Nice new edge feature: test/do declaration style testing

Posted by Jonathan

Rails 2 introduced ActiveSupport::TestCase and friends, RoR's enhancement of Test::Unit.

Those extra classes made testing Rails controllers easier and removed the need for cluttered setup methods. Today DHH committed a new feature to ActiveSupport::TestCase (by Jay Fields) that allows Rails tests to match up with RSpec's and Shoulda's nicer declaration style test naming: test/do declaration style testing.

In plain Test::Unit each test would be a method named 'test_' followed by the name the test: 

def test_email_format_is_validated
  ...
end

def test_invalid_credit_card_number_throws_exception
  ...
end

This works ok but is a bit clumsy and gets ugly with long method names. In edge you can now write the test like this 

test 'email format is validated' do
  ...
end

test 'invalid credit card number throws exception' do
  ...
end

What happens in the background is that ActiveSupport::TestCase will just generate the test_email_format_is_validated method for you. What is missing is a nice integration with the test runner.

This brings Rails developers that envy RSpec's and Shoulda's declarative style to the same level. RSpec&co can still do more tricks but most developers I know really just lust for the it 'should do as I want it to' do ... end syntax and don't really care about the a.should == b.