Hide Object.assign polyfill behind a module

Because the JS community's polyfilling infrastructure sucks and we'll
have to fix it for them before we require this.

JSX spread uses React.__spread
(which might get special behavior for key/ref, not sure yet)

This never uses the native implementation and throws for prototype chains.
Once the native implementations are faster, we'll start using them.

jest/environment.js

@@ -1,3 +1 @@
 __DEV__ = true;
-
-require.requireActual('../src/vendor/polyfill/Object.es6.js');

src/addons/transitions/ReactCSSTransitionGroup.js

@@ -14,6 +14,8 @@
 
 var React = require('React');
 
+var assign = require('Object.assign');
+
 var ReactTransitionGroup = React.createFactory(
   require('ReactTransitionGroup')
 );
@@ -54,7 +56,7 @@ var ReactCSSTransitionGroup = React.createClass({
   render: function() {
     return (
       ReactTransitionGroup(
-        Object.assign({}, this.props, {childFactory: this._wrapChild})
+        assign({}, this.props, {childFactory: this._wrapChild})
       )
     );
   }

src/addons/transitions/ReactTransitionGroup.js

@@ -14,6 +14,7 @@
 var React = require('React');
 var ReactTransitionChildMapping = require('ReactTransitionChildMapping');
 
+var assign = require('Object.assign');
 var cloneWithProps = require('cloneWithProps');
 var emptyFunction = require('emptyFunction');
 
@@ -151,7 +152,7 @@ var ReactTransitionGroup = React.createClass({
       // This entered again before it fully left. Add it again.
       this.performEnter(key);
     } else {
-      var newChildren = Object.assign({}, this.state.children);
+      var newChildren = assign({}, this.state.children);
       delete newChildren[key];
       this.setState({children: newChildren});
     }

src/addons/update.js

@@ -11,14 +11,15 @@
 
 "use strict";
 
+var assign = require('Object.assign');
 var keyOf = require('keyOf');
 var invariant = require('invariant');
 
 function shallowCopy(x) {
   if (Array.isArray(x)) {
     return x.concat();
   } else if (x && typeof x === 'object') {
-    return Object.assign(new x.constructor(), x);
+    return assign(new x.constructor(), x);
   } else {
     return x;
   }
@@ -98,7 +99,7 @@ function update(value, spec) {
       COMMAND_MERGE,
       nextValue
     );
-    Object.assign(nextValue, spec[COMMAND_MERGE]);
+    assign(nextValue, spec[COMMAND_MERGE]);
   }
 
   if (spec.hasOwnProperty(COMMAND_PUSH)) {

src/browser/ReactBrowserEventEmitter.js

@@ -18,6 +18,7 @@ var EventPluginRegistry = require('EventPluginRegistry');
 var ReactEventEmitterMixin = require('ReactEventEmitterMixin');
 var ViewportMetrics = require('ViewportMetrics');
 
+var assign = require('Object.assign');
 var isEventSupported = require('isEventSupported');
 
 /**
@@ -147,7 +148,7 @@ function getListeningForDocument(mountAt) {
  *
  * @internal
  */
-var ReactBrowserEventEmitter = Object.assign({}, ReactEventEmitterMixin, {
+var ReactBrowserEventEmitter = assign({}, ReactEventEmitterMixin, {
 
   /**
    * Injectable event backend

src/browser/ReactPutListenerQueue.js

@@ -14,11 +14,13 @@
 var PooledClass = require('PooledClass');
 var ReactBrowserEventEmitter = require('ReactBrowserEventEmitter');
 
+var assign = require('Object.assign');
+
 function ReactPutListenerQueue() {
   this.listenersToPut = [];
 }
 
-Object.assign(ReactPutListenerQueue.prototype, {
+assign(ReactPutListenerQueue.prototype, {
   enqueuePutListener: function(rootNodeID, propKey, propValue) {
     this.listenersToPut.push({
       rootNodeID: rootNodeID,

src/browser/ReactReconcileTransaction.js

@@ -19,6 +19,8 @@ var ReactInputSelection = require('ReactInputSelection');
 var ReactPutListenerQueue = require('ReactPutListenerQueue');
 var Transaction = require('Transaction');
 
+var assign = require('Object.assign');
+
 /**
  * Ensures that, when possible, the selection range (currently selected text
  * input) is not disturbed by performing the transaction.
@@ -165,7 +167,7 @@ var Mixin = {
 };
 
 
-Object.assign(ReactReconcileTransaction.prototype, Transaction.Mixin, Mixin);
+assign(ReactReconcileTransaction.prototype, Transaction.Mixin, Mixin);
 
 PooledClass.addPoolingTo(ReactReconcileTransaction);
 

src/browser/ReactTextComponent.js

@@ -16,6 +16,7 @@ var DOMPropertyOperations = require('DOMPropertyOperations');
 var ReactComponent = require('ReactComponent');
 var ReactElement = require('ReactElement');
 
+var assign = require('Object.assign');
 var escapeTextForBrowser = require('escapeTextForBrowser');
 
 /**
@@ -37,7 +38,7 @@ var ReactTextComponent = function(props) {
   // This constructor and it's argument is currently used by mocks.
 };
 
-Object.assign(ReactTextComponent.prototype, ReactComponent.Mixin, {
+assign(ReactTextComponent.prototype, ReactComponent.Mixin, {
 
   /**
    * Creates the markup for this text node. This node is not intended to have

src/browser/server/ReactServerRenderingTransaction.js

@@ -17,6 +17,7 @@ var CallbackQueue = require('CallbackQueue');
 var ReactPutListenerQueue = require('ReactPutListenerQueue');
 var Transaction = require('Transaction');
 
+var assign = require('Object.assign');
 var emptyFunction = require('emptyFunction');
 
 /**
@@ -99,7 +100,7 @@ var Mixin = {
 };
 
 
-Object.assign(
+assign(
   ReactServerRenderingTransaction.prototype,
   Transaction.Mixin,
   Mixin

src/browser/syntheticEvents/SyntheticEvent.js

@@ -14,6 +14,7 @@
 
 var PooledClass = require('PooledClass');
 
+var assign = require('Object.assign');
 var emptyFunction = require('emptyFunction');
 var getEventTarget = require('getEventTarget');
 
@@ -82,7 +83,7 @@ function SyntheticEvent(dispatchConfig, dispatchMarker, nativeEvent) {
   this.isPropagationStopped = emptyFunction.thatReturnsFalse;
 }
 
-Object.assign(SyntheticEvent.prototype, {
+assign(SyntheticEvent.prototype, {
 
   preventDefault: function() {
     this.defaultPrevented = true;
@@ -140,11 +141,11 @@ SyntheticEvent.augmentClass = function(Class, Interface) {
   var Super = this;
 
   var prototype = Object.create(Super.prototype);
-  Object.assign(prototype, Class.prototype);
+  assign(prototype, Class.prototype);
   Class.prototype = prototype;
   Class.prototype.constructor = Class;
 
-  Class.Interface = Object.assign({}, Super.Interface, Interface);
+  Class.Interface = assign({}, Super.Interface, Interface);
   Class.augmentClass = Super.augmentClass;
 
   PooledClass.addPoolingTo(Class, PooledClass.threeArgumentPooler);

src/browser/ui/React.js

@@ -11,10 +11,6 @@
 
 "use strict";
 
-// TODO: Move this elsewhere - it only exists in open source until a better
-// solution is found.
-require('Object.es6');
-
 var DOMPropertyOperations = require('DOMPropertyOperations');
 var EventPluginUtils = require('EventPluginUtils');
 var ReactChildren = require('ReactChildren');
@@ -36,6 +32,7 @@ var ReactPropTypes = require('ReactPropTypes');
 var ReactServerRendering = require('ReactServerRendering');
 var ReactTextComponent = require('ReactTextComponent');
 
+var assign = require('Object.assign');
 var deprecated = require('deprecated');
 var onlyChild = require('onlyChild');
 
@@ -84,6 +81,9 @@ var React = {
   isValidElement: ReactElement.isValidElement,
   withContext: ReactContext.withContext,
 
+  // Hook for JSX spread, don't use this for anything else.
+  __spread: assign,
+
   // Deprecations (remove for 0.13)
   renderComponent: deprecated(
     'React',

src/browser/ui/ReactDOMComponent.js

@@ -22,6 +22,7 @@ var ReactMount = require('ReactMount');
 var ReactMultiChild = require('ReactMultiChild');
 var ReactPerf = require('ReactPerf');
 
+var assign = require('Object.assign');
 var escapeTextForBrowser = require('escapeTextForBrowser');
 var invariant = require('invariant');
 var isEventSupported = require('isEventSupported');
@@ -213,7 +214,7 @@ ReactDOMComponent.Mixin = {
       } else {
         if (propKey === STYLE) {
           if (propValue) {
-            propValue = props.style = Object.assign({}, props.style);
+            propValue = props.style = assign({}, props.style);
           }
           propValue = CSSPropertyOperations.createMarkupForStyles(propValue);
         }
@@ -362,7 +363,7 @@ ReactDOMComponent.Mixin = {
       }
       if (propKey === STYLE) {
         if (nextProp) {
-          nextProp = nextProps.style = Object.assign({}, nextProp);
+          nextProp = nextProps.style = assign({}, nextProp);
         }
         if (lastProp) {
           // Unset styles on `lastProp` but not on `nextProp`.
@@ -471,7 +472,7 @@ ReactDOMComponent.Mixin = {
 
 };
 
-Object.assign(
+assign(
   ReactDOMComponent.prototype,
   ReactComponent.Mixin,
   ReactDOMComponent.Mixin,

src/browser/ui/ReactEventListener.js

@@ -19,6 +19,7 @@ var ReactInstanceHandles = require('ReactInstanceHandles');
 var ReactMount = require('ReactMount');
 var ReactUpdates = require('ReactUpdates');
 
+var assign = require('Object.assign');
 var getEventTarget = require('getEventTarget');
 var getUnboundedScrollPosition = require('getUnboundedScrollPosition');
 
@@ -46,7 +47,7 @@ function TopLevelCallbackBookKeeping(topLevelType, nativeEvent) {
   this.nativeEvent = nativeEvent;
   this.ancestors = [];
 }
-Object.assign(TopLevelCallbackBookKeeping.prototype, {
+assign(TopLevelCallbackBookKeeping.prototype, {
   destructor: function() {
     this.topLevelType = null;
     this.nativeEvent = null;

src/browser/ui/__tests__/ReactDOMComponent-test.js

@@ -13,6 +13,7 @@
 
 "use strict";
 
+var assign = require('Object.assign');
 var mocks = require('mocks');
 
 describe('ReactDOMComponent', function() {
@@ -223,7 +224,7 @@ describe('ReactDOMComponent', function() {
         this.props = initialProps || {};
         this._rootNodeID = 'test';
       };
-      Object.assign(NodeStub.prototype, ReactDOMComponent.Mixin);
+      assign(NodeStub.prototype, ReactDOMComponent.Mixin);
 
       genMarkup = function(props) {
         var transaction = new ReactReconcileTransaction();
@@ -273,7 +274,7 @@ describe('ReactDOMComponent', function() {
         this.props = initialProps || {};
         this._rootNodeID = 'test';
       };
-      Object.assign(NodeStub.prototype, ReactDOMComponent.Mixin);
+      assign(NodeStub.prototype, ReactDOMComponent.Mixin);
 
       genMarkup = function(props) {
         var transaction = new ReactReconcileTransaction();
@@ -310,9 +311,9 @@ describe('ReactDOMComponent', function() {
       var StubNativeComponent = function(element) {
         ReactComponent.Mixin.construct.call(this, element);
       };
-      Object.assign(StubNativeComponent.prototype, ReactComponent.Mixin);
-      Object.assign(StubNativeComponent.prototype, ReactDOMComponent.Mixin);
-      Object.assign(StubNativeComponent.prototype, ReactMultiChild.Mixin);
+      assign(StubNativeComponent.prototype, ReactComponent.Mixin);
+      assign(StubNativeComponent.prototype, ReactDOMComponent.Mixin);
+      assign(StubNativeComponent.prototype, ReactMultiChild.Mixin);
 
       mountComponent = function(props) {
         var transaction = new ReactReconcileTransaction();

src/browser/ui/dom/components/ReactDOMInput.js

@@ -21,6 +21,7 @@ var ReactDOM = require('ReactDOM');
 var ReactMount = require('ReactMount');
 var ReactUpdates = require('ReactUpdates');
 
+var assign = require('Object.assign');
 var invariant = require('invariant');
 
 // Store a reference to the <input> `ReactDOMComponent`. TODO: use string
@@ -66,7 +67,7 @@ var ReactDOMInput = ReactCompositeComponent.createClass({
 
   render: function() {
     // Clone `this.props` so we don't mutate the input.
-    var props = Object.assign({}, this.props);
+    var props = assign({}, this.props);
 
     props.defaultChecked = null;
     props.defaultValue = null;

src/browser/ui/dom/components/ReactDOMSelect.js

@@ -19,6 +19,8 @@ var ReactElement = require('ReactElement');
 var ReactDOM = require('ReactDOM');
 var ReactUpdates = require('ReactUpdates');
 
+var assign = require('Object.assign');
+
 // Store a reference to the <select> `ReactDOMComponent`. TODO: use string
 var select = ReactElement.createFactory(ReactDOM.select.type);
 
@@ -129,7 +131,7 @@ var ReactDOMSelect = ReactCompositeComponent.createClass({
 
   render: function() {
     // Clone `this.props` so we don't mutate the input.
-    var props = Object.assign({}, this.props);
+    var props = assign({}, this.props);
 
     props.onChange = this._handleChange;
     props.value = null;

src/browser/ui/dom/components/ReactDOMTextarea.js

@@ -20,6 +20,7 @@ var ReactElement = require('ReactElement');
 var ReactDOM = require('ReactDOM');
 var ReactUpdates = require('ReactUpdates');
 
+var assign = require('Object.assign');
 var invariant = require('invariant');
 
 var warning = require('warning');
@@ -95,7 +96,7 @@ var ReactDOMTextarea = ReactCompositeComponent.createClass({
 
   render: function() {
     // Clone `this.props` so we don't mutate the input.
-    var props = Object.assign({}, this.props);
+    var props = assign({}, this.props);
 
     invariant(
       props.dangerouslySetInnerHTML == null,

src/core/ReactComponent.js

@@ -15,6 +15,7 @@ var ReactElement = require('ReactElement');
 var ReactOwner = require('ReactOwner');
 var ReactUpdates = require('ReactUpdates');
 
+var assign = require('Object.assign');
 var invariant = require('invariant');
 var keyMirror = require('keyMirror');
 
@@ -143,7 +144,7 @@ var ReactComponent = {
       // element props.
       var element = this._pendingElement || this._currentElement;
       this.replaceProps(
-        Object.assign({}, element.props, partialProps),
+        assign({}, element.props, partialProps),
         callback
       );
     },
@@ -192,7 +193,7 @@ var ReactComponent = {
       var element = this._pendingElement || this._currentElement;
       this._pendingElement = ReactElement.cloneAndReplaceProps(
         element,
-        Object.assign({}, element.props, partialProps)
+        assign({}, element.props, partialProps)
       );
       ReactUpdates.enqueueUpdate(this, callback);
     },