Add ability to rename functions bound to Godot

[you-win]

• Modify func macro to accept a 'rename = ...' attribute
• Add integration tests to cover renamed functions

Comments

Please let me know if it would be better to break this functionality out like with field_var.rs. I tried to keep the number of changed files to a minimum.

There are also TODOs left in the file as a starting point for discussion, but feel free to start picking at the PR wherever you want.

Still missing

• signal renaming
• docs
• unit tests?

[GodotRust]

API docs are being generated and will be shortly available at: https://godot-rust.github.io/docs/gdext/pr-376

[Bromeon]

Thanks a lot! This is a nice addition 🙂

I commented on a few things to simplify code flow. Some parts of it are related more to existing code that is now updated, rather than your code in particular.

Also thanks for the tests!

[Bromeon]

If that refactoring is possible (method registration reusing the struct), could you do it right away?

Maybe name the struct Func or FuncDefinition or so, rather than GodotFn.

[you-win]

I have created a new FuncDefinition struct in method_registration/mod.rs

[Bromeon]

I'd probably keep this as a separate type, as the possible options for #[func] and #[signal] likely diverge over time. It also slightly enhances type safety.

Signal renames are not yet supported as far as I can see, so they should not have this field.

[you-win]

Is it not worth it to rename the type for a bit more clarity in the method signature for?

fn process_godot_fns(decl: &mut Impl) -> Result<(Vec<FuncDefinition>, Vec<Signal>), Error>

vs

fn process_godot_fns(decl: &mut Impl) -> Result<(Vec<FuncDefinition>, Vec<Function>), Error>

[Bromeon]

The code flow gets a bit weird (not your code, but the result of the existing one growing).

We do this at the moment:

for attribute in all_attributes {
   match attribute {
       "func" => KvParser::parse(all_attributes) // again searching through all
       "signal" => ...
   }
}

detect_duplicates(); // custom validation that's less expressive than KvParser's built-in one

Whereas KvParser is designed to already extract the relevant attributes and check for unhandled/duplicate/leftover ones in the finish() call. So you could do this:

if let Some(mut parser) = KvParser::parse(attributes, "func")? {
    // handle #[func]
    
    // eventually:
    parser.finish();
}

if let Some(_) = KvParser::parse(attributes, "signal")? {
    // handle #[signal]
}

Do you think this could be done?

[you-win]

This is in progress, my latest WIP code does not work properly since it picks up other annotations first.

Currently, it's picking up #[allow(clippy::uninlined_format_args)], but I will continue to poke at it.

[Bromeon]

Replaced by #378.