# File lib/simplecov/result.rb, line 47
    def covered_lines
      return @covered_lines if @covered_lines
      @covered_lines = 0
      @files.each do |file|
        original_result[file.filename].each do |line_result|
          @covered_lines += 1 if line_result and line_result > 0
        end
      end
      @covered_lines
    end