Riot: Ruby Unit Testing

Riot is a Ruby unit testing framework. It results in terse and expressive unit tests. It strikes the perfect balance between shoulda and rspec–like test frameworks. It’s also very fast.

Riot isn’t based on Test::Unit (unlike Shoulda). It flattens your tests into contexts with sets of assertions. It has a setup block that runs before the assertions in a context.

There’s a movement within the Ruby community to write tests with one assertion per test block. Riot fundamentally works this way because assertions are the test block, so cheating isn’t possible. This makes for incredibly focused unit tests.

Riot is still under active development by its author, Justin Knowlden, but it’s completely usable right now. I was so impressed by it that I’ve created a JavaScript port called riotjs — I’ll cover this in another post soon.

Redundancy

Used as the author intended, Riot removes redundancy even when compared to Shoulda.

Test::Unit:

class UserTest < Test::Unit::TestCase
  def setup
    @user = User.new
  end

  def test_email_address_is_nil
    assert_nil @user.email
  end
end

Shoulda:

class UserTest < Test::Unit::TestCase
  def setup
    @user = User.new
  end

  should "have nil email" { assert_nil @user.email }
end

Riot:

context "a new user" do
  setup { User.new }
  asserts("email address") { topic.email }.nil
end

FAQ and More

Riot’s author has anticipated the typical set of Ruby test tool questions in the README.