Remove `copyProperties`

Summary: remove `copyProperties` module, and replace the functionality with `Object.assign`

Reviewed By: javache

Differential Revision: D4745771

fbshipit-source-id: 2440620757e7539dbd7fd39f5920ac0b5b4183c5

Libraries/EventEmitter/EventValidator.js

@@ -11,8 +11,6 @@
  */
 'use strict';
 
-const copyProperties = require('copyProperties');
-
 /**
  * EventValidator is designed to validate event types to make it easier to catch
  * common mistakes. It accepts a map of all of the different types of events
@@ -37,7 +35,7 @@ const EventValidator = {
     const eventTypes = Object.keys(types);
     const emitterWithValidation = Object.create(emitter);
 
-    copyProperties(emitterWithValidation, {
+    Object.assign(emitterWithValidation, {
       emit: function emit(type, a, b, c, d, e, _) {
         assertAllowsEventType(type, eventTypes);
         return emitter.emit.call(this, type, a, b, c, d, e, _);

Libraries/EventEmitter/mixInEventEmitter.js

@@ -16,7 +16,6 @@ const EventEmitterWithHolding = require('EventEmitterWithHolding');
 const EventHolder = require('EventHolder');
 const EventValidator = require('EventValidator');
 
-const copyProperties = require('copyProperties');
 const invariant = require('fbjs/lib/invariant');
 const keyOf = require('fbjs/lib/keyOf');
 
@@ -63,13 +62,13 @@ function mixInEventEmitter(cls: Function | Object, types: Object) {
   // Keep track of the provided types, union the types if they already exist,
   // which allows for prototype subclasses to provide more types.
   if (target.hasOwnProperty(TYPES_KEY)) {
-    copyProperties(target.__types, types);
+    Object.assign(target.__types, types);
   } else if (target.__types) {
-    target.__types = copyProperties({}, target.__types, types);
+    target.__types = Object.assign({}, target.__types, types);
   } else {
     target.__types = types;
   }
-  copyProperties(target, EventEmitterMixin);
+  Object.assign(target, EventEmitterMixin);
 }
 
 const EventEmitterMixin = {

Libraries/vendor/core/copyProperties.js

@@ -1,48 +0,0 @@
-/**
- * Copyright (c) 2015-present, Facebook, Inc.
- * All rights reserved.
- *
- * This source code is licensed under the BSD-style license found in the
- * LICENSE file in the root directory of this source tree. An additional grant
- * of patent rights can be found in the PATENTS file in the same directory.
- *
- * @providesModule copyProperties
- */
-'use strict';
-
-/**
- * Copy properties from one or more objects (up to 5) into the first object.
- * This is a shallow copy. It mutates the first object and also returns it.
- *
- * NOTE: `arguments` has a very significant performance penalty, which is why
- * we don't support unlimited arguments.
- */
-function copyProperties(obj, a, b, c, d, e, f) {
-  obj = obj || {};
-
-  if (__DEV__) {
-    if (f) {
-      throw new Error('Too many arguments passed to copyProperties');
-    }
-  }
-
-  var args = [a, b, c, d, e];
-  var ii = 0, v;
-  while (args[ii]) {
-    v = args[ii++];
-    for (var k in v) {
-      obj[k] = v[k];
-    }
-
-    // IE ignores toString in object iteration.. See:
-    // webreflection.blogspot.com/2007/07/quick-fix-internet-explorer-and.html
-    if (v.hasOwnProperty && v.hasOwnProperty('toString') &&
-        (typeof v.toString !== 'undefined') && (obj.toString !== v.toString)) {
-      obj.toString = v.toString;
-    }
-  }
-
-  return obj;
-}
-
-module.exports = copyProperties;