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Object.defineProperty polyfill
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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, no-restricted-properties */ | |
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, no-restricted-properties */ | |
} | |
var isPrimitive = function isPrimitive(o) { | |
return o == null || (typeof o !== 'object' && typeof o !== 'function'); | |
}; | |
// 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-next-line no-proto | |
var proto = object.__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 (isPrimitive(object)) { | |
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-next-line no-script-url | |
iframe.src = 'javascript:'; | |
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 (prototype !== null && isPrimitive(prototype)) { | |
// 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-next-line no-proto | |
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/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 (isPrimitive(object)) { | |
throw new TypeError(ERR_NON_OBJECT_TARGET + object); | |
} | |
if (isPrimitive(descriptor)) { | |
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 { | |
var hasGetter = 'get' in descriptor; | |
var hasSetter = 'set' in descriptor; | |
if (!supportsAccessors && (hasGetter || hasSetter)) { | |
throw new TypeError(ERR_ACCESSORS_NOT_SUPPORTED); | |
} | |
// If we got that far then getters and setters can be defined !! | |
if (hasGetter) { | |
defineGetter(object, property, descriptor.get); | |
} | |
if (hasSetter) { | |
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; | |
}; | |
} | |
})); |
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Will it run in all Device?