An error occurred while Performance/RegexpMatch cop was inspecting

[pgolm]

After upgrading rubocop the following issue is triggered:

An error occurred while Performance/RegexpMatch cop was inspecting

It raises in the following line:

register_purge_url(Card) { card_path('\d+', match.id) if match }

Rubocop version:

$ rubocop -V
0.48.1 (using Parser 2.4.0.0, running on ruby 2.4.1 x86_64-linux)

Stacktrace with rubocop -d:

An error occurred while Performance/RegexpMatch cop was inspecting /app/models/concerns/varnish_cleaner.rb:268:29.
undefined method `type' for nil:NilClass
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/performance/regexp_match.rb:69:in `match_method?'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/performance/regexp_match.rb:97:in `match_node?'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/performance/regexp_match.rb:140:in `check_condition'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/performance/regexp_match.rb:110:in `on_if'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:43:in `block (2 levels) in on_if'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:106:in `with_cop_error_handling'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:42:in `block in on_if'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:41:in `each'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:41:in `on_if'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/ast/traversal.rb:154:in `on_block'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:47:in `on_block'
(eval):2:in `block in on_begin'
(eval):2:in `each'
(eval):2:in `on_begin'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:47:in `on_begin'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/ast/traversal.rb:141:in `on_while'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:47:in `on_module'                                                                                     [25/1892]
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/ast/traversal.rb:12:in `walk'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/commissioner.rb:60:in `investigate'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/team.rb:124:in `investigate'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/team.rb:112:in `offenses'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cop/team.rb:54:in `inspect_file'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:248:in `inspect_file'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:195:in `block in do_inspection_loop'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:227:in `block in iterate_until_no_changes'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:220:in `loop'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:220:in `iterate_until_no_changes'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:191:in `do_inspection_loop'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:101:in `block in file_offenses'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:111:in `file_offense_cache'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:99:in `file_offenses'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:90:in `process_file'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:68:in `block in each_inspected_file'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:65:in `each'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:65:in `reduce'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:65:in `each_inspected_file'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:57:in `inspect_files'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/runner.rb:36:in `run'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cli.rb:72:in `execute_runner'
/usr/local/bundle/gems/rubocop-0.48.1/lib/rubocop/cli.rb:27:in `run'
/usr/local/bundle/gems/rubocop-0.48.1/bin/rubocop:13:in `block in <top (required)>'
/usr/local/lib/ruby/2.4.0/benchmark.rb:308:in `realtime'
/usr/local/bundle/gems/rubocop-0.48.1/bin/rubocop:12:in `<top (required)>'
/usr/local/bundle/bin/rubocop:17:in `load'
/usr/local/bundle/bin/rubocop:17:in `<main>'

[bbatsov]

I can't reproduce this with RuboCop 0.49.

[pocke]

We need to specify TargetRubyVersion to reproduce this error.

AllCops:
  TargetRubyVersion: 2.4

minimum code to reproduce: a if match