Testing Suite for jRuby on Rails with RSpec

It took me some time to figure out how to setup a performant testing environment in Rails 3 when using jRuby in my development environment. Therefore, I bring you a tutorial on how to setup my testing environment to hopefully save you time if you must also go down this path. I have chosen to use the following tools in my testing environment: Rspec for BDD, Spork to decrease loading time of Rails and decrease the time it takes to run RSpec tests, ZenTest for auto-testing, and Nailgun to decrease the time to load the JVM.

A few things to note

A few things to note before starting this tutorial are as follows. Whenever you see the character "$" this denotes a terminal command. Type the command following the "$" into terminal to execute the command. Also, my text editor of choice is Textmate, so if you see "mate" in a command replace it with whatever your editor of choice is. One last note before we start. I use "..." or the vertical form of "..." to represent additional code pre existing above.

This tutorial assumes you are using jruby with RVM. If you are not using RVM for your jruby installation you need to use "jruby -S" instead of "ruby" when executing commands as well as prefix "gem install" with "jruby -S". For example, "jruby -S gem install ZenTest".

I highly recommend using RVM. If you would like information on how to install RVM, as well as using RVM to install jruby checkout one of my previous posts Install jRuby on Rails with RVM

Step 1 :: Install RSpec

RSpec is a Behaviour-Driven Development tool for Ruby programmers. RSpec provides clean and readable self documenting tests.

Create app without tests

$ rails new demo -T

Edit Gemfile

$ mate Gemfile

group :development do
    gem 'rspec-rails', '2.5.0'
group :test do
    gem 'rspec', '2.5.0'

Install rspec for your current Rails project

$ rails generate rspec:install

Step 2 :: Install Spork

Spork will greatly decrease the amount of time it takes to run your rspec tests. Unfortunately it does not work with jruby by default so we will need to grab a special branch of the gem.

Grab jruby version of Spork

$ git clone git://github.com/rdp/spork.git
$ cd spork
$ gem build spork.gemspec
$ gem install spork-0.8.3

Now we want to have rspec utilize spork whenever running RSpec tests.

Edit .rspec

$ mate .rspec

Add the following line to .rspec


Bootstrapping spork will modify RSpec's helpers to use Spork in the current Rails project when RSpec is ran.

Bootstrap spork

$ spork --bootstrap

Spork hacks for Rails 3

Spork will not work with Rails 3, so we need to edit a couple of files in order for it to work.

Edit spec/spec_helper.rb

Spork.prefork do
  # Loading more in this block will cause your tests to run faster. However,
  # if you change any configuration or code from libraries loaded here, you'll
  # need to restart spork for it take effect.
  ENV["RAILS_ENV"] ||= 'test'
  unless defined?(Rails)
    require File.dirname(__FILE__) + "/../config/environment"
  require 'rspec/rails'

  # Requires supporting files with custom matchers and macros, etc,
  # in ./support/ and its subdirectories.
  Dir["#{File.dirname(__FILE__)}/support/**/*.rb"].each {|f| require f}

  Rspec.configure do |config|
    # == Mock Framework
    # If you prefer to use mocha, flexmock or RR, uncomment the appropriate line:
    # config.mock_with :mocha
    # config.mock_with :flexmock
    # config.mock_with :rr
    config.mock_with :rspec

    config.fixture_path = "#{::Rails.root}/spec/fixtures"

    # If you're not using ActiveRecord, or you'd prefer not to run each of your
    # examples within a transaction, comment the following line or assign false
    # instead of true.
    config.use_transactional_fixtures = true

    ### Part of a Spork hack. See http://bit.ly/arY19y
    # Emulate initializer set_clear_dependencies_hook in
    # railties/lib/rails/application/bootstrap.rb

Edit config/application.rb

class Application < Rails::Application
    ### Part of a Spork hack. See http://bit.ly/arY19y
    if Rails.env.test?
      initializer :after => :initialize_dependency_mechanism do
            # Work around initializer in railties/lib/rails/application/bootstrap.rb
            ActiveSupport::Dependencies.mechanism = :load

Step 3 :: Install ZenTest for auto-testing

ZenTest is a gem that will automatically run your test suite when a file change occurs.

Run the following command to install ZenTest

$ gem install ZenTest

To start autotest you must run it from the the root of your Rails project of your dir.

Start autotest

$ autotest

Step 4 :: Bonus: Startup Nailgun

This step is not necessary, but has allowed me to run my tests in under two seconds on my machine.

Nailgun is a server that keeps a JVM open. This minimizes the time our test suite takes to run as the JVM is not required to load whenever we run our tests.

Start the Nailgun server $ ruby --ng-server &

Now that the Nailgun server is running navigate to your Rails project's dir in terminal.

Run RSpec tests using the Nailgun Server

$ ruby --ng rspec spec/

Your tests should now be running significantly faster with the help of nailgun and spork!

Keith Loy

About Keith Loy

An expert in UI engineering specializing in mobile and web development. Deep understanding of javascript and vast experience utilizing javascript to build rich client experiences.

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