Infinite loop with Style/IfUnlessModifier

[JoeCohen]

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---

Note: This may be the same bug as #8006

Expected behavior

Either autocorrect or ignore this bit of code:

      merge = if ver.respond_to?(:merge_source_id)
                get_version_merge_link(obj, ver)
              end

Actual behavior

$ rubocop -f html -o rubocop.html --only Style/IfUnlessModifier -a
Infinite loop detected in /vagrant/mushroom-observer/app/helpers/version_helper.rb.
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:292:in check_for_infinite_loop' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:275:in block in iterate_until_no_changes'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:274:in loop' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:274:in iterate_until_no_changes'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:245:in do_inspection_loop' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:124:in block in file_offenses'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:148:in file_offense_cache' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:122:in file_offenses'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:113:in process_file' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:92:in block in each_inspected_file'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in each' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in reduce'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in each_inspected_file' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:78:in inspect_files'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:39:in run' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command/execute_runner.rb:21:in execute_runner'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command/execute_runner.rb:13:in run' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command.rb:10:in run'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/environment.rb:17:in run' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:65:in run_command'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:72:in execute_runners' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:41:in run'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/exe/rubocop:13:in block in <top (required)>' /home/vagrant/.rvm/rubies/ruby-2.6.6/lib/ruby/2.6.0/benchmark.rb:308:in realtime'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/exe/rubocop:12:in <top (required)>' /home/vagrant/.rvm/gems/ruby-2.6.6/bin/rubocop:23:in load'
/home/vagrant/.rvm/gems/ruby-2.6.6/bin/rubocop:23:in <main>' /home/vagrant/.rvm/gems/ruby-2.6.6/bin/ruby_executable_hooks:24:in eval'
/home/vagrant/.rvm/gems/ruby-2.6.6/bin/ruby_executable_hooks:24:in <main>' VM:/vagrant/mushroom-observer $ rubocop -f html -o rubocop.html --only Style/IfUnlessModifier -a app/helpers/version_helper.rb Infinite loop detected in /vagrant/mushroom-observer/app/helpers/version_helper.rb. /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:292:in check_for_infinite_loop'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:275:in block in iterate_until_no_changes' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:274:in loop'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:274:in iterate_until_no_changes' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:245:in do_inspection_loop'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:124:in block in file_offenses' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:148:in file_offense_cache'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:122:in file_offenses' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:113:in process_file'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:92:in block in each_inspected_file' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in each'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in reduce' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:91:in each_inspected_file'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:78:in inspect_files' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/runner.rb:39:in run'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command/execute_runner.rb:21:in execute_runner' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command/execute_runner.rb:13:in run'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/command.rb:10:in run' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli/environment.rb:17:in run'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:65:in run_command' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:72:in execute_runners'
/home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/lib/rubocop/cli.rb:41:in run' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/exe/rubocop:13:in block in <top (required)>'
/home/vagrant/.rvm/rubies/ruby-2.6.6/lib/ruby/2.6.0/benchmark.rb:308:in realtime' /home/vagrant/.rvm/gems/ruby-2.6.6/gems/rubocop-0.83.0/exe/rubocop:12:in <top (required)>'
/home/vagrant/.rvm/gems/ruby-2.6.6/bin/rubocop:23:in load' /home/vagrant/.rvm/gems/ruby-2.6.6/bin/rubocop:23:in

'
/home/vagrant/.rvm/gems/ruby-2.6.6/bin/ruby_executable_hooks:24:in eval' /home/vagrant/.rvm/gems/ruby-2.6.6/bin/ruby_executable_hooks:24:in '

Steps to reproduce the problem

The problem can be reproduced by running

$ rubocop -f html -o rubocop.html --only Style/IfUnlessModifier -a

on a file containing

      merge = if ver.respond_to?(:merge_source_id)
                get_version_merge_link(obj, ver)
              end

RuboCop version

Include the output of rubocop -V or bundle exec rubocop -V if using Bundler. Here's an example:

$ rubocop -V
0.83.0 (using Parser 2.7.1.2, running on ruby 2.6.6 x86_64-linux)