Add a comment pointing to the Rust source file

[jtwaleson]

I have my frontend and backend in one repo, and would like to see the source of an auto-generated typescript definition.

Something like:

// This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.

// source: file://./../../backend/src/my_enum.rs

export type MyEnum = "A" | "B"

This way I can click in my IDE to go to the correct place, and also any AI coding agents can quickly jump to the correct file to see where this is leading into the backend.

I tried to get this to work in ts-rs but struggled as I'm still a bit new to Rust and it seems that source path information is not easily accessible in macros.

So for now, two questions:

• is this a good idea?
• if so: how could we make it work?

[gustavo-shigueo]

Hello @jtwaleson!

This is an interesting feature, but I think it would make collaboration more difficult

is this a good idea?

If the Rust and TS codebases are in separate git repos, the relative paths will likely be different between devs working on these repos, which will mean the path won't make sense for some and if the TS bindings are checked into git that will cause unnecessary changes - this could potentially be solved by exporting the type's module path instead (crate::some::where) but that would still cause unnecessary git changes if a type is moved from one module to another

if so: how could we make it work?

It could probably work by emitting module_path in some new method in the TS trait, I haven't actually tested this at all, so I don't know if it'd actually work (I just stole the idea from one of @NyxCode's comments lol)

But there's another way to achieve this: documentation comments

If you document you rust types with doc comments (/// ...), ts-rs will convert them into JSDoc comments, so you could embed the desired file path into a doc comment and it will show up in your TS file

[NyxCode]

I share @gustavo-shigueo's concern about portability of file paths, especially when used in libraries.
I think you could make this work with #[doc], something like

#[derive(TS)]
#[ts(export)]
#[doc = concat!("defined in file ", file!())]
struct MyStruct;

[jtwaleson]

Thanks for your insights. Indeed, it should definitely be configurable per project as it's not one-size-fits-all.

@NyxCode your suggestion seems great, but currently gives doc with non literal expression found

[NyxCode]

Ah, that's unfortunate. Seems like we only support literals in that position. That's definitely something we should add support for - I'll open a PR!

[NyxCode]

If you find some time, feel free to give #411 a try

[jtwaleson]

I think it would have worked fine, but I'm switching to https://github.com/juhaku/utoipa as I want full OpenAPI generation. Was trying out both approaches for a couple of days. Your suggestion for comments in Rustdocs worked there too, so it's up and running now. Thanks!