/** | |
* lodash (Custom Build) <https://lodash.com/> | |
* Build: `lodash modularize exports="npm" -o ./` | |
* Copyright jQuery Foundation and other contributors <https://jquery.org/> | |
* Released under MIT license <https://lodash.com/license> | |
* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE> | |
* Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors | |
*/ | |
/** `Object#toString` result references. */ | |
var objectTag = '[object Object]'; | |
/** | |
* Checks if `value` is a host object in IE < 9. | |
* | |
* @private | |
* @param {*} value The value to check. | |
* @returns {boolean} Returns `true` if `value` is a host object, else `false`. | |
*/ | |
function isHostObject(value) { | |
// Many host objects are `Object` objects that can coerce to strings | |
// despite having improperly defined `toString` methods. | |
var result = false; | |
if (value != null && typeof value.toString != 'function') { | |
try { | |
result = !!(value + ''); | |
} catch (e) {} | |
} | |
return result; | |
} | |
/** | |
* Creates a unary function that invokes `func` with its argument transformed. | |
* | |
* @private | |
* @param {Function} func The function to wrap. | |
* @param {Function} transform The argument transform. | |
* @returns {Function} Returns the new function. | |
*/ | |
function overArg(func, transform) { | |
return function(arg) { | |
return func(transform(arg)); | |
}; | |
} | |
/** Used for built-in method references. */ | |
var funcProto = Function.prototype, | |
objectProto = Object.prototype; | |
/** Used to resolve the decompiled source of functions. */ | |
var funcToString = funcProto.toString; | |
/** Used to check objects for own properties. */ | |
var hasOwnProperty = objectProto.hasOwnProperty; | |
/** Used to infer the `Object` constructor. */ | |
var objectCtorString = funcToString.call(Object); | |
/** | |
* Used to resolve the | |
* [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring) | |
* of values. | |
*/ | |
var objectToString = objectProto.toString; | |
/** Built-in value references. */ | |
var getPrototype = overArg(Object.getPrototypeOf, Object); | |
/** | |
* Checks if `value` is object-like. A value is object-like if it's not `null` | |
* and has a `typeof` result of "object". | |
* | |
* @static | |
* @memberOf _ | |
* @since 4.0.0 | |
* @category Lang | |
* @param {*} value The value to check. | |
* @returns {boolean} Returns `true` if `value` is object-like, else `false`. | |
* @example | |
* | |
* _.isObjectLike({}); | |
* // => true | |
* | |
* _.isObjectLike([1, 2, 3]); | |
* // => true | |
* | |
* _.isObjectLike(_.noop); | |
* // => false | |
* | |
* _.isObjectLike(null); | |
* // => false | |
*/ | |
function isObjectLike(value) { | |
return !!value && typeof value == 'object'; | |
} | |
/** | |
* Checks if `value` is a plain object, that is, an object created by the | |
* `Object` constructor or one with a `[[Prototype]]` of `null`. | |
* | |
* @static | |
* @memberOf _ | |
* @since 0.8.0 | |
* @category Lang | |
* @param {*} value The value to check. | |
* @returns {boolean} Returns `true` if `value` is a plain object, else `false`. | |
* @example | |
* | |
* function Foo() { | |
* this.a = 1; | |
* } | |
* | |
* _.isPlainObject(new Foo); | |
* // => false | |
* | |
* _.isPlainObject([1, 2, 3]); | |
* // => false | |
* | |
* _.isPlainObject({ 'x': 0, 'y': 0 }); | |
* // => true | |
* | |
* _.isPlainObject(Object.create(null)); | |
* // => true | |
*/ | |
function isPlainObject(value) { | |
if (!isObjectLike(value) || | |
objectToString.call(value) != objectTag || isHostObject(value)) { | |
return false; | |
} | |
var proto = getPrototype(value); | |
if (proto === null) { | |
return true; | |
} | |
var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor; | |
return (typeof Ctor == 'function' && | |
Ctor instanceof Ctor && funcToString.call(Ctor) == objectCtorString); | |
} | |
module.exports = isPlainObject; | |