Rails/SaveBang: incorrectly thinks the return value of save is discarded

[akimd]

Hi again!

Expected behavior

In the following sample, the return value of save is checked. Or, more exactly, it is not discarded. So there should be no warnings about it.

$ cat save.rb
res = true
res &&= foo.save
res &&= bar.save
res

Actual behavior

$ bundle exec rubocop save.rb
Inspecting 1 file
C

Offenses:

save.rb:1:1: C: [Correctable] Style/FrozenStringLiteralComment: Missing frozen string literal comment.
res = true
^
save.rb:2:13: C: [Correctable] Rails/SaveBang: Use save! instead of save if the return value is not checked.
res &&= foo.save
            ^^^^
save.rb:3:13: C: [Correctable] Rails/SaveBang: Use save! instead of save if the return value is not checked.
res &&= bar.save
            ^^^^

1 file inspected, 3 offenses detected, 3 offenses autocorrectable

Steps to reproduce the problem

See above.

RuboCop version

$ bundle exec rubocop -V
1.56.3 (using Parser 3.2.2.3, rubocop-ast 1.29.0, running on ruby 3.2.2) [arm64-darwin22]
  - rubocop-rails 2.21.2