`derive` macros require `cargo` to be present about borsh-rs

[Fuuzetsu]

After surveying some popular crates, it seems that the general approach is to expose some crate = attribute that allows specifying the name explicitly: borsh already supports this I believe. Without it, just breaks if rename happens.

Only a few crates use proc-macro-crate helper that goes via cargo, especially because it makes the macro unpure (goes via filesystem...).

There doesn't seem to be a good solution other than these options...

[dj8yfo]

@Fuuzetsu looking up nix doc https://nixos.org/manual/nixpkgs/stable/#compiling-rust-crates-using-nix-instead-of-cargo, it looks like giving up cargo completely is a viable option.

#272 is one of possible ways to resolve this, if adding #[borsh(crate = "borsh")] everywhere, effectively disabling proc-macro-crate checks, isn't too ergonomic.

[Fuuzetsu]

@Fuuzetsu looking up nix doc https://nixos.org/manual/nixpkgs/stable/#compiling-rust-crates-using-nix-instead-of-cargo, it looks like giving up cargo completely is a viable option.

Hm? Not sure what you mean by this but right, we already do not use cargo during the build.

#272 is one of possible ways to resolve this, if adding #[borsh(crate = "borsh")] everywhere, effectively disabling proc-macro-crate checks, isn't too ergonomic.

Right, making it optional is something I guess. Presumably in cases where one renamed borsh and has a very large number of derives.

FWIW for now we're just using a fork with the proc-macro-crate deleted from the repo all together...

[frol]

@dj8yfo I don't think we need to introduce a breaking change to borsh-rs to accommodate non-standard use of build systems.

@Fuuzetsu Please, consider contributing to proc-macro-crate so it just supports your build environment.

P.S. I closed this issue to indicate that we don't plan to take any actions on it now as it is outside of the scope of this crate, but if you believe otherwise, please, feel free to comment below