Style/InvertibleUnlessCondition autocorrections may break application logic

[indiebrain]

Given an specific style of comparison expression where the arguments are Modules or Classes Style/InvertibleUnlessCondition's autocorrection can break application logic.

Expected behavior

rubocop --autocorrect --only Style/InvertibleUnlessCondition

Either this cop should not run when running "safe" autocorrections - via the -a or --autocorrect flags - or, the Cop should ignore expressions comparing Module / Class hierarchies.

Actual behavior

Comparisons using a Module's Class's hierarchy break.

Steps to reproduce the problem

$ ruby --version
ruby 3.1.2p20

1. Define a method under test which violates this Cop - example_test.rb

require "minitest/autorun"

class ExampleTest < Minitest::Test
  def test_is_not_ancestor_of_standard_error
    my_mod = Class.new(Object)

    not_an_error_class = true unless my_mod <= StandardError

    assert not_an_error_class
  end

  def test_is_ancestor_of_standard_error
    my_mod = Class.new(StandardError)

    not_an_error_class = true unless my_mod <= StandardError

    refute not_an_error_class
  end
end

2. Run the test and see it pass:

$ ruby example_test.rb
Run options: --seed 58076

# Running:

..

Finished in 0.000446s, 4484.3049 runs/s, 4484.3049 assertions/s.

2 runs, 2 assertions, 0 failures, 0 errors, 0 skips

3. Run the rubocop with the Style/InvertibleUnlessCondition Cop in "safe autocorrect" mode:

$ rubocop --autocorrect --only Style/InvertibleUnlessCondition example_test.rb
warning: parser/current is loading parser/ruby31, which recognizes 3.1.4-compliant syntax, but you are running 3.1.2.
Please see https://github.com/whitequark/parser#compatibility-with-ruby-mri.
Inspecting 1 file
C

Offenses:

example_test.rb:7:5: C: [Corrected] Style/InvertibleUnlessCondition: Favor if with inverted condition over unless.
    not_an_error_class = true unless my_mod <= StandardError
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
example_test.rb:15:5: C: [Corrected] Style/InvertibleUnlessCondition: Favor if with inverted condition over unless.
    not_an_error_class = true unless my_mod <= StandardError
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

1 file inspected, 2 offenses detected, 2 offenses corrected

4. The test will now fail

$ ruby example_test.rb
Run options: --seed 28429

# Running:

F.

Finished in 0.000665s, 3007.5188 runs/s, 3007.5188 assertions/s.

  1) Failure:
ExampleTest#test_is_not_ancestor_of_standard_error [example_test.rb:9]:
Expected nil to be truthy.

2 runs, 2 assertions, 1 failures, 0 errors, 0 skips

RuboCop version

Include the output of rubocop -V or bundle exec rubocop -V if using Bundler.
If you see extension cop versions (e.g. rubocop-performance, rubocop-rspec, and others)
output by rubocop -V, include them as well. Here's an example:

$ rubocop -V
1.50.1 (using Parser 3.2.2.0, rubocop-ast 1.28.0, running on ruby 3.1.2) [arm64-darwin21]
  - rubocop-graphql 1.0.1
  - rubocop-performance 1.16.0
  - rubocop-rails 2.19.0
  - rubocop-rspec 2.17.1
  - rubocop-sorbet 0.7.0