BridgeJS: Unify @JS struct parameter lowering onto the stack ABI

Plugins/BridgeJS/Sources/BridgeJSCore/ImportTS.swift

@@ -933,19 +933,10 @@ extension BridgeType {
  case .associatedValueEnum:
  return LoweringParameterInfo(loweredParameters: [("caseId", .i32)])
  case .swiftStruct:
- switch context {
- case .importTS:
- // Swift structs are bridged as JS objects (object IDs) in imported signatures.
- return LoweringParameterInfo(loweredParameters: [("objectId", .i32)])
- case .exportSwift:
- return LoweringParameterInfo(loweredParameters: [])
- }
+ // `@JS struct` parameters always use the stack ABI (same as arrays/dictionaries).
+ return LoweringParameterInfo(loweredParameters: [])
  case .namespaceEnum:
  throw BridgeJSCoreError("Namespace enums cannot be used as parameters")
- case .nullable(.swiftStruct, _) where context == .importTS:
- // Optional `@JS struct`s bridge through the stack (isSome discriminator + fields),
- // like optional arrays/dictionaries, rather than the non-optional object-id ABI.
- return LoweringParameterInfo(loweredParameters: [("isSome", .i32)])
  case .nullable(let wrappedType, _):
  let wrappedInfo = try wrappedType.loweringParameterInfo(context: context)
  var params = [("isSome", WasmCoreType.i32)]
@@ -1005,24 +996,16 @@ extension BridgeType {
  case .associatedValueEnum:
  return LiftingReturnInfo(valueToLift: .i32)
  case .swiftStruct:
- switch context {
- case .importTS:
- // Swift structs are bridged as JS objects (object IDs) in imported signatures.
- return LiftingReturnInfo(valueToLift: .i32)
- case .exportSwift:
- return LiftingReturnInfo(valueToLift: nil)
- }
+ // `@JS struct` returns always use the stack ABI (same as arrays/dictionaries).
+ return LiftingReturnInfo(valueToLift: nil)
  case .namespaceEnum:
  throw BridgeJSCoreError("Namespace enums cannot be used as return values")
  case .nullable(let wrappedType, _):
- // jsObject and `@JS struct` use the stack ABI for optionals — the thunk returns
- // void and the value (plus isSome discriminator) flows through the stacks.
+ // jsObject uses the stack ABI for optionals — the thunk returns void and the
+ // value (plus isSome discriminator) flows through the stacks.
  if case .jsObject = wrappedType {
  return LiftingReturnInfo(valueToLift: nil)
  }
- if case .swiftStruct = wrappedType, context == .importTS {
- return LiftingReturnInfo(valueToLift: nil)
- }
  let wrappedInfo = try wrappedType.liftingReturnInfo(context: context)
  return LiftingReturnInfo(valueToLift: wrappedInfo.valueToLift)
  case .array, .dictionary:

Plugins/BridgeJS/Sources/BridgeJSLink/JSGlueGen.swift

@@ -1437,23 +1437,18 @@ struct IntrinsicJSFragment: Sendable {
  }
  )
  case .swiftStruct(let fullName):
- switch context {
- case .importTS:
- return .jsObjectLiftRetainedObjectId
- case .exportSwift:
- let base = fullName.replacingOccurrences(of: ".", with: "_")
- return IntrinsicJSFragment(
- parameters: [],
- printCode: { arguments, context in
- let (scope, printer) = (context.scope, context.printer)
- let resultVar = scope.variable("structValue")
- printer.write(
- "const \(resultVar) = \(JSGlueVariableScope.reservedStructHelpers).\(base).lift();"
- )
- return [resultVar]
- }
- )
- }
+ let base = fullName.replacingOccurrences(of: ".", with: "_")
+ return IntrinsicJSFragment(
+ parameters: [],
+ printCode: { arguments, context in
+ let (scope, printer) = (context.scope, context.printer)
+ let resultVar = scope.variable("structValue")
+ printer.write(
+ "const \(resultVar) = \(JSGlueVariableScope.reservedStructHelpers).\(base).lift();"
+ )
+ return [resultVar]
+ }
+ )
  case .closure:
  return IntrinsicJSFragment(
  parameters: ["funcRef"],
@@ -1497,12 +1492,7 @@ struct IntrinsicJSFragment: Sendable {
  case .associatedValueEnum(let fullName):
  return associatedValueLowerReturn(fullName: fullName)
  case .swiftStruct(let fullName):
- switch context {
- case .importTS:
- return .jsObjectLowerReturn
- case .exportSwift:
- return swiftStructLowerReturn(fullName: fullName)
- }
+ return swiftStructLowerReturn(fullName: fullName)
  case .closure:
  return IntrinsicJSFragment(
  parameters: ["value"],

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/Async.swift

@@ -507,20 +507,20 @@ func _$Promise_resolve_8JSObjectC(_ promise: JSObject, _ value: JSObject) throws
 
 #if arch(wasm32)
 @_extern(wasm, module: "bjs", name: "promise_resolve_TestModule_10AsyncPointV")
-fileprivate func promise_resolve_TestModule_10AsyncPointV_extern(_ promise: Int32, _ value: Int32) -> Void
+fileprivate func promise_resolve_TestModule_10AsyncPointV_extern(_ promise: Int32) -> Void
 #else
-fileprivate func promise_resolve_TestModule_10AsyncPointV_extern(_ promise: Int32, _ value: Int32) -> Void {
+fileprivate func promise_resolve_TestModule_10AsyncPointV_extern(_ promise: Int32) -> Void {
  fatalError("Only available on WebAssembly")
 }
 #endif
-@inline(never) fileprivate func promise_resolve_TestModule_10AsyncPointV(_ promise: Int32, _ value: Int32) -> Void {
- return promise_resolve_TestModule_10AsyncPointV_extern(promise, value)
+@inline(never) fileprivate func promise_resolve_TestModule_10AsyncPointV(_ promise: Int32) -> Void {
+ return promise_resolve_TestModule_10AsyncPointV_extern(promise)
 }
 
 func _$Promise_resolve_10AsyncPointV(_ promise: JSObject, _ value: AsyncPoint) throws(JSException) -> Void {
- let valueObjectId = value.bridgeJSLowerParameter()
+ let _ = value.bridgeJSLowerParameter()
  let promiseValue = promise.bridgeJSLowerParameter()
- promise_resolve_TestModule_10AsyncPointV(promiseValue, valueObjectId)
+ promise_resolve_TestModule_10AsyncPointV(promiseValue)
  if let error = _swift_js_take_exception() { throw error }
 }
 

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/SwiftClosure.swift

@@ -2684,20 +2684,20 @@ func _$Promise_resolve_SS(_ promise: JSObject, _ value: String) throws(JSExcepti
 
 #if arch(wasm32)
 @_extern(wasm, module: "bjs", name: "promise_resolve_TestModule_6AnimalV")
-fileprivate func promise_resolve_TestModule_6AnimalV_extern(_ promise: Int32, _ value: Int32) -> Void
+fileprivate func promise_resolve_TestModule_6AnimalV_extern(_ promise: Int32) -> Void
 #else
-fileprivate func promise_resolve_TestModule_6AnimalV_extern(_ promise: Int32, _ value: Int32) -> Void {
+fileprivate func promise_resolve_TestModule_6AnimalV_extern(_ promise: Int32) -> Void {
  fatalError("Only available on WebAssembly")
 }
 #endif
-@inline(never) fileprivate func promise_resolve_TestModule_6AnimalV(_ promise: Int32, _ value: Int32) -> Void {
- return promise_resolve_TestModule_6AnimalV_extern(promise, value)
+@inline(never) fileprivate func promise_resolve_TestModule_6AnimalV(_ promise: Int32) -> Void {
+ return promise_resolve_TestModule_6AnimalV_extern(promise)
 }
 
 func _$Promise_resolve_6AnimalV(_ promise: JSObject, _ value: Animal) throws(JSException) -> Void {
- let valueObjectId = value.bridgeJSLowerParameter()
+ let _ = value.bridgeJSLowerParameter()
  let promiseValue = promise.bridgeJSLowerParameter()
- promise_resolve_TestModule_6AnimalV(promiseValue, valueObjectId)
+ promise_resolve_TestModule_6AnimalV(promiseValue)
  if let error = _swift_js_take_exception() { throw error }
 }
 

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/SwiftStructImports.swift

@@ -48,25 +48,25 @@ fileprivate func _bjs_struct_lift_Point_extern() -> Int32 {
 
 #if arch(wasm32)
 @_extern(wasm, module: "TestModule", name: "bjs_translate")
-fileprivate func bjs_translate_extern(_ point: Int32, _ dx: Int32, _ dy: Int32) -> Int32
+fileprivate func bjs_translate_extern(_ dx: Int32, _ dy: Int32) -> Void
 #else
-fileprivate func bjs_translate_extern(_ point: Int32, _ dx: Int32, _ dy: Int32) -> Int32 {
+fileprivate func bjs_translate_extern(_ dx: Int32, _ dy: Int32) -> Void {
  fatalError("Only available on WebAssembly")
 }
 #endif
-@inline(never) fileprivate func bjs_translate(_ point: Int32, _ dx: Int32, _ dy: Int32) -> Int32 {
- return bjs_translate_extern(point, dx, dy)
+@inline(never) fileprivate func bjs_translate(_ dx: Int32, _ dy: Int32) -> Void {
+ return bjs_translate_extern(dx, dy)
 }
 
 func _$translate(_ point: Point, _ dx: Int, _ dy: Int) throws(JSException) -> Point {
  let dyValue = dy.bridgeJSLowerParameter()
  let dxValue = dx.bridgeJSLowerParameter()
- let pointObjectId = point.bridgeJSLowerParameter()
-let ret = bjs_translate(pointObjectId, dxValue, dyValue)
+ let _ = point.bridgeJSLowerParameter()
+ bjs_translate(dxValue, dyValue)
  if let error = _swift_js_take_exception() {
  throw error
  }
- return Point.bridgeJSLiftReturn(ret)
+ return Point.bridgeJSLiftReturn()
 }
 
 #if arch(wasm32)

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/Async.js

@@ -280,11 +280,10 @@ export async function createInstantiator(options, swift) {
  setException(error);
  }
  }
- bjs["promise_resolve_TestModule_10AsyncPointV"] = function(promise, value) {
+ bjs["promise_resolve_TestModule_10AsyncPointV"] = function(promise) {
  try {
- const value1 = swift.memory.getObject(value);
- swift.memory.release(value);
- swift.memory.getObject(promise)[__bjs_promiseSettlers].resolve(value1);
+ const structValue = structHelpers.AsyncPoint.lift();
+ swift.memory.getObject(promise)[__bjs_promiseSettlers].resolve(structValue);
  } catch (error) {
  setException(error);
  }

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/SwiftClosure.js

@@ -345,11 +345,10 @@ export async function createInstantiator(options, swift) {
  setException(error);
  }
  }
- bjs["promise_resolve_TestModule_6AnimalV"] = function(promise, value) {
+ bjs["promise_resolve_TestModule_6AnimalV"] = function(promise) {
  try {
- const value1 = swift.memory.getObject(value);
- swift.memory.release(value);
- swift.memory.getObject(promise)[__bjs_promiseSettlers].resolve(value1);
+ const structValue = structHelpers.Animal.lift();
+ swift.memory.getObject(promise)[__bjs_promiseSettlers].resolve(structValue);
  } catch (error) {
  setException(error);
  }

Plugins/BridgeJS/Tests/BridgeJSToolTests/__Snapshots__/BridgeJSLinkTests/SwiftStructImports.js

@@ -223,12 +223,11 @@ export async function createInstantiator(options, swift) {
  }
  bjs["swift_js_closure_unregister"] = function(funcRef) {}
  const TestModule = importObject["TestModule"] = importObject["TestModule"] || {};
- TestModule["bjs_translate"] = function bjs_translate(point, dx, dy) {
+ TestModule["bjs_translate"] = function bjs_translate(dx, dy) {
  try {
- const value = swift.memory.getObject(point);
- swift.memory.release(point);
- let ret = imports.translate(value, dx, dy);
- return swift.memory.retain(ret);
+ const structValue = structHelpers.Point.lift();
+ let ret = imports.translate(structValue, dx, dy);
+ structHelpers.Point.lower(ret);
  } catch (error) {
  setException(error);
  }

Sources/JavaScriptKit/BridgeJSIntrinsics.swift

@@ -1133,13 +1133,12 @@ where StackLiftResult == Self {
 }
 
 extension _BridgedSwiftStruct {
- @_spi(BridgeJS) public consuming func bridgeJSLowerParameter() -> Int32 {
- return toJSObject().bridgeJSLowerReturn()
- }
-
- @_spi(BridgeJS) public static func bridgeJSLiftReturn(_ objectId: Int32) -> Self {
- let jsObject = JSObject.bridgeJSLiftReturn(objectId)
- return Self(unsafelyCopying: jsObject)
+ /// Lower a struct parameter onto the shared stacks for the peer to `lift()`.
+ ///
+ /// Same convention as arrays/dictionaries. Use ``toJSObject()`` when a real JS object
+ /// representation is needed (e.g. `init(unsafelyCopying:)` round-trips).
+ @_spi(BridgeJS) public consuming func bridgeJSLowerParameter() {
+ bridgeJSStackPush()
  }
 
  @_spi(BridgeJS) public static func bridgeJSLiftReturn() -> Self {

Tests/BridgeJSRuntimeTests/ExportAPITests.swift

@@ -1339,6 +1339,15 @@ enum GraphOperations {
  let noneStr = none.map { "(\($0.dx),\($0.dy))" } ?? "nil"
  return "\(someStr) | \(noneStr)"
  }
+
+ /// Swift→JS callback with a struct parameter (ExportSwift stack ABI).
+ @JS func observeVector(_ callback: (Vector2D) -> Void) {
+ callback(Vector2D(dx: 1.5, dy: 2.5))
+ }
+
+ @JS func mapVector(_ vector: Vector2D, _ callback: (Vector2D) -> Vector2D) -> Vector2D {
+ return callback(vector)
+ }
 }
 
 @JS enum NestedStructGroupA {