* testing(perms): Add Parse fuzz test
I ran this for a few minutes and it didn't discover anything catastrophic.
* Add roundtrip tests
* Fix invalid unicode parsing, empty output fields
* Do the unicode conversion once on input
* Remove incorrect fix for empty output fields
* Allow empty output_fields
This is the same behavior as output_fields=,
* Add tests back, make JSON behaviour consistent
* Rework the output fields mechanism to fix some bugs such as properly handling no fields
* Change signature of Fields
Co-authored-by: Jeff Mitchell <jeffrey.mitchell@gmail.com>