1 files changed, 115 insertions, 0 deletions
diff --git a/railties/lib/rails/code_statistics.rb b/railties/lib/rails/code_statistics.rb
new file mode 100644
index 0000000000..9c447c366f
--- /dev/null
+++ b/railties/lib/rails/code_statistics.rb
@@ -0,0 +1,115 @@
+# frozen_string_literal: true
+
+require "rails/code_statistics_calculator"
+require "active_support/core_ext/enumerable"
+
+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