore?(Env): Store;
+  hashFunction?: HashFunction;
+  deep?: boolean;
+}
+
+export function connect<E extends EnvWithStore, P, S>(
+  Comp: Constructor<Component<E, P, S>>,
+  mapStoreToProps,
+  options: StoreOptions = <StoreOptions>{}
+) {
   let hashFunction = options.hashFunction || null;
+  const getStore = options.getStore || (env => env.store);
 
   if (!hashFunction) {
     let deep = "deep" in options ? options.deep : true;
@@ -144,75 +228,96 @@ export function connect(mapStateToProps, options: any = {}) {
     };
   }
 
-  return function(Comp) {
-    return class extends Comp {
-      constructor(parent, props?: any) {
-        const env = parent instanceof Component ? parent.env : parent;
-        const ownProps = Object.assign({}, props || {});
-        const storeProps = mapStateToProps(env.store.state, ownProps);
-        const mergedProps = Object.assign({}, props || {}, storeProps);
-        super(parent, mergedProps);
-        this.__owl__.ownProps = ownProps;
-        this.__owl__.currentStoreProps = storeProps;
-        this.__owl__.storeHash = hashFunction(
-          {
-            state: env.store.state,
-            storeProps: storeProps,
-            revNumber,
-            deepRevNumber
-          },
-          {
-            currentStoreProps: storeProps
-          }
-        );
-      }
-      mounted() {
-        this.env.store.on("update", this, () => {
-          const ownProps = this.__owl__.ownProps;
-          const storeProps = mapStateToProps(this.env.store.state, ownProps);
-          const options: any = {
-            currentStoreProps: this.__owl__.currentStoreProps
-          };
-          const storeHash = hashFunction(
-            {
-              state: this.env.store.state,
-              storeProps: storeProps,
-              revNumber,
-              deepRevNumber
-            },
-            options
-          );
-          let didChange = options.didChange;
-          if (storeHash !== this.__owl__.storeHash) {
-            didChange = true;
-            this.__owl__.storeHash = storeHash;
-          }
-          if (didChange) {
-            this.__owl__.currentStoreProps = storeProps;
-            this._updateProps(ownProps, false);
-          }
-        });
-        super.mounted();
-      }
-      willUnmount() {
-        this.env.store.off("update", this);
-        super.willUnmount();
-      }
-      _updateProps(nextProps, forceUpdate) {
-        if (this.__owl__.ownProps !== nextProps) {
-          this.__owl__.currentStoreProps = mapStateToProps(
-            this.env.store.state,
-            nextProps
-          );
+  const Result = class extends Comp {
+    constructor(parent, props?: any) {
+      const env = parent instanceof Component ? parent.env : parent;
+      const store = getStore(env);
+      const ownProps = Object.assign({}, props || {});
+      const storeProps = mapStoreToProps(store.state, ownProps, store.getters);
+      const mergedProps = Object.assign({}, props || {}, storeProps);
+      super(parent, mergedProps);
+      (<any>this.__owl__).ownProps = ownProps;
+      (<any>this.__owl__).currentStoreProps = storeProps;
+      (<any>this.__owl__).store = store;
+      (<any>this.__owl__).storeHash = (<HashFunction>hashFunction)(
+        {
+          state: store.state,
+          storeProps: storeProps,
+          revNumber,
+          deepRevNumber
+        },
+        {
+          currentStoreProps: storeProps
         }
-        this.__owl__.ownProps = nextProps;
-        const mergedProps = Object.assign(
-          {},
-          nextProps,
-          this.__owl__.currentStoreProps
-        );
-        return super._updateProps(mergedProps, forceUpdate);
+      );
+    }
+    /**
+     * We do not use the mounted hook here for a subtle reason: we want the
+     * updates to be called for the parents before the children.  However,
+     * if we use the mounted hook, this will be done in the reverse order.
+     */
+    __callMounted() {
+      (<any>this.__owl__).store.on("update", this, this.__checkUpdate);
+      super.__callMounted();
+    }
+    willUnmount() {
+      (<any>this.__owl__).store.off("update", this);
+      super.willUnmount();
+    }
+
+    async __checkUpdate(updateId) {
+      if (updateId === (<any>this.__owl__).currentUpdateId) {
+        return;
       }
-    };
+      const ownProps = (<any>this.__owl__).ownProps;
+      const storeProps = mapStoreToProps(
+        (<any>this.__owl__).store.state,
+        ownProps,
+        (<any>this.__owl__).store.getters
+      );
+      const options: any = {
+        currentStoreProps: (<any>this.__owl__).currentStoreProps
+      };
+      const storeHash = (<HashFunction>hashFunction)(
+        {
+          state: (<any>this.__owl__).store.state,
+          storeProps: storeProps,
+          revNumber,
+          deepRevNumber
+        },
+        options
+      );
+      let didChange = options.didChange;
+      if (storeHash !== (<any>this.__owl__).storeHash) {
+        didChange = true;
+        (<any>this.__owl__).storeHash = storeHash;
+      }
+      if (didChange) {
+        (<any>this.__owl__).currentStoreProps = storeProps;
+        await this.__updateProps(ownProps, false);
+      }
+    }
+    __updateProps(nextProps, forceUpdate, patchQueue?: any[]) {
+      const __owl__ = <any>this.__owl__;
+      __owl__.currentUpdateId = __owl__.store._updateId;
+      if (__owl__.ownProps !== nextProps) {
+        __owl__.currentStoreProps = mapStoreToProps(
+          __owl__.store.state,
+          nextProps,
+          __owl__.store.getters
+        );
+      }
+      __owl__.ownProps = nextProps;
+      const mergedProps = Object.assign({}, nextProps, __owl__.currentStoreProps);
+      return super.__updateProps(mergedProps, forceUpdate, patchQueue);
+    }
   };
+
+  // we assign here a unique name to the resulting anonymous class.
+  // this is necessary for Owl to be able to properly deduce templates.
+  // Otherwise, all connected components would have the same name, and then
+  // each component after the first will necessarily have the same template.
+  let name = `Connected${Comp.name}`;
+  Object.defineProperty(Result, "name", { value: name });
+  return Result;
 }

src/utils.ts

@@ -1,129 +1,23 @@
-export function escape(str: string | number | undefined): string {
-  if (str === undefined) {
-    return "";
-  }
-  if (typeof str === "number") {
-    return String(str);
-  }
-  return str
-    .replace(/&/g, "&")
-    .replace(/</g, "&lt;")
-    .replace(/>/g, "&gt;")
-    .replace(/"/g, "&#x27;")
-    .replace(/`/g, "&#x60;");
-}
-
-export type HashFn = (args: any[]) => string;
-
-export function memoize<R, T extends (...args: any[]) => R>(
-  f: T,
-  hash?: HashFn
-): T {
-  if (!hash) {
-    hash = args => args.map(a => String(a)).join(",");
-  }
-  let cache: { [key: string]: R } = {};
-  function memoizedFunction(...args: any[]) {
-    let hashValue = hash!(args);
-    if (!(hashValue in cache)) {
-      cache[hashValue] = f(...args);
-    }
-    return cache[hashValue];
-  }
-  return memoizedFunction as T;
-}
-
 /**
- * Returns a function, that, as long as it continues to be invoked, will not
- * be triggered. The function will be called after it stops being called for
- * N milliseconds. If `immediate` is passed, trigger the function on the
- * leading edge, instead of the trailing.
+ * Owl Utils
  *
- * Inspired by https://davidwalsh.name/javascript-debounce-function
+ * We have here a small collection of utility functions:
+ *
+ * - whenReady
+ * - loadJS
+ * - loadTemplates
+ * - escape
+ * - debounce
  */
-export function debounce(
-  func: Function,
-  wait: number,
-  immediate?: boolean
-): Function {
-  let timeout;
-  return function(this: any) {
-    const context = this;
-    const args = arguments;
-    function later() {
-      timeout = null;
-      if (!immediate) {
-        func.apply(context, args);
-      }
+
+export function whenReady(fn) {
+  return new Promise(function(resolve) {
+    if (document.readyState !== "loading") {
+      resolve();
+    } else {
+      document.addEventListener("DOMContentLoaded", resolve, false);
     }
-    const callNow = immediate && !timeout;
-    clearTimeout(timeout);
-    timeout = setTimeout(later, wait);
-    if (callNow) {
-      func.apply(context, args);
-    }
-  };
-}
-
-export function patch(C: any, patchName: string, patch: any) {
-  const proto = C.prototype;
-  if (!proto.__patches) {
-    proto.__patches = {
-      origMethods: {},
-      patches: {},
-      current: []
-    };
-  }
-  if (proto.__patches.patches[patchName]) {
-    throw new Error(`Patch [${patchName}] already exists`);
-  }
-  proto.__patches.patches[patchName] = patch;
-  applyPatch(proto, patch);
-  proto.__patches.current.push(patchName);
-
-  function applyPatch(proto, patch) {
-    Object.keys(patch).forEach(function(methodName) {
-      const method = patch[methodName];
-      if (typeof method === "function") {
-        const original = proto[methodName];
-        if (!(methodName in proto.__patches.origMethods)) {
-          proto.__patches.origMethods[methodName] = original;
-        }
-        proto[methodName] = function(...args) {
-          this._super = original;
-          return method.call(this, ...args);
-        };
-      }
-    });
-  }
-}
-
-export function unpatch(C: any, patchName: string) {
-  const proto = C.prototype;
-  const patchInfo = proto.__patches;
-  delete proto.__patches;
-
-  // reset to original
-  for (let k in patchInfo.origMethods) {
-    proto[k] = patchInfo.origMethods[k];
-  }
-
-  // apply other patches
-  for (let name of patchInfo.current) {
-    if (name !== patchName) {
-      patch(C, name, patchInfo.patches[name]);
-    }
-  }
-}
-
-export async function loadTemplates(url: string): Promise<string> {
-  const result = await fetch(url);
-  if (!result.ok) {
-    throw new Error("Error while fetching xml templates");
-  }
-  let templates = await result.text();
-  templates = templates.replace(/<!--[\s\S]*?-->/g, "");
-  return templates;
+  }).then(fn || function() {});
 }
 
 const loadedScripts: { [key: string]: Promise<void> } = {};
@@ -149,10 +43,55 @@ export function loadJS(url: string): Promise<void> {
   return promise;
 }
 
-export function whenReady(fn) {
-  if (document.readyState === "complete") {
-    fn();
-  } else {
-    document.addEventListener("DOMContentLoaded", fn, false);
+export async function loadTemplates(url: string): Promise<string> {
+  const result = await fetch(url);
+  if (!result.ok) {
+    throw new Error("Error while fetching xml templates");
   }
+  let templates = await result.text();
+  templates = templates.replace(/<!--[\s\S]*?-->/g, "");
+  return templates;
+}
+
+export function escape(str: string | number | undefined): string {
+  if (str === undefined) {
+    return "";
+  }
+  if (typeof str === "number") {
+    return String(str);
+  }
+  return str
+    .replace(/&/g, "&amp;")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/"/g, "&#x27;")
+    .replace(/`/g, "&#x60;");
+}
+
+/**
+ * Returns a function, that, as long as it continues to be invoked, will not
+ * be triggered. The function will be called after it stops being called for
+ * N milliseconds. If `immediate` is passed, trigger the function on the
+ * leading edge, instead of the trailing.
+ *
+ * Inspired by https://davidwalsh.name/javascript-debounce-function
+ */
+export function debounce(func: Function, wait: number, immediate?: boolean): Function {
+  let timeout;
+  return function(this: any) {
+    const context = this;
+    const args = arguments;
+    function later() {
+      timeout = null;
+      if (!immediate) {
+        func.apply(context, args);
+      }
+    }
+    const callNow = immediate && !timeout;
+    clearTimeout(timeout);
+    timeout = setTimeout(later, wait);
+    if (callNow) {
+      func.apply(context, args);
+    }
+  };
 }

src/vdom.ts

@@ -1,9 +1,29 @@
+/**
+ * Owl VDOM
+ *
+ * This file contains an implementation of a virtual DOM, which is a system that
+ * can generate in-memory representations of a DOM tree, compare them, and
+ * eventually change a concrete DOM tree to match its representation, in an
+ * hopefully efficient way.
+ *
+ * Note that this code is a fork of Snabbdom, slightly tweaked/optimized for our
+ * needs (see https://github.com/snabbdom/snabbdom).
+ *
+ * The main exported values are:
+ * - interface VNode
+ * - h function (a helper function to generate a vnode)
+ * - patch function (to apply a vnode to an actual DOM node)
+ */
 
 // because those in TypeScript are too restrictive: https://github.com/Microsoft/TSJS-lib-generator/pull/237
 declare global {
   interface Element {
     setAttribute(name: string, value: string | number | boolean): void;
-    setAttributeNS(namespaceURI: string, qualifiedName: string, value: string | number | boolean): void;
+    setAttributeNS(
+      namespaceURI: string,
+      qualifiedName: string,
+      value: string | number | boolean
+    ): void;
   }
 }
 
@@ -39,14 +59,7 @@ function vnode(
   elm: Element | Text | undefined
 ): VNode {
   let key = data === undefined ? undefined : data.key;
-  return {
-    sel: sel,
-    data: data,
-    children: children,
-    text: text,
-    elm: elm,
-    key: key
-  };
+  return { sel, data, children, text, elm, key };
 }
 
 //------------------------------------------------------------------------------
@@ -96,14 +109,7 @@ function createKeyToOldIdx(
   return map;
 }
 
-const hooks: (keyof Module)[] = [
-  "create",
-  "update",
-  "remove",
-  "destroy",
-  "pre",
-  "post"
-];
+const hooks: (keyof Module)[] = ["create", "update", "remove", "destroy", "pre", "post"];
 
 export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   let i: number,
@@ -125,13 +131,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   function emptyNodeAt(elm: Element) {
     const id = elm.id ? "#" + elm.id : "";
     const c = elm.className ? "." + elm.className.split(" ").join(".") : "";
-    return vnode(
-      api.tagName(elm).toLowerCase() + id + c,
-      {},
-      [],
-      undefined,
-      elm
-    );
+    return vnode(api.tagName(elm).toLowerCase() + id + c, {}, [], undefined, elm);
   }
 
   function createRmCb(childElm: Node, listeners: number) {
@@ -145,6 +145,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
 
   function createElm(vnode: VNode, insertedVnodeQueue: VNodeQueue): Node {
     let i: any,
+      iLen: number,
       data = vnode.data;
     if (data !== undefined) {
       if (isDef((i = data.hook)) && isDef((i = i.init))) {
@@ -165,20 +166,16 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       const dotIdx = sel.indexOf(".", hashIdx);
       const hash = hashIdx > 0 ? hashIdx : sel.length;
       const dot = dotIdx > 0 ? dotIdx : sel.length;
-      const tag =
-        hashIdx !== -1 || dotIdx !== -1
-          ? sel.slice(0, Math.min(hash, dot))
-          : sel;
+      const tag = hashIdx !== -1 || dotIdx !== -1 ? sel.slice(0, Math.min(hash, dot)) : sel;
       const elm = (vnode.elm =
         isDef(data) && isDef((i = (data as VNodeData).ns))
           ? api.createElementNS(i, tag)
           : api.createElement(tag));
       if (hash < dot) elm.setAttribute("id", sel.slice(hash + 1, dot));
-      if (dotIdx > 0)
-        elm.setAttribute("class", sel.slice(dot + 1).replace(/\./g, " "));
-      for (i = 0; i < cbs.create.length; ++i) cbs.create[i](emptyNode, vnode);
+      if (dotIdx > 0) elm.setAttribute("class", sel.slice(dot + 1).replace(/\./g, " "));
+      for (i = 0, iLen = cbs.create.length; i < iLen; ++i) cbs.create[i](emptyNode, vnode);
       if (array(children)) {
-        for (i = 0; i < children.length; ++i) {
+        for (i = 0, iLen = children.length; i < iLen; ++i) {
           const ch = children[i];
           if (ch != null) {
             api.appendChild(elm, createElm(ch as VNode, insertedVnodeQueue));
@@ -216,13 +213,15 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
 
   function invokeDestroyHook(vnode: VNode) {
     let i: any,
+      iLen: number,
       j: number,
+      jLen: number,
       data = vnode.data;
     if (data !== undefined) {
       if (isDef((i = data.hook)) && isDef((i = i.destroy))) i(vnode);
-      for (i = 0; i < cbs.destroy.length; ++i) cbs.destroy[i](vnode);
+      for (i = 0, iLen = cbs.destroy.length; i < iLen; ++i) cbs.destroy[i](vnode);
       if (vnode.children !== undefined) {
-        for (j = 0; j < vnode.children.length; ++j) {
+        for (j = 0, jLen = vnode.children.length; j < jLen; ++j) {
           i = vnode.children[j];
           if (i != null && typeof i !== "string") {
             invokeDestroyHook(i);
@@ -240,6 +239,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   ): void {
     for (; startIdx <= endIdx; ++startIdx) {
       let i: any,
+        iLen: number,
         listeners: number,
         rm: () => void,
         ch = vnodes[startIdx];
@@ -248,12 +248,8 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           invokeDestroyHook(ch);
           listeners = cbs.remove.length + 1;
           rm = createRmCb(ch.elm as Node, listeners);
-          for (i = 0; i < cbs.remove.length; ++i) cbs.remove[i](ch, rm);
-          if (
-            isDef((i = ch.data)) &&
-            isDef((i = i.hook)) &&
-            isDef((i = i.remove))
-          ) {
+          for (i = 0, iLen = cbs.remove.length; i < iLen; ++i) cbs.remove[i](ch, rm);
+          if (isDef((i = ch.data)) && isDef((i = i.hook)) && isDef((i = i.remove))) {
             i(ch, rm);
           } else {
             rm();
@@ -315,11 +311,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       } else if (sameVnode(oldEndVnode, newStartVnode)) {
         // Vnode moved left
         patchVnode(oldEndVnode, newStartVnode, insertedVnodeQueue);
-        api.insertBefore(
-          parentElm,
-          oldEndVnode.elm as Node,
-          oldStartVnode.elm as Node
-        );
+        api.insertBefore(parentElm, oldEndVnode.elm as Node, oldStartVnode.elm as Node);
         oldEndVnode = oldCh[--oldEndIdx];
         newStartVnode = newCh[++newStartIdx];
       } else {
@@ -346,11 +338,7 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           } else {
             patchVnode(elmToMove, newStartVnode, insertedVnodeQueue);
             oldCh[idxInOld] = undefined as any;
-            api.insertBefore(
-              parentElm,
-              elmToMove.elm as Node,
-              oldStartVnode.elm as Node
-            );
+            api.insertBefore(parentElm, elmToMove.elm as Node, oldStartVnode.elm as Node);
           }
           newStartVnode = newCh[++newStartIdx];
         }
@@ -359,31 +347,16 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
     if (oldStartIdx <= oldEndIdx || newStartIdx <= newEndIdx) {
       if (oldStartIdx > oldEndIdx) {
         before = newCh[newEndIdx + 1] == null ? null : newCh[newEndIdx + 1].elm;
-        addVnodes(
-          parentElm,
-          before,
-          newCh,
-          newStartIdx,
-          newEndIdx,
-          insertedVnodeQueue
-        );
+        addVnodes(parentElm, before, newCh, newStartIdx, newEndIdx, insertedVnodeQueue);
       } else {
         removeVnodes(parentElm, oldCh, oldStartIdx, oldEndIdx);
       }
     }
   }
 
-  function patchVnode(
-    oldVnode: VNode,
-    vnode: VNode,
-    insertedVnodeQueue: VNodeQueue
-  ) {
-    let i: any, hook: any;
-    if (
-      isDef((i = vnode.data)) &&
-      isDef((hook = i.hook)) &&
-      isDef((i = hook.prepatch))
-    ) {
+  function patchVnode(oldVnode: VNode, vnode: VNode, insertedVnodeQueue: VNodeQueue) {
+    let i: any, iLen: number, hook: any;
+    if (isDef((i = vnode.data)) && isDef((hook = i.hook)) && isDef((i = hook.prepatch))) {
       i(oldVnode, vnode);
     }
     const elm = (vnode.elm = oldVnode.elm as Node);
@@ -391,19 +364,14 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
     let ch = vnode.children;
     if (oldVnode === vnode) return;
     if (vnode.data !== undefined) {
-      for (i = 0; i < cbs.update.length; ++i) cbs.update[i](oldVnode, vnode);
+      for (i = 0, iLen = cbs.update.length; i < iLen; ++i) cbs.update[i](oldVnode, vnode);
       i = vnode.data.hook;
       if (isDef(i) && isDef((i = i.update))) i(oldVnode, vnode);
     }
     if (isUndef(vnode.text)) {
       if (isDef(oldCh) && isDef(ch)) {
         if (oldCh !== ch)
-          updateChildren(
-            elm,
-            oldCh as Array<VNode>,
-            ch as Array<VNode>,
-            insertedVnodeQueue
-          );
+          updateChildren(elm, oldCh as Array<VNode>, ch as Array<VNode>, insertedVnodeQueue);
       } else if (isDef(ch)) {
         if (isDef(oldVnode.text)) api.setTextContent(elm, "");
         addVnodes(
@@ -415,23 +383,13 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
           insertedVnodeQueue
         );
       } else if (isDef(oldCh)) {
-        removeVnodes(
-          elm,
-          oldCh as Array<VNode>,
-          0,
-          (oldCh as Array<VNode>).length - 1
-        );
+        removeVnodes(elm, oldCh as Array<VNode>, 0, (oldCh as Array<VNode>).length - 1);
       } else if (isDef(oldVnode.text)) {
         api.setTextContent(elm, "");
       }
     } else if (oldVnode.text !== vnode.text) {
       if (isDef(oldCh)) {
-        removeVnodes(
-          elm,
-          oldCh as Array<VNode>,
-          0,
-          (oldCh as Array<VNode>).length - 1
-        );
+        removeVnodes(elm, oldCh as Array<VNode>, 0, (oldCh as Array<VNode>).length - 1);
       }
       api.setTextContent(elm, vnode.text as string);
     }
@@ -441,9 +399,9 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
   }
 
   return function patch(oldVnode: VNode | Element, vnode: VNode): VNode {
-    let i: number, elm: Node, parent: Node;
+    let i: number, iLen: number, elm: Node, parent: Node;
     const insertedVnodeQueue: VNodeQueue = [];
-    for (i = 0; i < cbs.pre.length; ++i) cbs.pre[i]();
+    for (i = 0, iLen = cbs.pre.length; i < iLen; ++i) cbs.pre[i]();
 
     if (!isVnode(oldVnode)) {
       oldVnode = emptyNodeAt(oldVnode);
@@ -463,12 +421,12 @@ export function init(modules: Array<Partial<Module>>, domApi?: DOMAPI) {
       }
     }
 
-    for (i = 0; i < insertedVnodeQueue.length; ++i) {
+    for (i = 0, iLen = insertedVnodeQueue.length; i < iLen; ++i) {
       (((insertedVnodeQueue[i].data as VNodeData).hook as Hooks).insert as any)(
         insertedVnodeQueue[i]
       );
     }
-    for (i = 0; i < cbs.post.length; ++i) cbs.post[i]();
+    for (i = 0, iLen = cbs.post.length; i < iLen; ++i) cbs.post[i]();
     return vnode;
   };
 }
@@ -489,11 +447,7 @@ interface DOMAPI {
   createElementNS: (namespaceURI: string, qualifiedName: string) => Element;
   createTextNode: (text: string) => Text;
   createComment: (text: string) => Comment;
-  insertBefore: (
-    parentNode: Node,
-    newNode: Node,
-    referenceNode: Node | null
-  ) => void;
+  insertBefore: (parentNode: Node, newNode: Node, referenceNode: Node | null) => void;
   removeChild: (node: Node, child: Node) => void;
   appendChild: (node: Node, child: Node) => void;
   parentNode: (node: Node) => Node;
@@ -522,11 +476,7 @@ function createComment(text: string): Comment {
   return document.createComment(text);
 }
 
-function insertBefore(
-  parentNode: Node,
-  newNode: Node,
-  referenceNode: Node | null
-): void {
+function insertBefore(parentNode: Node, newNode: Node, referenceNode: Node | null): void {
   parentNode.insertBefore(newNode, referenceNode);
 }
 
@@ -623,21 +573,13 @@ type VNodeChildElement = VNode | string | number | undefined | null;
 type ArrayOrElement<T> = T | T[];
 type VNodeChildren = ArrayOrElement<VNodeChildElement>;
 
-function addNS(
-  data: any,
-  children: VNodes | undefined,
-  sel: string | undefined
-): void {
+function addNS(data: any, children: VNodes | undefined, sel: string | undefined): void {
   data.ns = "http://www.w3.org/2000/svg";
   if (sel !== "foreignObject" && children !== undefined) {
-    for (let i = 0; i < children.length; ++i) {
+    for (let i = 0, iLen = children.length; i < iLen; ++i) {
       let childData = children[i].data;
       if (childData !== undefined) {
-        addNS(
-          childData,
-          (children[i] as VNode).children as VNodes,
-          children[i].sel
-        );
+        addNS(childData, (children[i] as VNode).children as VNodes, children[i].sel);
       }
     }
   }
@@ -651,7 +593,8 @@ export function h(sel: any, b?: any, c?: any): VNode {
   var data: VNodeData = {},
     children: any,
     text: any,
-    i: number;
+    i: number,
+    iLen: number;
   if (c !== undefined) {
     data = b;
     if (array(c)) {
@@ -673,15 +616,9 @@ export function h(sel: any, b?: any, c?: any): VNode {
     }
   }
   if (children !== undefined) {
-    for (i = 0; i < children.length; ++i) {
+    for (i = 0, iLen = children.length; i < iLen; ++i) {
       if (primitive(children[i]))
-        children[i] = vnode(
-          undefined,
-          undefined,
-          undefined,
-          children[i],
-          undefined
-        );
+        children[i] = vnode(undefined, undefined, undefined, children[i], undefined);
     }
   }
   if (
@@ -747,9 +684,7 @@ interface Module {
 //------------------------------------------------------------------------------
 // module/eventlisteners.ts
 //------------------------------------------------------------------------------
-type On = {
-  [N in keyof HTMLElementEventMap]?: (ev: HTMLElementEventMap[N]) => void
-} & {
+type On = { [N in keyof HTMLElementEventMap]?: (ev: HTMLElementEventMap[N]) => void } & {
   [event: string]: EventListener;
 };
 
@@ -771,7 +706,7 @@ function invokeHandler(handler: any, vnode?: VNode, event?: Event): void {
       }
     } else {
       // call multiple handlers
-      for (var i = 0; i < handler.length; i++) {
+      for (let i = 0, iLen = handler.length; i < iLen; i++) {
         invokeHandler(handler[i], vnode, event);
       }
     }
@@ -828,8 +763,7 @@ function updateEventListeners(oldVnode: VNode, vnode?: VNode): void {
   // add new listeners which has not already attached
   if (on) {
     // reuse existing listener or create new
-    var listener = ((vnode as any).listener =
-      (oldVnode as any).listener || createListener());
+    var listener = ((vnode as any).listener = (oldVnode as any).listener || createListener());
     // update vnode for listener
     listener.vnode = vnode;
 
@@ -916,4 +850,39 @@ export const attrsModule = {
   update: updateAttrs
 } as Module;
 
-export const patch = init([eventListenersModule, attrsModule, propsModule]);
+//------------------------------------------------------------------------------
+// class.ts
+//------------------------------------------------------------------------------
+function updateClass(oldVnode: VNode, vnode: VNode): void {
+  var cur: any,
+    name: string,
+    elm: Element,
+    oldClass = (oldVnode.data as VNodeData).class,
+    klass = (vnode.data as VNodeData).class;
+
+  if (!oldClass && !klass) return;
+  if (oldClass === klass) return;
+  oldClass = oldClass || {};
+  klass = klass || {};
+
+  elm = vnode.elm as Element;
+
+  for (name in oldClass) {
+    if (!klass[name]) {
+      elm.classList.remove(name);
+    }
+  }
+  for (name in klass) {
+    cur = klass[name];
+    if (cur !== oldClass[name]) {
+      (elm.classList as any)[cur ? "add" : "remove"](name);
+    }
+  }
+}
+
+const classModule = { create: updateClass, update: updateClass } as Module;
+
+//------------------------------------------------------------------------------
+// patch
+//------------------------------------------------------------------------------
+export const patch = init([eventListenersModule, attrsModule, propsModule, classModule]);

tests/__snapshots__/animations.test.ts.snap

@@ -0,0 +1,127 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`animations t-transition combined with component 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.utils;
+    let QWeb = this.constructor;
+    let owner = context;
+    var h = this.utils.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('div', p1, c1);
+    //COMPONENT
+    let def3;
+    let w4 = 4 in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[4]] : false;
+    let _2_index = c1.length;
+    c1.push(null);
+    let props4 = {};
+    if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
+        if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
+            def3 = w4.__owl__.renderPromise;
+        } else {
+            w4.destroy();
+            w4 = false;
+        }
+    }
+    if (!w4) {
+        let componentKey4 = \`Child\`;
+        let W4 = context.components && context.components[componentKey4] || QWeb.components[componentKey4];
+        if (!W4) {throw new Error('Cannot find the definition of component \\"' + componentKey4 + '\\"')}
+        w4 = new W4(owner, props4);
+        context.__owl__.cmap[4] = w4.__owl__.id;
+        def3 = w4.__prepare();
+        def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4, hook: {insert(vn) {let nvn=w4.__mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
+          w4.destroy();
+        };
+        utils.transitionRemove(vn, 'chimay', finalize);}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
+    } else {
+        def3 = def3 || w4.__updateProps(props4, extra.forceUpdate, extra.patchQueue);
+        def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
+    }
+    extra.promises.push(def3);
+    return vn1;
+}"
+`;
+
+exports[`animations t-transition combined with t-component and t-if 1`] = `
+"function anonymous(context,extra
+) {
+    let utils = this.utils;
+    let QWeb = this.constructor;
+    let owner = context;
+    var h = this.utils.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('div', p1, c1);
+    if (context['state'].display) {
+        //COMPONENT
+        let def3;
+        let w4 = 4 in context.__owl__.cmap ? context.__owl__.children[context.__owl__.cmap[4]] : false;
+        let _2_index = c1.length;
+        c1.push(null);
+        let props4 = {};
+        if (w4 && w4.__owl__.renderPromise && !w4.__owl__.vnode) {
+            if (utils.shallowEqual(props4, w4.__owl__.renderProps)) {
+                def3 = w4.__owl__.renderPromise;
+            } else {
+                w4.destroy();
+                w4 = false;
+            }
+        }
+        if (!w4) {
+            let componentKey4 = \`Child\`;
+            let W4 = context.components && context.components[componentKey4] || QWeb.components[componentKey4];
+            if (!W4) {throw new Error('Cannot find the definition of component \\"' + componentKey4 + '\\"')}
+            w4 = new W4(owner, props4);
+            context.__owl__.cmap[4] = w4.__owl__.id;
+            def3 = w4.__prepare();
+            def3 = def3.then(vnode=>{let pvnode=h(vnode.sel, {key: 4, hook: {insert(vn) {let nvn=w4.__mount(vnode, pvnode.elm);pvnode.elm=nvn.elm;utils.transitionInsert(vn, 'chimay');},remove() {},destroy(vn) {let finalize = () => {
+          w4.destroy();
+        };
+        utils.transitionRemove(vn, 'chimay', finalize);}}});c1[_2_index]=pvnode;w4.__owl__.pvnode = pvnode;});
+        } else {
+            def3 = def3 || w4.__updateProps(props4, extra.forceUpdate, extra.patchQueue);
+            def3 = def3.then(()=>{if (w4.__owl__.isDestroyed) {return};let pvnode=w4.__owl__.pvnode;c1[_2_index]=pvnode;});
+        }
+        extra.promises.push(def3);
+    }
+    return vn1;
+}"
+`;
+
+exports[`animations t-transition with no delay/duration 1`] = `
+"function anonymous(context,extra
+) {
+    var h = this.utils.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('span', p1, c1);
+    p1.hook = {
+      insert: vn => {
+        this.utils.transitionInsert(vn, 'jupiler');
+      },
+      remove: (vn, rm) => {
+        this.utils.transitionRemove(vn, 'jupiler', rm);
+      },
+    };
+    c1.push({text: \`blue\`});
+    return vn1;
+}"
+`;
+
+exports[`animations t-transition, on a simple node (insert) 1`] = `
+"function anonymous(context,extra
+) {
+    var h = this.utils.h;
+    let c1 = [], p1 = {key:1};
+    var vn1 = h('span', p1, c1);
+    p1.hook = {
+      insert: vn => {
+        this.utils.transitionInsert(vn, 'chimay');
+      },
+      remove: (vn, rm) => {
+        this.utils.transitionRemove(vn, 'chimay', rm);
+      },
+    };
+    c1.push({text: \`blue\`});
+    return vn1;
+}"
+`;

tests/__snapshots__/store.test.ts.snap

@@ -1,5 +1,9 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`connecting a component to store connecting a component to a local store 1`] = `"<div></div>"`;
+
+exports[`connecting a component to store connecting a component to a local store 2`] = `"<div><span>hello</span></div>"`;
+
 exports[`connecting a component to store connecting a component works 1`] = `"<div></div>"`;
 
 exports[`connecting a component to store connecting a component works 2`] = `"<div><span>hello</span></div>"`;

tests/animations.test.ts

@@ -0,0 +1,404 @@
+import { Component, Env } from "../src/component";
+import { QWeb } from "../src/qweb_core";
+import {
+  makeDeferred,
+  makeTestFixture,
+  makeTestEnv,
+  nextTick,
+  patchNextFrame,
+  renderToDOM,
+  unpatchNextFrame
+} from "./helpers";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+// We create before each test:
+// - fixture: a div, appended to the DOM, intended to be the target of dom
+//   manipulations.  Note that it is removed after each test.
+// - qweb: a new QWeb instance
+// - env: a WEnv, necessary to create new components
+// - cssEl: a stylesheet injected into the dom
+
+let fixture: HTMLElement;
+let qweb: QWeb;
+let env: Env;
+let cssEl: HTMLElement;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+  env = makeTestEnv();
+  qweb = new QWeb();
+});
+
+afterEach(() => {
+  fixture.remove();
+});
+
+class Widget extends Component<any, any, any> {}
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+describe("animations", () => {
+  beforeEach(() => {
+    cssEl = document.createElement("style");
+    let css = `
+      .chimay-enter-active, .chimay-leave-active {
+        transition-property: opacity;
+        transition-duration: 0.1s;
+      }
+      .chimay-enter, .chimay-leave-to {
+        opacity: 0;
+      }
+    `;
+    cssEl.textContent = css.trim();
+    document.head.appendChild(cssEl);
+  });
+
+  afterEach(() => {
+    document.head.removeChild(cssEl);
+    unpatchNextFrame();
+  });
+
+  test("t-transition, on a simple node (insert)", async () => {
+    expect.assertions(5);
+    qweb.addTemplate("test", `<span t-transition="chimay">blue</span>`);
+
+    let def = makeDeferred();
+    patchNextFrame(cb => {
+      expect(node.className).toBe("chimay-enter chimay-enter-active");
+      cb();
+      expect(node.className).toBe("chimay-enter-active chimay-enter-to");
+      def.resolve();
+    });
+    let node: HTMLElement = <HTMLElement>renderToDOM(qweb, "test");
+
+    expect(node.className).toBe("chimay-enter chimay-enter-active");
+    await def; // wait for the mocked repaint to be done
+    node.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(node.className).toBe("");
+  });
+
+  test("t-transition with no delay/duration", async () => {
+    expect.assertions(4);
+    qweb.addTemplate("test", `<span t-transition="jupiler">blue</span>`);
+
+    let def = makeDeferred();
+    patchNextFrame(cb => {
+      expect(node.className).toBe("jupiler-enter jupiler-enter-active");
+      cb();
+      expect(node.className).toBe("");
+      def.resolve();
+    });
+    let node: HTMLElement = <HTMLElement>renderToDOM(qweb, "test");
+    expect(node.className).toBe("jupiler-enter jupiler-enter-active");
+    await def;
+  });
+
+  test("t-transition on a conditional node", async () => {
+    expect.assertions(7);
+
+    env.qweb.addTemplate(
+      "TestWidget",
+      `<div><span t-if="!state.hide" t-transition="chimay">blue</span></div>`
+    );
+    class TestWidget extends Widget {
+      state = { hide: false };
+    }
+    const widget = new TestWidget(env);
+
+    // insert widget into the DOM
+    let def = makeDeferred();
+    var spanNode;
+    patchNextFrame(cb => {
+      expect(spanNode.className).toBe("chimay-enter chimay-enter-active");
+      cb();
+      expect(spanNode.className).toBe("chimay-enter-active chimay-enter-to");
+      def.resolve();
+    });
+    await widget.mount(fixture);
+    spanNode = widget.el!.children[0];
+    expect(spanNode.className).toBe("chimay-enter chimay-enter-active");
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(spanNode.className).toBe("");
+
+    // remove span from the DOM
+    def = makeDeferred();
+    widget.state.hide = true;
+    patchNextFrame(cb => {
+      expect(spanNode.className).toBe("chimay-leave chimay-leave-active");
+      cb();
+      expect(spanNode.className).toBe("chimay-leave-active chimay-leave-to");
+      def.resolve();
+    });
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(spanNode.className).toBe("");
+  });
+
+  test("t-transition combined with t-ref", async () => {
+    expect.assertions(5);
+
+    env.qweb.addTemplate(
+      "TestWidget",
+      `<div><span t-ref="span" t-transition="chimay">blue</span></div>`
+    );
+    class TestWidget extends Widget {
+      state = { hide: false };
+    }
+    const widget = new TestWidget(env);
+
+    // insert widget into the DOM
+    let def = makeDeferred();
+    var spanNode;
+    patchNextFrame(cb => {
+      expect(spanNode.className).toBe("chimay-enter chimay-enter-active");
+      cb();
+      expect(spanNode.className).toBe("chimay-enter-active chimay-enter-to");
+      def.resolve();
+    });
+    await widget.mount(fixture);
+    spanNode = widget.el!.children[0];
+    expect(widget.refs.span).toBe(spanNode);
+    expect(spanNode.className).toBe("chimay-enter chimay-enter-active");
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(spanNode.className).toBe("");
+  });
+
+  test("t-transition combined with component", async () => {
+    expect.assertions(5);
+
+    env.qweb.addTemplate("Parent", `<div><Child t-transition="chimay"/></div>`);
+    env.qweb.addTemplate("Child", `<span>blue</span>`);
+    class Parent extends Widget {
+      components = { Child: Child };
+    }
+    class Child extends Widget {}
+    const widget = new Parent(env);
+
+    let def = makeDeferred();
+    var spanNode;
+    patchNextFrame(cb => {
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-enter chimay-enter-active">blue</span></div>'
+      );
+      cb();
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-enter-active chimay-enter-to">blue</span></div>'
+      );
+      def.resolve();
+    });
+    await widget.mount(fixture);
+    spanNode = widget.el!.children[0];
+
+    expect(env.qweb.templates.Parent.fn.toString()).toMatchSnapshot();
+    expect(fixture.innerHTML).toBe(
+      '<div><span class="chimay-enter chimay-enter-active">blue</span></div>'
+    );
+
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><span class="">blue</span></div>');
+  });
+
+  test("t-transition combined with t-component and t-if", async () => {
+    expect.assertions(8);
+
+    env.qweb.addTemplate(
+      "Parent",
+      `<div><t t-if="state.display" t-component="Child" t-transition="chimay"/></div>`
+    );
+    env.qweb.addTemplate("Child", `<span>blue</span>`);
+    class Parent extends Widget {
+      components = { Child: Child };
+      state = { display: true };
+    }
+    class Child extends Widget {}
+    const widget = new Parent(env);
+
+    let def = makeDeferred();
+    var spanNode;
+    patchNextFrame(cb => {
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-enter chimay-enter-active">blue</span></div>'
+      );
+      cb();
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-enter-active chimay-enter-to">blue</span></div>'
+      );
+      def.resolve();
+    });
+    await widget.mount(fixture);
+    spanNode = widget.el!.children[0];
+
+    expect(env.qweb.templates.Parent.fn.toString()).toMatchSnapshot();
+    expect(fixture.innerHTML).toBe(
+      '<div><span class="chimay-enter chimay-enter-active">blue</span></div>'
+    );
+
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><span class="">blue</span></div>');
+
+    // remove span from the DOM
+    def = makeDeferred();
+    widget.state.display = false;
+    patchNextFrame(cb => {
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-leave chimay-leave-active" data-owl-key="4">blue</span></div>'
+      );
+      cb();
+      expect(fixture.innerHTML).toBe(
+        '<div><span class="chimay-leave-active chimay-leave-to" data-owl-key="4">blue</span></div>'
+      );
+      def.resolve();
+    });
+    await def; // wait for the mocked repaint to be done
+    spanNode.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe("<div></div>");
+  });
+
+  test("t-transition combined with t-mounted", async () => {
+    env.qweb.addTemplate(
+      "TestWidget",
+      `<div><span t-if="state.flag" t-mounted="f" t-transition="chimay">blue</span></div>`
+    );
+    class TestWidget extends Widget {
+      state = { flag: false };
+      f() {}
+    }
+    const widget = new TestWidget(env);
+    widget.f = jest.fn();
+    await widget.mount(fixture);
+
+    patchNextFrame(cb => cb());
+    expect(widget.f).toHaveBeenCalledTimes(0);
+
+    widget.state.flag = true;
+    await nextTick();
+    expect(widget.f).toHaveBeenCalledTimes(1);
+    unpatchNextFrame();
+  });
+
+  test("t-transition, remove and re-add before transitionend", async () => {
+    expect.assertions(11);
+
+    env.qweb.addTemplates(
+      `<templates>
+        <div t-name="Parent">
+          <button t-on-click="toggle">Toggle</button>
+          <span t-if="state.flag" t-transition="chimay">blue</span>
+        </div>
+      </templates>`
+    );
+    class Parent extends Widget {
+      constructor(parent) {
+        super(parent);
+        this.state = { flag: false };
+      }
+      toggle() {
+        this.state.flag = !this.state.flag;
+      }
+    }
+
+    const widget = new Parent(env);
+    await widget.mount(fixture);
+    let button = widget.el!.querySelector("button");
+
+    let def = makeDeferred();
+    let phase = "enter";
+    patchNextFrame(cb => {
+      let spans = fixture.querySelectorAll("span");
+      expect(spans.length).toBe(1);
+      expect(spans[0].className).toBe(`chimay-${phase} chimay-${phase}-active`);
+      cb();
+      expect(spans[0].className).toBe(`chimay-${phase}-active chimay-${phase}-to`);
+      def.resolve();
+    });
+
+    // click display the span
+    button!.click();
+    await def; // wait for the mocked repaint to be done
+    widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
+
+    // click to remove the span, and click again to re-add it before transitionend
+    def = makeDeferred();
+    phase = "leave";
+    button!.click();
+
+    await def; // wait for the mocked repaint to be done
+    def = makeDeferred();
+    phase = "enter";
+    button!.click();
+
+    await def; // wait for the mocked repaint to be done
+    widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
+  });
+
+  test("t-transition combined with t-component, remove and re-add before transitionend", async () => {
+    expect.assertions(11);
+
+    env.qweb.addTemplates(
+      `<templates>
+        <div t-name="Parent">
+          <button t-on-click="toggle">Toggle</button>
+          <t t-if="state.flag" t-component="Child" t-transition="chimay"/>
+        </div>
+        <span t-name="Child">blue</span>
+      </templates>`
+    );
+    class Child extends Widget {}
+    class Parent extends Widget {
+      components = { Child };
+      constructor(parent) {
+        super(parent);
+        this.state = { flag: false };
+      }
+      toggle() {
+        this.state.flag = !this.state.flag;
+      }
+    }
+
+    const widget = new Parent(env);
+    await widget.mount(fixture);
+    let button = widget.el!.querySelector("button");
+
+    let def = makeDeferred();
+    let phase = "enter";
+    patchNextFrame(cb => {
+      let spans = fixture.querySelectorAll("span");
+      expect(spans.length).toBe(1);
+      expect(spans[0].className).toBe(`chimay-${phase} chimay-${phase}-active`);
+      cb();
+      expect(spans[0].className).toBe(`chimay-${phase}-active chimay-${phase}-to`);
+      def.resolve();
+    });
+
+    // click display the span
+    button!.click();
+    await def; // wait for the mocked repaint to be done
+    widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
+
+    // click to remove the span, and click again to re-add it before transitionend
+    def = makeDeferred();
+    phase = "leave";
+    button!.click();
+
+    await def; // wait for the mocked repaint to be done
+    def = makeDeferred();
+    phase = "enter";
+    button!.click();
+
+    await def; // wait for the mocked repaint to be done
+    widget.el!.querySelector("span")!.dispatchEvent(new Event("transitionend")); // mock end of css transition
+    expect(fixture.innerHTML).toBe('<div><button>Toggle</button><span class="">blue</span></div>');
+  });
+});

tests/doc_link_checker.test.ts

@@ -0,0 +1,126 @@
+/**
+ * Doc Link Checker
+ *
+ * We define here a test to make sure that there are no dead link in the Owl
+ * documentation.
+ */
+import * as fs from "fs";
+
+const LINK_REGEXP = /\[([^\[]+)\]\(([^\)]+)\)/g;
+const HEADING_REGEXP = /\n(#+\s*)(.*)/g;
+
+// files to be checked
+function getFiles(): string[] {
+  const DOCFILES = fs.readdirSync("doc").map(f => `doc/${f}`);
+  const MAINREADME = "README.md";
+  return DOCFILES.concat(MAINREADME);
+}
+
+test("All markdown links work", () => {
+  let linkNumber = 0;
+  let invalidLinkNumber = 0;
+  const files = getFiles();
+  const data = readDocData(files);
+  for (let file of data) {
+    for (let link of file.links) {
+      // DEBUG: uncomment next line
+      // console.warn(`Checking "${link.name}" in "${file.name}"`);
+      linkNumber++;
+      if (!isLinkValid(link, file, data)) {
+        console.warn(`Invalid Link: "${link.name}" in "${file.name}"`);
+        invalidLinkNumber++;
+      }
+    }
+  }
+  expect(invalidLinkNumber).toBe(0);
+  expect(linkNumber).toBeGreaterThan(10);
+});
+
+interface MarkDownLink {
+  name: string;
+  link: string;
+}
+
+interface MarkDownSection {
+  name: string;
+  slug: string;
+}
+
+interface FileData {
+  name: string;
+  links: MarkDownLink[];
+  sections: MarkDownSection[];
+}
+
+function isLinkValid(link: MarkDownLink, current: FileData, files: FileData[]): boolean {
+  const parts = link.link.split("#");
+  const currentParts = current.name.split("/");
+  const path = currentParts.length > 1 ? currentParts[0] + "/" : "";
+  const fullName = path + parts[0];
+  if (parts.length === 1) {
+    // no # in url
+    if (parts[0].endsWith(".md")) {
+      // it is a local md file
+      if (!files.find(f => f.name === fullName)) {
+        return false;
+      }
+    }
+  } else {
+    const file = parts[0] === "" ? current : files.find(f => f.name === fullName);
+    if (!file) {
+      return false;
+    }
+    if (!file.sections.find(s => s.slug === parts[1])) {
+      return false;
+    }
+  }
+  return true;
+}
+// adapted from https://medium.com/@mhagemann/the-ultimate-way-to-slugify-a-url-string-in-javascript-b8e4a0d849e1
+function slugify(str) {
+  const a = "àáäâãåăæçèéëêǵḧìíïîḿńǹñòóöôœøṕŕßśșțùúüûǘẃẍÿź·_,:;";
+  const b = "aaaaaaaaceeeeghiiiimnnnooooooprssstuuuuuwxyz-----";
+  const p = new RegExp(a.split("").join("|"), "g");
+  return str
+    .toString()
+    .toLowerCase()
+    .replace(/\//g, "") // remove /
+    .replace(/\s+/g, "-") // Replace spaces with -
+    .replace(p, c => b.charAt(a.indexOf(c))) // Replace special characters
+    .replace(/&/g, "-and-") // Replace & with ‘and’
+    .replace(/[^\w\-]+/g, "") // Remove all non-word characters
+    .replace(/\-\-+/g, "-") // Replace multiple - with single -
+    .replace(/^-+/, "") // Trim - from start of text
+    .replace(/-+$/, ""); // Trim - from end of text
+}
+
+function readDocData(files: string[]): FileData[] {
+  const result: FileData[] = [];
+
+  for (let file of files) {
+    const fileData: FileData = {
+      name: file,
+      links: [],
+      sections: []
+    };
+    const content = fs.readFileSync(file, { encoding: "utf8" });
+    let m;
+    // get links info
+    do {
+      m = LINK_REGEXP.exec(content);
+      if (m) {
+        fileData.links.push({ name: m[0], link: m[2] });
+      }
+    } while (m);
+    // get sections info
+    do {
+      m = HEADING_REGEXP.exec(content);
+      if (m) {
+        fileData.sections.push({ name: m[0], slug: slugify(m[2]) });
+      }
+    } while (m);
+
+    result.push(fileData);
+  }
+  return result;
+}

tests/event_bus.test.ts

@@ -23,9 +23,7 @@ describe("event bus behaviour", () => {
   test("throw error if callback is undefined", () => {
     expect.assertions(1);
     const bus = new EventBus();
-    expect(() => bus.on("event", {}, <any>undefined)).toThrow(
-      `Missing callback`
-    );
+    expect(() => bus.on("event", {}, <any>undefined)).toThrow(`Missing callback`);
   });
 
   test("can unsubscribe", () => {

tests/helpers.ts

@@ -1,5 +1,8 @@
 import { Env } from "../src/component";
-import { QWeb } from "../src/qweb";
+import { EvalContext, QWeb, UTILS } from "../src/qweb_core";
+import { patch } from "../src/vdom";
+import "../src/qweb_directives";
+import "../src/qweb_extensions";
 
 export function nextMicroTick(): Promise<void> {
   return Promise.resolve();
@@ -35,8 +38,59 @@ export function makeDeferred(): Deferred {
   return <Deferred>def;
 }
 
-export function makeTestWEnv(): Env {
+export function makeTestEnv(): Env {
   return {
     qweb: new QWeb()
   };
 }
+
+export function trim(str: string): string {
+  return str.replace(/\s/g, "");
+}
+
+export function renderToDOM(
+  qweb: QWeb,
+  template: string,
+  context: EvalContext = {},
+  extra?: any
+): HTMLElement | Text {
+  const vnode = qweb.render(template, context, extra);
+
+  // we snapshot here the compiled code. This is useful to prevent unwanted code
+  // change.
+  expect(qweb.templates[template].fn.toString()).toMatchSnapshot();
+
+  if (vnode.sel === undefined) {
+    return document.createTextNode(vnode.text!);
+  }
+  const node = document.createElement(vnode.sel!);
+  const result = patch(node, vnode);
+  return result.elm as HTMLElement;
+}
+
+export function renderToString(qweb: QWeb, t: string, context: EvalContext = {}): string {
+  const node = renderToDOM(qweb, t, context);
+  return node instanceof Text ? node.textContent! : node.outerHTML;
+}
+
+// hereafter, we define two helpers to patch/unpatch the nextFrame utils. This
+// is useful for animations tests, as we hook before repaints to trigger
+// animations (thanks to requestAnimationFrame). Patching nextFrame allows to
+// simulate calls to this hook. One must not forget to unpatch afterwards.
+let nextFrame = UTILS.nextFrame;
+export function patchNextFrame(f: Function) {
+  UTILS.nextFrame = (cb: () => void) => {
+    setTimeout(() => f(cb));
+  };
+}
+
+export function unpatchNextFrame() {
+  UTILS.nextFrame = nextFrame;
+}
+
+export async function editInput(input: HTMLInputElement | HTMLTextAreaElement, value: string) {
+  input.value = value;
+  input.dispatchEvent(new Event("input"));
+  input.dispatchEvent(new Event("change"));
+  return nextTick();
+}

tests/observer.test.ts

@@ -126,12 +126,63 @@ describe("observer", () => {
     arr.push({ kriek: 5 });
     expect(observer.rev).toBe(2);
     expect(arr.__owl__.rev).toBe(2);
-    expect(arr[0].__owl__.rev).toBe(1);
+    expect(arr[0].__owl__.rev).toBe(2);
 
     arr[0].kriek = 6;
     expect(observer.rev).toBe(3);
     expect(arr.__owl__.rev).toBe(2);
-    expect(arr[0].__owl__.rev).toBe(2);
+    expect(arr[0].__owl__.rev).toBe(3);
+  });
+
+  test("set new property on observed object", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = { a: 1 };
+    observer.observe(state);
+    expect(state.__owl__.rev).toBe(1);
+    expect(observer.rev).toBe(1);
+    expect(observer.notifyCB).toBeCalledTimes(0);
+
+    Observer.set(state, "b", 8);
+    await nextMicroTick();
+    expect(state.__owl__.rev).toBe(2);
+    expect(observer.rev).toBe(2);
+    expect(observer.notifyCB).toBeCalledTimes(1);
+    expect(state.b).toBe(8);
+  });
+
+  test("delete property from observed object", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = { a: 1, b: 8 };
+    observer.observe(state);
+    expect(state.__owl__.rev).toBe(1);
+    expect(observer.rev).toBe(1);
+    expect(observer.notifyCB).toBeCalledTimes(0);
+
+    Observer.delete(state, "b");
+    await nextMicroTick();
+    expect(state.__owl__.rev).toBe(2);
+    expect(observer.rev).toBe(2);
+    expect(observer.notifyCB).toBeCalledTimes(1);
+    expect(state).toEqual({ a: 1 });
+  });
+
+  test("set element in observed array", async () => {
+    const observer = new Observer();
+    observer.notifyCB = jest.fn();
+    const state: any = ["a"];
+    observer.observe(state);
+    expect(state.__owl__.rev).toBe(1);
+    expect(observer.rev).toBe(1);
+    expect(observer.notifyCB).toBeCalledTimes(0);
+
+    Observer.set(state, 1, "b");
+    await nextMicroTick();
+    expect(state.__owl__.rev).toBe(2);
+    expect(observer.rev).toBe(2);
+    expect(observer.notifyCB).toBeCalledTimes(1);
+    expect(state).toEqual(["a", "b"]);
   });
 
   test("properly observe arrays in object", () => {
@@ -180,12 +231,14 @@ describe("observer", () => {
     obj.a = { b: 2 };
     expect(observer.rev).toBe(2);
     expect(obj.__owl__.rev).toBe(2);
-    expect(obj.a.__owl__.rev).toBe(1);
+
+    // we start at 2 because it is the new observer rev number
+    expect(obj.a.__owl__.rev).toBe(2);
 
     obj.a.b = 3;
     expect(observer.rev).toBe(3);
     expect(obj.__owl__.rev).toBe(2);
-    expect(obj.a.__owl__.rev).toBe(2);
+    expect(obj.a.__owl__.rev).toBe(3);
   });
 
   test("deep observe misc changes", () => {
@@ -228,6 +281,26 @@ describe("observer", () => {
     expect(obj2.__owl__.rev).toBe(3);
   });
 
+  test("can set a property more than once", () => {
+    const observer = new Observer();
+    const obj: any = {};
+
+    observer.observe(obj);
+    expect(obj.__owl__.rev).toBe(1);
+    expect(observer.rev).toBe(1);
+    expect(obj.__owl__.deepRev).toBe(1);
+
+    observer.set(obj, "aku", "always finds annoying problems");
+    expect(observer.rev).toBe(2);
+    expect(obj.__owl__.rev).toBe(2);
+    expect(obj.__owl__.deepRev).toBe(2);
+
+    observer.set(obj, "aku", "always finds good problems");
+    expect(observer.rev).toBe(3);
+    expect(obj.__owl__.rev).toBe(3);
+    expect(obj.__owl__.deepRev).toBe(3);
+  });
+
   test("properly handle swapping elements", () => {
     const observer = new Observer();
     const obj: any = { a: { arr: [] }, b: 1 };

tests/props_validation.test.ts

@@ -0,0 +1,258 @@
+import { Component, Env } from "../src/component";
+import { makeTestFixture, makeTestEnv } from "./helpers";
+import { QWeb } from "../src";
+
+//------------------------------------------------------------------------------
+// Setup and helpers
+//------------------------------------------------------------------------------
+
+let fixture: HTMLElement;
+let env: Env;
+let dev: boolean = false;
+
+beforeEach(() => {
+  fixture = makeTestFixture();
+  env = makeTestEnv();
+  dev = QWeb.dev;
+  QWeb.dev = true;
+});
+
+afterEach(() => {
+  fixture.remove();
+  QWeb.dev = dev;
+});
+
+class Widget extends Component<any, any, any> {}
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+describe("props validation", () => {
+  test("validation is only done in dev mode", async () => {
+    class TestWidget extends Widget {
+      static props = ["message"];
+    }
+
+    QWeb.dev = true;
+    expect(() => {
+      new TestWidget(env);
+    }).toThrow();
+
+    QWeb.dev = false;
+
+    expect(() => {
+      new TestWidget(env);
+    }).not.toThrow();
+  });
+
+  test("props validation is also done on update props", async () => {
+    expect.assertions(1);
+    class TestWidget extends Widget {
+      static props = ["message"];
+    }
+    const w = new TestWidget(env, { message: "bottle" });
+    try {
+      await w.__updateProps({});
+    } catch (e) {
+      expect(e.message).toBe("Missing props 'message' (component 'TestWidget')");
+    }
+  });
+
+  test("props: list of strings", async () => {
+    class TestWidget extends Widget {
+      static props = ["message"];
+    }
+
+    expect(() => {
+      new TestWidget(env);
+    }).toThrow("Missing props 'message' (component 'TestWidget')");
+  });
+
+  test("validate simple types", async () => {
+    const Tests = [
+      { type: Number, ok: 1, ko: "1" },
+      { type: Boolean, ok: true, ko: "1" },
+      { type: String, ok: "1", ko: 1 },
+      { type: Object, ok: {}, ko: "1" },
+      { type: Date, ok: new Date(), ko: "1" },
+      { type: Function, ok: () => {}, ko: "1" }
+    ];
+
+    for (let test of Tests) {
+      let TestWidget = class extends Widget {
+        static props = { p: test.type };
+      };
+
+      expect(() => {
+        new TestWidget(env);
+      }).toThrow("Missing props 'p'");
+
+      expect(() => {
+        new TestWidget(env, { p: test.ok });
+      }).not.toThrow();
+
+      expect(() => {
+        new TestWidget(env, { p: test.ko });
+      }).toThrow("Props 'p' of invalid type in component");
+    }
+  });
+
+  test("validate simple types, alternate form", async () => {
+    const Tests = [
+      { type: Number, ok: 1, ko: "1" },
+      { type: Boolean, ok: true, ko: "1" },
+      { type: String, ok: "1", ko: 1 },
+      { type: Object, ok: {}, ko: "1" },
+      { type: Date, ok: new Date(), ko: "1" },
+      { type: Function, ok: () => {}, ko: "1" }
+    ];
+
+    for (let test of Tests) {
+      let TestWidget = class extends Widget {
+        static props = { p: { type: test.type } };
+      };
+
+      expect(() => {
+        new TestWidget(env);
+      }).toThrow("Missing props 'p'");
+
+      expect(() => {
+        new TestWidget(env, { p: test.ok });
+      }).not.toThrow();
+
+      expect(() => {
+        new TestWidget(env, { p: test.ko });
+      }).toThrow("Props 'p' of invalid type in component");
+    }
+  });
+
+  test("can validate a prop with multiple types", async () => {
+    let TestWidget = class extends Widget {
+      static props = { p: [String, Boolean] };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: "string" });
+      new TestWidget(env, { p: true });
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: 1 });
+    }).toThrow("Props 'p' of invalid type in component");
+  });
+
+  test("can validate an optional props", async () => {
+    let TestWidget = class extends Widget {
+      static props = { p: { type: String, optional: true } };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: "hey" });
+      new TestWidget(env, {});
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: 1 });
+    }).toThrow();
+  });
+
+  test("can validate an array with given primitive type", async () => {
+    let TestWidget = class extends Widget {
+      static props = { p: { type: Array, element: String } };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: [] });
+      new TestWidget(env, { p: ["string"] });
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: [1] });
+    }).toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: ["string", 1] });
+    }).toThrow();
+  });
+
+  test("can validate an array with multiple sub element types", async () => {
+    let TestWidget = class extends Widget {
+      static props = { p: { type: Array, element: [String, Boolean] } };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: [] });
+      new TestWidget(env, { p: ["string"] });
+      new TestWidget(env, { p: [false, true, "string"] });
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: [true, 1] });
+    }).toThrow();
+  });
+
+  test("can validate an object with simple shape", async () => {
+    let TestWidget = class extends Widget {
+      static props = {
+        p: { type: Object, shape: { id: Number, url: String } }
+      };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: { id: 1, url: "url" } });
+      new TestWidget(env, { p: { id: 1, url: "url", extra: true } });
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: { id: "1", url: "url" } });
+    }).toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: { id: 1 } });
+    }).toThrow();
+  });
+
+  test("can validate recursively complicated prop def", async () => {
+    let TestWidget = class extends Widget {
+      static props = {
+        p: {
+          type: Object,
+          shape: {
+            id: Number,
+            url: [Boolean, { type: Array, element: Number }]
+          }
+        }
+      };
+    };
+
+    expect(() => {
+      new TestWidget(env, { p: { id: 1, url: true } });
+      new TestWidget(env, { p: { id: 1, url: [12] } });
+    }).not.toThrow();
+
+    expect(() => {
+      new TestWidget(env, { p: { id: 1, url: [12, true] } });
+    }).toThrow();
+  });
+});
+
+describe("default props", () => {
+  test("can set default values", async () => {
+    class TestWidget extends Widget {
+      static defaultProps = { p: 4 };
+    }
+
+    const w = new TestWidget(env, {});
+    expect(w.props.p).toBe(4);
+  });
+
+  test("default values are also set whenever component is updated", async () => {
+    class TestWidget extends Widget {
+      static defaultProps = { p: 4 };
+    }
+
+    const w = new TestWidget(env, { p: 1 });
+    await w.__updateProps({});
+    expect(w.props.p).toBe(4);
+  });
+});

tests/qweb.test.ts

@@ -1,6 +1,5 @@
-import { EvalContext, QWeb } from "../src/qweb";
-import { patch } from "../src/vdom";
-import { normalize } from "./helpers";
+import { QWeb } from "../src/qweb_core";
+import { normalize, renderToDOM, renderToString, trim } from "./helpers";
 
 //------------------------------------------------------------------------------
 // Setup and helpers
@@ -15,39 +14,6 @@ beforeEach(() => {
   qweb = new QWeb();
 });
 
-function trim(str: string): string {
-  return str.replace(/\s/g, "");
-}
-
-function renderToDOM(
-  qweb: QWeb,
-  template: string,
-  context: EvalContext = {},
-  extra?: any
-): HTMLElement | Text {
-  const vnode = qweb.render(template, context, extra);
-
-  // we snapshot here the compiled code. This is useful to prevent unwanted code
-  // change.
-  expect(qweb.templates[template].fn.toString()).toMatchSnapshot();
-
-  if (vnode.sel === undefined) {
-    return document.createTextNode(vnode.text!);
-  }
-  const node = document.createElement(vnode.sel!);
-  const result = patch(node, vnode);
-  return result.elm as HTMLElement;
-}
-
-function renderToString(
-  qweb: QWeb,
-  t: string,
-  context: EvalContext = {}
-): string {
-  const node = renderToDOM(qweb, t, context);
-  return node instanceof Text ? node.textContent! : node.outerHTML;
-}
-
 //------------------------------------------------------------------------------
 // Tests
 //------------------------------------------------------------------------------
@@ -58,6 +24,16 @@ describe("static templates", () => {
     expect(renderToString(qweb, "test")).toBe("hello vdom");
   });
 
+  test("simple dynamic value", () => {
+    qweb.addTemplate("test", '<t><t t-esc="text"/></t>');
+    expect(renderToString(qweb, "test", { text: "hello vdom" })).toBe("hello vdom");
+  });
+
+  test("simple string, with some dynamic value", () => {
+    qweb.addTemplate("test", '<t>hello <t t-esc="text"/></t>');
+    expect(renderToString(qweb, "test", { text: "vdom" })).toBe("hello vdom");
+  });
+
   test("empty div", () => {
     qweb.addTemplate("test", "<div></div>");
     expect(renderToString(qweb, "test")).toBe("<div></div>");
@@ -76,9 +52,7 @@ describe("static templates", () => {
 
 describe("error handling", () => {
   test("invalid xml", () => {
-    expect(() => qweb.addTemplate("test", "<div>")).toThrow(
-      "Invalid XML in template"
-    );
+    expect(() => qweb.addTemplate("test", "<div>")).toThrow("Invalid XML in template");
   });
 
   test("template with text node and tag", () => {
@@ -95,12 +69,13 @@ describe("error handling", () => {
 
   test("cannot add twice the same template", () => {
     qweb.addTemplate("test", `<t></t>`);
+    expect(() => qweb.addTemplate("test", "<div/>", true)).not.toThrow("already defined");
     expect(() => qweb.addTemplate("test", "<div/>")).toThrow("already defined");
   });
 
   test("loadTemplates throw if parser error", () => {
     expect(() => {
-      qweb.loadTemplates("<templates><abc>></templates>");
+      qweb.addTemplates("<templates><abc>></templates>");
     }).toThrow("Invalid XML in template");
   });
 
@@ -113,29 +88,14 @@ describe("error handling", () => {
 
   test("nice error when t-on is evaluated with a missing event", () => {
     qweb.addTemplate("templatename", `<div t-on="somemethod"></div>`);
-    expect(() =>
-      qweb.render("templatename", { someMethod() {} }, { handlers: [] })
-    ).toThrow("Missing event name with t-on directive");
-  });
-
-  test("error when compiled code is invalid", () => {
-    qweb.addTemplate(
-      "templatename",
-      `<div t-att-hey="}/^function invalid{{>'"></div>`
-    );
-    expect(() => qweb.render("templatename")).toThrow(
-      "Invalid generated code while compiling template 'templatename': Unexpected token }"
+    expect(() => qweb.render("templatename", { someMethod() {} }, { handlers: [] })).toThrow(
+      "Missing event name with t-on directive"
     );
   });
 
   test("error when unknown directive", () => {
-    qweb.addTemplate(
-      "templatename",
-      `<div t-best-beer="rochefort 10">test</div>`
-    );
-    expect(() => qweb.render("templatename")).toThrow(
-      "Unknown QWeb directive: 't-best-beer'"
-    );
+    qweb.addTemplate("templatename", `<div t-best-beer="rochefort 10">test</div>`);
+    expect(() => qweb.render("templatename")).toThrow("Unknown QWeb directive: 't-best-beer'");
   });
 });
 
@@ -152,9 +112,7 @@ describe("t-esc", () => {
 
   test.skip("escaping", () => {
     qweb.addTemplate("test", `<span><t t-esc="var"/></span>`);
-    expect(renderToString(qweb, "test", { var: "<ok>" })).toBe(
-      "<span>&lt;ok&gt;</span>"
-    );
+    expect(renderToString(qweb, "test", { var: "<ok>" })).toBe("<span>&lt;ok&gt;</span>");
   });
 
   test("escaping on a node", () => {
@@ -186,9 +144,7 @@ describe("t-raw", () => {
 
   test("not escaping", () => {
     qweb.addTemplate("test", `<div><t t-raw="var"/></div>`);
-    expect(renderToString(qweb, "test", { var: "<ok></ok>" })).toBe(
-      "<div><ok></ok></div>"
-    );
+    expect(renderToString(qweb, "test", { var: "<ok></ok>" })).toBe("<div><ok></ok></div>");
   });
 
   test("t-raw and another sibling node", () => {
@@ -201,39 +157,28 @@ describe("t-raw", () => {
 
 describe("t-set", () => {
   test("set from attribute literal", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="'ok'"/><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="'ok'"/><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>ok</div>");
   });
 
   test("t-set and t-if", () => {
     qweb.addTemplate(
       "test",
-      `<div >
+      `<div>
         <t t-set="v" t-value="value"/>
         <t t-if="v === 'ok'">grimbergen</t>
         </div>`
     );
-    expect(renderToString(qweb, "test", { value: "ok" })).toBe(
-      "<div>grimbergen</div>"
-    );
+    expect(renderToString(qweb, "test", { value: "ok" })).toBe("<div>grimbergen</div>");
   });
 
   test("set from body literal", () => {
-    qweb.addTemplate(
-      "test",
-      `<t><t t-set="value">ok</t><t t-esc="value"/></t>`
-    );
+    qweb.addTemplate("test", `<t><t t-set="value">ok</t><t t-esc="value"/></t>`);
     expect(renderToString(qweb, "test")).toBe("ok");
   });
 
   test("set from attribute lookup", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="stuff" t-value="value"/><t t-esc="stuff"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="stuff" t-value="value"/><t t-esc="stuff"/></div>`);
     expect(renderToString(qweb, "test", { value: "ok" })).toBe("<div>ok</div>");
   });
 
@@ -265,18 +210,12 @@ describe("t-set", () => {
   });
 
   test("value priority", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="1">2</t><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="1">2</t><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>1</div>");
   });
 
   test("evaluate value expression", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-set="value" t-value="1 + 2"/><t t-esc="value"/></div>`
-    );
+    qweb.addTemplate("test", `<div><t t-set="value" t-value="1 + 2"/><t t-esc="value"/></div>`);
     expect(renderToString(qweb, "test")).toBe("<div>3</div>");
   });
 
@@ -301,25 +240,19 @@ describe("t-set", () => {
       "test",
       `<div><t t-set="value" t-value="somevariable + 2"/><t t-esc="value"/></div>`
     );
-    expect(renderToString(qweb, "test", { somevariable: 43 })).toBe(
-      "<div>45</div>"
-    );
+    expect(renderToString(qweb, "test", { somevariable: 43 })).toBe("<div>45</div>");
   });
 });
 
 describe("t-if", () => {
   test("boolean value true condition", () => {
     qweb.addTemplate("test", `<div><t t-if="condition">ok</t></div>`);
-    expect(renderToString(qweb, "test", { condition: true })).toBe(
-      "<div>ok</div>"
-    );
+    expect(renderToString(qweb, "test", { condition: true })).toBe("<div>ok</div>");
   });
 
   test("boolean value false condition", () => {
     qweb.addTemplate("test", `<div><t t-if="condition">ok</t></div>`);
-    expect(renderToString(qweb, "test", { condition: false })).toBe(
-      "<div></div>"
-    );
+    expect(renderToString(qweb, "test", { condition: false })).toBe("<div></div>");
   });
 
   test("boolean value condition missing", () => {
@@ -336,9 +269,7 @@ describe("t-if", () => {
         <t t-else="">beer</t></div>
     `
     );
-    expect(renderToString(qweb, "test", { color: "red" })).toBe(
-      "<div>red is dead</div>"
-    );
+    expect(renderToString(qweb, "test", { color: "red" })).toBe("<div>red is dead</div>");
   });
 
   test("boolean value condition else", () => {
@@ -364,9 +295,7 @@ describe("t-if", () => {
         `
     );
     const result = trim(renderToString(qweb, "test", { condition: false }));
-    expect(result).toBe(
-      "<div><span>begin</span>fail-else<span>end</span></div>"
-    );
+    expect(result).toBe("<div><span>begin</span>fail-else<span>end</span></div>");
   });
 
   test("can use some boolean operators in expressions", () => {
@@ -391,9 +320,7 @@ describe("t-if", () => {
       m: 5,
       n: 2
     };
-    expect(normalize(renderToString(qweb, "test", context))).toBe(
-      "<div>andormgtnlt</div>"
-    );
+    expect(normalize(renderToString(qweb, "test", context))).toBe("<div>andormgtnlt</div>");
   });
 });
 
@@ -511,11 +438,14 @@ describe("attributes", () => {
     expect(result).toBe(`<div foo="42"></div>`);
   });
 
+  test("format expression, other format", () => {
+    qweb.addTemplate("test", `<div t-attf-foo="{{value + 37}}"/>`);
+    const result = renderToString(qweb, "test", { value: 5 });
+    expect(result).toBe(`<div foo="42"></div>`);
+  });
+
   test("format multiple", () => {
-    qweb.addTemplate(
-      "test",
-      `<div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>`
-    );
+    qweb.addTemplate("test", `<div t-attf-foo="a {{value1}} is {{value2}} of {{value3}} ]"/>`);
     const result = renderToString(qweb, "test", {
       value1: 0,
       value2: 1,
@@ -550,11 +480,14 @@ describe("attributes", () => {
     expect(result).toBe(`<div class="hello world"></div>`);
   });
 
+  test("class and t-attf-class with ternary operation", () => {
+    qweb.addTemplate("test", `<div class="hello" t-attf-class="{{value ? 'world' : ''}}"/>`);
+    const result = renderToString(qweb, "test", { value: true });
+    expect(result).toBe(`<div class="hello world"></div>`);
+  });
+
   test("t-att-class with object", () => {
-    qweb.addTemplate(
-      "test",
-      `<div class="static" t-att-class="{a: b, c: d, e: f}"/>`
-    );
+    qweb.addTemplate("test", `<div class="static" t-att-class="{a: b, c: d, e: f}"/>`);
     const result = renderToString(qweb, "test", { b: true, d: false, f: true });
     expect(result).toBe(`<div class="static a e"></div>`);
   });
@@ -583,10 +516,7 @@ describe("t-call (template calling", () => {
 
   test("with unused setbody", () => {
     qweb.addTemplate("_basic-callee", "<div>ok</div>");
-    qweb.addTemplate(
-      "caller",
-      '<t t-call="_basic-callee"><t t-set="qux" t-value="3"/></t>'
-    );
+    qweb.addTemplate("caller", '<t t-call="_basic-callee"><t t-set="qux" t-value="3"/></t>');
     const expected = "<div>ok</div>";
     expect(renderToString(qweb, "caller")).toBe(expected);
   });
@@ -672,25 +602,13 @@ describe("foreach", () => {
       "test",
       `
       <div>
-        <t t-foreach="5" t-as="elem">
-          -<t t-if="elem_first"> first</t><t t-if="elem_last"> last</t> (<t t-esc="elem_parity"/>)
+        <t t-foreach="Array(5)" t-as="elem">
+          -<t t-if="elem_first"> first</t><t t-if="elem_last"> last</t> (<t t-esc="elem_index"/>)
         </t>
       </div>`
     );
     const result = trim(renderToString(qweb, "test"));
-    const expected = `<div>-first(even)-(odd)-(even)-(odd)-last(even)</div>`;
-    expect(result).toBe(expected);
-  });
-
-  test("iterate, integer param", () => {
-    qweb.addTemplate(
-      "test",
-      `<div><t t-foreach="3" t-as="item">
-        [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
-      </t></div>`
-    );
-    const result = trim(renderToString(qweb, "test"));
-    const expected = `<div>[0:00][1:11][2:22]</div>`;
+    const expected = `<div>-first(0)-(1)-(2)-(3)-last(4)</div>`;
     expect(result).toBe(expected);
   });
 
@@ -700,14 +618,12 @@ describe("foreach", () => {
       `
       <div>
         <t t-foreach="value" t-as="item">
-          [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/> - <t t-esc="item_parity"/>]
+          [<t t-esc="item_index"/>: <t t-esc="item"/> <t t-esc="item_value"/>]
         </t>
       </div>`
     );
-    const result = trim(
-      renderToString(qweb, "test", { value: { a: 1, b: 2, c: 3 } })
-    );
-    const expected = `<div>[0:a1-even][1:b2-odd][2:c3-even]</div>`;
+    const result = trim(renderToString(qweb, "test", { value: { a: 1, b: 2, c: 3 } }));
+    const expected = `<div>[0:a1][1:b2][2:c3]</div>`;
     expect(result).toBe(expected);
   });
 
@@ -748,20 +664,13 @@ describe("foreach", () => {
     expect(console.warn).toHaveBeenCalledTimes(1);
     console.warn = consoleWarn;
   });
-
 });
 
 describe("misc", () => {
   test("global", () => {
     qweb.addTemplate("_callee-asc", `<Año t-att-falló="'agüero'" t-raw="0"/>`);
-    qweb.addTemplate(
-      "_callee-uses-foo",
-      `<span t-esc="foo">foo default</span>`
-    );
-    qweb.addTemplate(
-      "_callee-asc-toto",
-      `<div t-raw="toto">toto default</div>`
-    );
+    qweb.addTemplate("_callee-uses-foo", `<span t-esc="foo">foo default</span>`);
+    qweb.addTemplate("_callee-asc-toto", `<div t-raw="toto">toto default</div>`);
     qweb.addTemplate(
       "caller",
       `
@@ -874,10 +783,7 @@ describe("t-on", () => {
   });
 
   test("can bind handlers with object arguments", () => {
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="add({val: 5})">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="add({val: 5})">Click</button>`);
     let a = 1;
     const node = renderToDOM(
       qweb,
@@ -895,10 +801,7 @@ describe("t-on", () => {
 
   test("can bind handlers with empty object", () => {
     expect.assertions(2);
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="doSomething({})">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="doSomething({})">Click</button>`);
     const node = renderToDOM(
       qweb,
       "test",
@@ -912,12 +815,9 @@ describe("t-on", () => {
     (<HTMLElement>node).click();
   });
 
-  test("can bind handlers with empty object (with non empty inner string", () => {
+  test("can bind handlers with empty object (with non empty inner string)", () => {
     expect.assertions(2);
-    qweb.addTemplate(
-      "test",
-      `<button t-on-click="doSomething({ })">Click</button>`
-    );
+    qweb.addTemplate("test", `<button t-on-click="doSomething({ })">Click</button>`);
     const node = renderToDOM(
       qweb,
       "test",
@@ -964,32 +864,147 @@ describe("t-on", () => {
     const node = renderToDOM(qweb, "test", owner, { handlers: [] });
     (<HTMLElement>node).click();
   });
+
+  test("t-on with prevent and/or stop modifiers", async () => {
+    expect.assertions(7);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <button t-on-click.prevent="onClickPrevented">Button 1</button>
+        <button t-on-click.stop="onClickStopped">Button 2</button>
+        <button t-on-click.prevent.stop="onClickPreventedAndStopped">Button 3</button>
+      </div>`
+    );
+    let owner = {
+      onClickPrevented(e) {
+        expect(e.defaultPrevented).toBe(true);
+        expect(e.cancelBubble).toBe(false);
+      },
+      onClickStopped(e) {
+        expect(e.defaultPrevented).toBe(false);
+        expect(e.cancelBubble).toBe(true);
+      },
+      onClickPreventedAndStopped(e) {
+        expect(e.defaultPrevented).toBe(true);
+        expect(e.cancelBubble).toBe(true);
+      }
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+
+    const buttons = (<HTMLElement>node).getElementsByTagName("button");
+    buttons[0].click();
+    buttons[1].click();
+    buttons[2].click();
+  });
+
+  test("t-on with self modifier", async () => {
+    expect.assertions(2);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <button t-on-click="onClick"><span>Button</span></button>
+        <button t-on-click.self="onClickSelf"><span>Button</span></button>
+      </div>`
+    );
+    let steps: string[] = [];
+    let owner = {
+      onClick(e) {
+        steps.push("onClick");
+      },
+      onClickSelf(e) {
+        steps.push("onClickSelf");
+      }
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+
+    const buttons = (<HTMLElement>node).getElementsByTagName("button");
+    const spans = (<HTMLElement>node).getElementsByTagName("span");
+    spans[0].click();
+    spans[1].click();
+    buttons[0].click();
+    buttons[1].click();
+
+    expect(steps).toEqual(["onClick", "onClick", "onClickSelf"]);
+  });
+
+  test("t-on with self and prevent modifiers (order matters)", async () => {
+    expect.assertions(2);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <button t-on-click.self.prevent="onClick"><span>Button</span></button>
+      </div>`
+    );
+    let steps: boolean[] = [];
+    let owner = {
+      onClick() {}
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+    (<HTMLElement>node).addEventListener("click", function(e) {
+      steps.push(e.defaultPrevented);
+    });
+
+    const button = (<HTMLElement>node).getElementsByTagName("button")[0];
+    const span = (<HTMLElement>node).getElementsByTagName("span")[0];
+    span.click();
+    button.click();
+
+    expect(steps).toEqual([false, true]);
+  });
+
+  test("t-on with prevent and self modifiers (order matters)", async () => {
+    expect.assertions(2);
+    qweb.addTemplate(
+      "test",
+      `<div>
+        <button t-on-click.prevent.self="onClick"><span>Button</span></button>
+      </div>`
+    );
+    let steps: boolean[] = [];
+    let owner = {
+      onClick() {}
+    };
+    const node = renderToDOM(qweb, "test", owner, { handlers: [] });
+    (<HTMLElement>node).addEventListener("click", function(e) {
+      steps.push(e.defaultPrevented);
+    });
+
+    const button = (<HTMLElement>node).getElementsByTagName("button")[0];
+    const span = (<HTMLElement>node).getElementsByTagName("span")[0];
+    span.click();
+    button.click();
+
+    expect(steps).toEqual([true, true]);
+  });
 });
 
 describe("t-ref", () => {
   test("can get a ref on a node", () => {
-    qweb.addTemplate("test", `<div><span t-ref="'myspan'"/></div>`);
+    qweb.addTemplate("test", `<div><span t-ref="myspan"/></div>`);
     let refs: any = {};
     renderToDOM(qweb, "test", { refs });
     expect(refs.myspan.tagName).toBe("SPAN");
   });
 
   test("can get a dynamic ref on a node", () => {
-    qweb.addTemplate("test", `<div><span t-ref="'myspan' + 3"/></div>`);
+    qweb.addTemplate("test", `<div><span t-ref="myspan{{id}}"/></div>`);
     let refs: any = {};
-    renderToDOM(qweb, "test", { refs });
+    renderToDOM(qweb, "test", { refs, id: 3 });
     expect(refs.myspan3.tagName).toBe("SPAN");
   });
 
   test("refs in a loop", () => {
-    qweb.addTemplate("test", `
+    qweb.addTemplate(
+      "test",
+      `
       <div>
         <t t-foreach="items" t-as="item">
-          <div t-ref="item" t-key="item"><t t-esc="item"/></div>
+          <div t-ref="{{item}}" t-key="item"><t t-esc="item"/></div>
         </t>
-      </div>`);
+      </div>`
+    );
     let refs: any = {};
-    renderToDOM(qweb, "test", { refs, items: [1,2,3] });
+    renderToDOM(qweb, "test", { refs, items: [1, 2, 3] });
     expect(Object.keys(refs)).toEqual(["1", "2", "3"]);
   });
 });
@@ -1014,15 +1029,15 @@ describe("loading templates", () => {
 
         <ul t-name="main"><t t-call="items"/></ul>
       </templates>`;
-    qweb.loadTemplates(data);
+    qweb.addTemplates(data);
     const result = renderToString(qweb, "main");
     expect(result).toBe("<ul><li>ok</li><li>foo</li></ul>");
   });
 
   test("does not crash if string does not have templates", () => {
     const data = "";
-    qweb.loadTemplates(data);
-    expect(qweb.templates).toEqual({});
+    qweb.addTemplates(data);
+    expect(Object.keys(qweb.templates)).toEqual([]);
   });
 });
 
@@ -1102,13 +1117,10 @@ describe("whitespace handling", () => {
 
 describe("t-key", () => {
   test("can use t-key directive on a node", () => {
-    qweb.addTemplate(
-      "test",
-      `<div t-key="beer.id"><t t-esc="beer.name"/></div>`
+    qweb.addTemplate("test", `<div t-key="beer.id"><t t-esc="beer.name"/></div>`);
+    expect(renderToString(qweb, "test", { beer: { id: 12, name: "Chimay Rouge" } })).toBe(
+      "<div>Chimay Rouge</div>"
     );
-    expect(
-      renderToString(qweb, "test", { beer: { id: 12, name: "Chimay Rouge" } })
-    ).toBe("<div>Chimay Rouge</div>");
   });
 
   test("t-key directive in a list", () => {
@@ -1159,16 +1171,3 @@ describe("debugging", () => {
     console.log = consoleLog;
   });
 });
-
-describe("animations", () => {
-  test("t-transition, on a simple node", async () => {
-    // this test does not test much, because it is not easy to test timing
-    // transitions... we should do a little more effort for these tests.
-    qweb.addTemplate(
-      "test",
-      `<div><span t-transition="chimay">blue</span></div>`
-    );
-    let dom: HTMLElement = <HTMLElement>renderToDOM(qweb, "test");
-    expect(dom.innerHTML).toMatchSnapshot();
-  });
-});

tests/qweb_expressions.test.ts

@@ -0,0 +1,158 @@
+import { compileExpr, tokenize } from "../src/qweb_expressions";
+
+describe("tokenizer", () => {
+  test("simple tokens", () => {
+    expect(tokenize("1.3")).toEqual([{ type: "VALUE", value: "1.3" }]);
+
+    expect(tokenize("{}")).toEqual([
+      { type: "LEFT_BRACE", value: "{" },
+      { type: "RIGHT_BRACE", value: "}" }
+    ]);
+    expect(tokenize("{ }}")).toEqual([
+      { type: "LEFT_BRACE", value: "{" },
+      { type: "RIGHT_BRACE", value: "}" },
+      { type: "RIGHT_BRACE", value: "}" }
+    ]);
+    expect(tokenize("a")).toEqual([{ type: "SYMBOL", value: "a" }]);
+    expect(tokenize("true")).toEqual([{ type: "SYMBOL", value: "true" }]);
+    expect(tokenize("abcde")).toEqual([{ type: "SYMBOL", value: "abcde" }]);
+    expect(tokenize("_ab2")).toEqual([{ type: "SYMBOL", value: "_ab2" }]);
+    expect(tokenize("$ab2")).toEqual([{ type: "SYMBOL", value: "$ab2" }]);
+    expect(tokenize("ABC")).toEqual([{ type: "SYMBOL", value: "ABC" }]);
+
+    expect(tokenize("{a: 2}")).toEqual([
+      { type: "LEFT_BRACE", value: "{" },
+      { type: "SYMBOL", value: "a" },
+      { type: "COLON", value: ":" },
+      { type: "VALUE", value: "2" },
+      { type: "RIGHT_BRACE", value: "}" }
+    ]);
+    expect(tokenize("a,")).toEqual([{ type: "SYMBOL", value: "a" }, { type: "COMMA", value: "," }]);
+    expect(tokenize("][")).toEqual([
+      { type: "RIGHT_BRACKET", value: "]" },
+      { type: "LEFT_BRACKET", value: "[" }
+    ]);
+  });
+
+  test("various operators", () => {
+    expect(tokenize(">= <= < > !== !=")).toEqual([
+      { type: "OPERATOR", value: ">=" },
+      { type: "OPERATOR", value: "<=" },
+      { type: "OPERATOR", value: "<" },
+      { type: "OPERATOR", value: ">" },
+      { type: "OPERATOR", value: "!==" },
+      { type: "OPERATOR", value: "!=" }
+    ]);
+  });
+
+  test("strings", () => {
+    expect(() => tokenize("'")).toThrow("Invalid expression");
+    expect(() => tokenize("'\\")).toThrow("Invalid expression");
+    expect(() => tokenize("'\\'")).toThrow("Invalid expression");
+    expect(tokenize("'hello ged'")).toEqual([{ type: "VALUE", value: "'hello ged'" }]);
+    expect(tokenize("'hello \\'ged\\''")).toEqual([{ type: "VALUE", value: "'hello \\'ged\\''" }]);
+
+    expect(() => tokenize('"')).toThrow("Invalid expression");
+    expect(() => tokenize('"\\"')).toThrow("Invalid expression");
+    expect(tokenize('"hello ged"')).toEqual([{ type: "VALUE", value: '"hello ged"' }]);
+    expect(tokenize('"hello ged"}')).toEqual([
+      { type: "VALUE", value: '"hello ged"' },
+      { type: "RIGHT_BRACE", value: "}" }
+    ]);
+    expect(tokenize('"hello \\"ged\\""')).toEqual([{ type: "VALUE", value: '"hello \\"ged\\""' }]);
+  });
+});
+
+describe("expression evaluation", () => {
+  test("simple static values", () => {
+    expect(compileExpr("1", {})).toBe("1");
+    expect(compileExpr("1 ", {})).toBe("1");
+    expect(compileExpr("'some string#/, {' ", {})).toBe("'some string#/, {'");
+    expect(compileExpr("{ } ", {})).toBe("{}");
+    expect(compileExpr("{a: 1} ", {})).toBe("{a:1}");
+    expect(compileExpr("{a: 1, b: 2   } ", {})).toBe("{a:1,b:2}");
+    expect(compileExpr("[] ", {})).toBe("[]");
+    expect(compileExpr("[1] ", {})).toBe("[1]");
+    expect(compileExpr("['1', '2'] ", {})).toBe("['1','2']");
+    expect(compileExpr("['1', \"2\"] ", {})).toBe("['1',\"2\"]");
+  });
+
+  test("various types of 'words'", () => {
+    expect(compileExpr("true", {})).toBe("true");
+    expect(compileExpr("false", {})).toBe("false");
+    expect(compileExpr("debugger", {})).toBe("debugger");
+  });
+
+  test("parenthesis", () => {
+    expect(compileExpr("(1)", {})).toBe("(1)");
+    expect(compileExpr("a*(1 +3)", {})).toBe("context['a']*(1+3)");
+  });
+
+  test("objects and sub objects", () => {
+    expect(compileExpr("{a:{b:1}} ", {})).toBe("{a:{b:1}}");
+  });
+
+  test("replacing variables", () => {
+    expect(compileExpr("a", {})).toBe("context['a']");
+    expect(compileExpr("a", { a: { id: "_3", expr: "" } })).toBe("_3");
+  });
+
+  test("arrays and objects", () => {
+    expect(compileExpr("[{b:1}] ", {})).toBe("[{b:1}]");
+    expect(compileExpr("{a: []} ", {})).toBe("{a:[]}");
+    expect(compileExpr("[{b:1, c: [1, {d: {e: 3}} ]}] ", {})).toBe("[{b:1,c:[1,{d:{e:3}}]}]");
+  });
+
+  test("dot operator", () => {
+    expect(compileExpr("a.b", {})).toBe("context['a'].b");
+    expect(compileExpr("a.b.c", {})).toBe("context['a'].b.c");
+  });
+
+  test("various unary operators", () => {
+    expect(compileExpr("!flag", {})).toBe("!context['flag']");
+    expect(compileExpr("-3", {})).toBe("-3");
+    expect(compileExpr("-a", {})).toBe("-context['a']");
+  });
+
+  test("various binary operators", () => {
+    expect(compileExpr("color == 'black'", {})).toBe("context['color']=='black'");
+    expect(compileExpr("a || b", {})).toBe("context['a']||context['b']");
+    expect(compileExpr("color === 'black'", {})).toBe("context['color']==='black'");
+    expect(compileExpr("'li_'+item", {})).toBe("'li_'+context['item']");
+    expect(compileExpr("state.val > 1", {})).toBe("context['state'].val>1");
+  });
+
+  test("boolean operations", () => {
+    expect(compileExpr("a && b", {})).toBe("context['a']&&context['b']");
+  });
+
+  test("ternary operators", () => {
+    expect(compileExpr("a ? b: '2'", {})).toBe("context['a']?context['b']:'2'");
+    expect(compileExpr("a ? b: (c or '2') ", {})).toBe(
+      "context['a']?context['b']:(context['c']||'2')"
+    );
+    expect(compileExpr("a ? {test:c}: [1,u]", {})).toBe(
+      "context['a']?{test:context['c']}:[1,context['u']]"
+    );
+  });
+
+  test("word replacement", () => {
+    expect(compileExpr("a or b", {})).toBe("context['a']||context['b']");
+    expect(compileExpr("a and b", {})).toBe("context['a']&&context['b']");
+  });
+
+  test("function calls", () => {
+    expect(compileExpr("a()", {})).toBe("context['a']()");
+    expect(compileExpr("a(1)", {})).toBe("context['a'](1)");
+    expect(compileExpr("a(1,2)", {})).toBe("context['a'](1,2)");
+    expect(compileExpr("a(1,2,{a:[a]})", {})).toBe("context['a'](1,2,{a:[context['a']]})");
+    expect(compileExpr("'x'.toUpperCase()", {})).toBe("'x'.toUpperCase()");
+    expect(compileExpr("'x'.toUpperCase({a: 3})", {})).toBe("'x'.toUpperCase({a:3})");
+    expect(compileExpr("'x'.toUpperCase(a)", { a: { id: "_v5", expr: "" } })).toBe(
+      "'x'.toUpperCase(_v5)"
+    );
+    expect(compileExpr("'x'.toUpperCase({b: a})", { a: { id: "_v5", expr: "" } })).toBe(
+      "'x'.toUpperCase({b:_v5})"
+    );
+  });
+});

tests/utils.test.ts

@@ -1,10 +1,4 @@
-import {
-  escape,
-  memoize,
-  debounce,
-  patch,
-  unpatch
-} from "../src/utils";
+import { escape, debounce } from "../src/utils";
 
 describe("escape", () => {
   test("normal strings", () => {
@@ -18,26 +12,6 @@ describe("escape", () => {
   });
 });
 
-describe("memoize", () => {
-  test("return correct value", () => {
-    const f = memoize((a, b) => a + b);
-    expect(f(1, 3)).toBe(4);
-  });
-
-  test("does not recompute if not needed", () => {
-    let nCalls = 0;
-    function origFunction(a: number, b: number): number {
-      nCalls++;
-      return a + b;
-    }
-    const memoized = memoize(origFunction);
-
-    expect(memoized(1, 3)).toBe(4);
-    expect(memoized(1, 3)).toBe(4);
-    expect(nCalls).toBe(1);
-  });
-});
-
 describe("debounce", () => {
   test("works as expected", () => {
     jest.useFakeTimers();
@@ -54,56 +28,3 @@ describe("debounce", () => {
     expect(n).toBe(1);
   });
 });
-
-describe("patch/unpatch", () => {
-  test("can monkey patch a class", () => {
-    class Test {
-      n = 1;
-
-      doSomething(): string {
-        return "hey";
-      }
-    }
-
-    patch(Test, "some_custo", {
-      doSomething(): string {
-        this.n = this.n + 1;
-        return this._super();
-      }
-    });
-
-    const t = new Test();
-    expect(t.n).toBe(1);
-    expect(t.doSomething()).toBe("hey");
-    expect(t.n).toBe(2);
-  });
-
-  test("cannot patch a class twice with same patch name", () => {
-    class Test {}
-
-    patch(Test, "some_custo", {});
-    expect(() => {
-      patch(Test, "some_custo", {});
-    }).toThrow();
-  });
-
-  test("can unpatch a class", () => {
-    class Test {
-      doSomething(): number {
-        return 1;
-      }
-    }
-
-    patch(Test, "some_custo", {
-      doSomething(): number {
-        return this._super() + 2;
-      }
-    });
-
-    const t = new Test();
-    expect(t.doSomething()).toBe(3);
-
-    unpatch(Test, "some_custo");
-    expect(t.doSomething()).toBe(1);
-  });
-});

tests/vdom.test.ts

@@ -59,9 +59,7 @@ describe("attributes", function() {
   test("are set correctly when namespaced", function() {
     const vnode1 = h("div", { attrs: { "xlink:href": "#foo" } });
     elm = patch(vnode0, vnode1).elm;
-    expect(elm.getAttributeNS("http://www.w3.org/1999/xlink", "href")).toBe(
-      "#foo"
-    );
+    expect(elm.getAttributeNS("http://www.w3.org/1999/xlink", "href")).toBe("#foo");
   });
 
   test("should not touch class nor id fields", function() {
@@ -207,12 +205,8 @@ describe("snabbdom", function() {
       expect(elm.firstChild.namespaceURI).toBe(SVGNamespace);
 
       // verify that svg tag automatically gets svg namespace
-      elm = patch(
-        vnode0,
-        h("svg", [
-          h("foreignObject", [h("div", ["I am HTML embedded in SVG"])])
-        ])
-      ).elm;
+      elm = patch(vnode0, h("svg", [h("foreignObject", [h("div", ["I am HTML embedded in SVG"])])]))
+        .elm;
       expect(elm.namespaceURI).toBe(SVGNamespace);
       expect(elm.firstChild.namespaceURI).toBe(SVGNamespace);
       expect(elm.firstChild.firstChild.namespaceURI).toBe(XHTMLNamespace);
@@ -352,13 +346,7 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(2);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("add elements in the middle", function() {
@@ -368,13 +356,7 @@ describe("snabbdom", function() {
         expect(elm.children.length).toBe(4);
         expect(elm.children.length).toBe(4);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("add elements at beginning and end", function() {
@@ -383,13 +365,7 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(3);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "1",
-          "2",
-          "3",
-          "4",
-          "5"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2", "3", "4", "5"]);
       });
 
       test("adds children to parent with no children", function() {
@@ -588,35 +564,19 @@ describe("snabbdom", function() {
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(6);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "4",
-          "3",
-          "2",
-          "1",
-          "5",
-          "0"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["4", "3", "2", "1", "5", "0"]);
       });
 
       test("supports null/undefined children", function() {
         const vnode1 = h("i", [0, 1, 2, 3, 4, 5].map(spanNum));
         const vnode2 = h(
           "i",
-          [null, 2, undefined, null, 1, 0, null, 5, 4, null, 3, undefined].map(
-            spanNum
-          )
+          [null, 2, undefined, null, 1, 0, null, 5, 4, null, 3, undefined].map(spanNum)
         );
         elm = patch(vnode0, vnode1).elm;
         expect(elm.children.length).toBe(6);
         elm = patch(vnode1, vnode2).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "2",
-          "1",
-          "0",
-          "5",
-          "4",
-          "3"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["2", "1", "0", "5", "4", "3"]);
       });
 
       test("supports all null/undefined children", function() {
@@ -627,14 +587,7 @@ describe("snabbdom", function() {
         elm = patch(vnode1, vnode2).elm;
         expect(elm.children.length).toBe(0);
         elm = patch(vnode2, vnode3).elm;
-        expect(map(elm.children, c => c.innerHTML)).toEqual([
-          "5",
-          "4",
-          "3",
-          "2",
-          "1",
-          "0"
-        ]);
+        expect(map(elm.children, c => c.innerHTML)).toEqual(["5", "4", "3", "2", "1", "0"]);
       });
     });
   });
@@ -714,18 +667,10 @@ describe("snabbdom", function() {
     });
 
     test("removes elements", function() {
-      const vnode1 = h("div", [
-        h("span", "One"),
-        h("span", "Two"),
-        h("span", "Three")
-      ]);
+      const vnode1 = h("div", [h("span", "One"), h("span", "Two"), h("span", "Three")]);
       const vnode2 = h("div", [h("span", "One"), h("span", "Three")]);
       elm = patch(vnode0, vnode1).elm;
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "One",
-        "Two",
-        "Three"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Two", "Three"]);
       elm = patch(vnode1, vnode2).elm;
       expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Three"]);
     });
@@ -760,49 +705,19 @@ describe("snabbdom", function() {
     });
 
     test("reorders elements", function() {
-      const vnode1 = h("div", [
-        h("span", "One"),
-        h("div", "Two"),
-        h("b", "Three")
-      ]);
-      const vnode2 = h("div", [
-        h("b", "Three"),
-        h("span", "One"),
-        h("div", "Two")
-      ]);
+      const vnode1 = h("div", [h("span", "One"), h("div", "Two"), h("b", "Three")]);
+      const vnode2 = h("div", [h("b", "Three"), h("span", "One"), h("div", "Two")]);
       elm = patch(vnode0, vnode1).elm;
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "One",
-        "Two",
-        "Three"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["One", "Two", "Three"]);
       elm = patch(vnode1, vnode2).elm;
       expect(map(elm.children, c => c.tagName)).toEqual(["B", "SPAN", "DIV"]);
-      expect(map(elm.children, c => c.innerHTML)).toEqual([
-        "Three",
-        "One",
-        "Two"
-      ]);
+      expect(map(elm.children, c => c.innerHTML)).toEqual(["Three", "One", "Two"]);
     });
 
     test("supports null/undefined children", function() {
       const vnode1 = h("i", [null, h("i", "1"), h("i", "2"), null]);
-      const vnode2 = h("i", [
-        h("i", "2"),
-        undefined,
-        undefined,
-        h("i", "1"),
-        undefined
-      ]);
-      const vnode3 = h("i", [
-        null,
-        h("i", "1"),
-        undefined,
-        null,
-        h("i", "2"),
-        undefined,
-        null
-      ]);
+      const vnode2 = h("i", [h("i", "2"), undefined, undefined, h("i", "1"), undefined]);
+      const vnode3 = h("i", [null, h("i", "1"), undefined, null, h("i", "2"), undefined, null]);
       elm = patch(vnode0, vnode1).elm;
       expect(map(elm.children, c => c.innerHTML)).toEqual(["1", "2"]);
       elm = patch(vnode1, vnode2).elm;
@@ -835,10 +750,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { create: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ]),
+          h("div", { hook: { create: cb } }, [h("span", "Child 1"), h("span", "Child 2")]),
           h("span", "Can't touch me")
         ]);
         patch(vnode0, vnode1);
@@ -855,10 +767,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { insert: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ]),
+          h("div", { hook: { insert: cb } }, [h("span", "Child 1"), h("span", "Child 2")]),
           h("span", "Can touch me")
         ]);
         patch(vnode0, vnode1);
@@ -874,17 +783,11 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { prepatch: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { prepatch: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { prepatch: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { prepatch: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -965,10 +868,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", { hook: { remove: cb } }, [
-            h("span", "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", { hook: { remove: cb } }, [h("span", "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div", [h("span", "First sibling")]);
         patch(vnode0, vnode1);
@@ -981,9 +881,7 @@ describe("snabbdom", function() {
         function cb(vnode) {
           calls++;
         }
-        const vnode1 = h("div", [
-          h("div", { hook: { destroy: cb } }, [h("span", "Child 1")])
-        ]);
+        const vnode1 = h("div", [h("div", { hook: { destroy: cb } }, [h("span", "Child 1")])]);
         const vnode2 = h("div", "Text node");
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1053,10 +951,7 @@ describe("snabbdom", function() {
           result.push(vnode);
           rm();
         }
-        const vnode1 = h("div", { hook: { remove: cb } }, [
-          h("b", "Child 1"),
-          h("i", "Child 2")
-        ]);
+        const vnode1 = h("div", { hook: { remove: cb } }, [h("b", "Child 1"), h("i", "Child 2")]);
         const vnode2 = h("span", [h("b", "Child 1"), h("i", "Child 2")]);
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1091,10 +986,7 @@ describe("snabbdom", function() {
         }
         const vnode1 = h("div", [
           h("span", "First sibling"),
-          h("div", [
-            h("span", { hook: { destroy: cb } }, "Child 1"),
-            h("span", "Child 2")
-          ])
+          h("div", [h("span", { hook: { destroy: cb } }, "Child 1"), h("span", "Child 2")])
         ]);
         const vnode2 = h("div");
         patch(vnode0, vnode1);
@@ -1150,11 +1042,7 @@ describe("snabbdom", function() {
             }
           }
         ]);
-        const vnode1 = h("div", [
-          h("span", "First child"),
-          "",
-          h("span", "Third child")
-        ]);
+        const vnode1 = h("div", [h("span", "First child"), "", h("span", "Third child")]);
         const vnode2 = h("div");
         patch(vnode0, vnode1);
         patch(vnode1, vnode2);
@@ -1196,10 +1084,7 @@ describe("snabbdom", function() {
       function cb(vnode) {
         result.push(vnode);
       }
-      const vnode1 = h("div", [
-        h("span", { hook: { update: cb } }, "Hello"),
-        h("span", "there")
-      ]);
+      const vnode1 = h("div", [h("span", { hook: { update: cb } }, "Hello"), h("span", "there")]);
       patch(vnode0, vnode1);
       patch(vnode1, vnode1);
       expect(result).toHaveLength(0);

tools/benchmarks/odoo-widgets-12.0/app.js

@@ -1,4 +1,9 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
 
 odoo.define("app", function(require) {
   const Widget = require("web.Widget");
@@ -97,14 +102,23 @@ odoo.define("app", function(require) {
       "click .o_btn_msg.10000": function() {
         this.addMessages(10000);
       },
-      "click .o_btn_msg.50000": function() {
-        this.addMessages(50000);
+      "click .o_btn_msg.30000": function() {
+        this.addMessages(30000);
       },
       "click .updateSomeMessages": function() {
         this.updateSomeMessages();
       },
       "click .clear": function() {
         this.clear();
+      },
+      "click .o_multiple": function() {
+        this.multipleFlag = !this.multipleFlag;
+      },
+      "click .o_clear": function() {
+        this.clearFlag = !this.clearFlag;
+      },
+      "click .clear-log": function() {
+        this.$log[0].innerHTML = "";
       }
     },
     custom_events: {
@@ -116,11 +130,15 @@ odoo.define("app", function(require) {
       this.widgets = {};
       this.isInDom = false;
       this.messageCount = 0;
+      this.multipleFlag = false;
+      this.clearFlag = false;
     },
 
     start: function() {
       this.$content = this.$(".content");
       this.$msgCount = this.$(".message_count");
+      this.$log = this.$(".log-content");
+      this.log("Benchmarking odoo widgets, 12.0");
     },
     on_attach_callback: function() {
       this.isInDom = true;
@@ -144,34 +162,41 @@ odoo.define("app", function(require) {
     },
 
     addMessages: function(n) {
-      var self = this;
-      startMeasure("add " + n);
-      const defs = [];
-      const messages = buildData(n);
-      for (let message of messages) {
-        const widget = new Message(this, message);
-        this.widgets[message.id] = widget;
-        defs.push(widget.appendTo("<div>"));
-      }
-      $.when
-        .apply($, defs)
-        .then(function() {
-          for (let message of messages) {
-            let widget = self.widgets[message.id];
-            dom.append(self.$content, widget.$el, {
-              in_DOM: this.isInDom,
-              callbacks: [{ widget: widget }]
-            });
-          }
-        })
-        .then(function() {
-          self.messageCount += n;
-          self.updateMessageCount();
-          stopMeasure();
-        });
+      const self = this;
+      this.benchmark("add " + n, () => {
+        const defs = [];
+        const messages = buildData(n);
+        for (let message of messages) {
+          const widget = new Message(this, message);
+          this.widgets[message.id] = widget;
+          defs.push(widget.appendTo("<div>"));
+        }
+        return $.when
+          .apply($, defs)
+          .then(function() {
+            for (let message of messages) {
+              let widget = self.widgets[message.id];
+              dom.append(self.$content, widget.$el, {
+                in_DOM: this.isInDom,
+                callbacks: [{ widget: widget }]
+              });
+            }
+          })
+          .then(function() {
+            self.messageCount += n;
+            self.updateMessageCount();
+          });
+      });
     },
     clear: function() {
       startMeasure("clear");
+      this._clear();
+      stopMeasure(info => {
+        this.log(info.msg);
+      });
+    },
+
+    _clear: function() {
       this.$content.empty();
       for (let key in this.widgets) {
         this.widgets[key].destroy();
@@ -179,15 +204,14 @@ odoo.define("app", function(require) {
       }
       this.messageCount = 0;
       this.updateMessageCount();
-      stopMeasure();
     },
     updateSomeMessages: function() {
-      startMeasure("update every 10th");
-      const widgets = Object.values(this.widgets);
-      for (let i = 0; i < widgets.length; i += 10) {
-        widgets[i].update();
-      }
-      stopMeasure();
+      this.benchmark("update every 10th", () => {
+        const widgets = Object.values(this.widgets);
+        for (let i = 0; i < widgets.length; i += 10) {
+          widgets[i].update();
+        }
+      });
     },
     _onRemoveMessage: function(ev) {
       startMeasure("remove message");
@@ -196,6 +220,65 @@ odoo.define("app", function(require) {
       this.messageCount--;
       this.updateMessageCount();
       stopMeasure();
+    },
+
+    benchmark: function(message, fn, callback) {
+      if (this.multipleFlag) {
+        const N = 20;
+        let n = N;
+        let total = 0;
+        let cb = info => {
+          let finalize = () => {
+            n--;
+            total += info.delta;
+            if (n === 0) {
+              const avg = total / N;
+              this.log(`Average: ${formatNumber(avg)}ms`, true);
+              if (callback) {
+                callback();
+              }
+            } else {
+              this._benchmark(message, fn, cb);
+            }
+          };
+
+          if (this.clearFlag) {
+            this._benchmark("clear", this._clear.bind(this), finalize, false);
+          } else {
+            finalize();
+          }
+        };
+        this._benchmark(message, fn, cb);
+      } else {
+        this._benchmark(message, fn, callback);
+      }
+    },
+
+    _benchmark: function(message, fn, cb, log = true) {
+      setTimeout(() => {
+        startMeasure(message);
+        const benchmark = fn();
+        (benchmark && benchmark.then ? benchmark : $.when()).then(() => {
+          stopMeasure(info => {
+            if (log) {
+              this.log(info.msg);
+            }
+            if (cb) {
+              cb(info);
+            }
+          });
+        }, 10);
+      });
+    },
+
+    log: function(str, isBold) {
+      const div = document.createElement("div");
+      if (isBold) {
+        div.classList.add("bold");
+      }
+      div.textContent = `> ${str}`;
+      this.$log[0].appendChild(div);
+      this.$log[0].scrollTop = this.$log[0].scrollHeight;
     }
   });
 

tools/benchmarks/odoo-widgets-12.0/templates.xml

@@ -0,0 +1,47 @@
+<templates>
+    <div class="main" t-name="root">
+        <div class="left-thing">
+            <div class="title">Actions</div>
+            <div class="panel">
+                <button class="o_btn_msg 100">Add 100 messages</button>
+                <button class="o_btn_msg 1000">Add 1k messages</button>
+                <button class="o_btn_msg 10000">Add 10k messages</button>
+                <button class="o_btn_msg 30000">Add 30k messages</button>
+                <button class="updateSomeMessages">Update every 10th message</button>
+                <button class="clear">Clear</button>
+            </div>
+            <div class="flags">
+                <div>
+                    <input type="checkbox" class="o_multiple" id="multipleflag" />
+                    <label for="multipleflag">Do it 20x</label>
+                </div>
+                <div>
+                    <input type="checkbox" class="o_clear" id="clearFlag" />
+                    <label for="clearFlag">Clear after</label>
+                </div>
+            </div>
+            <div class="info message_count">
+                Number of messages: 0
+            </div>
+            <div class="title">Log <span class="clear-log">(clear)</span></div>
+            <div class="log">
+                <div class="log-content"/>
+            </div>
+        </div>
+        <div class="right-thing">
+            <div class="content">
+            </div>
+        </div>
+    </div>
+
+    <div t-name="message" class="message">
+        <span class="author"><t t-esc="widget.author"/></span>
+        <span class="msg"><t t-esc="widget.msg"/></span>
+        <button class="remove">Remove</button>
+    </div>
+
+  <div t-name="counter">
+    <button class="o_increment"></button>
+  </div>
+
+</templates>

tools/benchmarks/odoo-widgets-12.3/app.js

@@ -1,4 +1,9 @@
-import { buildData, startMeasure, stopMeasure } from "../shared/utils.js";
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
 
 odoo.define("app", function(require) {
   const Widget = require("web.Widget");
@@ -97,14 +102,23 @@ odoo.define("app", function(require) {
       "click .o_btn_msg.10000": function() {
         this.addMessages(10000);
       },
-      "click .o_btn_msg.50000": function() {
-        this.addMessages(50000);
+      "click .o_btn_msg.30000": function() {
+        this.addMessages(30000);
       },
       "click .updateSomeMessages": function() {
         this.updateSomeMessages();
       },
       "click .clear": function() {
         this.clear();
+      },
+      "click .o_multiple": function() {
+        this.multipleFlag = !this.multipleFlag;
+      },
+      "click .o_clear": function() {
+        this.clearFlag = !this.clearFlag;
+      },
+      "click .clear-log": function() {
+        this.$log[0].innerHTML = "";
       }
     },
     custom_events: {
@@ -116,11 +130,15 @@ odoo.define("app", function(require) {
       this.widgets = {};
       this.isInDom = false;
       this.messageCount = 0;
+      this.multipleFlag = false;
+      this.clearFlag = false;
     },
 
     start: function() {
       this.$content = this.$(".content");
       this.$msgCount = this.$(".message_count");
+      this.$log = this.$(".log-content");
+      this.log("Benchmarking odoo widgets, 12.3");
     },
     on_attach_callback: function() {
       this.isInDom = true;
@@ -144,34 +162,41 @@ odoo.define("app", function(require) {
     },
 
     addMessages: function(n) {
-      var self = this;
-      startMeasure("add " + n);
-      const defs = [];
-      const messages = buildData(n);
-      for (let message of messages) {
-        const widget = new Message(this, message);
-        this.widgets[message.id] = widget;
-        defs.push(widget.appendTo("<div>"));
-      }
-      $.when
-        .apply($, defs)
-        .then(function() {
-          for (let message of messages) {
-            let widget = self.widgets[message.id];
-            dom.append(self.$content, widget.$el, {
-              in_DOM: this.isInDom,
-              callbacks: [{ widget: widget }]
-            });
-          }
-        })
-        .then(function() {
-          self.messageCount += n;
-          self.updateMessageCount();
-          stopMeasure();
-        });
+      const self = this;
+      this.benchmark("add " + n, () => {
+        const defs = [];
+        const messages = buildData(n);
+        for (let message of messages) {
+          const widget = new Message(this, message);
+          this.widgets[message.id] = widget;
+          defs.push(widget.appendTo("<div>"));
+        }
+        return $.when
+          .apply($, defs)
+          .then(function() {
+            for (let message of messages) {
+              let widget = self.widgets[message.id];
+              dom.append(self.$content, widget.$el, {
+                in_DOM: this.isInDom,
+                callbacks: [{ widget: widget }]
+              });
+            }
+          })
+          .then(function() {
+            self.messageCount += n;
+            self.updateMessageCount();
+          });
+      });
     },
     clear: function() {
       startMeasure("clear");
+      this._clear();
+      stopMeasure(info => {
+        this.log(info.msg);
+      });
+    },
+
+    _clear: function() {
       this.$content.empty();
       for (let key in this.widgets) {
         this.widgets[key].destroy();
@@ -179,15 +204,14 @@ odoo.define("app", function(require) {
       }
       this.messageCount = 0;
       this.updateMessageCount();
-      stopMeasure();
     },
     updateSomeMessages: function() {
-      startMeasure("update every 10th");
-      const widgets = Object.values(this.widgets);
-      for (let i = 0; i < widgets.length; i += 10) {
-        widgets[i].update();
-      }
-      stopMeasure();
+      this.benchmark("update every 10th", () => {
+        const widgets = Object.values(this.widgets);
+        for (let i = 0; i < widgets.length; i += 10) {
+          widgets[i].update();
+        }
+      });
     },
     _onRemoveMessage: function(ev) {
       startMeasure("remove message");
@@ -196,6 +220,65 @@ odoo.define("app", function(require) {
       this.messageCount--;
       this.updateMessageCount();
       stopMeasure();
+    },
+
+    benchmark: function(message, fn, callback) {
+      if (this.multipleFlag) {
+        const N = 20;
+        let n = N;
+        let total = 0;
+        let cb = info => {
+          let finalize = () => {
+            n--;
+            total += info.delta;
+            if (n === 0) {
+              const avg = total / N;
+              this.log(`Average: ${formatNumber(avg)}ms`, true);
+              if (callback) {
+                callback();
+              }
+            } else {
+              this._benchmark(message, fn, cb);
+            }
+          };
+
+          if (this.clearFlag) {
+            this._benchmark("clear", this._clear.bind(this), finalize, false);
+          } else {
+            finalize();
+          }
+        };
+        this._benchmark(message, fn, cb);
+      } else {
+        this._benchmark(message, fn, callback);
+      }
+    },
+
+    _benchmark: function(message, fn, cb, log = true) {
+      setTimeout(() => {
+        startMeasure(message);
+        const benchmark = fn();
+        (benchmark && benchmark.then ? benchmark : $.when()).then(() => {
+          stopMeasure(info => {
+            if (log) {
+              this.log(info.msg);
+            }
+            if (cb) {
+              cb(info);
+            }
+          });
+        }, 10);
+      });
+    },
+
+    log: function(str, isBold) {
+      const div = document.createElement("div");
+      if (isBold) {
+        div.classList.add("bold");
+      }
+      div.textContent = `> ${str}`;
+      this.$log[0].appendChild(div);
+      this.$log[0].scrollTop = this.$log[0].scrollHeight;
     }
   });
 

tools/benchmarks/odoo-widgets-12.3/templates.xml

@@ -0,0 +1,47 @@
+<templates>
+    <div class="main" t-name="root">
+        <div class="left-thing">
+            <div class="title">Actions</div>
+            <div class="panel">
+                <button class="o_btn_msg 100">Add 100 messages</button>
+                <button class="o_btn_msg 1000">Add 1k messages</button>
+                <button class="o_btn_msg 10000">Add 10k messages</button>
+                <button class="o_btn_msg 30000">Add 30k messages</button>
+                <button class="updateSomeMessages">Update every 10th message</button>
+                <button class="clear">Clear</button>
+            </div>
+            <div class="flags">
+                <div>
+                    <input type="checkbox" class="o_multiple" id="multipleflag" />
+                    <label for="multipleflag">Do it 20x</label>
+                </div>
+                <div>
+                    <input type="checkbox" class="o_clear" id="clearFlag" />
+                    <label for="clearFlag">Clear after</label>
+                </div>
+            </div>
+            <div class="info message_count">
+                Number of messages: 0
+            </div>
+            <div class="title">Log <span class="clear-log">(clear)</span></div>
+            <div class="log">
+                <div class="log-content"/>
+            </div>
+        </div>
+        <div class="right-thing">
+            <div class="content">
+            </div>
+        </div>
+    </div>
+
+    <div t-name="message" class="message">
+        <span class="author"><t t-esc="widget.author"/></span>
+        <span class="msg"><t t-esc="widget.msg"/></span>
+        <button class="remove">Remove</button>
+    </div>
+
+  <div t-name="counter">
+    <button class="o_increment"></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.10.0/app.js

@@ -0,0 +1,173 @@
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+  template = "Counter";
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+  template = "Message";
+
+  shouldUpdate(nextProps) {
+    return nextProps !== this.props;
+  }
+  removeMessage() {
+    this.trigger("remove_message", {
+      id: this.props.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+  template = "App";
+
+  mounted() {
+    this.log(
+      `Benchmarking Owl v${owl._version} (build date: ${
+        owl._date
+      })`
+    );
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(data) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === data.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.10.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.10.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.10.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="'log'"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.author"/></span>
+    <span class="msg"><t t-esc="props.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <t t-widget="Counter"/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.11.0/app.js

@@ -0,0 +1,170 @@
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps !== this.props;
+  }
+  removeMessage() {
+    this.trigger("remove_message", {
+      id: this.props.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(
+      `Benchmarking Owl v${owl._version} (build date: ${
+        owl._date
+      })`
+    );
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(data) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === data.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.11.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.11.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.11.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="'log'"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.author"/></span>
+    <span class="msg"><t t-esc="props.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <t t-widget="Counter"/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.12.0/app.js

@@ -0,0 +1,170 @@
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+
+  shouldUpdate(nextProps) {
+    return nextProps !== this.props;
+  }
+  removeMessage() {
+    this.trigger("remove_message", {
+      id: this.props.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+
+  mounted() {
+    this.log(
+      `Benchmarking Owl v${owl.__info__.version} (build date: ${
+        owl.__info__.date
+      })`
+    );
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this.benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(data) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === data.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.12.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.12.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.12.0/templates.xml

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

tools/benchmarks/owl-0.13.0/app.js

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

tools/benchmarks/owl-0.13.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.13.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.13.0/templates.xml

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

tools/benchmarks/owl-0.14.0/app.js

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

tools/benchmarks/owl-0.14.0/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>OWL 0.14.0 Benchmark</title>
+  <link href="../shared/main.css" rel="stylesheet"/>
+  <script src='owl.js'></script>
+</head>
+<body>
+  <div id='main'></div>
+  <script src='app.js' type="module"></script>
+</body>
+</html>

tools/benchmarks/owl-0.14.0/templates.xml

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

tools/benchmarks/owl-0.15.0/app.js

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

tools/benchmarks/owl-0.15.0/index.html

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

tools/benchmarks/owl-0.15.0/templates.xml

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

tools/benchmarks/owl-0.7.0/app.js

@@ -0,0 +1,173 @@
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+  template = "Counter";
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+  template = "Message";
+
+  shouldUpdate(nextProps) {
+    return nextProps !== this.props;
+  }
+  removeMessage() {
+    this.trigger("remove_message", {
+      id: this.props.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+  template = "App";
+
+  mounted() {
+    this.log(
+      `Benchmarking Owl v${owl._version} (build date: ${
+        owl._date
+      })`
+    );
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(data) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === data.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.7.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="'log'"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.author"/></span>
+    <span class="msg"><t t-esc="props.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <t t-widget="Counter"/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>

tools/benchmarks/owl-0.8.0/app.js

@@ -0,0 +1,173 @@
+import {
+  buildData,
+  startMeasure,
+  stopMeasure,
+  formatNumber
+} from "../shared/utils.js";
+
+//------------------------------------------------------------------------------
+// Likes Counter Widget
+//------------------------------------------------------------------------------
+class Counter extends owl.Component {
+  state = { counter: 0 };
+  template = "Counter";
+
+  increment() {
+    this.state.counter++;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Message Widget
+//------------------------------------------------------------------------------
+class Message extends owl.Component {
+  widgets = { Counter };
+  template = "Message";
+
+  shouldUpdate(nextProps) {
+    return nextProps !== this.props;
+  }
+  removeMessage() {
+    this.trigger("remove_message", {
+      id: this.props.id
+    });
+  }
+}
+
+//------------------------------------------------------------------------------
+// Root Widget
+//------------------------------------------------------------------------------
+class App extends owl.Component {
+  widgets = { Message };
+  state = { messages: [], multipleFlag: false, clearAfterFlag: false };
+  template = "App";
+
+  mounted() {
+    this.log(
+      `Benchmarking Owl v${owl._version} (build date: ${
+        owl._date
+      })`
+    );
+  }
+
+  benchmark(message, fn, callback) {
+    if (this.state.multipleFlag) {
+      const N = 20;
+      let n = N;
+      let total = 0;
+      let cb = info => {
+        let finalize = () => {
+          n--;
+          total += info.delta;
+          if (n === 0) {
+            const avg = total / N;
+            this.log(`Average: ${formatNumber(avg)}ms`, true);
+            if (callback) {
+              callback();
+            }
+          } else {
+            this._benchmark(message, fn, cb);
+          }
+        };
+
+        if (this.state.clearAfterFlag) {
+          this._benchmark(
+            "clear",
+            () => {
+              this.state.messages = [];
+            },
+            finalize,
+            false
+          );
+        } else {
+          finalize();
+        }
+      };
+      this._benchmark(message, fn, cb);
+    } else {
+      this._benchmark(message, fn, callback);
+    }
+  }
+
+  _benchmark(message, fn, cb, log = true) {
+    setTimeout(() => {
+      startMeasure(message);
+      fn();
+      stopMeasure(info => {
+        if (log) {
+          this.log(info.msg);
+        }
+        if (cb) {
+          cb(info);
+        }
+      });
+    }, 10);
+  }
+
+  addMessages(n) {
+    this.benchmark("add " + n, () => {
+      const newMessages = buildData(n);
+      this.state.messages.push.apply(this.state.messages, newMessages);
+    });
+  }
+
+  clear() {
+    this._benchmark("clear", () => {
+      this.state.messages = [];
+    });
+  }
+
+  updateSomeMessages() {
+    this.benchmark("update every 10th", () => {
+      const messages = this.state.messages;
+      for (let i = 0; i < this.state.messages.length; i += 10) {
+        const msg = Object.assign({}, messages[i]);
+        msg.author += "!!!";
+        this.set(messages, i, msg);
+      }
+    });
+  }
+
+  removeMessage(data) {
+    this.benchmark("remove message", () => {
+      const index = this.state.messages.findIndex(m => m.id === data.id);
+      this.state.messages.splice(index, 1);
+    });
+  }
+
+  log(str, isBold) {
+    const div = document.createElement("div");
+    if (isBold) {
+      div.classList.add("bold");
+    }
+    div.textContent = `> ${str}`;
+    this.refs.log.appendChild(div);
+    this.refs.log.scrollTop = this.refs.log.scrollHeight;
+  }
+
+  clearLog() {
+    this.refs.log.innerHTML = "";
+  }
+
+  toggleMultiple() {
+    this.state.multipleFlag = !this.state.multipleFlag;
+  }
+
+  toggleClear() {
+    this.state.clearAfterFlag = !this.state.clearAfterFlag;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Application initialization
+//------------------------------------------------------------------------------
+async function start() {
+  const templates = await owl.utils.loadTemplates("templates.xml");
+  const env = {
+    qweb: new owl.QWeb(templates)
+  };
+  const app = new App(env);
+  app.mount(document.body);
+}
+
+start();

tools/benchmarks/owl-0.8.0/templates.xml

@@ -0,0 +1,50 @@
+<templates>
+  <div t-name="App" class="main">
+      <div class="left-thing">
+        <div class="title">Actions</div>
+        <div class="panel">
+          <button t-on-click="addMessages(100)">Add 100 messages</button>
+          <button t-on-click="addMessages(1000)">Add 1k messages</button>
+          <button t-on-click="addMessages(10000)">Add 10k messages</button>
+          <button t-on-click="addMessages(30000)">Add 30k messages</button>
+          <button t-on-click="updateSomeMessages">Update every 10th messages</button>
+          <button t-on-click="clear">Clear</button>
+        </div>
+        <div class="flags">
+            <div>
+                <input type="checkbox" id="multipleflag" t-on-change="toggleMultiple" t-att-checked="state.multipleFlag"/>
+                <label for="multipleflag">Do it 20x</label>
+            </div>
+            <div>
+                <input type="checkbox" id="clearFlag" t-on-change="toggleClear"  t-att-checked="state.clearAfterFlag"/>
+                <label for="clearFlag">Clear after</label>
+            </div>
+        </div>
+        <div class="info">Number of messages: <t t-esc="state.messages.length"/></div>
+        <hr/>
+        <div class="title">Log <span class="clear-log" t-on-click="clearLog">(clear)</span></div>
+        <div class="log">
+            <div class="log-content" t-ref="'log'"/>
+        </div>
+      </div>
+      <div class="right-thing">
+          <div class="content" t-on-remove-message="removeMessage">
+              <t t-foreach="state.messages" t-as="message">
+                  <t t-widget="Message" t-key="message.id" t-props="message" t-on-remove_message="removeMessage"/>
+              </t>
+          </div>
+      </div>
+  </div>
+
+  <div t-name="Message" class="message">
+    <span class="author"><t t-esc="props.author"/></span>
+    <span class="msg"><t t-esc="props.msg"/></span>
+    <button class="remove" t-on-click="removeMessage">Remove</button>
+    <t t-widget="Counter"/>
+  </div>
+
+  <div t-name="Counter">
+    <button t-on-click="increment">Value: <t t-esc="state.counter"/></button>
+  </div>
+
+</templates>