[tryout fix] concurrency bug in NamespacedHierarchicalStore#computeIfAbsent(Object, Object, Function) #5171 #5209

Signed-off-by: Vincent Potucek <vpotucek@me.com>

Author: Vincent Potucek

junit-platform-engine/src/main/java/org/junit/platform/engine/support/store/NamespacedHierarchicalStore.java

@@ -236,7 +236,6 @@ public void close() {
 	 * closed
 	 * @since 6.0
 	 */
-	@SuppressWarnings("ReferenceEquality")
 	@API(status = MAINTAINED, since = "6.0")
 	public <K, V> Object computeIfAbsent(N namespace, K key, Function<? super K, ? extends V> defaultCreator) {
 		requireNonNull(defaultCreator);
@@ -245,7 +244,7 @@ public <K, V> Object computeIfAbsent(N namespace, K key, Function<? super K, ? e
 		var result = StoredValue.evaluateIfNotNull(storedValue);
 		if (result == null) {
 			var newStoredValue = storedValues.compute(compositeKey, (__, oldStoredValue) -> {
-				if (oldStoredValue == storedValue || oldStoredValue == null) {
+				if (oldStoredValue == null || oldStoredValue.equals(storedValue)) {
 					rejectIfClosed();
 					return newStoredValue(new MemoizingSupplier(() -> {
 						rejectIfClosed();
@@ -258,7 +257,7 @@ public <K, V> Object computeIfAbsent(N namespace, K key, Function<? super K, ? e
 				return requireNonNull(newStoredValue.evaluate());
 			}
 			catch (Throwable t) { // remove failed entry to allow retry.
-				if (newStoredValue == storedValues.get(compositeKey)) {
+				if (newStoredValue.equals(storedValues.get(compositeKey))) {
 					storedValues.remove(compositeKey, newStoredValue);
 				}
 				throw t;