Vec of shared struct

[smolck]

Currently something like the following Swift code:

class Test {
    func testFunction(things: RustVec<Thing>) { /* Do stuff */ }
}

and this Rust code:

#[swift_bridge::bridge]
mod ffi {
    #[swift_bridge(swift_repr = "struct")]
    pub struct Thing {
        pub some_str: String
    }

    extern "Swift" {
        type Test;

        #[swift_bridge(init)]
        fn new() -> Test;

        fn testFunction(&self, things: Vec<Thing>);
    }
}

// Then somewhere else
let test = ffi::Test::new();
test.testFunction(vec![Thing { some_str: "foo".to_string() }, /* ... */]);

doesn't work, evidently due to the shared struct Thing not implmenting Vectorizable on the Swift side. Am I missing something and this sort of thing is possible? If not, could support for this be added?

[chinedufn]

Hey.

Yup you're right that Vec<SharedStruct> isn't implemented yet. You aren't missing anything.

Right now we only support Vec<OpaqueRustType>

https://github.com/chinedufn/swift-bridge/blob/4d0a18f698c8244e874337f6fc9644b13f037e92/crates/swift-bridge-ir/src/codegen/codegen_tests/vec_codegen_tests.rs#L226-L236

https://github.com/chinedufn/swift-bridge/blob/b26dcf9c307d0bf77af96d5c29a6a479ad179a88/crates/swift-integration-tests/src/vec.rs#L1-L17

https://github.com/chinedufn/swift-bridge/blob/b26dcf9c307d0bf77af96d5c29a6a479ad179a88/SwiftRustIntegrationTestRunner/SwiftRustIntegrationTestRunnerTests/VecTests.swift#L72-L81

---

Normally I'd try to get this to you right away but I'm pushing up against a deadline right now.

I can implement support for this over the weekend if that works for you?

Otherwise if it's urgent I'd be happy to provide guidance on how to implement this.

---

Thanks for opening this issue!

[smolck]

I can implement support for this over the weekend if that works for you?

Yes that’d be great! Thank you!

[oeed]

I'm in need of this too, would be awesome to get added!

[oeed]

@chinedufn this is blocking me currently so I'd be happy to try and implement, do you have any pointers as to how to do so?

[chinedufn]

Hey! Thanks for the heads up. I'll write up some detailed instructions either tonight or tomorrow.

[chinedufn]

Hey. Sorry I'll have to get to this today or tomorrow! Will definitely write these for you just need to finish a couple more unrelated things. Thanks!

[chinedufn]

Thanks for waiting! I've written up a guide to adding support for Vec<TransparentStruct>. Please let me know if you have any questions and I'll be more than happy to help.

Implementing Support for Vec<TransparentStruct>

Background

• Read the docs on adding support for a new signature https://chinedufn.github.io/swift-bridge/contributing/adding-support-for-a-signature/index.html

• Read some of the existing Vec tests

  • https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/SwiftRustIntegrationTestRunner/SwiftRustIntegrationTestRunnerTests/VecTests.swift#L11
  • https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-bridge-ir/src/codegen/codegen_tests/vec_codegen_tests.rs#L7-L20

Integration Tests

Add an integration test for Vec<TransparentStruct>.

You can use Vec<TransparentEnum> as a guide:

• https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/SwiftRustIntegrationTestRunner/SwiftRustIntegrationTestRunnerTests/VecTests.swift#L84-L94
• https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-integration-tests/src/vec.rs#L23-L27

Codegen Tests

Add codegen tests, similar to the ones for transparent enums

• https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-bridge-ir/src/codegen/codegen_tests/vec_codegen_tests.rs#L282-L423
• https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-bridge-ir/src/codegen/codegen_tests/vec_codegen_tests.rs#L425-L479
• https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-bridge-ir/src/codegen/codegen_tests/vec_codegen_tests.rs#L481-L538

Vec support tests

• Add a mod vec_of_transparent_struct

  • https://github.com/chinedufn/swift-bridge/blob/c1fd7177b5d3a8918e34b6bc96ae29437cfc1487/crates/swift-bridge-ir/src/codegen/generate_rust_tokens/vec.rs#L1-L2

• Model it after the mod vec_of_transparent_enum

  • https://github.com/chinedufn/swift-bridge/blob/819e39160ec5b38dce2e60e2d39d078617ad158d/crates/swift-bridge-ir/src/codegen/generate_rust_tokens/vec/vec_of_transparent_enum.rs#L5-L12

• Same idea with the Swift impl

  • https://github.com/chinedufn/swift-bridge/blob/72e1759e0504e3a5a32587605c98e410f12ea9e7/crates/swift-bridge-ir/src/codegen/generate_swift/shared_enum.rs#L71-L102

Getting everything working

You should be able to run the tests and tweak code in https://github.com/chinedufn/swift-bridge/blob/2bffcb08c1f0ca8bbcba9c78c5ae28a9cddfb632/crates/swift-bridge-ir/src/bridged_type.rs until the tests pass

[antoniusnaumann]

If there is currently nobody working on this, I would like to try to implement this (probably next week).

[chinedufn]

All yours! Please don’t hesitate to ask questions here if you have any.

[antoniusnaumann]

All yours!

Please don’t hesitate to ask questions here if you have any.

Unfortunately I got some project deadlines the next weeks that require more work than expected, so I am not able to start working on this any time soon.