Make RuboCop Capybara work as a RuboCop plugin

[bquorning]

This pull request adds support for RuboCop's plugin feature, added in rubocop/rubocop#13792, released in v1.72.

It replaces the ad-hoc inject_defaults! with RuboCop plugins.

Some Rake tasks may still need to use inject_defaults!.

---

Before submitting the PR make sure the following are checked:

• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Updated documentation.
• Added an entry to the CHANGELOG.md if the new code introduces user-observable changes.
• The build (bundle exec rake) passes (be sure to run this locally, since it may produce updated documentation that you will need to commit).

[bquorning]

@koic I tried replicating your pull requests rubocop/rubocop-performance#490 and rubocop/rubocop-rspec#2042, but both locally and on CI I find that bundle exec rake internal_investigation is failing, while bundle exec rubocop will pass. I was hoping you could help me find out what is going wrong?

The error suggests that the rubocop-capybara cops is being run, even though they are not listed under require or plugins in .rubocop.yml.

I have a similar branch with similar changes in rubocop-factory_bot, and the same thing happens – exceptions from one of the FactoryBot cops, even though those cops should not be loaded. And it’s only a problem when running rake internal_investigation.

[bquorning]

I don’t understand why this is necessary, and hope to remove it before merging the PR.

[koic]

Wouldn't using the plugin_name: 'rubocop-capybara' option in the CopsDocumentationGenerator, as in rubocop/rubocop-rspec#2057, resolve the issue?
This eliminates the need to use RuboCop::ConfigLoader.inject_defaults!, as I understand it.

[bquorning]

Using plugin_name made tasks/cops_documentation.rake cleaner, but I still need to patch Rakefile (the 2nd commit) to make bundle exec rake internal_investigation work. Could you have another look please, @koic?

[koic]

@bquorning

As a short answer, the following addition to .rubocop.yml is required.

diff --git a/.rubocop.yml b/.rubocop.yml
index 6507792..af0958b 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,6 +1,7 @@
 inherit_from: .rubocop_todo.yml

 plugins:
+  - rubocop-capybara
   - rubocop-performance
   - rubocop-rake
   - rubocop-rspec
diff --git a/Rakefile b/Rakefile
index 22cbb49..7455206 100644
--- a/Rakefile
+++ b/Rakefile
@@ -23,9 +23,7 @@ RSpec::Core::RakeTask.new(:spec) do |spec|
 end

 desc 'Run RuboCop over this gem'
-RuboCop::RakeTask.new(:internal_investigation) do
-  RuboCop::ConfigLoader.inject_defaults!("#{__dir__}/config/default.yml")
-end
+RuboCop::RakeTask.new(:internal_investigation)

 desc 'Build config/default.yml'
 task :build_config do

Technical Note: This is due to the change from require to plugins.

With the previous the Inject hack, since require was used, loading the config/default.yml configuration was triggered by rubocop-capybara.

Now that it has become a plugin, config/default.yml is loaded based on the plugins specified in .rubocop.yml, with RuboCop as the starting trigger point.

Therefore, to load the configuration, .rubocop.yml must include plugins: rubocop-capybara. Since rubocop-capybara itself doesn't depend on Capybara, this may be considered redundant. However, from the user's perspective, it can also be seen as a necessary configuration example.

Additionally, rubocop-factory_bot rubocop/rubocop-factory_bot#139 is likely to be resolved in the same way. This issue specifically affects cops that provide options like EnforcedStyle in config/default.yml. In other words, cops that don't have configuration options in their configuration files will not encounter this error.

[bquorning]

Thank you @koic, that solved my problems.

[bquorning]

cc @ydah

[ydah]

Thank you