Proto3 Field Presence

[sneako]

First off, thanks for the great library! In my initial testing, it offers the best performance out of our options in the BEAM ecosystem, and I appreciate the property and mutation tests!

It appears that they have added field presence to proto3, so now it is possible again (as it was in proto2) to distinguish between a value that was not set at all and a value that was set to the default value.

See:

https://github.com/protocolbuffers/protobuf/blob/master/docs/field_presence.md
https://github.com/protocolbuffers/protobuf/blob/master/docs/implementing_proto3_presence.md
protocolbuffers/protobuf#1606

Would you be interested in either adding this feature to Protox or accepting a PR?

[ahamez]

Thank you, it's always nice to know that this library can be of some help 🙂!

I've been thinking about implementing this for a while, even though I didn't write anything yet (I don't think it's too much work , if I understood correctly, it just a matter of mapping optional to a synthetic oneof). So yes, I would be very interested in having this feature!

However, I don't know when I will be able to work seriously on this topic. So, if you think you can come up with a PR, I would gladly accept it! Otherwise, I'll do my best to add this feature, but I can't make any promise on the schedule.

[sneako]

Great! I took a look around codebase and I agree it doesn't seem like it should be too hard to implement. I'll take stab at it 😄

[ahamez]

Thank you! Don't hesitate if you have any question!