var baseForIn = require('./baseForIn'), isObjectLike = require('./isObjectLike'); /** `Object#toString` result references. */ var objectTag = '[object Object]'; /** Used for native method references. */ var objectProto = Object.prototype; /** Used to check objects for own properties. */ var hasOwnProperty = objectProto.hasOwnProperty; /** * Used to resolve the [`toStringTag`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring) * of values. */ var objToString = objectProto.toString; /** * A fallback implementation of `_.isPlainObject` which checks if `value` * is an object created by the `Object` constructor or has a `[[Prototype]]` * of `null`. * * @private * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a plain object, else `false`. */ function shimIsPlainObject(value) { var Ctor; // Exit early for non `Object` objects. if (!(isObjectLike(value) && objToString.call(value) == objectTag) || (!hasOwnProperty.call(value, 'constructor') && (Ctor = value.constructor, typeof Ctor == 'function' && !(Ctor instanceof Ctor)))) { return false; } // IE < 9 iterates inherited properties before own properties. If the first // iterated property is an object's own property then there are no inherited // enumerable properties. var result; // In most environments an object's own properties are iterated before // its inherited properties. If the last iterated property is an object's // own property then there are no inherited enumerable properties. baseForIn(value, function(subValue, key) { result = key; }); return result === undefined || hasOwnProperty.call(value, result); } module.exports = shimIsPlainObject;