selenium-webdriver/testing/index.js

The official WebDriver JavaScript bindings from the Selenium project

// Copyright 2013 Selenium committers
// Copyright 2013 Software Freedom Conservancy
//
// 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.

/**
 * @fileoverview Provides wrappers around the following global functions from
 * Mocha's BDD interface:
 *     after
 *     afterEach
 *     before
 *     beforeEach
 *     it
 *     it.only
 *     it.skip
 *     xit
 *
 * The provided wrappers leverage the webdriver.promise.ControlFlow to simplify
 * writing asynchronous tests:
 *
 * var webdriver = require('selenium-webdriver'),
 *     remote = require('selenium-webdriver/remote'),
 *     test = require('selenium-webdriver/testing');
 *
 * test.describe('Google Search', function() {
 *   var driver, server;
 *
 *   test.before(function() {
 *     server = new remote.SeleniumServer({
 *       jar: 'path/to/selenium-server-standalone.jar'
 *     });
 *     server.start();
 *
 *     driver = new webdriver.Builder().
 *         withCapabilities({'browserName': 'firefox'}).
 *         usingServer(server.address()).
 *         build();
 *   });
 *
 *   test.after(function() {
 *     driver.quit();
 *     server.stop();
 *   });
 *
 *   test.it('should append query to title', function() {
 *     driver.get('http://www.google.com');
 *     driver.findElement(webdriver.By.name('q')).sendKeys('webdriver');
 *     driver.findElement(webdriver.By.name('btnG')).click();
 *     driver.wait(function() {
 *       return driver.getTitle().then(function(title) {
 *         return 'webdriver - Google Search' === title;
 *       });
 *     }, 1000, 'Waiting for title to update');
 *   });
 * });
 *
 * You may conditionally suppress a test function using the exported
 * "ignore" function. If the provided predicate returns true, the attached
 * test case will be skipped:
 *
 *   test.ignore(maybe()).it('is flaky', function() {
 *     if (Math.random() < 0.5) throw Error();
 *   });
 *
 *   function maybe() { return Math.random() < 0.5; }
 */

var flow = require('..').promise.controlFlow();


/**
 * Wraps a function so that all passed arguments are ignored.
 * @param {!Function} fn The function to wrap.
 * @return {!Function} The wrapped function.
 */
function seal(fn) {
  return function() {
    fn();
  };
}


/**
 * Wraps a function on Mocha's BDD interface so it runs inside a
 * webdriver.promise.ControlFlow and waits for the flow to complete before
 * continuing.
 * @param {!Function} globalFn The function to wrap.
 * @return {!Function} The new function.
 */
function wrapped(globalFn) {
  return function() {
    switch (arguments.length) {
      case 1:
        globalFn(asyncTestFn(arguments[0]));
        break;

      case 2:
        globalFn(arguments[0], asyncTestFn(arguments[1]));
        break;

      default:
        throw Error('Invalid # arguments: ' + arguments.length);
    }
  };

  function asyncTestFn(fn) {
    return function(done) {
      this.timeout(0);
      flow.execute(fn).then(seal(done), done);
    };
  }
}


/**
 * Ignores the test chained to this function if the provided predicate returns
 * true.
 * @param {function(): boolean} predicateFn A predicate to call to determine
 *     if the test should be suppressed. This function MUST be synchronous.
 * @return {!Object} An object with wrapped versions of exports.it and
 *     exports.describe that ignore tests as indicated by the predicate.
 */
function ignore(predicateFn) {
  var describe = wrap(exports.xdescribe, exports.describe);
  describe.only = wrap(exports.xdescribe, exports.describe.only);

  var it = wrap(exports.xit, exports.it);
  it.only = wrap(exports.xit, exports.it.only);

  return {
    describe: describe,
    it: it
  };

  function wrap(onSkip, onRun) {
    return function(title, fn) {
      if (predicateFn()) {
        onSkip(title, fn);
      } else {
        onRun(title, fn);
      }
    };
  }
}


// PUBLIC API


exports.describe = global.describe;
exports.xdescribe = global.xdescribe;
exports.describe.skip = global.describe.skip;

exports.after = wrapped(global.after);
exports.afterEach = wrapped(global.afterEach);
exports.before = wrapped(global.before);
exports.beforeEach = wrapped(global.beforeEach);

exports.it = wrapped(global.it);
exports.it.only = exports.iit = wrapped(global.it.only);
exports.it.skip = exports.xit = wrapped(global.xit);

exports.ignore = ignore;