# File lib/cucumber/formatter/usage.rb, line 119
      def add_unused_stepdefs
        @step_mother.unmatched_step_definitions.each do |step_definition|
          stepdef_key = StepDefKey.new(step_definition.regexp_source, step_definition.file_colon_line)
          @stepdef_to_match[stepdef_key] = []
        end
      end