| // 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. |
| |
| var util = require('util'); |
| var events = require('events'); |
| var helpers = require('../helpers/helpers.js'); |
| |
| /* |
| * This custom command allows us to locate an HTML element on the page and then wait until the value of a specified |
| * attribute matches the provided expression (aka. the 'checker' function). It retries executing the checker function |
| * every 100ms until either it evaluates to true or it reaches maxTimeInMilliseconds (which fails the test). |
| * Nightwatch uses the Node.js EventEmitter pattern to handle asynchronous code so this command is also an EventEmitter. |
| */ |
| |
| function WaitForAttribute() { |
| events.EventEmitter.call(this); |
| this.startTimeInMilliseconds = null; |
| } |
| |
| util.inherits(WaitForAttribute, events.EventEmitter); |
| |
| WaitForAttribute.prototype.command = function (element, attribute, checker, timeoutInMilliseconds) { |
| this.startTimeInMilliseconds = new Date().getTime(); |
| var self = this; |
| var message; |
| |
| if (typeof timeoutInMilliseconds !== 'number') { |
| timeoutInMilliseconds = helpers.maxWaitTime; |
| } |
| |
| this.check(element, attribute, checker, function (result, loadedTimeInMilliseconds) { |
| if (result) { |
| message = 'waitForAttribute: ' + element + '@' + attribute + '. Expression was true after ' + (loadedTimeInMilliseconds - self.startTimeInMilliseconds) + ' ms.'; |
| } else { |
| message = 'waitForAttribute: ' + element + '@' + attribute + '. Expression wasn\'t true in ' + timeoutInMilliseconds + ' ms.'; |
| } |
| self.client.assertion(result, 'expression false', 'expression true', message, true); |
| self.emit('complete'); |
| }, timeoutInMilliseconds); |
| |
| return this; |
| }; |
| |
| WaitForAttribute.prototype.check = function (element, attribute, checker, callback, maxTimeInMilliseconds) { |
| var self = this; |
| |
| this.api.getAttribute(element, attribute, function (result) { |
| var now = new Date().getTime(); |
| if (result.status === 0 && checker(result.value)) { |
| callback(true, now); |
| } else if (now - self.startTimeInMilliseconds < maxTimeInMilliseconds) { |
| setTimeout(function () { |
| self.check(element, attribute, checker, callback, maxTimeInMilliseconds); |
| }, 100); |
| } else { |
| callback(false); |
| } |
| }); |
| }; |
| |
| module.exports = WaitForAttribute; |