feat(macro): Adds custom derive attributes

[thomastaylor312]

This adds custom derive attributes to the generate macro. It also fixes a bug where package version was not appended to the hash map of exports

Closes #148

[thomastaylor312]

@peterhuene This is only draft because right now it is depending on a git dependency of wit-bindgen until 0.13 can be released. That release also combined two of the rust crates (see bytecodealliance/wit-bindgen#683), so I had to make those changes here as well. I did test this manually with some projects I was using, but let me know if I missed anything

[peterhuene]

The implementation looks great!

I think we should probably add a build test that applies a drive and tests it (like a simple serialization test).

[peterhuene]

Also, as this depends on an unreleased version of wit-bindgen, I'm going to hold off on merging until #147 is merged so that I can cut the first releases of the crates.

[thomastaylor312]

I think we should probably add a build test that applies a drive and tests it (like a simple serialization test).

@peterhuene I didn't add one because there is already a test in wit-bindgen that tests for this. Did you still want to add one here as a smoke test (just making sure it can compile with the additional_derives value set)?

[thomastaylor312]

Ok, added a test anyway @peterhuene

[peterhuene]

@peterhuene I didn't add one because there is already a test in wit-bindgen that tests for this. Did you still want to add one here as a smoke test (just making sure it can compile with the additional_derives value set)?

Yeah, it'd be good to have the test to cover that the argument to cargo_component_bindings::generate! actually works, in addition to the test coverage in wit-bindgen to ensure the generated bindings are correct.

Ok, added a test anyway @peterhuene

Thanks!

[thomastaylor312]

I'll leave this in draft to avoid accidental merge until either

a) You've cut a version of cargo-component to release the crate
b) wit-bindgen releases a new tagged version

[sehz]

Can we merge this? We are relying on this feature. Suggest having wit-bindgen as a git dependency since this is not published anyway.

[peterhuene]

I'm about to publish a 0.2.0 version of cargo-component and 0.1.0 version of the wit tools to crates.io.

When that is finished, we can merge this as-is with the git references, which will block any future release until we get a new wit-bindgen published.

[peterhuene]

We're now good to rebase this PR and change it from a draft; we don't need to wait for a wit-bindgen release.

[thomastaylor312]

Ok, I'll rebase!

[thomastaylor312]

@peterhuene This should be good to go

[peterhuene]

@thomastaylor312 thanks!