Reusing minitest tests via their method names

number_test.rb

class NumberTest < ActiveSupport::TestCase 

  def setup
    @number = 4
  end

  def test_number_is_four
    assert_equal 4, @number
  end

  def test_double_number
    test_number_is_four
    @number = @number * 2
    assert_equal 8, @number
  end

  def test_halfing_number_after_number_is_doubled_returns_it_to_original
    test_double_number
    @number = @number / 2
    test_number_is_four
  end

end

Used in a comment to this blog: http://brandonhilkert.com/blog/7-reasons-why-im-sticking-with-minitest-and-fixtures-in-rails/