Stats of rails project over time

run_this_in_shell.sh

ruby -e 'require "date"; f=File.open("results.txt", "w"); (2013..2019).to_a.reverse.map{|y| (1..12).to_a.reverse.each{|m| d = Date.new(y, m, 1); next if d < Date.new(2013, 4, 3) || d > Date.new(2019, 2, 1); d = d.strftime("%Y-%m-%d"); commit = `git log --before=#{d} -n 1 --format=format:"%H"`.chomp; f.puts "#{d}: #{commit}"; f.puts `git checkout #{commit} && ruby stats.rb` }}'

stats.rb

require "active_support/core_ext/enumerable"
require "active_support/core_ext/string/inflections"

class CodeStatisticsCalculator #:nodoc:
  attr_reader :lines, :code_lines, :classes, :methods

  PATTERNS = {
    rb: {
      line_comment: /^\s*#/,
      begin_block_comment: /^=begin/,
      end_block_comment: /^=end/,
      class: /^\s*class\s+[_A-Z]/,
      method: /^\s*def\s+[_a-z]/,
    },
    js: {
      line_comment: %r{^\s*//},
      begin_block_comment: %r{^\s*/\*},
      end_block_comment: %r{\*/},
      method: /function(\s+[_a-zA-Z][\da-zA-Z]*)?\s*\(/,
    },
    coffee: {
      line_comment: /^\s*#/,
      begin_block_comment: /^\s*###/,
      end_block_comment: /^\s*###/,
      class: /^\s*class\s+[_A-Z]/,
      method: /[-=]>/,
    }
  }

  PATTERNS[:minitest] = PATTERNS[:rb].merge method: /^\s*(def|test)\s+['"_a-z]/
  PATTERNS[:rake] = PATTERNS[:rb]

  def initialize(lines = 0, code_lines = 0, classes = 0, methods = 0)
    @lines = lines
    @code_lines = code_lines
    @classes = classes
    @methods = methods
  end

  def add(code_statistics_calculator)
    @lines += code_statistics_calculator.lines
    @code_lines += code_statistics_calculator.code_lines
    @classes += code_statistics_calculator.classes
    @methods += code_statistics_calculator.methods
  end

  def add_by_file_path(file_path)
    File.open(file_path) do |f|
      add_by_io(f, file_type(file_path))
    end
  end

  def add_by_io(io, file_type)
    patterns = PATTERNS[file_type] || {}

    comment_started = false

    while line = io.gets
      @lines += 1

      if comment_started
        if patterns[:end_block_comment] && line =~ patterns[:end_block_comment]
          comment_started = false
        end
        next
      else
        if patterns[:begin_block_comment] && line =~ patterns[:begin_block_comment]
          comment_started = true
          next
        end
      end

      @classes   += 1 if patterns[:class] && line =~ patterns[:class]
      @methods   += 1 if patterns[:method] && line =~ patterns[:method]
      if line !~ /^\s*$/ && (patterns[:line_comment].nil? || line !~ patterns[:line_comment])
        @code_lines += 1
      end
    end
  end

  private
    def file_type(file_path)
      if file_path.end_with? "_test.rb"
        :minitest
      else
        File.extname(file_path).sub(/\A\./, "").downcase.to_sym
      end
    end
end

class CodeStatistics #:nodoc:
  TEST_TYPES = ["Controller tests",
                "Helper tests",
                "Model tests",
                "Mailer tests",
                "Job tests",
                "Integration tests",
                "System tests"]

  HEADERS = { lines: " Lines", code_lines: "   LOC", classes: "Classes", methods: "Methods" }

  def initialize(*pairs)
    @pairs      = pairs
    @statistics = calculate_statistics
    @total      = calculate_total if pairs.length > 1
  end

  def to_s
    print_header
    @pairs.each { |pair| print_line(pair.first, @statistics[pair.first]) }
    print_splitter

    if @total
      print_line("Total", @total)
      print_splitter
    end

    print_code_test_stats
  end

  private
    def calculate_statistics
      Hash[@pairs.map { |pair| [pair.first, calculate_directory_statistics(pair.last)] }]
    end

    def calculate_directory_statistics(directory, pattern = /^(?!\.).*?\.(rb|js|coffee|rake)$/)
      stats = CodeStatisticsCalculator.new

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

        if File.directory?(path) && (/^\./ !~ file_name)
          stats.add(calculate_directory_statistics(path, pattern))
        elsif file_name =~ pattern
          stats.add_by_file_path(path)
        end
      end

      stats
    end

    def calculate_total
      @statistics.each_with_object(CodeStatisticsCalculator.new) do |pair, total|
        total.add(pair.last)
      end
    end

    def calculate_code
      code_loc = 0
      @statistics.each { |k, v| code_loc += v.code_lines unless TEST_TYPES.include? k }
      code_loc
    end

    def calculate_tests
      test_loc = 0
      @statistics.each { |k, v| test_loc += v.code_lines if TEST_TYPES.include? k }
      test_loc
    end

    def width_for(label)
      [@statistics.values.sum { |s| s.send(label) }.to_s.size, HEADERS[label].length].max
    end

    def print_header
      print_splitter
      print "| Name                "
      HEADERS.each do |k, v|
        print " | #{v.rjust(width_for(k))}"
      end
      puts " | M/C | LOC/M |"
      print_splitter
    end

    def print_splitter
      print "+----------------------"
      HEADERS.each_key do |k|
        print "+#{'-' * (width_for(k) + 2)}"
      end
      puts "+-----+-------+"
    end

    def print_line(name, statistics)
      m_over_c   = (statistics.methods / statistics.classes) rescue m_over_c = 0
      loc_over_m = (statistics.code_lines / statistics.methods) - 2 rescue loc_over_m = 0

      print "| #{name.ljust(20)} "
      HEADERS.each_key do |k|
        print "| #{statistics.send(k).to_s.rjust(width_for(k))} "
      end
      puts "| #{m_over_c.to_s.rjust(3)} | #{loc_over_m.to_s.rjust(5)} |"
    end

    def print_code_test_stats
      code  = calculate_code
      tests = calculate_tests

      puts "  Code LOC: #{code}     Test LOC: #{tests}     Code to Test Ratio: 1:#{sprintf("%.1f", tests.to_f / code)}"
      puts ""
    end
end




STATS_DIRECTORIES = [
  %w(Controllers        app/controllers),
  %w(Helpers            app/helpers),
  %w(Jobs               app/jobs),
  %w(Models             app/models),
  %w(Mailers            app/mailers),
  %w(Channels           app/channels),
  %w(JavaScripts        app/assets/javascripts),
  %w(Libraries          lib/),
  %w(APIs               app/apis),
  %w(Controller\ tests  test/controllers),
  %w(Helper\ tests      test/helpers),
  %w(Model\ tests       test/models),
  %w(Mailer\ tests      test/mailers),
  %w(Job\ tests         test/jobs),
  %w(Integration\ tests test/integration),
  %w(System\ tests      test/system),
].collect do |name, dir|
  [ name, "./#{dir}" ]
end.select { |name, dir| File.directory?(dir) }

spec_types = begin
                dirs = Dir['./spec/**/*_spec.rb'].
                  map { |f| f.sub(/^\.\/(spec\/\w+)\/.*/, '\\1') }.
                  uniq.
                  select { |f| File.directory?(f) }
                Hash[dirs.map { |d| [d.split('/').last, d] }]
              end

spec_types.each do |type, dir|
  name = type.singularize.capitalize

  ::STATS_DIRECTORIES << ["#{name} specs", dir]
  ::CodeStatistics::TEST_TYPES << "#{name} specs"
end

CodeStatistics.new(*STATS_DIRECTORIES).to_s