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/*
 * Copyright 2016 The Closure Compiler Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

'require es6/reflect/apply';
'require util/polyfill';


$jscomp.polyfill('Reflect.construct', function(orig) {
  if (orig) return orig;

  /**
   * Polyfill for Reflect.construct() method:
   * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect/construct
   *
   * Calls a constructor as with the 'new' operator.
   * TODO(sdh): how to type 'target' with (new: TARGET) if opt_newTarget missing?
   *
   * @param {function(new: ?, ...?)} target The constructor to call.
   * @param {!Array} argList The arguments as a list.
   * @param {function(new: TARGET, ...?)=} opt_newTarget The constructor to instantiate.
   * @return {TARGET} The result of the function call.
   * @template TARGET
   */
  var polyfill = function(target, argList, opt_newTarget) {
    // if (arguments.length < 3 || opt_newTarget == target) {
    //   return new target(...argList);
    // }
    if (opt_newTarget === undefined) opt_newTarget = target;
    var proto = opt_newTarget.prototype || Object.prototype;
    var obj = Object.create(proto);
    var out = Reflect.apply(target, obj, argList);
    return out || obj;
  };
  return polyfill;
}, 'es6', 'es5'); // ES5: Requires Object.create