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// Copyright 2009-2012 by contributors, MIT License
// vim: ts=4 sts=4 sw=4 expandtab
// Module systems magic dance
(function (definition) { // RequireJS
if (typeof define == "function") { define(definition); // YUI3
} else if (typeof YUI == "function") { YUI.add("es5-sham", definition); // CommonJS and <script>
} else { definition(); } })(function () {
var call = Function.prototype.call; var prototypeOfObject = Object.prototype; var owns = call.bind(prototypeOfObject.hasOwnProperty);
// If JS engine supports accessors creating shortcuts.
var defineGetter; var defineSetter; var lookupGetter; var lookupSetter; var supportsAccessors; if ((supportsAccessors = owns(prototypeOfObject, "__defineGetter__"))) { defineGetter = call.bind(prototypeOfObject.__defineGetter__); defineSetter = call.bind(prototypeOfObject.__defineSetter__); lookupGetter = call.bind(prototypeOfObject.__lookupGetter__); lookupSetter = call.bind(prototypeOfObject.__lookupSetter__); }
// ES5 15.2.3.2
// http://es5.github.com/#x15.2.3.2
if (!Object.getPrototypeOf) { // https://github.com/kriskowal/es5-shim/issues#issue/2
// http://ejohn.org/blog/objectgetprototypeof/
// recommended by fschaefer on github
Object.getPrototypeOf = function getPrototypeOf(object) { return object.__proto__ || ( object.constructor ? object.constructor.prototype : prototypeOfObject ); }; }
//ES5 15.2.3.3
//http://es5.github.com/#x15.2.3.3
function doesGetOwnPropertyDescriptorWork(object) { try { object.sentinel = 0; return Object.getOwnPropertyDescriptor( object, "sentinel" ).value === 0; } catch (exception) { // returns falsy
} }
//check whether getOwnPropertyDescriptor works if it's given. Otherwise,
//shim partially.
if (Object.defineProperty) { var getOwnPropertyDescriptorWorksOnObject = doesGetOwnPropertyDescriptorWork({}); var getOwnPropertyDescriptorWorksOnDom = typeof document == "undefined" || doesGetOwnPropertyDescriptorWork(document.createElement("div")); if (!getOwnPropertyDescriptorWorksOnDom || !getOwnPropertyDescriptorWorksOnObject ) { var getOwnPropertyDescriptorFallback = Object.getOwnPropertyDescriptor; } }
if (!Object.getOwnPropertyDescriptor || getOwnPropertyDescriptorFallback) { var ERR_NON_OBJECT = "Object.getOwnPropertyDescriptor called on a non-object: ";
Object.getOwnPropertyDescriptor = function getOwnPropertyDescriptor(object, property) { if ((typeof object != "object" && typeof object != "function") || object === null) { throw new TypeError(ERR_NON_OBJECT + object); }
// make a valiant attempt to use the real getOwnPropertyDescriptor
// for I8's DOM elements.
if (getOwnPropertyDescriptorFallback) { try { return getOwnPropertyDescriptorFallback.call(Object, object, property); } catch (exception) { // try the shim if the real one doesn't work
} }
// If object does not owns property return undefined immediately.
if (!owns(object, property)) { return; }
// If object has a property then it's for sure both `enumerable` and
// `configurable`.
var descriptor = { enumerable: true, configurable: true };
// If JS engine supports accessor properties then property may be a
// getter or setter.
if (supportsAccessors) { // Unfortunately `__lookupGetter__` will return a getter even
// if object has own non getter property along with a same named
// inherited getter. To avoid misbehavior we temporary remove
// `__proto__` so that `__lookupGetter__` will return getter only
// if it's owned by an object.
var prototype = object.__proto__; object.__proto__ = prototypeOfObject;
var getter = lookupGetter(object, property); var setter = lookupSetter(object, property);
// Once we have getter and setter we can put values back.
object.__proto__ = prototype;
if (getter || setter) { if (getter) { descriptor.get = getter; } if (setter) { descriptor.set = setter; } // If it was accessor property we're done and return here
// in order to avoid adding `value` to the descriptor.
return descriptor; } }
// If we got this far we know that object has an own property that is
// not an accessor so we set it as a value and return descriptor.
descriptor.value = object[property]; descriptor.writable = true; return descriptor; }; }
// ES5 15.2.3.4
// http://es5.github.com/#x15.2.3.4
if (!Object.getOwnPropertyNames) { Object.getOwnPropertyNames = function getOwnPropertyNames(object) { return Object.keys(object); }; }
// ES5 15.2.3.5
// http://es5.github.com/#x15.2.3.5
if (!Object.create) {
// Contributed by Brandon Benvie, October, 2012
var createEmpty; var supportsProto = Object.prototype.__proto__ === null; if (supportsProto || typeof document == 'undefined') { createEmpty = function () { return { "__proto__": null }; }; } else { // In old IE __proto__ can't be used to manually set `null`, nor does
// any other method exist to make an object that inherits from nothing,
// aside from Object.prototype itself. Instead, create a new global
// object and *steal* its Object.prototype and strip it bare. This is
// used as the prototype to create nullary objects.
createEmpty = function () { var iframe = document.createElement('iframe'); var parent = document.body || document.documentElement; iframe.style.display = 'none'; parent.appendChild(iframe); iframe.src = 'javascript:'; var empty = iframe.contentWindow.Object.prototype; parent.removeChild(iframe); iframe = null; delete empty.constructor; delete empty.hasOwnProperty; delete empty.propertyIsEnumerable; delete empty.isPrototypeOf; delete empty.toLocaleString; delete empty.toString; delete empty.valueOf; empty.__proto__ = null;
function Empty() {} Empty.prototype = empty; // short-circuit future calls
createEmpty = function () { return new Empty(); }; return new Empty(); }; }
Object.create = function create(prototype, properties) {
var object; function Type() {} // An empty constructor.
if (prototype === null) { object = createEmpty(); } else { if (typeof prototype !== "object" && typeof prototype !== "function") { // In the native implementation `parent` can be `null`
// OR *any* `instanceof Object` (Object|Function|Array|RegExp|etc)
// Use `typeof` tho, b/c in old IE, DOM elements are not `instanceof Object`
// like they are in modern browsers. Using `Object.create` on DOM elements
// is...err...probably inappropriate, but the native version allows for it.
throw new TypeError("Object prototype may only be an Object or null"); // same msg as Chrome
} Type.prototype = prototype; object = new Type(); // IE has no built-in implementation of `Object.getPrototypeOf`
// neither `__proto__`, but this manually setting `__proto__` will
// guarantee that `Object.getPrototypeOf` will work as expected with
// objects created using `Object.create`
object.__proto__ = prototype; }
if (properties !== void 0) { Object.defineProperties(object, properties); }
return object; }; }
// ES5 15.2.3.6
// http://es5.github.com/#x15.2.3.6
// Patch for WebKit and IE8 standard mode
// Designed by hax <hax.github.com>
// related issue: https://github.com/kriskowal/es5-shim/issues#issue/5
// IE8 Reference:
// http://msdn.microsoft.com/en-us/library/dd282900.aspx
// http://msdn.microsoft.com/en-us/library/dd229916.aspx
// WebKit Bugs:
// https://bugs.webkit.org/show_bug.cgi?id=36423
function doesDefinePropertyWork(object) { try { Object.defineProperty(object, "sentinel", {}); return "sentinel" in object; } catch (exception) { // returns falsy
} }
// check whether defineProperty works if it's given. Otherwise,
// shim partially.
if (Object.defineProperty) { var definePropertyWorksOnObject = doesDefinePropertyWork({}); var definePropertyWorksOnDom = typeof document == "undefined" || doesDefinePropertyWork(document.createElement("div")); if (!definePropertyWorksOnObject || !definePropertyWorksOnDom) { var definePropertyFallback = Object.defineProperty, definePropertiesFallback = Object.defineProperties; } }
if (!Object.defineProperty || definePropertyFallback) { var ERR_NON_OBJECT_DESCRIPTOR = "Property description must be an object: "; var ERR_NON_OBJECT_TARGET = "Object.defineProperty called on non-object: " var ERR_ACCESSORS_NOT_SUPPORTED = "getters & setters can not be defined " + "on this javascript engine";
Object.defineProperty = function defineProperty(object, property, descriptor) { if ((typeof object != "object" && typeof object != "function") || object === null) { throw new TypeError(ERR_NON_OBJECT_TARGET + object); } if ((typeof descriptor != "object" && typeof descriptor != "function") || descriptor === null) { throw new TypeError(ERR_NON_OBJECT_DESCRIPTOR + descriptor); } // make a valiant attempt to use the real defineProperty
// for I8's DOM elements.
if (definePropertyFallback) { try { return definePropertyFallback.call(Object, object, property, descriptor); } catch (exception) { // try the shim if the real one doesn't work
} }
// If it's a data property.
if (owns(descriptor, "value")) { // fail silently if "writable", "enumerable", or "configurable"
// are requested but not supported
/* // alternate approach:
if ( // can't implement these features; allow false but not true
!(owns(descriptor, "writable") ? descriptor.writable : true) || !(owns(descriptor, "enumerable") ? descriptor.enumerable : true) || !(owns(descriptor, "configurable") ? descriptor.configurable : true) ) throw new RangeError( "This implementation of Object.defineProperty does not " + "support configurable, enumerable, or writable." ); */
if (supportsAccessors && (lookupGetter(object, property) || lookupSetter(object, property))) { // As accessors are supported only on engines implementing
// `__proto__` we can safely override `__proto__` while defining
// a property to make sure that we don't hit an inherited
// accessor.
var prototype = object.__proto__; object.__proto__ = prototypeOfObject; // Deleting a property anyway since getter / setter may be
// defined on object itself.
delete object[property]; object[property] = descriptor.value; // Setting original `__proto__` back now.
object.__proto__ = prototype; } else { object[property] = descriptor.value; } } else { if (!supportsAccessors) { throw new TypeError(ERR_ACCESSORS_NOT_SUPPORTED); } // If we got that far then getters and setters can be defined !!
if (owns(descriptor, "get")) { defineGetter(object, property, descriptor.get); } if (owns(descriptor, "set")) { defineSetter(object, property, descriptor.set); } } return object; }; }
// ES5 15.2.3.7
// http://es5.github.com/#x15.2.3.7
if (!Object.defineProperties || definePropertiesFallback) { Object.defineProperties = function defineProperties(object, properties) { // make a valiant attempt to use the real defineProperties
if (definePropertiesFallback) { try { return definePropertiesFallback.call(Object, object, properties); } catch (exception) { // try the shim if the real one doesn't work
} }
for (var property in properties) { if (owns(properties, property) && property != "__proto__") { Object.defineProperty(object, property, properties[property]); } } return object; }; }
// ES5 15.2.3.8
// http://es5.github.com/#x15.2.3.8
if (!Object.seal) { Object.seal = function seal(object) { // this is misleading and breaks feature-detection, but
// allows "securable" code to "gracefully" degrade to working
// but insecure code.
return object; }; }
// ES5 15.2.3.9
// http://es5.github.com/#x15.2.3.9
if (!Object.freeze) { Object.freeze = function freeze(object) { // this is misleading and breaks feature-detection, but
// allows "securable" code to "gracefully" degrade to working
// but insecure code.
return object; }; }
// detect a Rhino bug and patch it
try { Object.freeze(function () {}); } catch (exception) { Object.freeze = (function freeze(freezeObject) { return function freeze(object) { if (typeof object == "function") { return object; } else { return freezeObject(object); } }; })(Object.freeze); }
// ES5 15.2.3.10
// http://es5.github.com/#x15.2.3.10
if (!Object.preventExtensions) { Object.preventExtensions = function preventExtensions(object) { // this is misleading and breaks feature-detection, but
// allows "securable" code to "gracefully" degrade to working
// but insecure code.
return object; }; }
// ES5 15.2.3.11
// http://es5.github.com/#x15.2.3.11
if (!Object.isSealed) { Object.isSealed = function isSealed(object) { return false; }; }
// ES5 15.2.3.12
// http://es5.github.com/#x15.2.3.12
if (!Object.isFrozen) { Object.isFrozen = function isFrozen(object) { return false; }; }
// ES5 15.2.3.13
// http://es5.github.com/#x15.2.3.13
if (!Object.isExtensible) { Object.isExtensible = function isExtensible(object) { // 1. If Type(O) is not Object throw a TypeError exception.
if (Object(object) !== object) { throw new TypeError(); // TODO message
} // 2. Return the Boolean value of the [[Extensible]] internal property of O.
var name = ''; while (owns(object, name)) { name += '?'; } object[name] = true; var returnValue = owns(object, name); delete object[name]; return returnValue; }; }
});
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