Support nested fields in get and get_with attributes

[chinedufn]

Add support for a dot . notation that lets us expose nested fields.

For example, the following should be possible:

#[swift_bridge::bridge]
mod ffi {
   extern "Rust" {
        type SomeType;
       
        #[swift_bridge(get(field.another_field))]
        fn another_field(&self) -> u16;
   } 
}

pub struct SomeType {
    field: AnotherType
}

struct AnotherType {
    another_field: u16
}

[chinedufn]

Implementation Guide

Vec of fields

Change the field_name to be a Vec<Ident>

swift-bridge/crates/swift-bridge-ir/src/parsed_extern_fn.rs

Line 105 in 54b9c09

pub(crate) field_name: Ident,

swift-bridge/crates/swift-bridge-ir/src/parsed_extern_fn.rs

Line 111 in 54b9c09

pub(crate) field_name: Ident,

Parser Test

Add a get test that has a nested field

swift-bridge/crates/swift-bridge-ir/src/parse/parse_extern_mod/function_attributes.rs

Lines 450 to 481 in 3018fc2

	/// Verify that we can parse the `get` attribute.
	#[test]
	fn parses_get_attribute() {
	let tokens = quote! {
	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type Foo;
	#[swift_bridge(get(field))]
	fn some_function(&self);
	#[swift_bridge(get(&field))]
	fn some_function_ref(&self);
	#[swift_bridge(get(&mut field))]
	fn some_function_ref_mut(&mut self);
	}
	}
	};
	let module = parse_ok(tokens);
	let tests = vec![(false, false), (true, false), (true, true)];
	for (idx, (has_ref, has_mut)) in tests.into_iter().enumerate() {
	let funcs = &module.functions;
	let field = funcs[idx].get_field.as_ref().unwrap().unwrap_direct();
	assert_eq!(field.maybe_ref.is_some(), has_ref);
	assert_eq!(field.maybe_mut.is_some(), has_mut);
	}
	}

Add a get_with test that has a nested field

swift-bridge/crates/swift-bridge-ir/src/parse/parse_extern_mod/function_attributes.rs

Lines 483 to 514 in 3018fc2

	/// Verify that we can parse the `get_with` attribute.
	#[test]
	fn parses_get_with_attribute() {
	let tokens = quote! {
	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type Foo;
	#[swift_bridge(get_with(field = a::b::c))]
	fn some_function(&self);
	#[swift_bridge(get_with(&field = a::b::c))]
	fn some_function_ref(&self);
	#[swift_bridge(get_with(&mut field = a::b::c))]
	fn some_function_ref_mut(&mut self);
	}
	}
	};
	let module = parse_ok(tokens);
	let tests = vec![(false, false), (true, false), (true, true)];
	for (idx, (has_ref, has_mut)) in tests.into_iter().enumerate() {
	let funcs = &module.functions;
	let field = funcs[idx].get_field.as_ref().unwrap().unwrap_with();
	assert_eq!(field.maybe_ref.is_some(), has_ref);
	assert_eq!(field.maybe_mut.is_some(), has_mut);
	}
	}

Codegen Tests

Add a get test that has a nested field

swift-bridge/crates/swift-bridge-ir/src/codegen/codegen_tests/function_attribute_codegen_tests.rs

Lines 258 to 326 in 5b97b4a

	/// Verify that we can use the get attribute
	mod get {
	use super::*;
	fn bridge_module_tokens() -> TokenStream {
	quote! {
	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type SomeType;
	#[swift_bridge(get(field))]
	fn some_function(&self) -> u16;
	#[swift_bridge(get(&field))]
	fn some_function_ref(&self) -> i16;
	#[swift_bridge(get(&mut field))]
	fn some_function_ref_mut(&mut self) -> u8;
	}
	}
	}
	}
	fn expected_rust_tokens() -> ExpectedRustTokens {
	ExpectedRustTokens::ContainsMany(vec![
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function(
	this: *mut super::SomeType
	) -> u16 {
	(unsafe { &*this }).field
	}
	},
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function_ref(
	this: *mut super::SomeType
	) -> i16 {
	&(unsafe { &*this }).field
	}
	},
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function_ref_mut(
	this: *mut super::SomeType
	) -> u8 {
	&mut (unsafe { &mut *this }).field
	}
	},
	])
	}
	fn expected_swift_code() -> ExpectedSwiftCode {
	ExpectedSwiftCode::SkipTest
	}
	fn expected_c_header() -> ExpectedCHeader {
	ExpectedCHeader::SkipTest
	}
	#[test]
	fn get() {
	CodegenTest {
	bridge_module: bridge_module_tokens().into(),
	expected_rust_tokens: expected_rust_tokens(),
	expected_swift_code: expected_swift_code(),
	expected_c_header: expected_c_header(),
	}
	.test();
	}
	}

Add a get_with test that has a nested field

swift-bridge/crates/swift-bridge-ir/src/codegen/codegen_tests/function_attribute_codegen_tests.rs

Lines 328 to 396 in 5b97b4a

	/// Verify that we can use the get attribute
	mod get_with {
	use super::*;
	fn bridge_module_tokens() -> TokenStream {
	quote! {
	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type SomeType;
	#[swift_bridge(get_with(field = a::b::c))]
	fn some_function(&self);
	#[swift_bridge(get_with(&field = a::b::c))]
	fn some_function_ref(&self);
	#[swift_bridge(get_with(&mut field = a::b::c))]
	fn some_function_ref_mut(&mut self);
	}
	}
	}
	}
	fn expected_rust_tokens() -> ExpectedRustTokens {
	ExpectedRustTokens::ContainsMany(vec![
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function(
	this: *mut super::SomeType
	) {
	super::a::b::c( (unsafe { &*this }).field )
	}
	},
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function_ref(
	this: *mut super::SomeType
	) {
	super::a::b::c( & (unsafe { &*this }).field )
	}
	},
	quote! {
	pub extern "C" fn __swift_bridge__SomeType_some_function_ref_mut(
	this: *mut super::SomeType
	) {
	super::a::b::c( &mut (unsafe { &mut *this }).field )
	}
	},
	])
	}
	fn expected_swift_code() -> ExpectedSwiftCode {
	ExpectedSwiftCode::SkipTest
	}
	fn expected_c_header() -> ExpectedCHeader {
	ExpectedCHeader::SkipTest
	}
	#[test]
	fn get_with() {
	CodegenTest {
	bridge_module: bridge_module_tokens().into(),
	expected_rust_tokens: expected_rust_tokens(),
	expected_swift_code: expected_swift_code(),
	expected_c_header: expected_c_header(),
	}
	.test();
	}
	}

Integration Tests

Add a get function that has a nested field

swift-bridge/crates/swift-integration-tests/src/function_attributes/get.rs

Lines 1 to 18 in 580f522

	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type SomeTypeGet;
	#[swift_bridge(init)]
	fn new() -> SomeTypeGet;
	#[swift_bridge(get(my_u8))]
	fn my_u8(&self) -> u8;
	#[swift_bridge(get(&my_string))]
	fn my_string_reference(&self) -> &str;
	#[swift_bridge(get(my_opt_static_str))]
	fn my_opt_static_str(&self) -> Option<&'static str>;
	}
	}

Add a get_with function that has a nested field

swift-bridge/crates/swift-integration-tests/src/function_attributes/get_with.rs

Lines 3 to 20 in 78be911

	#[swift_bridge::bridge]
	mod ffi {
	extern "Rust" {
	type SomeTypeGetWith;
	// Returns ui_to_i16(self.my_u8)
	#[swift_bridge(get_with(my_u8 = u8_to_i16))]
	fn my_u8_converted(&self) -> i16;
	// Returns Clone::clone(&self.my_string)
	#[swift_bridge(get_with(&my_string = Clone::clone))]
	fn my_string_cloned(&self) -> String;
	// Returns string_to_u32(&self.my_string)
	#[swift_bridge(get_with(&my_string = string_to_u32))]
	fn my_string_parsed(&self) -> u32;
	}
	}

Get Tests Passing

Once all of the tests are passing and the crates/swift-integration-tests can successfully compile then this issue is complete.