# File lib/serverspec/type/file.rb, line 20
      def contain(pattern, from, to)
        if pattern.is_a?(Array)
          backend.check_file_contain_lines(@name, pattern, from, to)
        else
          if (from || to).nil?
            backend.check_file_contain(@name, pattern)
          else
            backend.check_file_contain_within(@name, pattern, from, to)
          end
        end
      end