| 'use strict'; |
| |
| // modified from https://github.com/es-shims/es6-shim |
| var objectKeys = require('object-keys'); |
| var hasSymbols = require('has-symbols/shams')(); |
| var callBound = require('call-bind/callBound'); |
| var toObject = Object; |
| var $push = callBound('Array.prototype.push'); |
| var $propIsEnumerable = callBound('Object.prototype.propertyIsEnumerable'); |
| var originalGetSymbols = hasSymbols ? Object.getOwnPropertySymbols : null; |
| |
| // eslint-disable-next-line no-unused-vars |
| module.exports = function assign(target, source1) { |
| if (target == null) { throw new TypeError('target must be an object'); } |
| var to = toObject(target); // step 1 |
| if (arguments.length === 1) { |
| return to; // step 2 |
| } |
| for (var s = 1; s < arguments.length; ++s) { |
| var from = toObject(arguments[s]); // step 3.a.i |
| |
| // step 3.a.ii: |
| var keys = objectKeys(from); |
| var getSymbols = hasSymbols && (Object.getOwnPropertySymbols || originalGetSymbols); |
| if (getSymbols) { |
| var syms = getSymbols(from); |
| for (var j = 0; j < syms.length; ++j) { |
| var key = syms[j]; |
| if ($propIsEnumerable(from, key)) { |
| $push(keys, key); |
| } |
| } |
| } |
| |
| // step 3.a.iii: |
| for (var i = 0; i < keys.length; ++i) { |
| var nextKey = keys[i]; |
| if ($propIsEnumerable(from, nextKey)) { // step 3.a.iii.2 |
| var propValue = from[nextKey]; // step 3.a.iii.2.a |
| to[nextKey] = propValue; // step 3.a.iii.2.b |
| } |
| } |
| } |
| |
| return to; // step 4 |
| }; |