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2 changes: 1 addition & 1 deletion docs/docs/07-working-with-the-browser.md
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Expand Up @@ -10,7 +10,7 @@ next: more-about-refs.html
React provides powerful abstractions that free you from touching the DOM directly in most cases, but sometimes you simply need to access the underlying API, perhaps to work with a third-party library or existing code.


## The Mock DOM
## The Virtual DOM

React is so fast because it never talks to the DOM directly. React maintains a fast in-memory representation of the DOM. `render()` methods return a *description* of the DOM, and React can diff this description with the in-memory representation to compute the fastest way to update the browser.

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4 changes: 0 additions & 4 deletions docs/docs/08-tooling-integration.md
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Expand Up @@ -55,7 +55,3 @@ The open-source community has built tools that integrate JSX with several build
that support `*.tmLanguage`.
* Linting provides accurate line numbers after compiling without sourcemaps.
* Elements use standard scoping so linters can find usage of out-of-scope components.

## React Page

To get started on a new project, you can use [react-page](https://github.com/facebook/react-page/), a complete React project creator. It supports both server-side and client-side rendering, source transform and packaging JSX files using CommonJS modules, and instant reload.
2 changes: 1 addition & 1 deletion docs/docs/09.1-animation.md
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Expand Up @@ -35,7 +35,7 @@ var TodoList = React.createClass({
render: function() {
var items = this.state.items.map(function(item, i) {
return (
<div key={i} onClick={this.handleRemove.bind(this, i)}>
<div key={item} onClick={this.handleRemove.bind(this, i)}>
{item}
</div>
);
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1 change: 0 additions & 1 deletion docs/docs/10-examples.md
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Expand Up @@ -17,6 +17,5 @@ prev: class-name-manipulation.html

* We've included [a step-by-step comment box tutorial](/react/docs/tutorial.html).
* [The React starter kit](/react/downloads.html) includes several examples which you can [view online in our GitHub repository](https://github.com/facebook/react/tree/master/examples/).
* [React Page](https://github.com/facebook/react-page) is a simple React project creator to get you up-and-running quickly with React. It supports both server-side and client-side rendering, source transform and packaging JSX files using CommonJS modules, and instant reload.
* [React one-hour email](https://github.com/petehunt/react-one-hour-email/commits/master) goes step-by-step from a static HTML mock to an interactive email reader (written in just one hour!)
* [Rendr + React app template](https://github.com/petehunt/rendr-react-template/) demonstrates how to use React's server rendering capabilities.
2 changes: 1 addition & 1 deletion docs/docs/ref-01-top-level-api.md
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Expand Up @@ -46,7 +46,7 @@ ReactComponent renderComponent(
)
```

Render a React component into the DOM in the supplied `container`.
Render a React component into the DOM in the supplied `container` and return a reference to the component.

If the React component was previously rendered into `container`, this will perform an update on it and only mutate the DOM as necessary to reflect the latest React component.

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2 changes: 1 addition & 1 deletion docs/docs/ref-08-reconciliation.md
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Expand Up @@ -103,7 +103,7 @@ renderB: <div><span>second</span><span>first</span></div>
=> [replaceAttribute textContent 'second'], [insertNode <span>first</span>]
```

There are many algorithms that attempt to find the minimum sets of operations to transform a list of elements. [Levenshtein distance](http://en.wikipedia.org/wiki/Levenshtein_distance) can find the minimum using single element insertion, deletion and substitution in O(n<sup>2</sup>). Even if we were to use Levenshtein, this doesn't find when a node has moved into another position and algorithms to do that have a much worst complexity.
There are many algorithms that attempt to find the minimum sets of operations to transform a list of elements. [Levenshtein distance](http://en.wikipedia.org/wiki/Levenshtein_distance) can find the minimum using single element insertion, deletion and substitution in O(n<sup>2</sup>). Even if we were to use Levenshtein, this doesn't find when a node has moved into another position and algorithms to do that have much worse complexity.

### Keys

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31 changes: 31 additions & 0 deletions docs/tips/16-references-to-components.md
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@@ -0,0 +1,31 @@
---
id: references-to-components
title: References to Components
layout: tips
permalink: references-to-components.html
prev: expose-component-functions.html
---

If you're using React components in a larger non-React application or transitioning your code to React, you may need to keep references to components. `React.renderComponent` returns a reference to the mounted component:

```js
/** @jsx React.DOM */

var myComponent = React.renderComponent(<MyComponent />, myContainer);
```

If you pass a variable to 'React.renderComponent`, it's not guaranteed that the component passed in will be the one that's mounted. In cases where you construct a component before mounting it, be sure to reassign your variable:

```js
/** @jsx React.DOM */

var myComponent = <MyComponent />;

// Some code here...

myComponent = React.renderComponent(myComponent, myContainer);
```

> Note:
>
> This should only ever be used at the top level. Inside components, let your `props` and `state` handle communication with child components, and only reference components via `ref`s.
48 changes: 41 additions & 7 deletions src/core/ReactComponent.js
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Expand Up @@ -43,11 +43,15 @@ var ComponentLifeCycle = keyMirror({
});

/**
* Warn if there's no key explicitly set on dynamic arrays of children.
* This allows us to keep track of children between updates.
* Warn if there's no key explicitly set on dynamic arrays of children or
* object keys are not valid. This allows us to keep track of children between
* updates.
*/

var ownerHasWarned = {};
var ownerHasExplicitKeyWarning = {};
var ownerHasPropertyWarning = {};

var NUMERIC_PROPERTY_REGEX = /^\d+$/;

/**
* Warn if the component doesn't have an explicit key assigned to it.
Expand All @@ -71,10 +75,10 @@ function validateExplicitKey(component) {

// Name of the component whose render method tried to pass children.
var currentName = ReactCurrentOwner.current.constructor.displayName;
if (ownerHasWarned.hasOwnProperty(currentName)) {
if (ownerHasExplicitKeyWarning.hasOwnProperty(currentName)) {
return;
}
ownerHasWarned[currentName] = true;
ownerHasExplicitKeyWarning[currentName] = true;

var message = 'Each child in an array should have a unique "key" prop. ' +
'Check the render method of ' + currentName + '.';
Expand All @@ -95,8 +99,34 @@ function validateExplicitKey(component) {
}

/**
* Ensure that every component either is passed in a static location or, if
* if it's passed in an array, has an explicit key property defined.
* Warn if the key is being defined as an object property but has an incorrect
* value.
*
* @internal
* @param {string} name Property name of the key.
* @param {ReactComponent} component Component that requires a key.
*/
function validatePropertyKey(name) {
if (NUMERIC_PROPERTY_REGEX.test(name)) {
// Name of the component whose render method tried to pass children.
var currentName = ReactCurrentOwner.current.constructor.displayName;
if (ownerHasPropertyWarning.hasOwnProperty(currentName)) {
return;
}
ownerHasPropertyWarning[currentName] = true;

console.warn(
'Child objects should have non-numeric keys so ordering is preserved. ' +
'Check the render method of ' + currentName + '. ' +
'See http://fb.me/react-warning-keys for more information.'
);
}
}

/**
* Ensure that every component either is passed in a static location, in an
* array with an explicit keys property defined, or in an object literal
* with valid key property.
*
* @internal
* @param {*} component Statically passed child of any type.
Expand All @@ -113,6 +143,10 @@ function validateChildKeys(component) {
} else if (ReactComponent.isValidComponent(component)) {
// This component was passed in a valid location.
component.__keyValidated__ = true;
} else if (component && typeof component === 'object') {
for (var name in component) {
validatePropertyKey(name, component);
}
}
}

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2 changes: 2 additions & 0 deletions src/core/ReactPropTransferer.js
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Expand Up @@ -42,6 +42,8 @@ function createTransferStrategy(mergeStrategy) {

/**
* Transfer strategies dictate how props are transferred by `transferPropsTo`.
* NOTE: if you add any more exceptions to this list you should be sure to
* update `cloneWithProps()` accordingly.
*/
var TransferStrategies = {
/**
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4 changes: 4 additions & 0 deletions src/dom/DOMPropertyOperations.js
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Expand Up @@ -95,6 +95,10 @@ var DOMPropertyOperations = {
return '';
}
var attributeName = DOMProperty.getAttributeName[name];
console.log(attributeName);
if (value && DOMProperty.hasBooleanValue[name]) {
return escapeTextForBrowser(attributeName);
}
return processAttributeNameAndPrefix(attributeName) +
escapeTextForBrowser(value) + '"';
} else if (DOMProperty.isCustomAttribute(name)) {
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4 changes: 2 additions & 2 deletions src/dom/__tests__/DOMPropertyOperations-test.js
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Expand Up @@ -82,12 +82,12 @@ describe('DOMPropertyOperations', function() {
expect(DOMPropertyOperations.createMarkupForProperty(
'checked',
'simple'
)).toBe('checked="simple"');
)).toBe('checked');

expect(DOMPropertyOperations.createMarkupForProperty(
'checked',
true
)).toBe('checked="true"');
)).toBe('checked');

expect(DOMPropertyOperations.createMarkupForProperty(
'checked',
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13 changes: 10 additions & 3 deletions src/dom/components/ReactDOMInput.js
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Expand Up @@ -130,17 +130,24 @@ var ReactDOMInput = ReactCompositeComponent.createClass({
var name = this.props.name;
if (this.props.type === 'radio' && name != null) {
var rootNode = this.getDOMNode();
var queryRoot = rootNode;

while (queryRoot.parentNode) {
queryRoot = queryRoot.parentNode;
}

// If `rootNode.form` was non-null, then we could try `form.elements`,
// but that sometimes behaves strangely in IE8. We could also try using
// `form.getElementsByName`, but that will only return direct children
// and won't include inputs that use the HTML5 `form=` attribute. Since
// the input might not even be in a form, let's just use the global
// `getElementsByName` to ensure we don't miss anything.
var group = document.getElementsByName(name);
// `querySelectorAll` to ensure we don't miss anything.
var group = queryRoot.querySelectorAll(
'input[name=' + JSON.stringify('' + name) + '][type="radio"]');

for (var i = 0, groupLen = group.length; i < groupLen; i++) {
var otherNode = group[i];
if (otherNode === rootNode ||
otherNode.nodeName !== 'INPUT' || otherNode.type !== 'radio' ||
otherNode.form !== rootNode.form) {
continue;
}
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52 changes: 52 additions & 0 deletions src/utils/__tests__/cloneWithProps-test.js
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Expand Up @@ -126,4 +126,56 @@ describe('cloneWithProps', function() {
cloneWithProps(<Component />, {key: 'xyz'})
);
});

it('should transfer children', function() {
var Component = React.createClass({
render: function() {
expect(this.props.children).toBe('xyz');
return <div />;
}
});

ReactTestUtils.renderIntoDocument(
cloneWithProps(<Component />, {children: 'xyz'})
);
});

it('should shallow clone children', function() {
var Component = React.createClass({
render: function() {
expect(this.props.children).toBe('xyz');
return <div />;
}
});

ReactTestUtils.renderIntoDocument(
cloneWithProps(<Component>xyz</Component>, {})
);
});

it('should support keys and refs', function() {
var Component = React.createClass({
render: function() {
expect(this.props.key).toBe('xyz');
expect(this.props.ref).toBe('xyz');
return <div />;
}
});

var Parent = React.createClass({
render: function() {
var clone =
cloneWithProps(this.props.children, {key: 'xyz', ref: 'xyz'});
return <div>{clone}</div>;
}
});

var Grandparent = React.createClass({
render: function() {
return <Parent><Component key="abc" ref="abc" /></Parent>;
}
});

ReactTestUtils.renderIntoDocument(<Grandparent />);
});
});
29 changes: 27 additions & 2 deletions src/utils/cloneWithProps.js
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Expand Up @@ -21,6 +21,14 @@

var ReactPropTransferer = require('ReactPropTransferer');

var keyMirror = require('keyMirror');

var SpecialPropsToTransfer = keyMirror({
key: null,
children: null,
ref: null
});

/**
* Sometimes you want to change the props of a child passed to you. Usually
* this is to add a CSS class.
Expand All @@ -42,10 +50,27 @@ function cloneWithProps(child, props) {
}

var newProps = ReactPropTransferer.mergeProps(child.props, props);
// ReactPropTransferer does not transfer the `key` prop so do it manually.
if (props.key) {

// ReactPropTransferer does not transfer the `key` prop so do it manually. Do
// not transfer it from the original component.
if (props.hasOwnProperty(SpecialPropsToTransfer.key)) {
newProps.key = props.key;
}

// ReactPropTransferer does not transfer the `children` prop. Transfer it
// from `props` if it exists, otherwise use `child.props.children` if it is
// provided.
if (props.hasOwnProperty(SpecialPropsToTransfer.children)) {
newProps.children = props.children;
} else if (child.props.hasOwnProperty(SpecialPropsToTransfer.children)) {
newProps.children = child.props.children;
}

// ReactPropTransferer does not transfer `ref` so do it manually.
if (props.hasOwnProperty(SpecialPropsToTransfer.ref)) {
newProps.ref = props.ref;
}

return child.constructor.ConvenienceConstructor(newProps);
}

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