Make it possible to handle pointers to QObject derived in QML.

This way, properties of QObject derived types can be read in QML
code for example:

 Q_PROPERTY(MyObject* obj READ obj CONSTANT)

Previously, only QObject* types could be read by QML:

 Q_PROPERTY(QObject* obj READ obj CONSTANT)

This meant that multiple properties and methods had to be created
for classes which were relevant to both QML and non-QML code.

This patch lifts that restriction.

As a consequence, we can also remove a Q_EXPECT_FAIL from
the qqmllanguage unit test. That test was introduced in
commit 92562eacbc3c (Allow signal parameters which are custom QML
object-types, 2012-07-13) to document knowledge of the limitation
while fixing it as much as possible.

Task-number: QTBUG-26662

Change-Id: Ic85fa73c6f3655189438ec509765bae2eab9993a
Reviewed-by: Alan Alpert (Personal) <416365416c@gmail.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlcontext/tst_qqmlcontext.cpp b/tests/auto/qml/qqmlcontext/tst_qqmlcontext.cpp
index e0c20307a8..4f21231184 100644
--- a/tests/auto/qml/qqmlcontext/tst_qqmlcontext.cpp
+++ b/tests/auto/qml/qqmlcontext/tst_qqmlcontext.cpp
@@ -72,6 +72,7 @@ private slots:
 
     void qtbug_22535();
     void evalAfterInvalidate();
+    void qobjectDerived();
 
 private:
     QQmlEngine engine;
@@ -659,6 +660,26 @@ void tst_qqmlcontext::evalAfterInvalidate()
     QCoreApplication::processEvents();
 }
 
+void tst_qqmlcontext::qobjectDerived()
+{
+    QQmlEngine engine;
+    QQmlComponent component(&engine, testFileUrl("refreshExpressions.qml"));
+
+    CountCommand command;
+    // This test is similar to refreshExpressions, but with the key difference that
+    // we use the QVariant overload of setContextProperty. That way, we test that
+    // QVariant knowledge that it contains a QObject derived pointer is used.
+    engine.rootContext()->setContextProperty("countCommand", QVariant::fromValue(&command));
+
+    // We use a fresh context here to bypass any root-context optimizations in
+    // the engine
+    QQmlContext context(engine.rootContext());
+
+    QObject *o1 = component.create(&context);
+
+    QCOMPARE(command.count, 2);
+}
+
 QTEST_MAIN(tst_qqmlcontext)
 
 #include "tst_qqmlcontext.moc"