[JExtract/JNI] Import enums

Samples/JExtractJNISampleApp/Sources/MySwiftLibrary/Alignment.swift

@@ -0,0 +1,18 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+public enum Alignment: String {
+  case horizontal
+  case vertical
+}

Samples/JExtractJNISampleApp/Sources/MySwiftLibrary/Vehicle.swift

@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+public enum Vehicle {
+  case bicycle
+  case car(String)
+  case motorbike(String, horsePower: Int64)
+
+  public init?(name: String) {
+    switch name {
+      case "bicycle": self = .bicycle
+      case "car": self = .car("Unknown")
+      case "motorbike": self = .motorbike("Unknown", horsePower: 0)
+      default: return nil
+    }
+  }
+
+  public var name: String {
+    switch self {
+    case .bicycle: "bicycle"
+    case .car: "car"
+    case .motorbike: "motorbike"
+    }
+  }
+
+  public func isFasterThan(other: Vehicle) -> Bool {
+    switch (self, other) {
+      case (.bicycle, .bicycle), (.bicycle, .car), (.bicycle, .motorbike): false
+      case (.car, .bicycle): true
+      case (.car, .motorbike), (.car, .car): false
+      case (.motorbike, .bicycle), (.motorbike, .car): true
+      case (.motorbike, .motorbike): false
+    }
+  }
+
+  public mutating func upgrade() {
+    switch self {
+      case .bicycle: self = .car("Unknown")
+      case .car: self = .motorbike("Unknown", horsePower: 0)
+      case .motorbike: break
+    }
+  }
+}

Samples/JExtractJNISampleApp/Sources/MySwiftLibrary/swift-java.config

@@ -1,4 +1,5 @@
 {
   "javaPackage": "com.example.swift",
   "mode": "jni",
+  "logLevel": ["debug"]
 }

Samples/JExtractJNISampleApp/src/jmh/java/com/example/swift/EnumBenchmark.java

@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 20245Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package com.example.swift;
+
+import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.infra.Blackhole;
+import org.swift.swiftkit.core.ClosableSwiftArena;
+import org.swift.swiftkit.core.ConfinedSwiftMemorySession;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@Warmup(iterations = 5, time = 200, timeUnit = TimeUnit.MILLISECONDS)
+@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@Fork(value = 3, jvmArgsAppend = { "--enable-native-access=ALL-UNNAMED" })
+public class EnumBenchmark {
+
+    @State(Scope.Benchmark)
+    public static class BenchmarkState {
+        ClosableSwiftArena arena;
+        Vehicle vehicle;
+
+        @Setup(Level.Trial)
+        public void beforeAll() {
+            arena = new ConfinedSwiftMemorySession();
+            vehicle = Vehicle.motorbike("Yamaha", 900, arena);
+        }
+
+        @TearDown(Level.Trial)
+        public void afterAll() {
+            arena.close();
+        }
+    }
+
+    @Benchmark
+    public Vehicle.Motorbike java_copy(BenchmarkState state, Blackhole bh) {
+        Vehicle.Motorbike motorbike = state.vehicle.getAsMotorbike().orElseThrow();
+        bh.consume(motorbike.arg0());
+        bh.consume(motorbike.horsePower());
+
+        return motorbike;
+    }
+}

Samples/JExtractJNISampleApp/src/test/java/com/example/swift/AlignmentEnumTest.java

@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package com.example.swift;
+
+import org.junit.jupiter.api.Test;
+import org.swift.swiftkit.core.ConfinedSwiftMemorySession;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class AlignmentEnumTest {
+    @Test
+    void rawValue() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Optional<Alignment> invalid = Alignment.init("invalid", arena);
+            assertFalse(invalid.isPresent());
+
+            Optional<Alignment> horizontal = Alignment.init("horizontal", arena);
+            assertTrue(horizontal.isPresent());
+            assertEquals("horizontal", horizontal.get().getRawValue());
+
+            Optional<Alignment> vertical = Alignment.init("vertical", arena);
+            assertTrue(vertical.isPresent());
+            assertEquals("vertical", vertical.get().getRawValue());
+        }
+    }
+}

Samples/JExtractJNISampleApp/src/test/java/com/example/swift/VehicleEnumTest.java

@@ -0,0 +1,130 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package com.example.swift;
+
+import org.junit.jupiter.api.Test;
+import org.swift.swiftkit.core.ConfinedSwiftMemorySession;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class VehicleEnumTest {
+    @Test
+    void bicycle() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.bicycle(arena);
+            assertNotNull(vehicle);
+        }
+    }
+
+    @Test
+    void car() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.car("Porsche 911", arena);
+            assertNotNull(vehicle);
+        }
+    }
+
+    @Test
+    void motorbike() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.motorbike("Yamaha", 750, arena);
+            assertNotNull(vehicle);
+        }
+    }
+
+    @Test
+    void initName() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            assertFalse(Vehicle.init("bus", arena).isPresent());
+            Optional<Vehicle> vehicle = Vehicle.init("car", arena);
+            assertTrue(vehicle.isPresent());
+            assertNotNull(vehicle.get());
+        }
+    }
+
+    @Test
+    void nameProperty() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.bicycle(arena);
+            assertEquals("bicycle", vehicle.getName());
+        }
+    }
+
+    @Test
+    void isFasterThan() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle bicycle = Vehicle.bicycle(arena);
+            Vehicle car = Vehicle.car("Porsche 911", arena);
+            assertFalse(bicycle.isFasterThan(car));
+            assertTrue(car.isFasterThan(bicycle));
+        }
+    }
+
+    @Test
+    void upgrade() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.bicycle(arena);
+            assertEquals("bicycle", vehicle.getName());
+            vehicle.upgrade();
+            assertEquals("car", vehicle.getName());
+            vehicle.upgrade();
+            assertEquals("motorbike", vehicle.getName());
+        }
+    }
+
+    @Test
+    void getAsBicycle() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.bicycle(arena);
+            Vehicle.Bicycle bicycle = vehicle.getAsBicycle().orElseThrow();
+            assertNotNull(bicycle);
+        }
+    }
+
+    @Test
+    void getAsCar() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.car("BMW", arena);
+            Vehicle.Car car = vehicle.getAsCar().orElseThrow();
+            assertEquals("BMW", car.arg0());
+        }
+    }
+
+    @Test
+    void getAsMotorbike() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.motorbike("Yamaha", 750, arena);
+            Vehicle.Motorbike motorbike = vehicle.getAsMotorbike().orElseThrow();
+            assertEquals("Yamaha", motorbike.arg0());
+            assertEquals(750, motorbike.horsePower());
+        }
+    }
+
+    @Test
+    void associatedValuesAreCopied() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            Vehicle vehicle = Vehicle.car("BMW", arena);
+            Vehicle.Car car = vehicle.getAsCar().orElseThrow();
+            assertEquals("BMW", car.arg0());
+            vehicle.upgrade();
+            Vehicle.Motorbike motorbike = vehicle.getAsMotorbike().orElseThrow();
+            assertNotNull(motorbike);
+            // Motorbike should still remain
+            assertEquals("BMW", car.arg0());
+        }
+    }
+}

Sources/JExtractSwiftLib/Convenience/SwiftSyntax+Extensions.swift

@@ -253,6 +253,8 @@ extension DeclSyntaxProtocol {
           }
         ))
         .triviaSanitizedDescription
+    case .enumCaseDecl(let node):
+      node.triviaSanitizedDescription
     default:
       fatalError("unimplemented \(self.kind)")
     }

Sources/JExtractSwiftLib/FFM/CDeclLowering/FFMSwift2JavaGenerator+FunctionLowering.swift

@@ -835,6 +835,10 @@ extension LoweredFunctionSignature {
     case .setter:
       assert(paramExprs.count == 1)
       resultExpr = "\(callee) = \(paramExprs[0])"
+
+    case .enumCase:
+      // This should not be called, but let's fatalError.
+      fatalError("Enum cases are not supported with FFM.")
     }
 
     // Lower the result.

Sources/JExtractSwiftLib/FFM/FFMSwift2JavaGenerator+JavaTranslation.swift

@@ -146,7 +146,7 @@ extension FFMSwift2JavaGenerator {
       let javaName = switch decl.apiKind {
       case .getter: decl.javaGetterName
       case .setter: decl.javaSetterName
-      case .function, .initializer: decl.name
+      case .function, .initializer, .enumCase: decl.name
       }
 
       // Signature.