Minitest::Metz

Minitest::Metz is a Minitest plugin that under it's hood hides the SandiMeter. It allows you to easily apply Sandi Metz's four rules for developers on your tests.

Because tests are code. Especially in Minitest, where each test file is a subclass of Minitest::Test.

Add this line to your application's Gemfile:

gem 'minitest-metz'

And then execute:

$ bundle

Or install it yourself as:

$ gem install minitest-metz

There two ways that you can use this plugin:

You can apply the --metz flag when you are running your tests. If present, the plugin will run the sandi_meter for the test that ran.

If you are willing of writing tests around the four rules, you can assert on them. The assertions works on basically any type of class, whether it is a test class or a production class. If you want to test the test class for the four rules:

class PersonTest < Minitest::Test
  def test_sandi_four_rules
    assert_obey_metz(self.class)
    # Or..
    assert_obey_metz(PersonTest)
  end
end

If you want to test another class:

class PersonTest < Minitest::Test
  def test_sandi_four_rules
    assert_obey_metz(Person)
  end
end

Also, there's the option on asserting on a file path:

class PersonTest < Minitest::Test
  def test_sandi_four_rules
    assert_obey_metz("lib/person/person.rb")
  end
end

And, of course, you can use refute_obey_metz, although I have no idea why would you. But anyway, it's available for use. Have fun.

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/fteem/minitest-metz.