/usr/lib/ruby/vendor_ruby/rails/generators/test_unit/plugin/templates/test_helper.rb is in ruby-railties 2:4.2.6-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | require 'active_support/testing/autorun'
require 'active_support'
|