| 'use strict'; | |
| 
 | |
| /** | |
|  * High performance assign before node6 | |
|  * @param {Object} target - target object | |
|  * @param {Object | Array} objects - object assign from | |
|  * @return {Object} - return target object | |
|  */ | |
| exports.assign = function(target, objects) { | |
|   if (!Array.isArray(objects)) { | |
|     objects = [ objects ]; | |
|   } | |
| 
 | |
|   for (var i = 0; i < objects.length; i++) { | |
|     var obj = objects[i]; | |
|     if (obj) { | |
|       var keys = Object.keys(obj); | |
|       for (var j = 0; j < keys.length; j++) { | |
|         var key = keys[j]; | |
|         target[key] = obj[key]; | |
|       } | |
|     } | |
|   } | |
|   return target; | |
| }; | |
| 
 | |
| exports.has = function has(obj, prop) { | |
|   return Object.prototype.hasOwnProperty.call(obj, prop); | |
| }; | |
| 
 | |
| /** | |
|  * Get all enumerable and ownership of property names | |
|  * @param {Object} obj - detect object | |
|  * @param {Boolean} [ignoreNull] - ignore null, undefined or NaN property | |
|  * @return {Array<String>} property names | |
|  */ | |
| exports.getOwnEnumerables = function getOwnEnumerables(obj, ignoreNull) { | |
|   if (!obj || typeof obj !== 'object' || Array.isArray(obj)) { | |
|     return []; | |
|   } | |
|   return Object.keys(obj).filter(function(key) { | |
|     if (ignoreNull) { | |
|       var value = obj[key]; | |
|       if (value === null || value === undefined || Number.isNaN(value)) { | |
|         return false; | |
|       } | |
|     } | |
|     return exports.has(obj, key); | |
|   }); | |
| }; | |
| 
 | |
| /** | |
|  * generate a real map object(clean object), no constructor, no __proto__ | |
|  * @param {Object} [obj] - init object, optional | |
|  * @return {Object} | |
|  */ | |
| exports.map = function map(obj) { | |
|   var map = new EmptyObject(); | |
|   if (!obj) { | |
|     return map; | |
|   } | |
| 
 | |
|   for (var key in obj) { | |
|     map[key] = obj[key]; | |
|   } | |
|   return map; | |
| }; | |
| 
 | |
| // faster way like `Object.create(null)` to get a 'clean' empty object | |
| // https://github.com/nodejs/node/blob/master/lib/events.js#L5 | |
| // https://cnodejs.org/topic/571e0c445a26c4a841ecbcf1 | |
| function EmptyObject() {} | |
| EmptyObject.prototype = Object.create(null);
 |