Object.es6.js

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @format
 * @polyfill
 */

// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign

if (typeof Object.assign !== 'function') {
  Object.defineProperty(Object, 'assign', {
    value: function assign(target, varArgs) {
      'use strict';
      if (target == null) {
        throw new TypeError('Cannot convert undefined or null to object');
      }

      let to = Object(target);

      for (let index = 1; index < arguments.length; index++) {
        let nextSource = arguments[index];

        if (nextSource != null) {
          for (let nextKey in nextSource) {
            if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
              to[nextKey] = nextSource[nextKey];
            }
          }
        }
      }
      return to;
    },
    writable: true,
    configurable: true,
  });
}