Exception thrown by Rails/Presence if local method blank? is defined

[dominicsayers]

If a class has a method blank? and that method is called with if blank? then the cop Rails/Presence throws an exception

An error occurred while Rails/Presence cop was inspecting /Users/dominic/tmp/a.rb:5:4.
undefined method `source' for nil:NilClass

---

Expected behavior

I expect the Rails/Presence cop not to throw an exception when parsing syntactically correct code

Actual behavior

The Rails/Presence cop throws an exception when parsing a reference to a locally defined blank? method

Steps to reproduce the problem

1. Define a class as follows (tmp/a.rb)

class A
  def blank?; end

  def foo
    puts "bar" if blank?
  end
end

2. rubocop --debug tmp/a.rb

For /Users/dominic: configuration from /Users/dominic/.rubocop.yml
Default configuration from /Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/config/default.yml
Inheriting configuration from /Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/config/enabled.yml
Inheriting configuration from /Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/config/disabled.yml
Inspecting 1 file
Scanning /Users/dominic/tmp/a.rb
An error occurred while Rails/Presence cop was inspecting /Users/dominic/tmp/a.rb:5:4.
undefined method `source' for nil:NilClass
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/rails/presence.rb:113:in `replacement'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/rails/presence.rb:107:in `message'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/rails/presence.rb:76:in `block in on_if'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/rails/presence.rb:45:in `redundant_receiver_and_other'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/rails/presence.rb:74:in `on_if'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:44:in `block (2 levels) in on_if'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:109:in `with_cop_error_handling'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:43:in `block in on_if'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:42:in `each'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:42:in `on_if'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:95:in `on_def'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:48:in `on_def'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:49:in `block in on_begin'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:49:in `each'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:49:in `on_begin'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:48:in `on_begin'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:88:in `on_class'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:48:in `on_class'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/ast/traversal.rb:12:in `walk'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/commissioner.rb:60:in `investigate'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/team.rb:114:in `investigate'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/team.rb:102:in `offenses'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cop/team.rb:44:in `inspect_file'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:258:in `inspect_file'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:205:in `block in do_inspection_loop'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:237:in `block in iterate_until_no_changes'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:230:in `loop'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:230:in `iterate_until_no_changes'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:201:in `do_inspection_loop'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:111:in `block in file_offenses'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:121:in `file_offense_cache'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:109:in `file_offenses'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:100:in `process_file'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:78:in `block in each_inspected_file'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:75:in `each'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:75:in `reduce'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:75:in `each_inspected_file'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:67:in `inspect_files'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/runner.rb:39:in `run'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cli.rb:150:in `execute_runner'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cli.rb:78:in `execute_runners'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/lib/rubocop/cli.rb:38:in `run'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/bin/rubocop:13:in `block in <top (required)>'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/rubocop-0.52.1/bin/rubocop:12:in `<top (required)>'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/bin/rubocop:23:in `load'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/bin/rubocop:23:in `<top (required)>'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli/exec.rb:75:in `load'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli/exec.rb:75:in `kernel_load'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli/exec.rb:28:in `run'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli.rb:424:in `exec'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/vendor/thor/lib/thor.rb:387:in `dispatch'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli.rb:27:in `dispatch'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/vendor/thor/lib/thor/base.rb:466:in `start'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/cli.rb:18:in `start'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/exe/bundle:30:in `block in <top (required)>'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/lib/bundler/friendly_errors.rb:122:in `with_friendly_errors'
/Users/dominic/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/bundler-1.16.0/exe/bundle:22:in `<top (required)>'
/Users/dominic/.rbenv/versions/2.2.2/bin/bundle:23:in `load'
/Users/dominic/.rbenv/versions/2.2.2/bin/bundle:23:in `<main>'
.

1 file inspected, no offenses detected

1 error occurred:
An error occurred while Rails/Presence cop was inspecting /Users/dominic/tmp/a.rb:5:4.
Errors are usually caused by RuboCop bugs.
Please, report your problems to RuboCop's issue tracker.
Mention the following information in the issue report:
0.52.1 (using Parser 2.4.0.2, running on ruby 2.2.2 x86_64-darwin16)
Finished in 0.3389270000043325 seconds

RuboCop version

$ rubocop -V
0.52.1 (using Parser 2.4.0.2, running on ruby 2.2.2 x86_64-darwin16)

[dominicsayers]

cc @wata727