Throw type errors when attempting to mutate read-only sequence properties

Calling for example Qt.application.arguments.push("...") should throw an
exception.

Task-number: QTBUG-67774
Change-Id: Ifd5cd3357dde510cca77b9b32c9f55f8f72837ff
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

2 files changed, 26 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlecmascript/data/assignSequenceTypes.8.qml b/tests/auto/qml/qqmlecmascript/data/assignSequenceTypes.8.qml
new file mode 100644
index 0000000000..3f838fe8f2
--- /dev/null
+++ b/tests/auto/qml/qqmlecmascript/data/assignSequenceTypes.8.qml
@@ -0,0 +1,16 @@
+import QtQml 2.0
+QtObject {
+    function tryWritingReadOnlySequence() {
+        try {
+            Qt.application.arguments.push("hello")
+        } catch (e) {
+
+            try {
+                Qt.application.arguments.sort()
+            } catch (e) {
+                return true
+            }
+        }
+        return false
+    }
+}
diff --git a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
index 5a7ef01eea..b6f753b313 100644
--- a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
+++ b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
@@ -5784,6 +5784,16 @@ void tst_qqmlecmascript::assignSequenceTypes()
     QCOMPARE(msco5->urlListProperty(), (QList<QUrl>() << QUrl(testFileUrl("example.html")) << QUrl(testFileUrl("example2.html"))));
     delete object;
     }
+
+    {
+    QQmlComponent component(&engine, testFileUrl("assignSequenceTypes.8.qml"));
+    QScopedPointer<QObject> object(component.create());
+    QVERIFY(object != nullptr);
+    QVariant result;
+    QMetaObject::invokeMethod(object.data(), "tryWritingReadOnlySequence", Q_RETURN_ARG(QVariant, result));
+    QVERIFY(result.type() == QVariant::Bool);
+    QVERIFY(result.toBool());
+    }
 }
 
 // Test that assigning a null object works