Inconsistent reporting for FeatureEnvy when using module_function and/or private_class_method

[pardaloupa]

The following code

module Admins
  class << self
    private
      attr_reader: users
  end

  module_function
  ...
  
  def show_active_users
   ...
   active = active_users
   ...
  end
    
  def users
    @users ||=[]
  end
  
  def active_users
    active =
      users
        .select { |user| user.deleted? == false }
    active.map { |user| user.visible = true
   
    Workspace.fetch_users(active) unless active.empty?
  end
  private_class_method :active_users
end

refers to 'user' more than self (maybe move it to another class?)

Goes away if I use def self.active_users. (prepend self)

The same exact issue occurs when using module_function.

Reek seems to fail to detect that methods defined using module_function/ private_class_method are class instance methods and not instance methods

This is the same issue as #1337 this merge request is also related #1338

[mvz]

I just started looking into this and the problem is that with module_function both a class method and an instance method are created. So, you can still include the Module and will have active_users as a (private) instance method. Hence, it is a valid candidate to check for FeatureEnvy (and UtilityFunction).

[mvz]

@troessner wdyt?

[troessner]

Hmmm, to me it seems like this is one of the edge cases where we'll never have a solution that works for everybody. I agree with @mvz that the check is valid. @mvz what do you think about updating our docs for FeatureEnvy with a proper example and reasoning behind our decision?

[mvz]

I've just realised that the situation is even more confusing for modules in general: If you define a module for the purpose using it with Class#extend, Reek will treat the methods as instance methods, even though they will be class methods on the extended class.