rubocop --auto-correct raises undefined method error.

[tmtm]

Expected behavior

Don't raise error.

Actual behavior

rubocop raises undefined method error.

Steps to reproduce the problem

% cat sample.rb 
!str.empty? ? 123 : 456
% rubocop sample.rb 
Inspecting 1 file
C

Offenses:

sample.rb:1:1: C: Favor  over  for negative conditions.
!str.empty? ? 123 : 456
^^^^^^^^^^^^^^^^^^^^^^^

1 file inspected, 1 offense detected
% rubocop --auto-correct sample.rb
Inspecting 1 file


0 files inspected, no offenses detected
undefined method `keyword' for #<Parser::Source::Map::Ternary:0x000000025d4a10>
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/mixin/negative_conditional.rb:30:in `block in negative_conditional_corrector'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/corrector.rb:56:in `block (2 levels) in rewrite'
/tmp/gem/gems/parser-2.3.3.1/lib/parser/source/rewriter.rb:194:in `transaction'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/corrector.rb:55:in `block in rewrite'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/corrector.rb:53:in `each'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/corrector.rb:53:in `rewrite'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:140:in `autocorrect_all_cops'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:77:in `autocorrect'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:105:in `block in offenses'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:122:in `investigate'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:101:in `offenses'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cop/team.rb:51:in `inspect_file'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:248:in `inspect_file'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:195:in `block in do_inspection_loop'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:227:in `block in iterate_until_no_changes'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:220:in `loop'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:220:in `iterate_until_no_changes'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:191:in `do_inspection_loop'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:101:in `block in file_offenses'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:111:in `file_offense_cache'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:99:in `file_offenses'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:90:in `process_file'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:68:in `block in each_inspected_file'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:65:in `each'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:65:in `reduce'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:65:in `each_inspected_file'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:57:in `inspect_files'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/runner.rb:36:in `run'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cli.rb:72:in `execute_runner'
/tmp/gem/gems/rubocop-0.47.0/lib/rubocop/cli.rb:27:in `run'
/tmp/gem/gems/rubocop-0.47.0/bin/rubocop:13:in `block in <top (required)>'
/usr/lib/ruby/2.3.0/benchmark.rb:308:in `realtime'
/tmp/gem/gems/rubocop-0.47.0/bin/rubocop:12:in `<top (required)>'
/tmp/gem/bin/rubocop:23:in `load'
/tmp/gem/bin/rubocop:23:in `<main>'

RuboCop version

0.47.0 (using Parser 2.3.3.1, running on ruby 2.3.1 x86_64-linux-gnu)