Required properties: Break binding to model on write

This mirrors the behavior in other parts of QML where writing to a
property in imperative code breaks the binding.

Change-Id: Id19eef17a3c5e77bc4c2772bd749b38c732606a8
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

2 files changed, 71 insertions, 0 deletions

diff --git a/tests/auto/quick/qquickpathview/data/delegateWithRequiredProperties.3.qml b/tests/auto/quick/qquickpathview/data/delegateWithRequiredProperties.3.qml
new file mode 100644
index 0000000000..2996ba18fd
--- /dev/null
+++ b/tests/auto/quick/qquickpathview/data/delegateWithRequiredProperties.3.qml
@@ -0,0 +1,64 @@
+import QtQuick 2.14
+
+Item {
+    id: root
+    width: 800
+    height: 600
+    property bool working: false
+
+    ListModel {
+        id: myModel
+        ListElement {
+            name: "Bill Jones"
+            place: "Berlin"
+        }
+        ListElement {
+            name: "Jane Doe"
+            place: "Oslo"
+        }
+        ListElement {
+            name: "John Smith"
+            place: "Oulo"
+        }
+    }
+
+    Component {
+        id: delegateComponent
+        Rectangle {
+            id: myDelegate
+            height: 50
+            width: 50
+        required property string name
+        required property int index
+        onNameChanged: () => {if (myDelegate.name === "You-know-who") root.working = false}
+            Text {
+                text: myDelegate.name
+                font.pointSize: 10
+                anchors.fill: myDelegate
+            }
+    Component.onCompleted: () => {myDelegate.name = "break binding"}
+        }
+    }
+
+    PathView {
+        anchors.fill: parent
+        model: myModel
+        delegate: delegateComponent
+        path: Path {
+            startX: 80; startY: 100
+            PathQuad { x: 120; y: 25; controlX: 260; controlY: 75 }
+            PathQuad { x: 140; y: 100; controlX: -20; controlY: 75 }
+        }
+    }
+    Timer {
+        interval: 1
+        running: true
+        repeat: false
+        onTriggered: () => {
+            myModel.setProperty(1, "name", "You-know-who")
+            myModel.setProperty(2, "name", "You-know-who")
+            root.working = true
+        }
+    }
+
+}
diff --git a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
index 36a242bf3b..d2058cc8b3 100644
--- a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
+++ b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
@@ -2676,6 +2676,13 @@ void tst_QQuickPathView::requiredPropertiesInDelegate()
         window->show();
         QTRY_VERIFY(window->rootObject()->property("working").toBool());
     }
+    {
+        QScopedPointer<QQuickView> window(createView());
+        QTest::ignoreMessage(QtMsgType::QtWarningMsg, QRegularExpression("Writing to \"name\" broke the binding to the underlying model"));
+        window->setSource(testFileUrl("delegateWithRequiredProperties.3.qml"));
+        window->show();
+        QTRY_VERIFY(window->rootObject()->property("working").toBool());
+    }
 }
 
 void tst_QQuickPathView::requiredPropertiesInDelegatePreventUnrelated()