var getTag = require('./_getTag'), isArguments = require('./isArguments'), isArray = require('./isArray'), isArrayLike = require('./isArrayLike'), isBuffer = require('./isBuffer'), isPrototype = require('./_isPrototype'), nativeKeys = require('./_nativeKeys'); /** `Object#toString` result references. */ var mapTag = '[object Map]', setTag = '[object Set]'; /** Used for built-in method references. */ var objectProto = Object.prototype; /** Used to check objects for own properties. */ var hasOwnProperty = objectProto.hasOwnProperty; /** Built-in value references. */ var propertyIsEnumerable = objectProto.propertyIsEnumerable; /** Detect if properties shadowing those on `Object.prototype` are non-enumerable. */ var nonEnumShadows = !propertyIsEnumerable.call({ 'valueOf': 1 }, 'valueOf'); /** * Checks if `value` is an empty object, collection, map, or set. * * Objects are considered empty if they have no own enumerable string keyed * properties. * * Array-like values such as `arguments` objects, arrays, buffers, strings, or * jQuery-like collections are considered empty if they have a `length` of `0`. * Similarly, maps and sets are considered empty if they have a `size` of `0`. * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is empty, else `false`. * @example * * _.isEmpty(null); * // => true * * _.isEmpty(true); * // => true * * _.isEmpty(1); * // => true * * _.isEmpty([1, 2, 3]); * // => false * * _.isEmpty({ 'a': 1 }); * // => false */ function isEmpty(value) { if (isArrayLike(value) && (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' || isBuffer(value) || isArguments(value))) { return !value.length; } var tag = getTag(value); if (tag == mapTag || tag == setTag) { return !value.size; } if (nonEnumShadows || isPrototype(value)) { return !nativeKeys(value).length; } for (var key in value) { if (hasOwnProperty.call(value, key)) { return false; } } return true; } module.exports = isEmpty;