instance method calculate_directory_statistics

# File railties/lib/rails/code_statistics.rb, line 87
      def calculate_directory_statistics(directory, pattern = self.class.pattern)
        stats = Rails::CodeStatisticsCalculator.new

        Dir.foreach(directory) do |file_name|
          path = "#{directory}/#{file_name}"

          if File.directory?(path) && !file_name.start_with?(".")
            stats.add(calculate_directory_statistics(path, pattern))
          elsif file_name&.match?(pattern)
            stats.add_by_file_path(path)
          end
        end

        stats
      end