[JExtract/JNI] Add tests for structs

Samples/JExtractJNISampleApp/Sources/MySwiftLibrary/MySwiftStruct.swift

@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+public struct MySwiftStruct {
+  private var cap: Int64
+  public var len: Int64
+
+  public init(cap: Int64, len: Int64) {
+    self.cap = cap
+    self.len = len
+  }
+
+  public func getCapacity() -> Int64 {
+    self.cap
+  }
+
+  public mutating func increaseCap(by value: Int64) -> Int64 {
+    precondition(value > 0)
+    self.cap += value
+    return self.cap
+  }
+}

Samples/JExtractJNISampleApp/src/main/java/com/example/swift/HelloJava2SwiftJNI.java

@@ -52,6 +52,12 @@ static void examples() {
             } catch (Exception e) {
                 System.out.println("Caught exception: " + e.getMessage());
             }
+
+            MySwiftStruct myStruct = MySwiftStruct.init(12, 34, arena);
+            System.out.println("myStruct.cap: " + myStruct.getCapacity());
+            System.out.println("myStruct.len: " + myStruct.getLen());
+            myStruct.increaseCap(10);
+            System.out.println("myStruct.cap after increase: " + myStruct.getCapacity());
         }
 
         System.out.println("DONE.");

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

@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 static org.junit.jupiter.api.Assertions.*;
+
+public class MySwiftStructTest {
+    @Test
+    void init() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            MySwiftStruct s = MySwiftStruct.init(1337, 42, arena);
+            assertEquals(1337, s.getCapacity());
+            assertEquals(42, s.getLen());
+        }
+    }
+
+    @Test
+    void getAndSetLen() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            MySwiftStruct s = MySwiftStruct.init(1337, 42, arena);
+            s.setLen(100);
+            assertEquals(100, s.getLen());
+        }
+    }
+
+    @Test
+    void increaseCap() {
+        try (var arena = new ConfinedSwiftMemorySession()) {
+            MySwiftStruct s = MySwiftStruct.init(1337, 42, arena);
+            long newCap = s.increaseCap(10);
+            assertEquals(1347, newCap);
+            assertEquals(1347, s.getCapacity());
+        }
+    }
+}

Tests/JExtractSwiftTests/JNI/JNIStructTests.swift

@@ -0,0 +1,188 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+import JExtractSwiftLib
+import Testing
+
+@Suite
+struct JNIStructTests {
+  let source = """
+    public struct MyStruct {
+      let x: Int64
+      let y: Int64
+
+      public init(x: Int64, y: Int64) {
+        self.x = y
+        self.y = y
+      }
+
+      public func doSomething(x: Int64) {}
+    }
+  """
+
+  @Test
+  func generatesJavaClass() throws {
+    try assertOutput(input: source, .jni, .java, expectedChunks: [
+      """
+      // Generated by jextract-swift
+      // Swift module: SwiftModule
+
+      package com.example.swift;
+
+      import org.swift.swiftkit.core.*;
+      import org.swift.swiftkit.core.util.*;
+
+      public final class MyStruct extends JNISwiftInstance {
+        static final String LIB_NAME = "SwiftModule";
+
+        @SuppressWarnings("unused")
+        private static final boolean INITIALIZED_LIBS = initializeLibs();
+        static boolean initializeLibs() {
+          System.loadLibrary(LIB_NAME);
+          return true;
+        }
+
+        public MyStruct(long selfPointer, SwiftArena swiftArena) {
+          super(selfPointer, swiftArena);
+        }
+      """,
+      """
+      private static native void $destroy(long selfPointer);
+      """,
+      """
+      @Override
+      protected Runnable $createDestroyFunction() {
+        long $selfPointer = this.pointer(); 
+        return new Runnable() {
+          @Override
+          public void run() {
+            MyStruct.$destroy($selfPointer);
+          }
+        };
+      }
+      """
+    ])
+  }
+
+  @Test
+  func initializer_javaBindings() throws {
+    try assertOutput(
+      input: source,
+      .jni,
+      .java,
+      expectedChunks: [
+        """
+        /**
+          * Downcall to Swift:
+          * {@snippet lang=swift :
+          * public init(x: Int64, y: Int64)
+          * }
+          */
+        public static MyStruct init(long x, long y, SwiftArena swiftArena$) {
+          long selfPointer = MyStruct.allocatingInit(x, y);
+          return new MyStruct(selfPointer, swiftArena$);
+        }
+        """,
+        """
+        private static native long allocatingInit(long x, long y);
+        """,
+      ]
+    )
+  }
+
+  @Test
+  func initializer_swiftThunks() throws {
+    try assertOutput(
+      input: source,
+      .jni,
+      .swift,
+      detectChunkByInitialLines: 1,
+      expectedChunks: [
+        """
+        @_cdecl("Java_com_example_swift_MyStruct_allocatingInit__JJ")
+        func Java_com_example_swift_MyStruct_allocatingInit__JJ(environment: UnsafeMutablePointer<JNIEnv?>!, thisClass: jclass, x: jlong, y: jlong) -> jlong {
+          let selfPointer = UnsafeMutablePointer<MyStruct>.allocate(capacity: 1)
+          selfPointer.initialize(to: MyStruct(x: Int64(fromJNI: x, in: environment!), y: Int64(fromJNI: y, in: environment!)))
+          return Int64(Int(bitPattern: selfPointer)).getJNIValue(in: environment)
+        }
+        """
+      ]
+    )
+  }
+
+  @Test
+  func destroyFunction_swiftThunks() throws {
+    try assertOutput(
+      input: source,
+      .jni,
+      .swift,
+      detectChunkByInitialLines: 1,
+      expectedChunks: [
+        """
+        @_cdecl("Java_com_example_swift_MyStruct__00024destroy__J")
+        func Java_com_example_swift_MyStruct__00024destroy__J(environment: UnsafeMutablePointer<JNIEnv?>!, thisClass: jclass, selfPointer: jlong) {
+          let pointer = UnsafeMutablePointer<MyStruct>(bitPattern: Int(Int64(fromJNI: selfPointer, in: environment!)))!
+          pointer.deinitialize(count: 1)
+          pointer.deallocate()
+        }
+        """
+      ]
+    )
+  }
+
+  @Test
+  func memberMethod_javaBindings() throws {
+    try assertOutput(
+      input: source,
+      .jni,
+      .java,
+      expectedChunks: [
+        """
+        /**
+          * Downcall to Swift:
+          * {@snippet lang=swift :
+          * public func doSomething(x: Int64)
+          * }
+          */
+        public void doSomething(long x) {
+          long selfPointer = this.pointer();
+          MyStruct.$doSomething(x, selfPointer);
+        }
+        """,
+        """
+        private static native void $doSomething(long x, long selfPointer);
+        """
+      ]
+    )
+  }
+
+  @Test
+  func memberMethod_swiftThunks() throws {
+    try assertOutput(
+      input: source,
+      .jni,
+      .swift,
+      detectChunkByInitialLines: 1,
+      expectedChunks: [
+        """
+        @_cdecl("Java_com_example_swift_MyStruct__00024doSomething__JJ")
+        func Java_com_example_swift_MyStruct__00024doSomething__JJ(environment: UnsafeMutablePointer<JNIEnv?>!, thisClass: jclass, x: jlong, selfPointer: jlong) {
+          let self$ = UnsafeMutablePointer<MyStruct>(bitPattern: Int(Int64(fromJNI: selfPointer, in: environment!)))!
+          self$.pointee.doSomething(x: Int64(fromJNI: x, in: environment!))
+        }
+        """,
+      ]
+    )
+  }
+}