def devaluate(actual, expected)
      if actual.include?(expected)
        fail expected_message(actual).to_not_include(expected)
      else
        pass new_message.includes(expected)
      end
    end
def devaluate(actual, expected)
      if actual.include?(expected)
        fail expected_message(actual).to_not_include(expected)
      else
        pass new_message.includes(expected)
      end
    end
(see Riot::AssertionMacro#devaluate)
 @param [Object] expected the object that is not expected to be included