QML list property: Avoid crash if contained object is deleted

Task-number: QTBUG-81123
Change-Id: I3dd1a42e444f817722368cd268c2f987a99fbf1c
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 36 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmllanguage/data/listContainingDeleted.qml b/tests/auto/qml/qqmllanguage/data/listContainingDeleted.qml
new file mode 100644
index 0000000000..efd273ddc6
--- /dev/null
+++ b/tests/auto/qml/qqmllanguage/data/listContainingDeleted.qml
@@ -0,0 +1,36 @@
+import QtQuick 2.12
+
+Item {
+    width: 1024
+    height: 800
+
+    property Component a: Component {
+        id: a
+        Item {
+            property list<QtObject> myList: [
+                QtObject {
+                    property bool enabled: true
+                }
+            ]
+        }
+    }
+    Component {
+        id: b
+        Item {
+            property list<QtObject> myList
+
+            function test() {
+                for (var i = 0; i < myList.length; ++i)
+                    console.log(i, "==", myList[i].enabled)
+            }
+        }
+    }
+    property Item instance
+    function doAssign(o) {
+        instance = b.createObject(null, {myList: o.myList})
+    }
+    function use() {
+        instance.test()
+    }
+
+}