Shoulda - Making tests easy on the fingers and eyes

Shoulda makes it easy to write elegant, understandable, and maintainable tests. Shoulda consists of matchers, test helpers, and assertions. It’s fully compatible with your existing tests in Test::Unit or RSpec, and requires no retooling to use.

Matchers: Test::Unit- and RSpec-compatible one-liners that test common Rails functionality. These tests would otherwise be much longer, more complex, and error-prone.
Helpers: #context and #should give you RSpec like test blocks in Test::Unit. In addition, you get nested contexts and a much more readable syntax.
Assertions: Many common Rails testing idioms have been distilled into a set of useful assertions.

Usage

ActiveRecord Tests (Shoulda::ActiveRecord::Matchers)

Test your ActiveRecord associations and validations with these powerful matchers:

class PostTest < Test::Unit::TestCase
  should belong_to(:user)
  should have_many(:tags).through(:taggings)

  should validate_uniqueness_of(:title)
  should validate_presence_of(:body).with_message(/wtf/)
  should validate_presence_of(:title)
  should validate_numericality_of(:user_id)
end

class UserTest < Test::Unit::TestCase
  should have_many(:posts)

  should_not allow_value("blah").for(:email)
  should_not allow_value("b lah").for(:email)
  should allow_value("[email protected]").for(:email)
  should allow_value("[email protected]").for(:email)
  should ensure_inclusion_of(:email).in_range(1..100)
  should ensure_inclusion_of(:age).in_range(1..100)
  should_not allow_mass_assignment_of(:password)
end

Makes TDD so much easier.

Controller Tests (Shoulda::Controller::Matchers)

Matchers to test the most common controller patterns…

class PostsControllerTest < ActionController::TestCase
  context "on GET to :show for first record" do
    setup do
      get :show, :id => 1
    end

    should assign_to(:user)
    should respond_with(:success)
    should render_template(:show)
    should_not set_the_flash

    should "do something else really cool" do
      assert_equal 1, assigns(:user).id
    end
  end
end

Context Helpers (Shoulda::Context)

Stop killing your fingers with all of those underscores… Name your tests with plain sentences!

class UserTest < Test::Unit::TestCase
  context "A User instance" do
    setup do
      @user = User.find(:first)
    end

    should "return its full name" do
      assert_equal 'John Doe', @user.full_name
    end

    context "with a profile" do
      setup do
        @user.profile = Profile.find(:first)
      end

      should "return true when sent #has_profile?" do
        assert @user.has_profile?
      end
    end
  end
end

Produces the following test methods:

"test: A User instance should return its full name."
"test: A User instance with a profile should return true when sent #has_profile?."

So readable!

Helpful Assertions (Shoulda::Assertions)

More to come here, but have fun with what’s there.

assert_same_elements([:a, :b, :c], [:c, :a, :b])
assert_contains(['a', '1'], /\d/)
assert_contains(['a', '1'], 'a')

Rails Installation (Test::Unit)

Specify the gem dependency in your config/environment.rb file:

Rails::Initializer.run do |config|
  config.gem "shoulda", :lib => "shoulda"
end

Then:

$ rake gems:install
$ rake gems:unpack

Rails Installation (RSpec)

If you’re using Shoulda with RSpec, we recommend that you add config.gem lines for RSpec and Shoulda in your config/environment/test.rb file, but do not ask Rails to load the RSpec and Shoulda libraries:

config.gem 'rspec',       :lib => false
config.gem 'rspec-rails', :lib => false
config.gem 'shoulda',     :lib => false

Then require shoulda from your spec/spec_helper.rb file, before Spec::Runner is configured:

# requires for RSpec
require 'shoulda'
Spec::Runner.configure do |config|
# ...

You should not need to require anything besides the top-level shoulda library.

Rails 3 Installation (RSpec)

With Rails 3 and Bundler, requiring Shoulda is as easy as adding it to your Gemfile:

group :test do
  gem "shoulda"
  gem "rspec-rails", "2.0.0.beta.12"
end

Shoulda will automatically include matchers into the appropriate example groups.

Credits

Shoulda is maintained and funded by thougthbot