gistfile1.txt

$ ack -ri "Test::Unit" *
actionpack/lib/action_controller/test_case.rb
308:  # Test::Unit::TestCase and define @controller, @request, @response in +setup+.)

activesupport/lib/active_support/inflector/methods.rb
205:    #   'Test::Unit'.constantize # => Test::Unit
249:    #   'Test::Unit'.safe_constantize # => Test::Unit

activesupport/lib/active_support/test_case.rb
20:  class TestCase < ::MiniTest::Unit::TestCase

activesupport/lib/active_support/testing/autorun.rb
5:MiniTest::Unit.autorun

activesupport/lib/active_support/testing/isolation.rb
20:        e = Test::Unit::Error.new(e.test_name, RemoteError.new(e.exception))

railties/lib/rails/generators/app_base.rb
62:                                          desc: 'Skip Test::Unit files'