| /*! | |
|  * merge-descriptors | |
|  * Copyright(c) 2014 Jonathan Ong | |
|  * Copyright(c) 2015 Douglas Christopher Wilson | |
|  * MIT Licensed | |
|  */ | |
| 
 | |
| 'use strict' | |
| 
 | |
| /** | |
|  * Module exports. | |
|  * @public | |
|  */ | |
| 
 | |
| module.exports = merge | |
| 
 | |
| /** | |
|  * Module variables. | |
|  * @private | |
|  */ | |
| 
 | |
| var hasOwnProperty = Object.prototype.hasOwnProperty | |
| 
 | |
| /** | |
|  * Merge the property descriptors of `src` into `dest` | |
|  * | |
|  * @param {object} dest Object to add descriptors to | |
|  * @param {object} src Object to clone descriptors from | |
|  * @param {boolean} [redefine=true] Redefine `dest` properties with `src` properties | |
|  * @returns {object} Reference to dest | |
|  * @public | |
|  */ | |
| 
 | |
| function merge (dest, src, redefine) { | |
|   if (!dest) { | |
|     throw new TypeError('argument dest is required') | |
|   } | |
| 
 | |
|   if (!src) { | |
|     throw new TypeError('argument src is required') | |
|   } | |
| 
 | |
|   if (redefine === undefined) { | |
|     // Default to true | |
|     redefine = true | |
|   } | |
| 
 | |
|   Object.getOwnPropertyNames(src).forEach(function forEachOwnPropertyName (name) { | |
|     if (!redefine && hasOwnProperty.call(dest, name)) { | |
|       // Skip descriptor | |
|       return | |
|     } | |
| 
 | |
|     // Copy descriptor | |
|     var descriptor = Object.getOwnPropertyDescriptor(src, name) | |
|     Object.defineProperty(dest, name, descriptor) | |
|   }) | |
| 
 | |
|   return dest | |
| }
 |