Reek — code smell detection for Ruby

Reek is a tool that examines Ruby classes, modules and methods and reports any code smells it finds. Install it like this:

  $ gem install reek

and run it like this:

  $ reek [options] [dir_or_source_file]*

For a full list of command-line options see the Reek wiki or run

  $ reek --help

Example

Imagine a source file csv_writer.rb containing:

  class CsvWriter
    def write_line(fields)
      if (fields.length == 0)
        puts
      else
        write_field(fields[0])
        1.upto(fields.length-1) do |i|
          print ","
          write_field(fields[i])
        end
        puts
      end
    end

    #...
  end

Reek will report the following code smells in this file:

  $ reek csv_writer.rb
  CsvWriter#write_line calls fields.length multiple times (Duplication)
  CsvWriter#write_line has approx 6 statements (Long Method)
  CsvWriter#write_line/block has the variable name 'i' (Uncommunicative Name)

Features

Reek currently includes checks for some aspects of the following smells:

• Control Couple
• Data Clump
• Feature Envy
• Large Class
• Long Method
• Long Parameter List
• Simulated Polymorphism
• Uncommunicative Name

…and more. See the Reek wiki for up to date details of exactly what Reek will check in your code.

Tool Integration

Reek integrates with many of your favourite tools:

• Use Reek::RakeTask to easily add Reek to your Rakefile
• Use Reek::Spec to add the should_not reek custom matcher to your Rspec examples
• Reek is fully compliant with Ruby 1.8.6, 1.8.7 and 1.9.1

Dependencies

Reek makes use of the following other gems:

• ruby_parser
• sexp_processor
• ruby2ruby

Learn More

Find out more about Reek from any of the following sources:

• Browse the Reek documentation at wiki.github.com/kevinrutherford/reek
• Browse the code or install the latest cutting-edge beta version from github.com/kevinrutherford/reek/tree
• Read the code API at rdoc.info/projects/kevinrutherford/reek