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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 () {
// ES5 15.2.3.2
if (!Object.getPrototypeOf) {
// recommended by fschaefer on github
Object.getPrototypeOf = function getPrototypeOf(object) {
return object.__proto__ || (
object.constructor
? object.constructor.prototype
: prototypeOfObject
);
};
}
// ES5 15.2.3.3
if (!Object.getOwnPropertyDescriptor) {
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);
}
// 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];
return descriptor;
};
}
// ES5 15.2.3.4
if (!Object.getOwnPropertyNames) {
Object.getOwnPropertyNames = function getOwnPropertyNames(object) {
return Object.keys(object);
};
}
// ES5 15.2.3.5
if (!Object.create) {
Object.create = function create(prototype, properties) {
var object;
if (prototype === null) {
object = { "__proto__": null };
} else {
if (typeof prototype != "object") {
throw new TypeError("typeof prototype["+(typeof prototype)+"] != 'object'");
}
var Type = function () {};
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
// Patch for WebKit and IE8 standard mode
// Designed by hax <hax.github.com>
// IE8 Reference:
// WebKit Bugs:
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;
}
}
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
if (!Object.defineProperties) {
Object.defineProperties = function defineProperties(object, properties) {
for (var property in properties) {
if (owns(properties, property) && property != "__proto__") {
Object.defineProperty(object, property, properties[property]);
}
}
return object;
};
}
// ES5 15.2.3.8
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
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
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
if (!Object.isSealed) {
Object.isSealed = function isSealed(object) {
return false;
};
}
// ES5 15.2.3.12
if (!Object.isFrozen) {
Object.isFrozen = function isFrozen(object) {
return false;
};
}
// ES5 15.2.3.13
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;
};
}
});