systrace/catapult/third_party/polymer/components/promise-polyfill/Promise-Statics.js

/**
@license
Copyright (c) 2016 The Polymer Project Authors. All rights reserved.
This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
Code distributed by Google as part of the polymer project is also
subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
*/
Promise.all = Promise.all || function () {
  var args = Array.prototype.slice.call(arguments.length === 1 && Array.isArray(arguments[0]) ? arguments[0] : arguments);

  return new Promise(function (resolve, reject) {
    if (args.length === 0) return resolve([]);
    var remaining = args.length;
    function res(i, val) {
      try {
        if (val && (typeof val === 'object' || typeof val === 'function')) {
          var then = val.then;
          if (typeof then === 'function') {
            then.call(val, function (val) { res(i, val) }, reject);
            return;
          }
        }
        args[i] = val;
        if (--remaining === 0) {
          resolve(args);
        }
      } catch (ex) {
        reject(ex);
      }
    }
    for (var i = 0; i < args.length; i++) {
      res(i, args[i]);
    }
  });
};

Promise.race = Promise.race || function(values) {
  // TODO(bradfordcsmith): To be consistent with the ECMAScript spec, this
  //     method should take any iterable, not just an array.
  var forcedArray = /** @type {!Array<!Thenable>} */ (values);
  return new Promise(function (resolve, reject) {
    for(var i = 0, len = forcedArray.length; i < len; i++) {
      forcedArray[i].then(resolve, reject);
    }
  });
};