This gem holds makandra's default Rubocop configuration. It is currently very relaxed, and will evolve over time.

Note that we lock each version on a specific Rubocop version, as Rubocop's syntax changes regularly.

Installation

Add this line to your application's Gemfile:

gem 'makandra-rubocop'

And then execute:

$ bundle

Or install it yourself as:

$ gem install makandra-rubocop

Usage

Add a .rubocop.yml to your project with the following contents:

For Ruby

inherit_gem:
  makandra-rubocop: config/default.yml

For Rails

inherit_gem:
  makandra-rubocop:
    - config/default.yml
    - config/ext/rails.yml

For RSpec

inherit_gem:
  makandra-rubocop:
    - config/default.yml
    - config/ext/rspec.yml

Any per-project rules can then be defined in the .rubocop.yml:

inherit_gem:
  makandra-rubocop:
    - config/default.yml
    - config/ext/rails.yml

AllCops:
  Exclude:
    - 'lib/assets/**/*'

Layout/MultilineArrayLineBreaks:
  Enabled: true

It also might be desired to set inherit_mode, which specifies which configuration keys that have array values should be merged together instead of overriding the inherited value:

inherit_mode:
  merge:
    - Exclude

Executing Rubocop on demand

Run Rubocop via bundle exec rubocop from your project directory.

For an initial run it might also useful to use the auto-correct option (bundle exec rubocop --auto-correct) and carefully check in all changes. You can follow this guide for bigger projects.

Integrating Rubocop into your test suite

We recommend you add an RSpec test that runs rubocop automatically and confirms that there are no offenses. This gem provides one. Simply add spec/rubocop_spec.rb to your project with the following code.

require 'makandra_rubocop/support/rubocop_spec'

Configuring exceptions

Some of our defaults might not fit your project. You can disable specific cops or add exclusions to .rubocop.yml in such cases. You basically have two options:

• Disable cops for specific lines using Ruby comments in your code, like so:

for x in (0..19) # rubocop:disable Style/For

• Disable entire files by adding exclusions to .rubocop.yml, like so:

Style/For:
  Exclude:
    - app/models/example.rb

See Rubocop's configuration manual for more information.

Note that disabling cops should be an exception for extremely rare cases where your code can not be aligned with Rubocop's requirements. If our defaults don't match your opinion, you should discuss with the team.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/makandra/makandra-rubocop.

If you make any changes to this gem's Ruby code, make sure to run rubocop.

Development

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install.

When you're making changes, update the version number in version.rb:

• Increase the major version when you're upgrading a Rubocop dependency (see below)
• Increase the minor version e.g. when disabling a cop

For release run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Upgrading Rubocop dependencies

The following procedure works for either rubocop, rubocop-rails or rubocopo-rspec. (Replace rubocop with the respective dependency name.)

1. Change the rubocop dependency in the Gemspec to the version you want to upgrade to.
2. bundle update rubocop

Next, we need to update our config file to match their updated config. If you have not added the Rubocop remote yet (check with git remote -v), do a git remote add rubocop https://github.com/rubocop-hq/rubocop.git. Then:

1. Update the local copy of the Rubocop repository: git fetch rubocop --no-tags (we can't import their tags or they would clash with ours)
2. Find the commit SHA of the previous and of the new Rubocop version in our Gemspec. The easiest way is to look them up on their releases page.
3. Diff their config/default.yml between the previously used and the new Rubocop version, and write it to a file: git diff $OLDER_SHA $NEWER_SHA config/default.yml > config_diff
4. If you are updating rubocop-rails or rubocop-rspec, edit the config_diff file now and replace config/default.yml with config/ext/{rails,rspec}.yml (respectively).
5. Apply the diff with git apply ./config_diff --3way
6. Resolve merge conflicts carefully and review all changes. We do not want to loose changes in our config files.
7. Delete the patch file
8. Increase the major version (see above)
9. Update the CHANGELOG
10. Commit

License

The gem is available as open source under the terms of the MIT License.