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Mocha Selenium

Everything you need for selenium testing in node.js.

There are two parts: the library and the runner.

The library provides you with the setup() function which returns a driver that is instrumented to make your tests simple, semantic, and easy to use. Among other things, it is automatically initialized in a before() clause, destroyed in an after() clause, and will even fire up an instance of your app & a webdriver server if you need them!

The runner is configured with a selenium.json file, and will run your mocha test files in series or in parallel, for any number of browsers. Installing it with npm install -g mocha-selenium will give you the mocha-selenium command on your path.

The Library

Has a bunch of options. Some of the options are default to ENV variables if they are present. Read the docs for a thorough description.

Optionally if you are using the promise webdriver or promiseChain webdriver supported by wd, you can pass a webdriverType to the setup options object. You can use either 'promise' or 'promiseChain' as the string, if not passed the default webdriver will be used.

Here's an example:

var expect = require('expect.js')
  , b = require('mocha-selenium').setup("Login Page", {
      appDir: path.dirname(__dirname),
      lastShot: "failed",
      webdriverType: 'promiseChain'  // OPTIONAL

describe('The login page', function () {
  this.timeout(20 * 1000)
  before(function (done) {
    b.get(b.baseUrl + '/login', done)
  it('should work', function (done) {
    function fail(err) {
    b.chain({onError: fail})
     .fillInForm('.loginForm', {
       username: 'jsmith',
       password: '1830'
     .clickByCss('.loginForm button.submit')
     // make sure we were redirected to the account page
     .url(function (err, url) {
       if (err) return fail(err)

Convenience functions added to the driver

In addition to the normal wd methods, there are the following:

General Methods

ensureCookie(name, value, done(err))

On the current page, if the cookie by the name of name with value value does not exist, set the cookie and refresh the page.

If value is a function, it is called with the current value of the cookie. If it returns a value other than the current cookie value, the cookie is set to that value.

fillInForm(data, [formSelector,] done(err))

Data is a map of "input name": "value to type". If formSelector is given, only inputs that are children of the given selector will be filled in. Otherwise, the first input in the document with the given name will be populated.

rel(url, done(err))

= b.get(b.baseUrl + url, done).

Element-specific methods

The following suffixes are available for these methods, mirroring the wd library:

ByClassName, ByCssSelector, ById, ByName, ByLinkText, ByPartialLinkText, ByTagName, ByXPath, ByCss.

I will use the ByCss suffix for demonstration.

  • textByCss(selector, done(err, text, element))
  • visibleByCss(selector, done(err, isVisible, element))
  • valueByCss(selector, done(err, value, element))
  • clickByCss(selector, done(err, element))
  • waitAndGet(selector, timeout, done(err, element))
  • waitAndClickByCss(selector, timeout, done(err, element))

The Runner

Run your mocha selenium tests in parallel in mutliple browsers.


  Usage: mocha-selenium [options]


    -h, --help               output usage information
    -V, --version            output the version number
    -e, --environment [env]  Pick the environment to run (host + browsers). Default: local
    -p, --parallel           Run the tests in parallel. Default: false
    -c, --config [file]      Specify the config file. Default: ./selenium.json
  files: // filename or glob, or list of filenames or globs
  envs: { // a map of [envname] to an environment definition.
    local: [browserdef, ...] OR {
      browsers: [browserdef, ...],
      inherits: // name or list of names of other environemnts. Their
                // browserdefs will be appended to the current env.
      // if no hostname is given, mocha-selenium will start its own
      // selenium drivers. Currently phantomjs and chrome are supported
      hostname: "",
      port: 80,
      auth: {
        type: 'plain',
        username: 'MyName',
        password: 'secret'
      } OR {
        type: 'env', // the username and password are environmental variables
        username: 'SAUCE_USERNAME',
        password: 'SAUCE_ACCESS_KEY'
    otherenv: ...,


["browsername", "version", "platform"]

["internet explorer", "8", "Windows XP"]
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