calculate_directory_statistics

# File railties/lib/rails/code_statistics.rb, line 29
    def calculate_directory_statistics(directory, pattern = /.*\.rb$/)
      stats = { "lines" => 0, "codelines" => 0, "classes" => 0, "methods" => 0 }

      Dir.foreach(directory) do |file_name|
        if File.directory?(directory + "/" + file_name) and (/^\./ !~ file_name)
          newstats = calculate_directory_statistics(directory + "/" + file_name, pattern)
          stats.each { |k, v| stats[k] += newstats[k] }
        end

        next unless file_name =~ pattern

        f = File.open(directory + "/" + file_name)
        comment_started = false
        while line = f.gets
          stats["lines"]     += 1
          if(comment_started)
            if line =~ /^=end/
              comment_started = false
            end
            next
          else
            if line =~ /^=begin/
              comment_started = true
              next
            end
          end
          stats["classes"]   += 1 if line =~ /^\s*class\s+[_A-Z]/
          stats["methods"]   += 1 if line =~ /^\s*def\s+[_a-z]/
          stats["codelines"] += 1 unless line =~ /^\s*$/ || line =~ /^\s*#/
        end
      end

      stats
    end