☕ Run Mocha tests using headless Google Chrome
To begin, you'll need to install mocha-chrome
:
$ npm install mocha-chrome --save-dev
Then you'll need a local npm install of mocha:
$ npm install mocha --save-dev
To run the tests, you'll need an HTML file with some basics:
<!doctype>
<html>
<head>
<title>Test</title>
<meta charset="utf-8">
<link rel="stylesheet" href="../../node_modules/mocha/mocha.css" />
<script src="../../node_modules/mocha/mocha.js"></script>
<script src="../../node_modules/chai/chai.js"></script>
</head>
<body>
<div id="mocha"></div>
<script>
expect = chai.expect;
// add tests here
mocha.run();
</script>
</body>
</html>
You can then add your tests either through an external script file or
inline within a <script>
tag. Running the tests is easy, either with the CLI
binary, or programmatically.
$ mocha-chrome --help
Usage
$ mocha-chrome <file.html> [options]
Options
--mocha A JSON string representing a config object to pass to Mocha
--log-level Specify a log level; trace, debug, info, warn, error
--no-colors Disable colors in Mocha's output
--reporter Specify the Mocha reporter to use
--timeout Specify the test startup timeout to use
Examples
$ mocha-chrome test.html --no-colors
$ mocha-chrome test.html --reporter dot
$ mocha-chrome test.html --mocha '{"ui":"tdd"}'
mocha-chrome
is technically an event emitter. Due to the asynchronous nature of
nearly every interaction with headless Chrome, a simple event bus is used to
handle actions from the browser. You have access to those events if running
mocha-chrome
programatically.
Example usage can be found in both test.js and bin/mocha-chrome.
Fired to indicate that mocha-chrome
should configure mocha.
Fired when all tests have ended.
stats
: object
- A Mocha stats object. eg:
{
suites: 1,
tests: 1,
passes: 1,
pending: 0,
failures: 0,
start: '2017-08-03T02:12:02.007Z',
end: '2017-08-03T02:12:02.017Z',
duration: 10
}
Fired to indicate that the mocha script in the client has been loaded.
Fired when a resource fails to load.
data
: object
- An object containing information about the resource. eg:
{ url, method, reason }
Fired when a resource fails to load.
tests
: number
- The number of tests being run.
Fired to indicate that mocha-chrome
should inform mocha of the width of
the current console/terminal.
Reporters are limited to those which don't use process.stdout.write
to manipulate
terminal output. eg. spec
, xunit
, etc. Examples of reporters which don't presently
produce expected output formatting include dot
and nyan
. The cause of this
limitation is the lack of a good means to pipe Mocha's built-in stdout.write
through the Chrome Devtools Protocol to mocha-chrome
.
Third party reporters are currently supported, but support is planned. Contributoion on that effort is of course welcome.
Please refer to the "Running it all on Travis CI" portion of the guide on Automated testing with Headless Chrome from Google. Though the article primarily addresses Karma, the setup for Travis CI is identical.
$ npm test
Yep, that's it.
We welcome your contributions! Please have a read of CONTRIBUTING.
I'd like to thank @nathanboktae for his work on mocha-phantomjs
and mocha-phantomjs-core;
two projects I've used extensively over the years, and from which the inspiration
for this module originates. Many of the nuances of working with mocha in a hosted
or connected browser environment were solved within mocha-phantomjs-core
and I
am personally grateful.