jasmine-rails gem

This project is intended to make it a little easier to integrate Jasmine into your workflow, particularly if you're working in Rails 3.1 or later. (If you're on earlier versions of Rails, I'd suggest directly using the combination of Pivotal's jasmine gem and jasmine-headless-webkit.)

By bundling this gem and configuring your project, you can expect to:

  • Be able to run Jasmine specs from the command line (and fast) with John Bintz's excellent jasmine-headless-webkit
  • Be able to run Jasmine specs in a browser (wherever you choose to mount the jasmine-rails engine)
  • Write specs or source in CoffeeScript, leveraging the asset pipeline to pre-process it

Prerequisites

Install qt for its headless webkit widget. The easiest way (on a Mac) that I've found is to use homebrew:

brew install qt

For help installing the qt libs on other platforms, the I'd recommend perusing capybara-webkit driver's documentation, becuse it has the same dependency.

Adding the gem

Add jasmine-rails to your Gemfile, like so

group :test, :development do
  gem 'jasmine-rails'
end

Next, run bundle install.

Now, we'll use the jasmine gem to initialize a jasmine.yml configuration file:

bundle exec jasmine init

And remove some files the jasmine gem creates that you won't need:

rm public/javascripts/Player.js public/javascripts/Song.js spec/javascripts/PlayerSpec.js spec/javascripts/helpers/SpecHelper.js lib/tasks/jasmine.rake

Next, edit the generated spec/javascripts/support/jasmine.yml file to ensure that it will find all your JavaScript sources and specs. The default file is written for Rails <3.1 so it doesn't know about the asset directories. As an example, mine looks like this:

src_files:
  - "vendor/**/*.{js,coffee}"
  - "lib/**/*.{js,coffee}"
  - "app/**/*.{js,coffee}"

stylesheets:
  - "vendor/**/*.css"
  - "lib/**/*.css"
  - "app/**/*.css"

helpers:
  - "helpers/**/*.{js,coffee}"

spec_files:
  - "**/*[Ss]pec.{js,coffee}"

src_dir:

spec_dir: spec/javascripts

Running from the command line

If you were to run:

bundle exec jasmine-headless-webkit --color

You'd hopefully see something like:

Running Jasmine specs...

PASS: 0 tests, 0 failures, 0.001 secs.

I encourage you to explore John Bintz's excellent jasmine-headless-webkit's documentation for more ideas, like creating a Rake task or running it on a display-less CI server.

If you experience an error at this point, the most likely cause is JavaScript being loaded out of order, or otherwise conflicting with other existing JavaScript in your project. See "Debugging" below.

Running from your browser

Just mount jasmine-rails by adding something like this to your routes.rb:

mount JasmineRails::Engine => "/specs" unless Rails.env.production?

Now when you run bundle exec rails s, and navigate to http://localhost:3000/specs, you should see a Jasmine spec runner in your browser.

Debugging

In your browser

In my workflow, I like to work with specs in the command line until I hit a snag and could benefit from debugging in Web Inspector or Firebug to figure out what's going on.

When debugging, I append the query param "debug_assets=true" like so: http://localhost:3000/specs?debug_assets=true.

This is telling the asset pipeline to include each of your scripts in individual <script> tags. Seeing each script loaded separately makes debugging much easier for me.

From the command line

Even though they both read from the same config file, it's certainly possible that your specs will pass in the browser and fail from the command line. In this case, you can try to debug or analyze what's going on by using the "--keep" flag from jasmine-headless-webkit.

By running:

bundle exec jasmine-headless-webkit --keep

If the tests fail, jasmine-headless-webkit will leave its generated spec runner HTML file persisted in your rails root folder. It'll be named something like "specrunner.48160.html".

Guard

Guard is a great tool for triggering spec runs when files change. To use it, you can bundle these gems:

group :test, :development do
  ...      
  gem 'guard-rails-assets'
  gem 'guard-jasmine-headless-webkit'
  ...
end

In my Guardfile, this configuration is working well for me:

guard 'rails-assets' do
  watch(%r{^.*/assets/.+$})
  watch('config/application.rb')
end

spec_location = "spec/javascripts/%s_spec"

guard 'jasmine-headless-webkit' do
  watch(%r{^app/views/.*\.jst$})
  watch(%r{^public/javascripts/(.*)\.js$}) { |m| newest_js_file(spec_location % m[1]) }
  watch(%r{^.*/assets/javascripts/(.*)\.(js|coffee)$}) { |m| newest_js_file(spec_location % m[1]) }
  watch(%r{^spec/javascripts/(.*)_spec\..*}) { |m| newest_js_file(spec_location % m[1]) }
end

Finally, to run guard, just:

bundle exec guard