axe-core/build/tasks/test-webdriver.js

Accessibility engine for automated Web UI testing

/*global window */
/*eslint 
max-statements: ["error", 20],
*/
'use strict';

var Promise = require('promise');
var WebDriver = require('selenium-webdriver');


module.exports = function (grunt) {

	/**
	 * Keep injecting scripts until window.mochaResults is set
	 */
	function collectTestResults(driver) {

		// inject a script that waits half a second
		return driver.executeAsyncScript(function () {
			var callback = arguments[arguments.length - 1];
			setTimeout(function () {
				// return the mocha results (or undefined if not finished)
				callback(window.mochaResults);
			}, 500);

		}).then(function (result) {
			// If there are no results, listen a little longer
			if (!result) {
				return collectTestResults(driver);

				// if there are, return them
			} else {
				return Promise.resolve(result);
			}
		});
	}

	/**
	 * Test each URL
	 */
	function runTestUrls(driver, isMobile, urls, errors) {
		var url = urls.shift();
		errors = errors || [];

		// Give each page enough time
		driver.manage().timeouts().setScriptTimeout(!isMobile ? 60000 * 5 : (60000 * 10));

		return driver.get(url)
			// Get results
			.then(function () {
				return collectTestResults(driver);
			})
			// And process them
			.then(function (result) {
				grunt.log.writeln(url);

				// Remember the errors
				(result.reports || []).forEach(function (err) {
					grunt.log.error(err.message);
					err.url = url;
					errors.push(err);
				});

				// Log the result of the page tests
				grunt.log[(result.failures ? 'error' : 'ok')](
					'passes: ' + result.passes + ', ' +
					'failures: ' + result.failures + ', ' +
					'duration: ' + (result.duration / 1000) + 's'
				);
				grunt.log.writeln();

			}).then(function () {
				// Start the next job, if any
				if (urls.length > 0) {
					return runTestUrls(driver, isMobile, urls, errors);
				} else {
					driver.quit();
					return Promise.resolve(errors);
				}
			});
	}

	/*
	* Build web driver depends whether REMOTE_SELENIUM_URL is set
	*/
	function buildWebDriver(browser) {
		var webdriver,
			capabilities;
		var mobileBrowser = browser.split('-mobile');
		if (mobileBrowser.length > 1) {
			browser = mobileBrowser[0];
			capabilities = {
				browserName: mobileBrowser[0],
				chromeOptions: {
					mobileEmulation: {
						deviceMetrics: {
							width: 320,
							height: 568,
							pixelRatio: 2
						}
					}
				}
			};
		}

		if (process.env.REMOTE_SELENIUM_URL) {
			webdriver = new WebDriver.Builder()
				.forBrowser(browser)
				.withCapabilities(capabilities)
				.usingServer(process.env.REMOTE_SELENIUM_URL)
				.build();
		} else {
			webdriver = new WebDriver.Builder()
				.withCapabilities(capabilities)
				.forBrowser(browser)
				.build();
		}

		return {
			driver: webdriver,
			isMobile: (mobileBrowser.length > 1)
		};
	}

	/**
	 * Run all tests in a browser using webdriver
	 */
	grunt.registerMultiTask('test-webdriver',
		'Task for launching Webdriver with options and running tests against options URLs',
		function () {
			var driver;
			var isMobile = false;
			var done = this.async();
			var options = this.options({
				browser: 'firefox'
			});
			// yes, really, and this isn't documented anywhere either.
			options.browser = (options.browser === 'edge') ? 'MicrosoftEdge' : options.browser;


			if ((process.platform === 'win32' && options.browser === 'safari') ||
				(process.platform === 'darwin' && ['ie', 'MicrosoftEdge'].indexOf(options.browser) !== -1) ||
				((process.platform === 'linux' || process.env.REMOTE_SELENIUM_URL) &&
					['ie', 'MicrosoftEdge', 'safari'].indexOf(options.browser) !== -1)
			) {
				grunt.log.writeln();
				grunt.log.writeln('Skipped ' + options.browser + ' as it is not supported on this platform');
				return done();
			}

			// try to load the browser
			try {
				var webDriver = buildWebDriver(options.browser);
				driver = webDriver.driver;
				isMobile = webDriver.isMobile;
				// If load fails, warn user and move to the next task
			} catch (err) {
				grunt.log.writeln();
				grunt.log.error(err.message);
				grunt.log.writeln('Aborted testing using ' + options.browser);
				return done();
			}

			// Test all pages
			runTestUrls(driver, isMobile, options.urls)
				.then(function (testErrors) {
					// log each error and abort
					testErrors.forEach(function (err) {
						grunt.log.writeln();
						grunt.log.error('URL: ' + err.url);
						grunt.log.error('Describe: ' + err.titles.join(' > '));
						grunt.log.error('it ' + err.name);
						grunt.log.error(err.stack);
						grunt.log.writeln();
					});

					// Return the success to Grunt
					done(testErrors.length === 0);

					// catch any potential problems
				}).catch(function (err) {
					grunt.log.error(err);
					done(false);
				});

		}
	);
};