QtQml: Consider value types when looking for metaobjects

We have quite a few types with only extension metaobjects now. Move the
functionality to retrieve the metaobject into QQmlType where it belongs.

Pick-to: 6.7 6.6
Fixes: QTBUG-119829
Change-Id: I2b99b1a305d8726547ae0512d3c832799a4e4b04
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Olivier De Cannière <olivier.decanniere@qt.io>

10 files changed, 152 insertions, 85 deletions

diff --git a/src/qml/jsruntime/qv4jscall_p.h b/src/qml/jsruntime/qv4jscall_p.h
index e8896ce19d..ef4b742590 100644
--- a/src/qml/jsruntime/qv4jscall_p.h
+++ b/src/qml/jsruntime/qv4jscall_p.h
@@ -384,7 +384,7 @@ inline ReturnedValue coerce(
 
     if (void *target = QQmlValueTypeProvider::heapCreateValueType(qmlType, value)) {
         Heap::QQmlValueTypeWrapper *wrapper = engine->memoryManager->allocate<QQmlValueTypeWrapper>(
-                nullptr, metaType, QQmlMetaType::metaObjectForValueType(qmlType),
+                nullptr, metaType, qmlType.metaObjectForValueType(),
                 nullptr, -1, Heap::ReferenceObject::NoFlag);
         Q_ASSERT(!wrapper->gadgetPtr());
         wrapper->setGadgetPtr(target);
diff --git a/src/qml/qml/qqmlglobal.cpp b/src/qml/qml/qqmlglobal.cpp
index 061a55a9e6..1273067187 100644
--- a/src/qml/qml/qqmlglobal.cpp
+++ b/src/qml/qml/qqmlglobal.cpp
@@ -445,29 +445,30 @@ bool createOrConstructValueType(
         const QQmlType &targetType, const QV4::Value &source,
         Allocate &&allocate, DefaultConstruct &&defaultConstruct)
 {
-    if (const QMetaObject *targetMetaObject = QQmlMetaType::metaObjectForValueType(targetType)) {
-        const auto warn = [&]() {
-            qWarning().noquote()
-                    << "Could not find any constructor for value type"
-                    << targetMetaObject->className() << "to call with value"
-                    << source.toQStringNoThrow();
-        };
-
-        if (targetType.canPopulateValueType()) {
-            if (source.isObject() && targetMetaObject) {
+    const auto warn = [&](const QMetaObject *targetMetaObject) {
+        qWarning().noquote()
+                << "Could not find any constructor for value type"
+                << targetMetaObject->className() << "to call with value"
+                << source.toQStringNoThrow();
+    };
+
+    if (targetType.canPopulateValueType()) {
+        if (const QMetaObject *targetMetaObject = targetType.metaObjectForValueType()) {
+            if (source.isObject()) {
                 doWriteProperties(targetMetaObject, defaultConstruct(), source);
                 return true;
             }
             if (targetType.canConstructValueType()) {
                 if (fromMatchingType(targetMetaObject, source, allocate))
                     return true;
-                warn();
-
+                warn(targetMetaObject);
             }
-        } else if (targetType.canConstructValueType()) {
+        }
+    } else if (targetType.canConstructValueType()) {
+        if (const QMetaObject *targetMetaObject = targetType.metaObjectForValueType()) {
             if (fromMatchingType(targetMetaObject, source, allocate))
                 return true;
-            warn();
+            warn(targetMetaObject);
         }
     }
 
@@ -489,15 +490,15 @@ bool createOrConstructValueType(
         const QQmlType &targetType, QMetaType sourceMetaType, void *source,
         Allocate &&allocate, DefaultConstruct &&defaultConstruct)
 {
-    if (const QMetaObject *targetMetaObject = QQmlMetaType::metaObjectForValueType(targetType)) {
-        const auto warn = [&]() {
-            qWarning().noquote()
-                << "Could not find any constructor for value type"
-                << targetMetaObject->className() << "to call with value" << source;
-        };
 
-        if (targetType.canPopulateValueType()) {
+    const auto warn = [&](const QMetaObject *targetMetaObject) {
+        qWarning().noquote()
+            << "Could not find any constructor for value type"
+            << targetMetaObject->className() << "to call with value" << source;
+    };
 
+    if (targetType.canPopulateValueType()) {
+        if (const QMetaObject *targetMetaObject = targetType.metaObjectForValueType()) {
             if (const QMetaObject *sourceMetaObject
                     = QQmlMetaType::metaObjectForValueType(sourceMetaType)) {
                 doWriteProperties(
@@ -529,15 +530,17 @@ bool createOrConstructValueType(
                 return true;
             }
         }
+    }
 
-        if (targetType.canConstructValueType()) {
+    if (targetType.canConstructValueType()) {
+        if (const QMetaObject *targetMetaObject = targetType.metaObjectForValueType()) {
             if (fromMatchingType(targetMetaObject, std::forward<Allocate>(allocate),
                                  [&](QMetaType, auto callback) {
                     return callback(sourceMetaType, source);
                 })) {
                 return true;
             }
-            warn();
+            warn(targetMetaObject);
         }
     }
 
@@ -656,11 +659,12 @@ QVariant QQmlValueTypeProvider::createValueType(const QString &s, QMetaType meta
     if (!isConstructibleMetaType(metaType))
         return QVariant();
     const QQmlType type = QQmlMetaType::qmlType(metaType);
-    const QMetaObject *mo = QQmlMetaType::metaObjectForValueType(type);
-    if (mo && type.canConstructValueType()) {
-        QVariant result;
-        if (fromString(mo, s, [&]() { return createVariantData(metaType, &result); }))
-            return result;
+    if (type.canConstructValueType()) {
+        if (const QMetaObject *mo = type.metaObjectForValueType()) {
+            QVariant result;
+            if (fromString(mo, s, [&]() { return createVariantData(metaType, &result); }))
+                return result;
+        }
     }
 
     return fromJSValue(type, s, metaType);
@@ -671,27 +675,29 @@ QVariant QQmlValueTypeProvider::createValueType(const QV4::Value &s, QMetaType m
     if (!isConstructibleMetaType(metaType))
         return QVariant();
     const QQmlType type = QQmlMetaType::qmlType(metaType);
-    if (const QMetaObject *mo = QQmlMetaType::metaObjectForValueType(type)) {
-        const auto warn = [&]() {
-            qWarning().noquote()
-                    << "Could not find any constructor for value type"
-                    << mo->className() << "to call with value" << s.toQStringNoThrow();
-        };
-
-        if (type.canPopulateValueType()) {
+    const auto warn = [&](const QMetaObject *mo) {
+        qWarning().noquote()
+                << "Could not find any constructor for value type"
+                << mo->className() << "to call with value" << s.toQStringNoThrow();
+    };
+
+    if (type.canPopulateValueType()) {
+        if (const QMetaObject *mo = type.metaObject()) {
             QVariant result = byProperties(mo, metaType, s);
             if (result.isValid())
                 return result;
             if (type.canConstructValueType()) {
                 if (fromMatchingType(mo, s, [&]() { return createVariantData(metaType, &result); }))
                     return result;
-                warn();
+                warn(mo);
             }
-        } else if (type.canConstructValueType()) {
+        }
+    } else if (type.canConstructValueType()) {
+        if (const QMetaObject *mo = type.metaObject()) {
             QVariant result;
             if (fromMatchingType(mo, s, [&]() { return createVariantData(metaType, &result); }))
                 return result;
-            warn();
+            warn(mo);
         }
     }
 
@@ -708,27 +714,29 @@ QVariant QQmlValueTypeProvider::createValueType(const QVariant &s, QMetaType met
     if (!isConstructibleMetaType(metaType))
         return QVariant();
     const QQmlType type = QQmlMetaType::qmlType(metaType);
-    if (const QMetaObject *mo = QQmlMetaType::metaObjectForValueType(type)) {
-        const auto warn = [&]() {
-            qWarning().noquote()
-                    << "Could not find any constructor for value type"
-                    << mo->className() << "to call with value" << s;
-        };
-
-        if (type.canPopulateValueType()) {
+    const auto warn = [&](const QMetaObject *mo) {
+        qWarning().noquote()
+                << "Could not find any constructor for value type"
+                << mo->className() << "to call with value" << s;
+    };
+
+    if (type.canPopulateValueType()) {
+        if (const QMetaObject *mo = type.metaObjectForValueType()) {
             QVariant result = byProperties(mo, metaType, s);
             if (result.isValid())
                 return result;
             if (type.canConstructValueType()) {
                 if (fromMatchingType(mo, s, [&]() { return createVariantData(metaType, &result); }))
                     return result;
-                warn();
+                warn(mo);
             }
-        } else if (type.canConstructValueType()) {
+        }
+    } else if (type.canConstructValueType()) {
+        if (const QMetaObject *mo = type.metaObjectForValueType()) {
             QVariant result;
             if (fromMatchingType(mo, s, [&]() { return createVariantData(metaType, &result); }))
                 return result;
-            warn();
+            warn(mo);
         }
     }
 
diff --git a/src/qml/qml/qqmlmetatype.cpp b/src/qml/qml/qqmlmetatype.cpp
index 10bb54fca8..a21c225eba 100644
--- a/src/qml/qml/qqmlmetatype.cpp
+++ b/src/qml/qml/qqmlmetatype.cpp
@@ -1463,8 +1463,15 @@ QQmlPropertyCache::ConstPtr QQmlMetaType::rawPropertyCacheForType(QMetaType meta
         return composite;
 
     const QQmlTypePrivate *type = data->idToType.value(metaType.id());
-    return (type && type->typeId == metaType)
-            ? data->propertyCache(type->baseMetaObject, QTypeRevision())
+    if (!type || type->typeId != metaType)
+        return QQmlPropertyCache::ConstPtr();
+
+    const QMetaObject *metaObject = type->isValueType()
+            ? type->metaObjectForValueType()
+            : type->baseMetaObject;
+
+    return metaObject
+            ? data->propertyCache(metaObject, QTypeRevision())
             : QQmlPropertyCache::ConstPtr();
 }
 
@@ -1898,8 +1905,12 @@ const QMetaObject *QQmlMetaType::metaObjectForValueType(QMetaType metaType)
     // call QObject pointers value types. Explicitly registered types also override
     // the implicit use of gadgets.
     if (!(metaType.flags() & QMetaType::PointerToQObject)) {
-        if (const QMetaObject *mo = metaObjectForValueType(QQmlMetaType::qmlType(metaType)))
-            return mo;
+        const QQmlMetaTypeDataPtr data;
+        const QQmlTypePrivate *type = data->idToType.value(metaType.id());
+        if (type && type->regType == QQmlType::CppType && type->typeId == metaType) {
+            if (const QMetaObject *mo = type->metaObjectForValueType())
+                return mo;
+        }
     }
 
     // If it _is_ a gadget, we can just use it.
diff --git a/src/qml/qml/qqmlmetatype_p.h b/src/qml/qml/qqmlmetatype_p.h
index 3c2b893499..f4870d9db1 100644
--- a/src/qml/qml/qqmlmetatype_p.h
+++ b/src/qml/qml/qqmlmetatype_p.h
@@ -257,26 +257,6 @@ public:
     static bool isValueType(QMetaType type);
     static QQmlValueType *valueType(QMetaType metaType);
     static const QMetaObject *metaObjectForValueType(QMetaType type);
-    static const QMetaObject *metaObjectForValueType(const QQmlType &qmlType)
-    {
-        // Prefer the extension meta object, if any.
-        // Extensions allow registration of non-gadget value types.
-        if (const QMetaObject *extensionMetaObject = qmlType.extensionMetaObject()) {
-            // This may be a namespace even if the original metaType isn't.
-            // You can do such things with QML_FOREIGN declarations.
-            if (extensionMetaObject->metaType().flags() & QMetaType::IsGadget)
-                return extensionMetaObject;
-        }
-
-        if (const QMetaObject *qmlTypeMetaObject = qmlType.metaObject()) {
-            // This may be a namespace even if the original metaType isn't.
-            // You can do such things with QML_FOREIGN declarations.
-            if (qmlTypeMetaObject->metaType().flags() & QMetaType::IsGadget)
-                return qmlTypeMetaObject;
-        }
-
-        return nullptr;
-    }
 
     static QQmlPropertyCache::ConstPtr findPropertyCacheInCompositeTypes(QMetaType t);
     static void registerInternalCompositeType(
diff --git a/src/qml/qml/qqmltype.cpp b/src/qml/qml/qqmltype.cpp
index b3df3a862b..ee5ae374e5 100644
--- a/src/qml/qml/qqmltype.cpp
+++ b/src/qml/qml/qqmltype.cpp
@@ -644,6 +644,11 @@ bool QQmlType::isSequentialContainer() const
     return d && d->regType == SequentialContainerType;
 }
 
+bool QQmlType::isValueType() const
+{
+    return d && d->isValueType();
+}
+
 QMetaType QQmlType::typeId() const
 {
     return d ? d->typeId : QMetaType{};
@@ -661,14 +666,13 @@ QMetaSequence QQmlType::listMetaSequence() const
 
 const QMetaObject *QQmlType::metaObject() const
 {
-    if (!d)
-        return nullptr;
-    const QQmlTypePrivate::ProxyMetaObjects *proxies = d->init();
+    return d ? d->metaObject() : nullptr;
+}
 
-    if (proxies->data.isEmpty())
-        return d->baseMetaObject;
-    else
-        return proxies->data.constFirst().metaObject;
+const QMetaObject *QQmlType::metaObjectForValueType() const
+{
+    Q_ASSERT(d);
+    return d->metaObjectForValueType();
 }
 
 const QMetaObject *QQmlType::baseMetaObject() const
diff --git a/src/qml/qml/qqmltype_p.h b/src/qml/qml/qqmltype_p.h
index c4959cae06..ffffd0fdd9 100644
--- a/src/qml/qml/qqmltype_p.h
+++ b/src/qml/qml/qqmltype_p.h
@@ -96,12 +96,17 @@ public:
     bool isQObjectSingleton() const;
     bool isQJSValueSingleton() const;
     bool isSequentialContainer() const;
+    bool isValueType() const;
 
     QMetaType typeId() const;
     QMetaType qListTypeId() const;
     QMetaSequence listMetaSequence() const;
 
     const QMetaObject *metaObject() const;
+
+    // Precondition: The type is actually a value type!
+    const QMetaObject *metaObjectForValueType() const;
+
     const QMetaObject *baseMetaObject() const;
     QTypeRevision metaObjectRevision() const;
     bool containsRevisionedAttributes() const;
diff --git a/src/qml/qml/qqmltype_p_p.h b/src/qml/qml/qqmltype_p_p.h
index bd77eb5509..8f614eeac2 100644
--- a/src/qml/qml/qqmltype_p_p.h
+++ b/src/qml/qml/qqmltype_p_p.h
@@ -86,6 +86,11 @@ public:
         return regType == QQmlType::CompositeType || regType == QQmlType::CompositeSingletonType;
     }
 
+    bool isValueType() const
+    {
+        return regType == QQmlType::CppType && !(typeId.flags() & QMetaType::PointerToQObject);
+    }
+
     QQmlType resolveCompositeBaseType(QQmlEnginePrivate *engine) const;
     QQmlPropertyCache::ConstPtr compositePropertyCache(QQmlEnginePrivate *engine) const;
 
@@ -192,6 +197,40 @@ public:
         }, ok);
     }
 
+    const QMetaObject *metaObject() const
+    {
+        if (isValueType())
+            return metaObjectForValueType();
+
+        const QQmlTypePrivate::ProxyMetaObjects *proxies = init();
+        return proxies->data.isEmpty()
+                ? baseMetaObject
+                : proxies->data.constFirst().metaObject;
+    }
+
+    const QMetaObject *metaObjectForValueType() const
+    {
+        Q_ASSERT(isValueType());
+
+        // Prefer the extension meta object, if any.
+        // Extensions allow registration of non-gadget value types.
+        if (const QMetaObject *extensionMetaObject = extraData.cppTypeData->extMetaObject) {
+            // This may be a namespace even if the original metaType isn't.
+            // You can do such things with QML_FOREIGN declarations.
+            if (extensionMetaObject->metaType().flags() & QMetaType::IsGadget)
+                return extensionMetaObject;
+        }
+
+        if (baseMetaObject) {
+            // This may be a namespace even if the original metaType isn't.
+            // You can do such things with QML_FOREIGN declarations.
+            if (baseMetaObject->metaType().flags() & QMetaType::IsGadget)
+                return baseMetaObject;
+        }
+
+        return nullptr;
+    }
+
 private:
     mutable QAtomicPointer<const ProxyMetaObjects> proxyMetaObjects;
     mutable QAtomicPointer<const Enums> enums;
diff --git a/src/qml/qml/qqmltypewrapper.cpp b/src/qml/qml/qqmltypewrapper.cpp
index 412c1d6419..0a707d4739 100644
--- a/src/qml/qml/qqmltypewrapper.cpp
+++ b/src/qml/qml/qqmltypewrapper.cpp
@@ -447,11 +447,11 @@ ReturnedValue QQmlTypeWrapper::virtualInstanceOf(const Object *typeObject, const
     if (const QObjectWrapper *objectWrapper = var.as<QObjectWrapper>())
         return instanceOfQObject(typeWrapper, objectWrapper);
 
-    if (const QMetaObject *valueTypeMetaObject
-            = QQmlMetaType::metaObjectForValueType(typeWrapper->d()->type())) {
+    const QQmlType type = typeWrapper->d()->type();
+    if (type.isValueType()) {
         if (const QQmlValueTypeWrapper *valueWrapper = var.as<QQmlValueTypeWrapper>()) {
             return QV4::Encode(QQmlMetaObject::canConvert(valueWrapper->metaObject(),
-                                                          valueTypeMetaObject));
+                                                          type.metaObjectForValueType()));
         }
 
         // We want "foo as valuetype" to return undefined if it doesn't match.
diff --git a/tests/auto/qml/qqmllanguage/data/overrideDefaultProperty.qml b/tests/auto/qml/qqmllanguage/data/overrideDefaultProperty.qml
new file mode 100644
index 0000000000..69f9316c51
--- /dev/null
+++ b/tests/auto/qml/qqmllanguage/data/overrideDefaultProperty.qml
@@ -0,0 +1,6 @@
+import QtQuick
+
+Item {
+    property list<var> data: []
+    Item {}
+}
diff --git a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
index a69cf1a25a..b0f49c94fe 100644
--- a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
+++ b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
@@ -445,6 +445,7 @@ private slots:
     void writeNumberToEnumAlias();
     void badInlineComponentAnnotation();
     void manuallyCallSignalHandler();
+    void overrideDefaultProperty();
 
 private:
     QQmlEngine engine;
@@ -8567,6 +8568,19 @@ void tst_qqmllanguage::manuallyCallSignalHandler()
     }
 }
 
+void tst_qqmllanguage::overrideDefaultProperty()
+{
+    QQmlEngine e;
+    const QUrl url = testFileUrl("overrideDefaultProperty.qml");
+
+    // Should not crash here!
+
+    QQmlComponent c(&e, url);
+    QVERIFY(c.isError());
+    QCOMPARE(c.errorString(),
+             url.toString() + QLatin1String(":5 Cannot assign object to list property \"data\"\n"));
+}
+
 QTEST_MAIN(tst_qqmllanguage)
 
 #include "tst_qqmllanguage.moc"