Dr. Rubocop

Or: How I Learned to
Stop Worrying and
Love the Codebase

Transcript

1. DR. RUBOCOP
   Or: How I Learned to
   Stop Worrying and
   Love the Codebase
   

   View Slide

2. DIFFERENT CODEBASES
   100000 lines
   8 years old
   155 contributors
   2000 lines
   1 year old
   6 contributors
   

   View Slide

3. HOW TO GUARANTEE
   UNIFORMITY?
   Or just avoiding some ruby pitfalls
   and repeating the same mistakes
   

   View Slide

4. OVER TIME AND CODEBASES
   How do you keep code style consistent?
   How do you avoid errors and bad code “practices”?
   How do you ensure that your code complexity remains low?
   How do you make sure you are not using inefficient or insecure
   ruby calls?
   How do you make sure your code is using new features or is
   ready for new ruby versions?
   

   View Slide

5. (DR.)
   RUBOCOP
   Rubocop is a Ruby static
   code analyzer. It runs a
   set of cops/checks on
   your codebase.
   

   View Slide

6. RUBOCOP IN LESS THAN 5 MINUTES (1/3)
   In your Gemfile:
   gem 'rubocop', require: false
   Then just install it:
   $ bundle install
   Also integrates with rake and guard.
   

   View Slide

7. Run the auto-config:
   $ bundle exec rubocop —auto-gen-config
   Run `rubocop --config .rubocop_todo.yml`, or add
   `inherit_from: .rubocop_todo.yml` in a .rubocop.yml file.
   Create and tweak your own rubocop.yml:
   require:
   - rubocop-rspec
   inherit_from: .rubocop_todo.yml
   [..]
   RUBOCOP IN LESS THAN 5 MINUTES (2/3)
   

   View Slide

8. Run rubocop with auto-correct enabled:
   $ bundle exec rubocop —auto-correct
   test/vixie/models/job_test.rb:216:5: W: Useless assignment
   to variable - job.
   lib/vixie/tasks/web.rb:22:17: W: Variable Resource used in
   void context.
   52 files inspected, 891 offenses detected, 728 offenses
   corrected
   RUBOCOP IN LESS THAN 5 MINUTES (3/3)
   

   View Slide

9. WORKS WITH
   YOUR TOOLS
   Run it in your ci build,
   or let your favorite
   editor run it for you.
   

   View Slide

10. QUESTIONS?
    

    View Slide

11. Timothée
    Peignier
    Running databases so you don’t
    have to.
    @cyberdelia
    

    View Slide