Improve warning for QtQml.Binding

Print a warning if there is no property with the given
name of the specified target object, or the property
is read-only.

Change-Id: I5dc2e8330fb1ce53be396b7bf5baf13c1702d2f4
Task-number: QTBUG-39243
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

3 files changed, 58 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlbinding/data/readonlyProperty.qml b/tests/auto/qml/qqmlbinding/data/readonlyProperty.qml
new file mode 100644
index 0000000000..fa8d93d355
--- /dev/null
+++ b/tests/auto/qml/qqmlbinding/data/readonlyProperty.qml
@@ -0,0 +1,13 @@
+import QtQuick 2.0
+
+Item {
+    id: root
+
+    readonly property string name: "John"
+
+    Binding {
+        target: root
+        property: "name"
+        value: "Doe"
+    }
+}
diff --git a/tests/auto/qml/qqmlbinding/data/unknownProperty.qml b/tests/auto/qml/qqmlbinding/data/unknownProperty.qml
new file mode 100644
index 0000000000..36157bb4e7
--- /dev/null
+++ b/tests/auto/qml/qqmlbinding/data/unknownProperty.qml
@@ -0,0 +1,11 @@
+import QtQuick 2.0
+
+Item {
+    id: root
+
+    Binding {
+        target: root
+        property: "unknown"
+        value: 42
+    }
+}
diff --git a/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp b/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
index 2d267cc668..3e49f3b3c4 100644
--- a/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
+++ b/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
@@ -50,6 +50,8 @@ private slots:
     void restoreBindingWithLoop();
     void restoreBindingWithoutCrash();
     void deletedObject();
+    void warningOnUnknownProperty();
+    void warningOnReadOnlyProperty();
 
 private:
     QQmlEngine engine;
@@ -224,6 +226,38 @@ void tst_qqmlbinding::deletedObject()
     delete rect;
 }
 
+void tst_qqmlbinding::warningOnUnknownProperty()
+{
+    QQmlTestMessageHandler messageHandler;
+
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("unknownProperty.qml"));
+    QQuickItem *item = qobject_cast<QQuickItem*>(c.create());
+    QVERIFY(item);
+    delete item;
+
+    QCOMPARE(messageHandler.messages().count(), 1);
+
+    const QString expectedMessage = c.url().toString() + QLatin1String(":6:5: QML Binding: Property 'unknown' does not exist on Item.");
+    QCOMPARE(messageHandler.messages().first(), expectedMessage);
+}
+
+void tst_qqmlbinding::warningOnReadOnlyProperty()
+{
+    QQmlTestMessageHandler messageHandler;
+
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("readonlyProperty.qml"));
+    QQuickItem *item = qobject_cast<QQuickItem*>(c.create());
+    QVERIFY(item);
+    delete item;
+
+    QCOMPARE(messageHandler.messages().count(), 1);
+
+    const QString expectedMessage = c.url().toString() + QLatin1String(":8:5: QML Binding: Property 'name' on Item is read-only.");
+    QCOMPARE(messageHandler.messages().first(), expectedMessage);
+}
+
 QTEST_MAIN(tst_qqmlbinding)
 
 #include "tst_qqmlbinding.moc"