qqmllistmodel: Fix QObjects setting indestructible

It makes a QObject indestructable only if its ownership is determined.
This fixes an issue where a QObject created by createObject() in QML
becomes indestructable once it is appended to a ListModel.

Fixes: QTBUG-95895
Change-Id: I30647298977d7901dab938626e8f94b9910c21e3
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Jaeyoon Jung <jaeyoon.jung@lge.com>
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
(cherry picked from commit 69e07c55ad9b49b7643ffddfedc9a558983272ad)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

3 files changed, 54 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmllistmodel/data/destroyObject.qml b/tests/auto/qml/qqmllistmodel/data/destroyObject.qml
new file mode 100644
index 0000000000..e6b3f33bb9
--- /dev/null
+++ b/tests/auto/qml/qqmllistmodel/data/destroyObject.qml
@@ -0,0 +1,23 @@
+import QtQml
+
+QtObject {
+    id: root
+    property ListModel projects: ListModel {}
+    property var object
+
+    Component.onCompleted: {
+        var comp= Qt.createComponent("dummyItem.qml");
+        object = comp.createObject(root, {});
+        projects.append({"obj": object});
+    }
+
+    function destroy() {
+        try {
+            object.destroy();
+        } catch(e) {
+            console.warn(e);
+            return false;
+        }
+        return true;
+    }
+}
diff --git a/tests/auto/qml/qqmllistmodel/data/dummyItem.qml b/tests/auto/qml/qqmllistmodel/data/dummyItem.qml
new file mode 100644
index 0000000000..c9939efcdf
--- /dev/null
+++ b/tests/auto/qml/qqmllistmodel/data/dummyItem.qml
@@ -0,0 +1,5 @@
+import QtQml
+
+QtObject {
+    property var random: null
+}
diff --git a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
index a9b6ec03a4..7f94180274 100644
--- a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
+++ b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
@@ -136,6 +136,7 @@ private slots:
     void destroyObject();
     void emptyStringNotUndefined();
     void listElementWithTemplateString();
+    void destroyComponentObject();
 };
 
 bool tst_qqmllistmodel::compareVariantList(const QVariantList &testList, QVariant object)
@@ -1856,6 +1857,31 @@ void tst_qqmllistmodel::listElementWithTemplateString()
     QVERIFY(!root.isNull());
 }
 
+//QTBUG-95895
+void tst_qqmllistmodel::destroyComponentObject()
+{
+    QQmlEngine eng;
+    QQmlComponent component(&eng, testFileUrl("destroyObject.qml"));
+    QVERIFY(!component.isError());
+    QScopedPointer<QObject> obj(component.create());
+    QVERIFY(!obj.isNull());
+    QQmlListModel *list = qvariant_cast<QQmlListModel *>(obj->property("projects"));
+    QVERIFY(list != nullptr);
+    QCOMPARE(list->count(), 1);
+    QPointer<QObject> created(qvariant_cast<QObject *>(obj->property("object")));
+    QVERIFY(!created.isNull());
+    QCOMPARE(list->get(0).property("obj").toQObject(), created.data());
+    QVariant retVal;
+    QMetaObject::invokeMethod(obj.data(),
+                              "destroy",
+                               Qt::DirectConnection,
+                               Q_RETURN_ARG(QVariant, retVal));
+    QVERIFY(retVal.toBool());
+    QTRY_VERIFY(created.isNull());
+    QTRY_VERIFY(list->get(0).property("obj").isUndefined());
+    QCOMPARE(list->count(), 1);
+}
+
 QTEST_MAIN(tst_qqmllistmodel)
 
 #include "tst_qqmllistmodel.moc"