Error invoking Style/NilComparison

[dduugg]

---

Expected behavior

No rubocop error when invoking Style/NilComparison

Actual behavior

rubocop error when invoking Style/NilComparison

Steps to reproduce the problem

Create a.rb with:

class A
  def foo
    bar if baz == nil
  end
end

Then:

$ rubocop -d --only Style/NilComparison a.rb
For /path/to/project: configuration from /path/to/project/.rubocop.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-performance-1.9.2/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-performance-1.9.2/config/default.yml
Default configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-rake-0.5.1/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-rake-0.5.1/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-rspec-2.1.0/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-rspec-2.1.0/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-sorbet-0.5.1/config/default.yml
configuration from /path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-sorbet-0.5.1/config/default.yml
Inspecting 1 file
Scanning /path/to/project/a.rb
An error occurred while Style/NilComparison cop was inspecting /path/to/project/a.rb:3:11.
undefined method `method?' for #<RuboCop::AST::IfNode:0x00007ff1a8babed0>
Did you mean?  method
               methods
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/style/nil_comparison.rb:53:in `block (2 levels) in on_send'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/base.rb:339:in `correct'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/base.rb:126:in `add_offense'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/style/nil_comparison.rb:45:in `block in on_send'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/style/nil_comparison.rb:48:in `nil_comparison?'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/style/nil_comparison.rb:68:in `style_check?'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/style/nil_comparison.rb:44:in `on_send'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:136:in `public_send'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:136:in `block (2 levels) in trigger_restricted_cops'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:166:in `with_cop_error_handling'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:135:in `block in trigger_restricted_cops'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:134:in `each'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:134:in `trigger_restricted_cops'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:70:in `on_send'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-ast-1.4.1/lib/rubocop/ast/traversal.rb:153:in `on_if'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:71:in `on_if'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-ast-1.4.1/lib/rubocop/ast/traversal.rb:154:in `on_def'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:71:in `on_def'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-ast-1.4.1/lib/rubocop/ast/traversal.rb:154:in `on_class'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:71:in `on_class'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-ast-1.4.1/lib/rubocop/ast/traversal.rb:20:in `walk'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/commissioner.rb:86:in `investigate'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/team.rb:157:in `investigate_partial'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cop/team.rb:83:in `investigate'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:315:in `inspect_file'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:259:in `block in do_inspection_loop'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:293:in `block in iterate_until_no_changes'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:286:in `loop'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:286:in `iterate_until_no_changes'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:255:in `do_inspection_loop'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:132:in `block in file_offenses'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:157:in `file_offense_cache'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:131:in `file_offenses'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:122:in `process_file'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:101:in `block in each_inspected_file'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:100:in `each'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:100:in `reduce'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:100:in `each_inspected_file'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:86:in `inspect_files'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/runner.rb:47:in `run'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/command/execute_runner.rb:26:in `block in execute_runner'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/command/execute_runner.rb:52:in `with_redirect'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/command/execute_runner.rb:25:in `execute_runner'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/command/execute_runner.rb:17:in `run'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/command.rb:11:in `run'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli/environment.rb:18:in `run'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli.rb:65:in `run_command'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli.rb:72:in `execute_runners'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/lib/rubocop/cli.rb:41:in `run'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/exe/rubocop:13:in `block in <top (required)>'
/path/to/.rbenv/versions/2.6.6/lib/ruby/2.6.0/benchmark.rb:308:in `realtime'
/path/to/project/vendor/bundle/ruby/2.6.0/gems/rubocop-1.9.0/exe/rubocop:12:in `<top (required)>'
/path/to/project/vendor/bundle/ruby/2.6.0/bin/rubocop:23:in `load'
/path/to/project/vendor/bundle/ruby/2.6.0/bin/rubocop:23:in `<top (required)>'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli/exec.rb:63:in `load'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli/exec.rb:63:in `kernel_load'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli/exec.rb:28:in `run'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli.rb:494:in `exec'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/vendor/thor/lib/thor/invocation.rb:127:in `invoke_command'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/vendor/thor/lib/thor.rb:392:in `dispatch'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli.rb:30:in `dispatch'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/vendor/thor/lib/thor/base.rb:485:in `start'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/cli.rb:24:in `start'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/exe/bundle:49:in `block in <top (required)>'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/lib/bundler/friendly_errors.rb:130:in `with_friendly_errors'
/path/to/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/bundler-2.2.6/exe/bundle:37:in `<top (required)>'
/path/to/.rbenv/versions/2.6.6/bin/bundle:23:in `load'
/path/to/.rbenv/versions/2.6.6/bin/bundle:23:in `<main>'
.

1 file inspected, no offenses detected

1 error occurred:
An error occurred while Style/NilComparison cop was inspecting /path/to/project/a.rb:3:11.
Errors are usually caused by RuboCop bugs.
Please, report your problems to RuboCop's issue tracker.
https://github.com/rubocop-hq/rubocop/issues

Mention the following information in the issue report:
1.9.0 (using Parser 3.0.0.0, rubocop-ast 1.4.1, running on ruby 2.6.6 x86_64-darwin19)
Finished in 0.5082079999847338 seconds

RuboCop version

$ rubocop -V
1.9.0 (using Parser 3.0.0.0, rubocop-ast 1.4.1, running on ruby 2.6.6 x86_64-darwin19)
  - rubocop-performance 1.9.2
  - rubocop-rake 0.5.1
  - rubocop-rspec 2.1.0
  - rubocop-sorbet 0.5.1