From b4df18c1758160586dde20f4cfd072379edc339d Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinklemail@gmail.com>
Date: Mon, 28 Jul 2014 20:17:21 +0100
Subject: [PATCH] es5-shim: Add polyfill for Object.create

Follows-up fff9a814f2327eb. Per the OOjs readme, it requires:

> (..) parser compatibility with ES3 engines.
> To support ES3 engines, ensure an appropriate polyfill is
> loaded for these methods:
> * Array.isArray
> * Object.create (basic use only)
> * Object.keys
> * JSON.stringify

The es5-shim and oojs modules already provide JSON, and most
Array and Object methods. Except for Object.create because there
are a few features in it that can't be emulated, and hence
es5-shim refuses to ship the polyfill for it.

Bug: 67590
Change-Id: I4838d78f77a3a71f80e6750adb914213b5ca4df5
---
 resources/Resources.php                 |  1 +
 resources/src/polyfill-object-create.js | 62 +++++++++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 resources/src/polyfill-object-create.js

diff --git a/resources/Resources.php b/resources/Resources.php
index 99e1e4fd39..29c74ee015 100644
--- a/resources/Resources.php
+++ b/resources/Resources.php
@@ -1500,6 +1500,7 @@ return array(
 	'es5-shim' => array(
 		'scripts' => array(
 			'resources/lib/es5-shim/es5-shim.js',
+			'resources/src/polyfill-object-create.js',
 		),
 		'targets' => array( 'desktop', 'mobile' ),
 		'skipFunction' => 'resources/src/es5-skip.js',
diff --git a/resources/src/polyfill-object-create.js b/resources/src/polyfill-object-create.js
new file mode 100644
index 0000000000..607faf649f
--- /dev/null
+++ b/resources/src/polyfill-object-create.js
@@ -0,0 +1,62 @@
+/**
+ * Simplified version of es5-sham#Object-create that also works around a bug
+ * in the actual es5-sham: https://github.com/es-shims/es5-shim/issues/252
+ *
+ * Does not:
+ * - Support empty inheritance via `Object.create(null)`.
+ * - Support getter and setter accessors via `Object.create( .., properties )`.
+ * - Support custom property descriptor (e.g. writable, configurtable, enumerable).
+ * - Leave behind an enumerable "__proto__" all over the place.
+ *
+ * @author Timo Tijhof, 2014
+ */
+
+// ES5 15.2.3.5
+// http://es5.github.com/#x15.2.3.5
+if ( !Object.create ) {
+	( function () {
+		var hasOwn = Object.hasOwnProperty,
+			// https://developer.mozilla.org/en-US/docs/ECMAScript_DontEnum_attribute#JScript_DontEnum_Bug
+			// http://whattheheadsaid.com/2010/10/a-safer-object-keys-compatibility-implementation
+			isEnumBug = !{ valueOf: 0 }.propertyIsEnumerable( 'valueOf' );
+
+		// Reusable constructor function for Object.create
+		function Empty() {}
+
+		function defineProperty( object, key, property ) {
+			if ( hasOwn.call( property, 'value' ) ) {
+				object[ key ] = property.value;
+			} else {
+				object[ key ] = property;
+			}
+		}
+
+		Object.create = function create( prototype, properties ) {
+			var object, key;
+
+			if ( prototype !== Object( prototype ) ) {
+				throw new TypeError( 'Called on non-object' );
+			}
+
+			Empty.prototype = prototype;
+			object = new Empty();
+
+			if ( properties !== undefined ) {
+				if ( !isEnumBug ) {
+					for ( key in properties ) {
+						if ( hasOwn.call( properties, key ) ) {
+							defineProperty( object, key, properties[ key ] );
+						}
+					}
+				} else {
+					Object.keys( properties ).forEach( function ( key ) {
+						defineProperty( object, key, properties[ key ] );
+					} );
+				}
+			}
+
+			return object;
+		};
+
+	}() );
+}
-- 
2.20.1