Fix a crash in the QIviSimulationEngine when using animations

The code handles now read and write of properties using the
staticMetaObject correctly.
Added more internal documentation for it and a autotest.

Change-Id: Iddceeebcf5317ddb3a6986d82febc81bd374b575
Fixes: AUTOSUITE-727
Reviewed-by: Robert Griebl <robert.griebl@pelagicore.com>

3 files changed, 55 insertions, 3 deletions

diff --git a/src/ivicore/qivisimulationproxy.cpp b/src/ivicore/qivisimulationproxy.cpp
index 8800f78..7f2ab00 100644
--- a/src/ivicore/qivisimulationproxy.cpp
+++ b/src/ivicore/qivisimulationproxy.cpp
@@ -82,6 +82,18 @@ int QIviSimulationProxyBase::qt_metacall(QMetaObject::Call call, int methodId, v
     if (m_noSimulationEngine)
         return -1;
 
+    // Special handling for the artificial "Base" property.
+    // All other properties are forwarded to the qt_metacall generated by moc which translates the
+    // absolute id's back to relative ones
+    if (call == QMetaObject::ReadProperty || call == QMetaObject::WriteProperty) {
+        int basePropertyIndex = m_staticMetaObject->indexOfProperty("Base");
+        if (methodId == basePropertyIndex) {
+            void *_v = a[0];
+            *reinterpret_cast< QObject**>(_v) = m_instance;
+            return -1;
+        }
+    }
+
     if (call == QMetaObject::InvokeMetaMethod) {
         // When a forwarded signal from the registered instance gets in. Directly call the signal here as well
         if (sender() == m_instance) {
@@ -89,6 +101,8 @@ int QIviSimulationProxyBase::qt_metacall(QMetaObject::Call call, int methodId, v
             QMetaObject::activate(this, m_staticMetaObject, methodId - m_staticMetaObject->methodOffset(), a);
             return 0;
         }
+        // As we don't derive from the MetaObject of m_instance, we need to use the methodMap to
+        // translate our methodId to the methodId for m_instance
         return m_instance->qt_metacall(call, m_methodMap.key(methodId), a);
     }
     return m_instance->qt_metacall(call, methodId, a);
diff --git a/src/ivicore/qivisimulationproxy.h b/src/ivicore/qivisimulationproxy.h
index f441b1c..8e23e9c 100644
--- a/src/ivicore/qivisimulationproxy.h
+++ b/src/ivicore/qivisimulationproxy.h
@@ -152,9 +152,9 @@ namespace qtivi_private {
                 return;
             Q_ASSERT_X(m_instance, "qt_static_metacall()", "QIviSimulationProxy::registerInstance needs to be called first");
             // As the class acts as a proxy, forward all calls here to the registered instance
-            if (call == QMetaObject::ReadProperty) {
-                void *_v = a[0];
-                *reinterpret_cast< T**>(_v) = m_instance;
+            // The methodIds start at 0 for the first property of this class. We need to add the
+            // offset to get the absolute property index for the normal qt_metacall
+            if (call == QMetaObject::ReadProperty || call == QMetaObject::WriteProperty) {
                 obj->qt_metacall(call, methodId + staticMetaObject.propertyOffset(), a);
                 return;
             }
diff --git a/tests/auto/core/qivisimulationengine/tst_qivisimulationengine.cpp b/tests/auto/core/qivisimulationengine/tst_qivisimulationengine.cpp
index a38bc9d..3bd1299 100644
--- a/tests/auto/core/qivisimulationengine/tst_qivisimulationengine.cpp
+++ b/tests/auto/core/qivisimulationengine/tst_qivisimulationengine.cpp
@@ -252,6 +252,7 @@ private Q_SLOTS:
     void testPropertyWrite();
     void testPropertyWriteDerived_data();
     void testPropertyWriteDerived();
+    void testAnimations();
 
     void testFunctionCalls_data();
     void testFunctionCalls();
@@ -560,6 +561,43 @@ void tst_QIviSimulationEngine::testPropertyWriteDerived()
     QCOMPARE(obj->property("bindingProperty"), value);
 }
 
+//Animations use a different way to access the properties, so we need to test this explicitly
+void tst_QIviSimulationEngine::testAnimations()
+{
+    QIviSimulationEngine engine;
+
+    DerivedClass testObject;
+    engine.registerSimulationInstance<DerivedClass>(&testObject, "TestAPI", 1, 0, "DerivedClass");
+    QSignalSpy spy(&testObject, SIGNAL(propertyInBaseChanged(int)));
+
+    QByteArray qml ("import QtQuick 2.0; \n\
+                     import TestAPI 1.0; \n\
+                     DerivedClass { \n\
+                        id: backend \n\
+                        property var animation: SequentialAnimation { \n\
+                            NumberAnimation { target: backend; property: \"propertyInBase\"; from: 0; to: 130; duration: 500 } \n\
+                            ScriptAction { script: backend.animationDone() } \n\
+                            running: true \n\
+                        } \n\
+                        signal animationDone(); \n\
+                     }");
+
+    QQmlComponent component(&engine);
+    component.setData(qml, QUrl());
+    QScopedPointer<QObject> obj(component.create());
+    QVERIFY2(obj, qPrintable(component.errorString()));
+
+    //wait until the animation ended
+    QSignalSpy animationSpy(obj.data(), SIGNAL(animationDone()));
+    animationSpy.wait();
+
+    //Check that the animation has reached it's final value
+    QCOMPARE(obj->property("propertyInBase"), 130);
+
+    //we expect at least 10 animation steps
+    QVERIFY2(spy.count() > 10, qPrintable(QStringLiteral("Emitted signals: ") + QString::number(spy.count())));
+}
+
 void tst_QIviSimulationEngine::testFunctionCalls_data()
 {
     QTest::addColumn<QByteArray>("function");