Grunt and Testacular


Testacular is a test runner for running browser tests. Once you have it up and running, you may want to integrate it with your Grunt build process. This will allow Testacular to be started and your tests to be run from Grunt.

grunt-testacular

Lucky for us, Friedel Ziegelmayer has created a nice little plugin, grunt-testacular.

To install:

$ npm install grunt-testacular

Add the current version to your package.json for the future:

"grunt-testacular": "0.2.x"

Import the plugin in your grunt.js file:

grunt.loadNpmTasks('grunt-testacular');

And finally, in grunt.js, specify your tasks:

testacularServer: {
  unit: {
    options: {
      keepalive: true
    },
    configFile: 'testacular.conf.js'
  }
},
testacularRun: {
  unit: {
    runnerPort: 9100
  }
}

Two Tasks

Grunt-testacular provides two tasks:

  1. testacularServer - starts the Testacular server (equivalent to testacular start)
  2. testacularRun - runs your tests against an already-started server (equivalent to testacular run)

A grunt-testacular Oddity

If you don't have keepalive: true set for grunt-testacular, the Testacular server will shutdown before it has a chance to capture browsers or run your tests. I'm really not sure why this is even an option. The false case behavior doesn't seem to be useful. With the singleRun ability of Testacular, the plugin should just call start on the server and let the server configuration decide when it's appropriate to shut down.

Update: I logged an issue for grunt-testacular that Grunt tasks listed after testacularServer weren't being run. Friedal responded that keepalive: true was the problem. If it is specified true, then it has to be the last task in the list. So, if you have tasks after testacularServer specified, remove keepalive: true and add watch to the end of your task list.

Grunt and Testacular Work Flow

Of course, your work flow is up to you, and Grunt and Testacular give you enough flexibility to decide your own, but I think you'll run your tests in two main scenarios: development and continuous integration.

Development

For development, I like to start up the Testacular server and keep it running. Then, I go write tests and update source code. Testacular will notice my changes and automatically re-run my tests.

To set this up, make sure your grunt-testacular task has this option:

keepalive: true

This will keep the server up even after the tests have completed.

And make sure your testacular.conf.js file includes:

autoWatch = true;

This will force Testacular to re-run your tests if anything in your source or tests change (specifically, if anything in testacular.conf.js's files array changes).

Continuous Integration

For continuous integration, you just want your automated build to be able to verify the source code integrity prior to deploying.

We don't want tests to re-run automatically based on our changes, so we turn off autoWatch in testacular.conf.js:

autoWatch = false;

And we set one more value in testacular.conf.js to:

singleRun = true;

This will allow the testacularServer task to be run once, have Testacular run all the tests, and then make the server shut down.

Finally, remember to keep keepalive: true set in grunt.js. Odd, right?

Multiple Testacular Configurations

To manage the options that are distinct to these two work flows, one could just create two separate testacular.conf.js files. But, that would be overkill, because there'd be a lot of overlap between the two files.

Instead, the grunt-testacular plugin gives you override ability on a per-variable basis. To support the development and integration scenario, the grunt multiTask might look like this:

testacularServer: {
  unit: {
    options: {
      keepalive: true
    },
    configFile: 'testacular.conf.js'
  },
  integration: {
    options: {
      keepalive: true
    },
    configFile: 'testacular.conf.js',
    autoWatch: false,
    singleRun: true
  }
}

Following this same pattern, you could create a separate config for automated functional or end-to-end tests as well.

Note that the options object is strictly for the plugin. The other variables at that level feed straight into Testacular as overrides.

Integrated Testing

Process and product maturity are increased as tests are integrated into the build process. Grunt and Testacular make integrating your browser tests a snap.