QtQml: Recognize JavaScript null as equivalent to nullptr QObject*

Otherwise we can go into infinite recursion there.

Pick-to: 6.2 6.4
Fixes: QTBUG-108651
Change-Id: I73a7c524b28d0eacb151f2090e3dce6afbc029d1
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 28 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmllanguage/data/nullIsNull.qml b/tests/auto/qml/qqmllanguage/data/nullIsNull.qml
new file mode 100644
index 0000000000..a6cbbee0bf
--- /dev/null
+++ b/tests/auto/qml/qqmllanguage/data/nullIsNull.qml
@@ -0,0 +1,28 @@
+import QtQml
+
+QtObject {
+    id: root
+    property alias someProperty: internal.someProperty
+
+    property Timer t: Timer {
+        interval: 1
+        running: true
+        onTriggered: root.someProperty = null
+    }
+
+    property QtObject a: QtObject {
+        id: someObjectInstance
+    }
+
+    property QtObject b: QtObject {
+        id: internal
+        property QtObject someProperty: someObjectInstance ? someObjectInstance : null
+    }
+
+    property Connections c: Connections {
+        target: internal
+        function onSomePropertyChanged() {
+              internal.someProperty = null
+        }
+    }
+}