/usr/ is in ruby-rack-test 0.6.2-3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/rack/
/usr/lib/ruby/vendor_ruby/rack/test.rb
/usr/lib/ruby/vendor_ruby/rack/test/
/usr/lib/ruby/vendor_ruby/rack/test/cookie_jar.rb
/usr/lib/ruby/vendor_ruby/rack/test/uploaded_file.rb
/usr/lib/ruby/vendor_ruby/rack/test/mock_digest_request.rb
/usr/lib/ruby/vendor_ruby/rack/test/methods.rb
/usr/lib/ruby/vendor_ruby/rack/test/utils.rb
/usr/lib/ruby/vendor_ruby/rack/mock_session.rb
/usr/share/
/usr/share/doc/
/usr/share/doc/ruby-rack-test/
/usr/share/doc/ruby-rack-test/README.rdoc
/usr/share/doc/ruby-rack-test/changelog.gz
/usr/share/doc/ruby-rack-test/copyright
/usr/share/doc/ruby-rack-test/changelog.Debian.gz
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/rack-test-0.6.2.gemspec