Fix bindings on properties in grouped value type properties

... such as
    point.x: { someExpression }

This requires special handling to install the QQmlBinding not on the
value type itself (not possible) but on the point property itself.

Fixes tst_qqmllanguage::valueTypes

Change-Id: I8f95379e1872dff7cdcc0480c229a5e68f3cf575
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

2 files changed, 36 insertions, 12 deletions

diff --git a/src/qml/qml/qqmlobjectcreator.cpp b/src/qml/qml/qqmlobjectcreator.cpp
index 292df56f24..b137d31dbb 100644
--- a/src/qml/qml/qqmlobjectcreator.cpp
+++ b/src/qml/qml/qqmlobjectcreator.cpp
@@ -480,6 +480,8 @@ QmlObjectCreator::QmlObjectCreator(QQmlContextData *parentContext, QQmlCompiledD
     , vmeMetaObjectData(compiledData->datas)
     , compiledData(compiledData)
     , _qobject(0)
+    , _qobjectForBindings(0)
+    , _valueTypeProperty(0)
     , _compiledObject(0)
     , _ddata(0)
     , _propertyCache(0)
@@ -1001,7 +1003,7 @@ bool QmlObjectCreator::setPropertyValue(QQmlPropertyData *property, int bindingI
         const int id = attachedType->attachedPropertiesId();
         QObject *qmlObject = qmlAttachedPropertiesObjectById(id, _qobject);
         QQmlRefPointer<QQmlPropertyCache> cache = QQmlEnginePrivate::get(engine)->cache(qmlObject);
-        if (!populateInstance(binding->value.objectIndex, qmlObject, cache, _qobject))
+        if (!populateInstance(binding->value.objectIndex, qmlObject, cache, _qobject, /*value type property*/0))
             return false;
         return true;
     }
@@ -1028,7 +1030,9 @@ bool QmlObjectCreator::setPropertyValue(QQmlPropertyData *property, int bindingI
             QQmlEnginePrivate *enginePrivate = QQmlEnginePrivate::get(engine);
             QQmlRefPointer<QQmlPropertyCache> groupedObjCache;
             QObject *groupedObjInstance = 0;
+            QObject *objForBindings = _qobjectForBindings;
             QQmlValueType *valueType = 0;
+            QQmlPropertyData *valueTypeProperty = 0;
 
             if (QQmlValueTypeFactory::isValueType(property->propType)) {
                 valueType = QQmlValueTypeFactory::valueType(property->propType);
@@ -1041,13 +1045,13 @@ bool QmlObjectCreator::setPropertyValue(QQmlPropertyData *property, int bindingI
 
                 groupedObjCache = enginePrivate->cache(valueType);
                 groupedObjInstance = valueType;
+                valueTypeProperty = property;
             } else {
                 groupedObjCache = enginePrivate->propertyCacheForType(property->propType);
                 if (!groupedObjCache) {
                     recordError(binding->location, tr("Invalid grouped property access"));
                     return false;
                 }
-                groupedObjInstance = valueType;
 
                 void *argv[1] = { &groupedObjInstance };
                 QMetaObject::metacall(_qobject, QMetaObject::ReadProperty, property->coreIndex, argv);
@@ -1055,9 +1059,11 @@ bool QmlObjectCreator::setPropertyValue(QQmlPropertyData *property, int bindingI
                     recordError(binding->location, tr("Cannot set properties on %1 as it is null").arg(stringAt(binding->propertyNameIndex)));
                     return false;
                 }
+
+                objForBindings = groupedObjInstance;
             }
 
-            if (!populateInstance(binding->value.objectIndex, groupedObjInstance, groupedObjCache, _qobject))
+            if (!populateInstance(binding->value.objectIndex, groupedObjInstance, groupedObjCache, objForBindings, valueTypeProperty))
                 return false;
 
             if (valueType)
@@ -1084,7 +1090,17 @@ bool QmlObjectCreator::setPropertyValue(QQmlPropertyData *property, int bindingI
         } else {
             QQmlBinding *qmlBinding = new QQmlBinding(function, _qobject, context,
                                                       QString(), 0, 0); // ###
-            qmlBinding->setTarget(_qobject, *property, context);
+
+            // When writing bindings to grouped properties implemented as value types,
+            // such as point.x: { someExpression; }, then the binding is installed on
+            // the point property (_qobjectForBindings) and after evaluating the expression,
+            // the result is written to a value type virtual property, that contains the sub-index
+            // of the "x" property.
+            QQmlPropertyData targetCorePropertyData = *property;
+            if (_valueTypeProperty)
+                targetCorePropertyData = QQmlPropertyPrivate::saveValueType(*_valueTypeProperty, _qobject->metaObject(), property->coreIndex, engine);
+
+            qmlBinding->setTarget(_qobjectForBindings, targetCorePropertyData, context);
             qmlBinding->addToObject();
 
             _createdBindings[bindingIndex] = qmlBinding;
@@ -1252,7 +1268,7 @@ QObject *QmlObjectCreator::createInstance(int index, QObject *parent)
         QQmlRefPointer<QQmlPropertyCache> cache = propertyCaches.value(index);
         Q_ASSERT(!cache.isNull());
 
-        if (!populateInstance(index, instance, cache, _qobject))
+        if (!populateInstance(index, instance, cache, _qobject, /*value type property*/0))
             return 0;
     }
 
@@ -1304,17 +1320,20 @@ void QmlObjectCreator::finalize()
     }
 }
 
-bool QmlObjectCreator::populateInstance(int index, QObject *instance, QQmlRefPointer<QQmlPropertyCache> cache, QObject *scopeObjectForJavaScript)
+bool QmlObjectCreator::populateInstance(int index, QObject *instance, QQmlRefPointer<QQmlPropertyCache> cache,
+                                        QObject *scopeObjectForBindings, QQmlPropertyData *valueTypeProperty)
 {
     const QV4::CompiledData::Object *obj = qmlUnit->objectAt(index);
 
-    if (!scopeObjectForJavaScript)
-        scopeObjectForJavaScript = instance;
+    if (!scopeObjectForBindings)
+        scopeObjectForBindings = instance;
 
     QQmlData *declarativeData = QQmlData::get(instance, /*create*/true);
 
     qSwap(_propertyCache, cache);
     qSwap(_qobject, instance);
+    qSwap(_qobjectForBindings, scopeObjectForBindings);
+    qSwap(_valueTypeProperty, valueTypeProperty);
     qSwap(_compiledObject, obj);
     qSwap(_ddata, declarativeData);
 
@@ -1322,13 +1341,13 @@ bool QmlObjectCreator::populateInstance(int index, QObject *instance, QQmlRefPoi
     const QByteArray data = vmeMetaObjectData.value(index);
     if (!data.isEmpty()) {
         // install on _object
-        vmeMetaObject = new QQmlVMEMetaObject(_qobject, _propertyCache, reinterpret_cast<const QQmlVMEMetaData*>(data.constData()));
+        vmeMetaObject = new QQmlVMEMetaObject(_qobjectForBindings, _propertyCache, reinterpret_cast<const QQmlVMEMetaData*>(data.constData()));
         if (_ddata->propertyCache)
             _ddata->propertyCache->release();
         _ddata->propertyCache = _propertyCache;
         _ddata->propertyCache->addref();
     } else {
-        vmeMetaObject = QQmlVMEMetaObject::get(_qobject);
+        vmeMetaObject = QQmlVMEMetaObject::get(_qobjectForBindings);
     }
 
     _ddata->lineNumber = _compiledObject->location.line;
@@ -1341,7 +1360,7 @@ bool QmlObjectCreator::populateInstance(int index, QObject *instance, QQmlRefPoi
 
     QV4::ExecutionEngine *v4 = QV8Engine::getV4(engine);
     QV4::Scope valueScope(v4);
-    QV4::ScopedValue scopeObject(valueScope, QV4::QmlContextWrapper::qmlScope(QV8Engine::get(engine), context, scopeObjectForJavaScript));
+    QV4::ScopedValue scopeObject(valueScope, QV4::QmlContextWrapper::qmlScope(QV8Engine::get(engine), context, _qobjectForBindings));
     QV4::QmlBindingWrapper *qmlBindingWrapper = new (v4->memoryManager) QV4::QmlBindingWrapper(v4->rootContext, scopeObject->asObject());
     QV4::ScopedValue qmlScopeFunction(valueScope, QV4::Value::fromObject(qmlBindingWrapper));
     QV4::ExecutionContext *qmlContext = qmlBindingWrapper->context();
@@ -1360,6 +1379,8 @@ bool QmlObjectCreator::populateInstance(int index, QObject *instance, QQmlRefPoi
     qSwap(_propertyCache, cache);
     qSwap(_ddata, declarativeData);
     qSwap(_compiledObject, obj);
+    qSwap(_valueTypeProperty, valueTypeProperty);
+    qSwap(_qobjectForBindings, scopeObjectForBindings);
     qSwap(_qobject, instance);
 
     return errors.isEmpty();
diff --git a/src/qml/qml/qqmlobjectcreator_p.h b/src/qml/qml/qqmlobjectcreator_p.h
index fe3a4bb00a..131271c5c6 100644
--- a/src/qml/qml/qqmlobjectcreator_p.h
+++ b/src/qml/qml/qqmlobjectcreator_p.h
@@ -127,7 +127,8 @@ public:
 private:
     QObject *createInstance(int index, QObject *parent = 0);
 
-    bool populateInstance(int index, QObject *instance, QQmlRefPointer<QQmlPropertyCache> cache, QObject *scopeObjectForJavaScript);
+    bool populateInstance(int index, QObject *instance, QQmlRefPointer<QQmlPropertyCache> cache,
+                          QObject *scopeObjectForJavaScript, QQmlPropertyData *valueTypeProperty);
 
     void setupBindings();
     bool setPropertyValue(QQmlPropertyData *property, int index, const QV4::CompiledData::Binding *binding);
@@ -146,6 +147,8 @@ private:
     QQmlCompiledData *compiledData;
 
     QObject *_qobject;
+    QObject *_qobjectForBindings;
+    QQmlPropertyData *_valueTypeProperty; // belongs to _qobjectForBindings's property cache
     const QV4::CompiledData::Object *_compiledObject;
     QQmlData *_ddata;
     QQmlRefPointer<QQmlPropertyCache> _propertyCache;