WIP

Author: rintaro

SwiftKit/src/main/java/org/swift/swiftkit/AutoSwiftMemorySession.java

@@ -60,6 +60,14 @@ public void register(SwiftInstance instance) {
         cleaner.register(instance, cleanupAction);
     }
 
+    // visible for testing
+    void register(SwiftInstance object, SwiftInstanceCleanup cleanupAction) {
+        Objects.requireNonNull(object, "obj");
+        Objects.requireNonNull(cleanupAction, "cleanupAction");
+
+        cleaner.register(object, cleanupAction);
+    }
+
     @Override
     public MemorySegment allocate(long byteSize, long byteAlignment) {
         return arena.allocate(byteSize, byteAlignment);

SwiftKit/src/main/java/org/swift/swiftkit/SwiftInstanceCleanup.java

@@ -27,9 +27,12 @@ record SwiftInstanceCleanup(
 
     @Override
     public void run() {
-        System.out.println("[debug] Destroy swift value [" + selfType.getSwiftName() + "]: " + selfPointer);
-
         markAsDestroyed.run();
-        SwiftValueWitnessTable.destroy(selfType, selfPointer);
+
+        // Allow null pointers just for AutoArena tests.
+        if (selfType != null && selfPointer != null) {
+            System.out.println("[debug] Destroy swift value [" + selfType.getSwiftName() + "]: " + selfPointer);
+            SwiftValueWitnessTable.destroy(selfType, selfPointer);
+        }
     }
 }

SwiftKit/src/test/java/org/swift/swiftkit/AutoArenaTest.java

@@ -26,49 +26,31 @@ public class AutoArenaTest {
     @Test
     @SuppressWarnings("removal") // System.runFinalization() will be removed
     public void cleaner_releases_native_resource() {
-        SwiftHeapObject object = new FakeSwiftHeapObject();
-
-        // Latch waiting for the cleanup of the object
-        var cleanupLatch = new CountDownLatch(1);
-
-        // we're retaining the `object`, register it with the arena:
-        AutoSwiftMemorySession arena = (AutoSwiftMemorySession) SwiftArena.ofAuto();
+        SwiftArena arena = SwiftArena.ofAuto();
 
+        // This object is registered to the arena.
+        var object = new FakeSwiftInstance(arena);
         var statusDestroyedFlag = object.$statusDestroyedFlag();
-        Runnable markAsDestroyed = () -> statusDestroyedFlag.set(true);
-
-        arena.register(object,
-                new SwiftHeapObjectCleanup(object.$memorySegment(), object.$swiftType(), markAsDestroyed) {
-                    @Override
-                    public void run() throws UnexpectedRetainCountException {
-                        cleanupLatch.countDown();
-                    }
-                });
 
         // Release the object and hope it gets GC-ed soon
 
         // noinspection UnusedAssignment
         object = null;
 
         var i = 1_000;
-        while (cleanupLatch.getCount() != 0) {
+        while (!statusDestroyedFlag.get()) {
             System.runFinalization();
             System.gc();
 
             if (i-- < 1) {
                 throw new RuntimeException("Reference was not cleaned up! Did Cleaner not pick up the release?");
             }
         }
-
     }
 
-    private static class FakeSwiftHeapObject implements SwiftHeapObject {
-        public FakeSwiftHeapObject() {
-        }
-
-        @Override
-        public MemorySegment $memorySegment() {
-            return MemorySegment.NULL;
+    private static class FakeSwiftInstance extends SwiftInstance implements SwiftHeapObject {
+        public FakeSwiftInstance(SwiftArena arena) {
+            super(MemorySegment.NULL, arena);
         }
 
         @Override
@@ -80,10 +62,5 @@ public FakeSwiftHeapObject() {
         public SwiftAnyType $swiftType() {
             return null;
         }
-
-        @Override
-        public AtomicBoolean $statusDestroyedFlag() {
-            return new AtomicBoolean();
-        }
     }
 }