Appetite for ".proto" file parser?

[jeffparsons]

Related: #486

I have two questions in mind:

• Would the Prost maintainers be interested in having a proto file parser in-tree, or is this too far outside the scope of the project?
• Would many Prost users (or just anyone working at the intersection of Rust and Protobufs, really) be interested in having a standalone proto file parser crate?

My primary use case involves custom code generation for several different languages (and docs, etc.). Currently this is achieved using a combination of protoc plugins (written in C++) and a fork of ruby-protoc, all glued together with some rather awkward Rake tasks.

I imagine using something like Chumsky and exposing a library interface and CLI tool. I would aim for bug-for-bug compatibility with the official protoc to the extent that is practicable.

Does this idea appeal to anyone?

[andrewhickman]

I've developed a crate for this: protox which I think pretty much matches what you describe. It aims for equivalent output to protoc on all valid protobuf files.

I also pulled out the parser into its own crate protox-parse purely because the API is so small.