Why doesn't Rubymine recognize my namespaced inherited controller?

Question

I have a namespace called backend and the following controller application_controller.rb:

class Backend::ApplicationController < ApplicationController
end

Now I inherit this controller from my user controller:

class Backend::UserController < Backend::ApplicationController
  def index
    @users = User.all
  end

  ...
end

For the inheritance of the application controller Rubymine shows me the following error:

This code is fine for the ruby interpreter. How can I teach this to Rubymine?

I'm on RubyMine 2018.2.3 and using Ruby 2.5.1p57.

Thank you in advance!

Answer 1

I'm guessing that you should try the proper "longhand" way of actually opening the module.

These two approaches are not actually equivalent:

class Backend::ApplicationController < ApplicationController
end

module Backend
  class ApplicationController < ::ApplicationController
  end
end

As the later actually properly sets the module nesting to work as expected:

module Backend
  # this class will inherit from Backend::ApplicationController
  # and not ::ApplicationController
  class UserController < ApplicationController
  end
end

In general the "short-cut" definition (class Foo::Bar) of "namespaced" classes should be avoided as it invites problems with constant lookup.