Fix UtilityFunction false positive with Kernel refinement

[bkuhlmann]

Overview

Seeing the following warning:

lib/versionaire/cast.rb -- 1 warning:
  [7]:UtilityFunction: Versionaire::Cast#Version doesn't depend on instance state (maybe move it to another class?) [https://github.com/troessner/reek/blob/v6.0.2/docs/Utility-Function.md]

...for this refinement:

module Versionaire
  # Refines Kernel in order to provide a top-level Version conversion function.
  module Cast
    refine Kernel do
      def Version object
        Versionaire::Version object
      end
    end
  end
end

Potential Usage:

using Versionaire::Cast

Version "1.2.3"  # => #<struct Versionaire::Version major=1, minor=2, patch=3>

Desired Behavior

It would be nice to not flag this as a violation in this case. This is similar in nature to what was reported earlier.

Notes

I do a lot with refinements so, for context, this might help:

• Refinements - A collection of enhancements to Ruby core classes.
• Versionaire - The Ruby Version type, shown above, that I'd like to access at the Kernel level much like Integer, String, Array, Hash, etc.

[mvz]

This makes sense. I'm going to take a look at how we can support refinements in Reek.

[bkuhlmann]

In case it's of interest/help, here's the Reek configuration I ended up settling on to workaround this issue:

detectors:
  UncommunicativeMethodName:
    exclude:
    - Cast#Version
    - Versionaire#Version
  UtilityFunction:
    exclude:
    - Versionaire::Cast#Version

Due to implementing a Ruby cast/conversion function, this also causes Reek's UncommunicativeMethodName analyzer to trip too.

[mvz]

I've investigated this a bit further and it looks like even if Reek correctly recognizes refinements (and it should!), this would still be considered a UtilityFunction, just like in the following case:

module Foo
  def Version object
    Versionaire::Version object
  end
end

However, with proper support, you should be able to exclude Kernel#Version instead of Cast#Version.

[bkuhlmann]

🙇 @mvz. OK, so reduced to a utility function but not uncommunicative if I understand correctly? Yep, I'll give this a look once the next version is released of Reek. 😉