[DRE-maint] Bug#888185: rubocop: FTBFS on ruby2.5: Error: FileUtils.rmdir(attack_target_dir)

[Chris West (Faux)]

Source: rubocop
Version: 0.51.0+dfsg-1
Severity: important
User: debian-ruby at lists.debian.org
Usertags: ruby2.5

Dear Maintainer,

This package fails to build against ruby2.5. Soon, there will
be a transition to ruby2.5, and this package will FTBFS in sid.

There may be some details on the wiki about common problems:
https://wiki.debian.org/Teams/Ruby/Ruby25Transition

Build log excerpt:


Failures:

  1) RuboCop::ResultCache cached result that was saved with no command line option when no option is given when a symlink is present in the cache location and symlink attack protection is disabled permits caching and prints no warning
     Failure/Error: FileUtils.rmdir(attack_target_dir)

     Errno::ENOTEMPTY:
       Directory not empty @ dir_s_rmdir - /tmp/d20180123-1310-1kp5vxe
     # /build/rubocop-0.51.0+dfsg/spec/rubocop/result_cache_spec.rb:95:in `block (5 levels) in <top (required)>'
     # /build/rubocop-0.51.0+dfsg/lib/rubocop/rspec/shared_contexts.rb:27:in `block (4 levels) in <top (required)>'
     # /build/rubocop-0.51.0+dfsg/lib/rubocop/rspec/shared_contexts.rb:26:in `chdir'
     # /build/rubocop-0.51.0+dfsg/lib/rubocop/rspec/shared_contexts.rb:26:in `block (3 levels) in <top (required)>'
     # /build/rubocop-0.51.0+dfsg/lib/rubocop/rspec/shared_contexts.rb:8:in `block (2 levels) in <top (required)>'

Finished in 33.85 seconds (files took 3.52 seconds to load)
17503 examples, 1 failure, 1 pending

Failed examples:

rspec /build/rubocop-0.51.0+dfsg/spec/rubocop/result_cache_spec.rb:121 # RuboCop::ResultCache cached result that was saved with no command line option when no option is given when a symlink is present in the cache location and symlink attack protection is disabled permits caching and prints no warning

Randomized with seed 48248

/usr/bin/ruby2.5 /usr/bin/rspec --pattern ./spec/\*\*/\*_spec.rb failed
ERROR: Test "ruby2.5" failed. Exiting.
dh_auto_install: dh_ruby --install /build/rubocop-0.51.0\+dfsg/debian/rubocop returned exit code 1
debian/rules:6: recipe for target 'binary' failed
make: *** [binary] Error 1
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2

Full build log:
https://rbuild.fau.xxx/2018-01-23/rubocop.log

Please fix it!

Cheers,
Chris.