Prefix idents that don't start with an alphabetic character

[LegNeato]

[LucioFranco]

Hi @LegNeato do you know of any precedent on how other protobuf implementations handle this?

[LegNeato]

I do not, I can look into it though. I think if the find & replace infra was a bit more robust this wouldn't be necessary. I'll look into a larger patch as well as what other impls do

[LegNeato]

Ok, I looked into how protoc handles this. It is a mess! Every language does different things and there is a bunch of undocumented behavior.

This is a problem because prost strips enum prefixes, which turns a valid identifier field name to an invalid identifier. But, similar issues can arise with rust restricted keywords (there are a ton of protoc issues where people have valid idents in one language that are reserved in another, chaos ensues).

[danburkert]

Please also add a test to fn test_ident_conversions/ident_conversion.proto's StrawberryRhubarbPIE

[LegNeato]

I plan to get to this in the next couple of days, thanks @danburkert for the review!

[LegNeato]

@danburkert Sorry this took so long, thank you again for the review.

[LucioFranco]

@LegNeato seems need to fix the rustfmt ci stage

[LegNeato]

@LucioFranco whoops, done.

[caspermeijn]

This has recently been fixed by https://github.com/tokio-rs/prost/pull/998