swiftwasm · kateinoigakukun · Jun 11, 2026 · Jun 10, 2026 · Jun 10, 2026 · Jun 10, 2026
diff --git a/Plugins/BridgeJS/Sources/BridgeJSCore/ImportTS.swift b/Plugins/BridgeJS/Sources/BridgeJSCore/ImportTS.swift
@@ -936,12 +936,7 @@ extension BridgeType {
            let wasmType = rawType.wasmCoreType ?? .i32
            return LoweringParameterInfo(loweredParameters: [("value", wasmType)])
        case .associatedValueEnum:
-            switch context {
-            case .importTS:
-                throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
-            case .exportSwift:
-                return LoweringParameterInfo(loweredParameters: [("caseId", .i32)])
-            }
+            return LoweringParameterInfo(loweredParameters: [("caseId", .i32)])
        case .swiftStruct:
            switch context {
            case .importTS:
@@ -1011,12 +1006,7 @@ extension BridgeType {
            let wasmType = rawType.wasmCoreType ?? .i32
            return LiftingReturnInfo(valueToLift: wasmType)
        case .associatedValueEnum:
-            switch context {
-            case .importTS:
-                throw BridgeJSCoreError("Enum types are not yet supported in TypeScript imports")
-            case .exportSwift:
-                return LiftingReturnInfo(valueToLift: .i32)
-            }
+            return LiftingReturnInfo(valueToLift: .i32)
        case .swiftStruct:
            switch context {
            case .importTS:

diff --git a/Plugins/BridgeJS/Sources/BridgeJSLink/JSGlueGen.swift b/Plugins/BridgeJS/Sources/BridgeJSLink/JSGlueGen.swift
@@ -1422,27 +1422,19 @@ struct IntrinsicJSFragment: Sendable {
            return try .optionalLiftParameter(wrappedType: wrappedType, kind: kind, context: context)
        case .rawValueEnum(_, .string): return .stringLiftParameter
        case .associatedValueEnum(let fullName):
-            switch context {
-            case .importTS:
-                throw BridgeJSLinkError(
-                    message:
-                        "Associated value enums are not supported to be passed as parameters to imported JS functions: \(fullName)"
-                )
-            case .exportSwift:
-                let base = fullName.components(separatedBy: ".").last ?? fullName
-                return IntrinsicJSFragment(
-                    parameters: ["caseId"],
-                    printCode: { arguments, context in
-                        let (scope, printer) = (context.scope, context.printer)
-                        let caseId = arguments[0]
-                        let resultVar = scope.variable("enumValue")
-                        printer.write(
-                            "const \(resultVar) = \(JSGlueVariableScope.reservedEnumHelpers).\(base).lift(\(caseId));"
-                        )
-                        return [resultVar]
-                    }
-                )
-            }
+            let base = fullName.components(separatedBy: ".").last ?? fullName
+            return IntrinsicJSFragment(
+                parameters: ["caseId"],
+                printCode: { arguments, context in
+                    let (scope, printer) = (context.scope, context.printer)
+                    let caseId = arguments[0]
+                    let resultVar = scope.variable("enumValue")
+                    printer.write(
+                        "const \(resultVar) = \(JSGlueVariableScope.reservedEnumHelpers).\(base).lift(\(caseId));"
+                    )
+                    return [resultVar]
+                }
+            )
        case .swiftStruct(let fullName):
            switch context {
            case .importTS:
@@ -1502,15 +1494,7 @@ struct IntrinsicJSFragment: Sendable {
            return try .optionalLowerReturn(wrappedType: wrappedType, kind: kind)
        case .rawValueEnum(_, .string): return .stringLowerReturn
        case .associatedValueEnum(let fullName):
-            switch context {
-            case .importTS:
-                throw BridgeJSLinkError(
-                    message:
-                        "Associated value enums are not supported to be returned from imported JS functions: \(fullName)"
-                )
-            case .exportSwift:
-                return associatedValueLowerReturn(fullName: fullName)
-            }
+            return associatedValueLowerReturn(fullName: fullName)
        case .swiftStruct(let fullName):
            switch context {
            case .importTS:

diff --git a/Plugins/BridgeJS/Sources/BridgeJSSkeleton/BridgeJSSkeleton.swift b/Plugins/BridgeJS/Sources/BridgeJSSkeleton/BridgeJSSkeleton.swift
@@ -1611,10 +1611,10 @@ extension BridgeType {
    /// Whether a value of this type can be passed to a generated `Promise_resolve_<mangled>`
    /// settlement helper, i.e. lowered through the imported-parameter ABI. Every `async`
    /// exported return settles through `_bjs_makePromise`; the few types that cannot be lowered
-    /// (associated-value enums, protocols, namespace enums, and their compositions) are diagnosed.
+    /// (protocols, namespace enums, and their compositions) are diagnosed.
    public var isAsyncResolvable: Bool {
        switch self {
-        case .associatedValueEnum, .swiftProtocol, .namespaceEnum:
+        case .swiftProtocol, .namespaceEnum:
            return false
        case .nullable(let wrapped, _):
            return wrapped.isAsyncResolvable

diff --git a/Plugins/BridgeJS/Tests/BridgeJSToolTests/DiagnosticsTests.swift b/Plugins/BridgeJS/Tests/BridgeJSToolTests/DiagnosticsTests.swift
@@ -309,15 +309,14 @@ import Testing

    @Test
    func asyncReturnOfUnsupportedTypeIsDiagnosed() throws {
-        // An associated-value enum can be neither lowered through the imported-parameter ABI
-        // nor settled via `_bjs_makePromise`, so an async return of one must be diagnosed.
+        // Protocol existentials still can't be lowered through the imported-parameter ABI, so
+        // an async return of one must still be diagnosed.
        let source = """
-            @JS enum Payload {
-                case text(String)
-                case number(Int)
+            @JS protocol PayloadDelegate {
+                func notify()
            }
-            @JS func loadPayload() async -> Payload {
-                .number(1)
+            @JS func loadPayload() async -> PayloadDelegate {
+                fatalError()
            }
            """
        let swiftAPI = SwiftToSkeleton(

diff --git a/Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/MacroSwift/AsyncAssociatedValueEnum.swift b/Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/MacroSwift/AsyncAssociatedValueEnum.swift
@@ -0,0 +1,13 @@
+@JS enum AsyncPayloadResult {
+    case success(String)
+    case failure(Int)
+    case idle
+}
+
+@JS func asyncRoundTripAssociatedValueEnum(_ value: AsyncPayloadResult) async -> AsyncPayloadResult {
+    return value
+}
+
+@JS func asyncRoundTripOptionalAssociatedValueEnum(_ value: AsyncPayloadResult?) async -> AsyncPayloadResult? {
+    return value
+}
diff --git a/Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/MacroSwift/EnumAssociatedValueImport.swift b/Plugins/BridgeJS/Tests/BridgeJSToolTests/Inputs/MacroSwift/EnumAssociatedValueImport.swift
@@ -0,0 +1,14 @@
+@JS enum PayloadSignal {
+    case start(String)
+    case stop(Int)
+    case idle
+}
+
+// Associated-value enums bridge as their `Int32` case ID plus stack payload in imported
+// function parameters and return values.
+@JSClass struct PayloadSignalControls {
+    @JSFunction func send(_ signal: PayloadSignal) throws(JSException)
+    @JSFunction func current() throws(JSException) -> PayloadSignal
+    @JSFunction static func roundTrip(_ signal: PayloadSignal) throws(JSException) -> PayloadSignal
+    @JSFunction func roundTripOptional(_ signal: PayloadSignal?) throws(JSException) -> PayloadSignal?
+}
diff --git a/.../Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/AsyncAssociatedValueEnum.json b/.../Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/AsyncAssociatedValueEnum.json
@@ -0,0 +1,129 @@
+{
+  "exported" : {
+    "classes" : [
+
+    ],
+    "enums" : [
+      {
+        "cases" : [
+          {
+            "associatedValues" : [
+              {
+                "type" : {
+                  "string" : {
+
+                  }
+                }
+              }
+            ],
+            "name" : "success"
+          },
+          {
+            "associatedValues" : [
+              {
+                "type" : {
+                  "integer" : {
+                    "_0" : {
+                      "isSigned" : true,
+                      "width" : "word"
+                    }
+                  }
+                }
+              }
+            ],
+            "name" : "failure"
+          },
+          {
+            "associatedValues" : [
+
+            ],
+            "name" : "idle"
+          }
+        ],
+        "emitStyle" : "const",
+        "name" : "AsyncPayloadResult",
+        "staticMethods" : [
+
+        ],
+        "staticProperties" : [
+
+        ],
+        "swiftCallName" : "AsyncPayloadResult",
+        "tsFullPath" : "AsyncPayloadResult"
+      }
+    ],
+    "exposeToGlobal" : false,
+    "functions" : [
+      {
+        "abiName" : "bjs_asyncRoundTripAssociatedValueEnum",
+        "effects" : {
+          "isAsync" : true,
+          "isStatic" : false,
+          "isThrows" : false
+        },
+        "name" : "asyncRoundTripAssociatedValueEnum",
+        "parameters" : [
+          {
+            "label" : "_",
+            "name" : "value",
+            "type" : {
+              "associatedValueEnum" : {
+                "_0" : "AsyncPayloadResult"
+              }
+            }
+          }
+        ],
+        "returnType" : {
+          "associatedValueEnum" : {
+            "_0" : "AsyncPayloadResult"
+          }
+        }
+      },
+      {
+        "abiName" : "bjs_asyncRoundTripOptionalAssociatedValueEnum",
+        "effects" : {
+          "isAsync" : true,
+          "isStatic" : false,
+          "isThrows" : false
+        },
+        "name" : "asyncRoundTripOptionalAssociatedValueEnum",
+        "parameters" : [
+          {
+            "label" : "_",
+            "name" : "value",
+            "type" : {
+              "nullable" : {
+                "_0" : {
+                  "associatedValueEnum" : {
+                    "_0" : "AsyncPayloadResult"
+                  }
+                },
+                "_1" : "null"
+              }
+            }
+          }
+        ],
+        "returnType" : {
+          "nullable" : {
+            "_0" : {
+              "associatedValueEnum" : {
+                "_0" : "AsyncPayloadResult"
+              }
+            },
+            "_1" : "null"
+          }
+        }
+      }
+    ],
+    "protocols" : [
+
+    ],
+    "structs" : [
+
+    ]
+  },
+  "moduleName" : "TestModule",
+  "usedExternalModules" : [
+
+  ]
+}
diff --git a/...Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/AsyncAssociatedValueEnum.swift b/...Tests/BridgeJSToolTests/__Snapshots__/BridgeJSCodegenTests/AsyncAssociatedValueEnum.swift
@@ -0,0 +1,116 @@
+extension AsyncPayloadResult: _BridgedSwiftAssociatedValueEnum {
+    @_spi(BridgeJS) @_transparent public static func bridgeJSStackPopPayload(_ caseId: Int32) -> AsyncPayloadResult {
+        switch caseId {
+        case 0:
+            return .success(String.bridgeJSStackPop())
+        case 1:
+            return .failure(Int.bridgeJSStackPop())
+        case 2:
+            return .idle
+        default:
+            fatalError("Unknown AsyncPayloadResult case ID: \(caseId)")
+        }
+    }
+
+    @_spi(BridgeJS) @_transparent public consuming func bridgeJSStackPushPayload() -> Int32 {
+        switch self {
+        case .success(let param0):
+            param0.bridgeJSStackPush()
+            return Int32(0)
+        case .failure(let param0):
+            param0.bridgeJSStackPush()
+            return Int32(1)
+        case .idle:
+            return Int32(2)
+        }
+    }
+}
+
+@_expose(wasm, "bjs_asyncRoundTripAssociatedValueEnum")
+@_cdecl("bjs_asyncRoundTripAssociatedValueEnum")
+public func _bjs_asyncRoundTripAssociatedValueEnum(_ value: Int32) -> Int32 {
+    #if arch(wasm32)
+    let _tmp_value = AsyncPayloadResult.bridgeJSLiftParameter(value)
+    return _bjs_makePromise(resolve: Promise_resolve_18AsyncPayloadResultO, reject: Promise_reject) {
+        return await asyncRoundTripAssociatedValueEnum(_: _tmp_value)
+    }
+    #else
+    fatalError("Only available on WebAssembly")
+    #endif
+}
+
+@_expose(wasm, "bjs_asyncRoundTripOptionalAssociatedValueEnum")
+@_cdecl("bjs_asyncRoundTripOptionalAssociatedValueEnum")
+public func _bjs_asyncRoundTripOptionalAssociatedValueEnum(_ valueIsSome: Int32, _ valueCaseId: Int32) -> Int32 {
+    #if arch(wasm32)
+    let _tmp_value = Optional<AsyncPayloadResult>.bridgeJSLiftParameter(valueIsSome, valueCaseId)
+    return _bjs_makePromise(resolve: Promise_resolve_Sq18AsyncPayloadResultO, reject: Promise_reject) {
+        return await asyncRoundTripOptionalAssociatedValueEnum(_: _tmp_value)
+    }
+    #else
+    fatalError("Only available on WebAssembly")
+    #endif
+}
+
+@JSFunction func Promise_reject(_ promise: JSObject, _ value: JSValue) throws(JSException)
+
+#if arch(wasm32)
+@_extern(wasm, module: "bjs", name: "promise_reject_TestModule")
+fileprivate func promise_reject_TestModule_extern(_ promise: Int32, _ valueKind: Int32, _ valuePayload1: Int32, _ valuePayload2: Float64) -> Void
+#else
+fileprivate func promise_reject_TestModule_extern(_ promise: Int32, _ valueKind: Int32, _ valuePayload1: Int32, _ valuePayload2: Float64) -> Void {
+    fatalError("Only available on WebAssembly")
+}
+#endif
+@inline(never) fileprivate func promise_reject_TestModule(_ promise: Int32, _ valueKind: Int32, _ valuePayload1: Int32, _ valuePayload2: Float64) -> Void {
+    return promise_reject_TestModule_extern(promise, valueKind, valuePayload1, valuePayload2)
+}
+
+func _$Promise_reject(_ promise: JSObject, _ value: JSValue) throws(JSException) -> Void {
+    let promiseValue = promise.bridgeJSLowerParameter()
+    let (valueKind, valuePayload1, valuePayload2) = value.bridgeJSLowerParameter()
+    promise_reject_TestModule(promiseValue, valueKind, valuePayload1, valuePayload2)
+    if let error = _swift_js_take_exception() { throw error }
+}
+
+@JSFunction func Promise_resolve_18AsyncPayloadResultO(_ promise: JSObject, _ value: AsyncPayloadResult) throws(JSException)
+
+#if arch(wasm32)
+@_extern(wasm, module: "bjs", name: "promise_resolve_TestModule_18AsyncPayloadResultO")
+fileprivate func promise_resolve_TestModule_18AsyncPayloadResultO_extern(_ promise: Int32, _ value: Int32) -> Void
+#else
+fileprivate func promise_resolve_TestModule_18AsyncPayloadResultO_extern(_ promise: Int32, _ value: Int32) -> Void {
+    fatalError("Only available on WebAssembly")
+}
+#endif
+@inline(never) fileprivate func promise_resolve_TestModule_18AsyncPayloadResultO(_ promise: Int32, _ value: Int32) -> Void {
+    return promise_resolve_TestModule_18AsyncPayloadResultO_extern(promise, value)
+}
+
+func _$Promise_resolve_18AsyncPayloadResultO(_ promise: JSObject, _ value: AsyncPayloadResult) throws(JSException) -> Void {
+    let promiseValue = promise.bridgeJSLowerParameter()
+    let valueCaseId = value.bridgeJSLowerParameter()
+    promise_resolve_TestModule_18AsyncPayloadResultO(promiseValue, valueCaseId)
+    if let error = _swift_js_take_exception() { throw error }
+}
+
+@JSFunction func Promise_resolve_Sq18AsyncPayloadResultO(_ promise: JSObject, _ value: Optional<AsyncPayloadResult>) throws(JSException)
+
+#if arch(wasm32)
+@_extern(wasm, module: "bjs", name: "promise_resolve_TestModule_Sq18AsyncPayloadResultO")
+fileprivate func promise_resolve_TestModule_Sq18AsyncPayloadResultO_extern(_ promise: Int32, _ valueIsSome: Int32, _ valueCaseId: Int32) -> Void
+#else
+fileprivate func promise_resolve_TestModule_Sq18AsyncPayloadResultO_extern(_ promise: Int32, _ valueIsSome: Int32, _ valueCaseId: Int32) -> Void {
+    fatalError("Only available on WebAssembly")
+}
+#endif
+@inline(never) fileprivate func promise_resolve_TestModule_Sq18AsyncPayloadResultO(_ promise: Int32, _ valueIsSome: Int32, _ valueCaseId: Int32) -> Void {
+    return promise_resolve_TestModule_Sq18AsyncPayloadResultO_extern(promise, valueIsSome, valueCaseId)
+}
+
+func _$Promise_resolve_Sq18AsyncPayloadResultO(_ promise: JSObject, _ value: Optional<AsyncPayloadResult>) throws(JSException) -> Void {
+    let promiseValue = promise.bridgeJSLowerParameter()
+    let (valueIsSome, valueCaseId) = value.bridgeJSLowerParameter()
+    promise_resolve_TestModule_Sq18AsyncPayloadResultO(promiseValue, valueIsSome, valueCaseId)
+    if let error = _swift_js_take_exception() { throw error }
+}