undefined method `source' for nil:NilClass
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/style/zero_length_predicate.rb:65:in `replacement'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/style/zero_length_predicate.rb:57:in `block in autocorrect'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/corrector.rb:57:in `call'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/corrector.rb:57:in `block (2 levels) in rewrite'
/Users/david/.rvm/gems/ruby-2.2.3/gems/parser-2.3.1.0/lib/parser/source/rewriter.rb:194:in `transaction'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/corrector.rb:56:in `block in rewrite'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/corrector.rb:54:in `each'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/corrector.rb:54:in `rewrite'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/team.rb:132:in `autocorrect_all_cops'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/team.rb:105:in `autocorrect'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cop/team.rb:60:in `inspect_file'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:205:in `inspect_file'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:175:in `block in do_inspection_loop'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:165:in `loop'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:165:in `do_inspection_loop'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:87:in `process_file'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:59:in `block in inspect_files'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:57:in `each'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:57:in `inspect_files'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/runner.rb:35:in `run'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/lib/rubocop/cli.rb:30:in `run'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/bin/rubocop:14:in `block in <top (required)>'
/Users/david/.rvm/rubies/ruby-2.2.3/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
/Users/david/.rvm/gems/ruby-2.2.3/gems/rubocop-0.40.0/bin/rubocop:13:in `<top (required)>'
/Users/david/.rvm/gems/ruby-2.2.3/bin/rubocop:23:in `load'
/Users/david/.rvm/gems/ruby-2.2.3/bin/rubocop:23:in `<main>'
Inspecting 21 files
.....

5 files inspected, no offenses detected