Summary

I would like to achieve the following 2 things for RSpec/FilePath.
I am willing to implement the solution when we reach an agreement on this issue.

Avoid repetitive CustomTransform definitions for single inflection.

When using ActiveSupport::Inflector, we have to write only 1 definition for 1 word with special inflection. On the other hand, when using rubocop-rspec, we have to define multiple definitions (all the composite words derived from a special word). This makes development a little bit less productive.

For example, let's assume that we use a special word like PvP in a project.

When using ActiveSupport::Inflector, all we have to do is write a single rule on PvP.

ActiveSupport::Inflector.inflections(:en) do |inflect|
  inflect.acronym 'PvP'
end

When we use the current CustomTransform, we have to define all the transforms as follows.

RSpec/FilePath:
  CustomTransform:
    PvP: pvp
    SyncPvP: sync_pvp
    AsyncPvP: async_pvp
    PvPOverPvP: pvp_over_pvp
    PvPsController: pvps_controller

This is mainly because the exact-match substitution is handled before snake casing.

https://github.com/rubocop-hq/rubocop-rspec/blob/d69442f17d874cff8f5c11faabd929534c8fc717/lib/rubocop/cop/rspec/file_path.rb#L83-L89

I would like to let the following config just work as ActiveSupport::Inflector config does.

RSpec/FilePath:
  CustomTransform:
    PvP: pvp

Share the same settings as ActiveSupport::Inflector has

I am not so inclined to achieve this as the first one, but, hopefully, I would like to share the same config as we have in Rails application. This motivation is not applicable to non-Rails user. Therefore, I would like to use less-invasive way to achieve this.

In our project, we are using require directive in config YAML to require config/initializers/inflections.rb, where ActiveSupport::Inflector config exists, but there may be a more sophisticated intuitive way.

How to solve this issue

IMHO, I believe that ActiveSupport::Inflector, which is famous for its sophisticated string handling, can solve this issue. Since this idea has both pros and cons, I have set up this issue.

https://api.rubyonrails.org/classes/ActiveSupport/Inflector.html

If RuboCop policy prioritize less dependencies over reinventing the wheel, we can just partially import the code from ActiveSupport::Inflector

Pros and Cons

• Pros
  • Avoiding reinventing the wheel on string inflections.
  • Reduced code complexity on current and future code.
• Cons
  • Breaking backward compatibilities a little.
  • Increased dependencies of RuboCop::RSpec on ActiveSupport::Inflector.

Other Information

I made up a gem rubocop-inflector to solve this issue. However, since the gem touch the internal method of rubocop-rspec, later I have found out it is fragile and not so a recommended way to solve the issue. Although it is very thin and comparatively easy to maintain.

https://github.com/aeroastro/rubocop-inflector