es5-sham.js
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/*!
* https://github.com/es-shims/es5-shim
* @license es5-shim Copyright 2009-2015 by contributors, MIT License
* see https://github.com/es-shims/es5-shim/blob/master/LICENSE
*/
// vim: ts=4 sts=4 sw=4 expandtab
// Add semicolon to prevent IIFE from being passed as argument to concatenated code.
;
// UMD (Universal Module Definition)
// see https://github.com/umdjs/umd/blob/master/templates/returnExports.js
(function (root, factory) {
'use strict';
/* global define, exports, module */
if (typeof define === 'function' && define.amd) {
// AMD. Register as an anonymous module.
define(factory);
} else if (typeof exports === 'object') {
// Node. Does not work with strict CommonJS, but
// only CommonJS-like enviroments that support module.exports,
// like Node.
module.exports = factory();
} else {
// Browser globals (root is window)
root.returnExports = factory();
}
}(this, function () {
var call = Function.call;
var prototypeOfObject = Object.prototype;
var owns = call.bind(prototypeOfObject.hasOwnProperty);
var isEnumerable = call.bind(prototypeOfObject.propertyIsEnumerable);
var toStr = call.bind(prototypeOfObject.toString);
// If JS engine supports accessors creating shortcuts.
var defineGetter;
var defineSetter;
var lookupGetter;
var lookupSetter;
var supportsAccessors = owns(prototypeOfObject, '__defineGetter__');
if (supportsAccessors) {
/* eslint-disable no-underscore-dangle */
defineGetter = call.bind(prototypeOfObject.__defineGetter__);
defineSetter = call.bind(prototypeOfObject.__defineSetter__);
lookupGetter = call.bind(prototypeOfObject.__lookupGetter__);
lookupSetter = call.bind(prototypeOfObject.__lookupSetter__);
/* eslint-enable no-underscore-dangle */
}
// ES5 15.2.3.2
// http://es5.github.com/#x15.2.3.2
if (!Object.getPrototypeOf) {
// https://github.com/es-shims/es5-shim/issues#issue/2
// http://ejohn.org/blog/objectgetprototypeof/
// recommended by fschaefer on github
//
// sure, and webreflection says ^_^
// ... this will nerever possibly return null
// ... Opera Mini breaks here with infinite loops
Object.getPrototypeOf = function getPrototypeOf(object) {
/* eslint-disable no-proto */
var proto = object.__proto__;
/* eslint-enable no-proto */
if (proto || proto === null) {
return proto;
} else if (toStr(object.constructor) === '[object Function]') {
return object.constructor.prototype;
} else if (object instanceof Object) {
return prototypeOfObject;
} else {
// Correctly return null for Objects created with `Object.create(null)`
// (shammed or native) or `{ __proto__: null}`. Also returns null for
// cross-realm objects on browsers that lack `__proto__` support (like
// IE <11), but that's the best we can do.
return null;
}
};
}
// ES5 15.2.3.3
// http://es5.github.com/#x15.2.3.3
var doesGetOwnPropertyDescriptorWork = function doesGetOwnPropertyDescriptorWork(object) {
try {
object.sentinel = 0;
return Object.getOwnPropertyDescriptor(object, 'sentinel').value === 0;
} catch (exception) {
return false;
}
};
// 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: ';
/* eslint-disable no-proto */
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
}
}
var descriptor;
// If object does not owns property return undefined immediately.
if (!owns(object, property)) {
return descriptor;
}
// If object has a property then it's for sure `configurable`, and
// probably `enumerable`. Detect enumerability though.
descriptor = {
enumerable: isEnumerable(object, property),
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__;
var notPrototypeOfObject = object !== prototypeOfObject;
// avoid recursion problem, breaking in Opera Mini when
// Object.getOwnPropertyDescriptor(Object.prototype, 'toString')
// or any other Object.prototype accessor
if (notPrototypeOfObject) {
object.__proto__ = prototypeOfObject;
}
var getter = lookupGetter(object, property);
var setter = lookupSetter(object, property);
if (notPrototypeOfObject) {
// 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;
};
/* eslint-enable no-proto */
}
// 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 = !({ __proto__: null } instanceof Object);
// the following produces false positives
// in Opera Mini => not a reliable check
// Object.prototype.__proto__ === null
// Check for document.domain and active x support
// No need to use active x approach when document.domain is not set
// see https://github.com/es-shims/es5-shim/issues/150
// variation of https://github.com/kitcambridge/es5-shim/commit/4f738ac066346
/* global ActiveXObject */
var shouldUseActiveX = function shouldUseActiveX() {
// return early if document.domain not set
if (!document.domain) {
return false;
}
try {
return !!new ActiveXObject('htmlfile');
} catch (exception) {
return false;
}
};
// This supports IE8 when document.domain is used
// see https://github.com/es-shims/es5-shim/issues/150
// variation of https://github.com/kitcambridge/es5-shim/commit/4f738ac066346
var getEmptyViaActiveX = function getEmptyViaActiveX() {
var empty;
var xDoc;
xDoc = new ActiveXObject('htmlfile');
var script = 'script';
xDoc.write('<' + script + '></' + script + '>');
xDoc.close();
empty = xDoc.parentWindow.Object.prototype;
xDoc = null;
return empty;
};
// The original implementation using an iframe
// before the activex approach was added
// see https://github.com/es-shims/es5-shim/issues/150
var getEmptyViaIFrame = function getEmptyViaIFrame() {
var iframe = document.createElement('iframe');
var parent = document.body || document.documentElement;
var empty;
iframe.style.display = 'none';
parent.appendChild(iframe);
/* eslint-disable no-script-url */
iframe.src = 'javascript:';
/* eslint-enable no-script-url */
empty = iframe.contentWindow.Object.prototype;
parent.removeChild(iframe);
iframe = null;
return empty;
};
/* global document */
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 () {
// Determine which approach to use
// see https://github.com/es-shims/es5-shim/issues/150
var empty = shouldUseActiveX() ? getEmptyViaActiveX() : getEmptyViaIFrame();
delete empty.constructor;
delete empty.hasOwnProperty;
delete empty.propertyIsEnumerable;
delete empty.isPrototypeOf;
delete empty.toLocaleString;
delete empty.toString;
delete empty.valueOf;
var Empty = 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;
var Type = 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`
/* eslint-disable no-proto */
object.__proto__ = prototype;
/* eslint-enable no-proto */
}
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/es-shims/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
var doesDefinePropertyWork = function doesDefinePropertyWork(object) {
try {
Object.defineProperty(object, 'sentinel', {});
return 'sentinel' in object;
} catch (exception) {
return false;
}
};
// 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 ('value' in descriptor) {
// 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
('writable' in descriptor && !descriptor.writable) ||
('enumerable' in descriptor && !descriptor.enumerable) ||
('configurable' in descriptor && !descriptor.configurable)
))
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.
/* eslint-disable no-proto */
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;
/* eslint-enable no-proto */
} else {
object[property] = descriptor.value;
}
} else {
if (!supportsAccessors && (('get' in descriptor) || ('set' in descriptor))) {
throw new TypeError(ERR_ACCESSORS_NOT_SUPPORTED);
}
// If we got that far then getters and setters can be defined !!
if ('get' in descriptor) {
defineGetter(object, property, descriptor.get);
}
if ('set' in descriptor) {
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
}
}
Object.keys(properties).forEach(function (property) {
if (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) {
if (Object(object) !== object) {
throw new TypeError('Object.seal can only be called on Objects.');
}
// 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) {
if (Object(object) !== object) {
throw new TypeError('Object.freeze can only be called on Objects.');
}
// 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 (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) {
if (Object(object) !== object) {
throw new TypeError('Object.preventExtensions can only be called on Objects.');
}
// 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) {
if (Object(object) !== object) {
throw new TypeError('Object.isSealed can only be called on Objects.');
}
return false;
};
}
// ES5 15.2.3.12
// http://es5.github.com/#x15.2.3.12
if (!Object.isFrozen) {
Object.isFrozen = function isFrozen(object) {
if (Object(object) !== object) {
throw new TypeError('Object.isFrozen can only be called on Objects.');
}
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('Object.isExtensible can only be called on Objects.');
}
// 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;
};
}
}));