When you are into developing Ruby code, or even Ruby near stuff like Puppet modules, or Chef cookbooks, there is a nice tool you should have a look at.
The RuboCop can help you writing better Ruby code, it certainly did it for me.
In short words, RubyCop is a code analyzer that checks Ruby code against common style guidelines and tries to detect a lot of mistakes and errors that you might write into your code.
There are a lot of configuration options, and even an auto-correct functionality, that updates your code.
Either install the gem, or add it to your Gemfile:
gem 'rubocop', require: false
You can just run it without configuration, and it will look for all Ruby files in your work directory.
$ rubocop Inspecting 19 files ....C............CC Offenses: lib/test/cli.rb:3:3: C: Missing top-level class documentation comment. class CLI ^^^^^ lib/test/cli.rb:36:1: C: Extra empty line detected at method body beginning. lib/test/cli.rb:41:1: C: Extra empty line detected at block body beginning. lib/test/cli.rb:45:4: C: Final newline missing. end bin/test:12:1: C: Missing space after #. #api.login('username', 'Passw0rd') unless api.logged_in? ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ bin/test:15:3: C: Missing space after #. #puts response.code ^^^^^^^^^^^^^^^^^^^ bin/test:19:1: C: Missing space after #. #session.save(file) ^^^^^^^^^^^^^^^^^^^ 18 files inspected, 7 offenses detected
You can add it as a rake job to your Rakefile:
require 'rubocop/rake_task' RuboCop::RakeTask.new task default: [:spec, :rubocop]
And run the test via your rake tests:
$ rake $ rake rubocop
There are a lot of options to modify the behavior and expectations of RuboCop.
Here is a short example I used with recent Puppet module.
require: rubocop-rspec AllCops: TargetRubyVersion: 1.9 Include: - ./**/*.rb Exclude: - vendor/**/* - .vendor/**/* - pkg/**/* - spec/fixtures/**/* # We don't use rspec in this way RSpec/DescribeClass: Enabled: False RSpec/ImplicitExpect: Enabled: False # Example length is not necessarily an indicator of code quality RSpec/ExampleLength: Enabled: False RSpec/NamedSubject: Enabled: False
Where to go next
- Check the documentation for all the cops (e.g. Linting)
- Check available command line arguments
- Search what other people are doing with Rubocop on GitHub