Allow proper registration of value types

You can now have an extension object on a value type that offers
additional properties. This is how we model the QtQuick value types. It
allows us to retrieve the extension's metaobject without using the
virtual functions in the value type provider.

As before, this mechanism is still rather dangerous and not fit for
public consumption. It relies on the extension object having exactly the
same layout as the original value type, and it hides any properties the
original value type might expose.

Furthermore we enforce now that gadgets should have lowercase names.
The ones that didn't before are split up into an anonymous value type
and a namespace that contains all the addressable bits.

Task-number: QTBUG-82443
Change-Id: Ic93d6764538d6ccc0774b3c5648eee08ba0939c0
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 72 insertions, 57 deletions

diff --git a/src/qml/qml/qqml.h b/src/qml/qml/qqml.h
index 4c3454e7b4..f399924447 100644
--- a/src/qml/qml/qqml.h
+++ b/src/qml/qml/qqml.h
@@ -166,13 +166,14 @@ int qmlRegisterAnonymousType(const char *uri, int versionMajor)
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, 0), nullptr, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, 0), nullptr,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -198,14 +199,15 @@ int qmlRegisterUncreatableType(const char *uri, int versionMajor, int versionMin
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T>>(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr,
         nullptr,
         reason,
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -228,14 +230,15 @@ int qmlRegisterUncreatableType(const char *uri, int versionMajor, int versionMin
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr,
         nullptr,
         reason,
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -265,14 +268,15 @@ int qmlRegisterExtendedUncreatableType(const char *uri, int versionMajor, int ve
 
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr,
         nullptr,
         reason,
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         attached,
         attachedMetaObject,
@@ -281,7 +285,7 @@ int qmlRegisterExtendedUncreatableType(const char *uri, int versionMajor, int ve
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueSource>::cast(),
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueInterceptor>::cast(),
 
-        QQmlPrivate::createParent<E>, &E::staticMetaObject,
+        QQmlPrivate::ExtendedType<E>::createParent, QQmlPrivate::ExtendedType<E>::staticMetaObject(),
 
         nullptr,
         QTypeRevision::zero()
@@ -302,14 +306,15 @@ int qmlRegisterExtendedUncreatableType(const char *uri, int versionMajor, int ve
 
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr,
         nullptr,
         reason,
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         attached,
         attachedMetaObject,
@@ -318,7 +323,7 @@ int qmlRegisterExtendedUncreatableType(const char *uri, int versionMajor, int ve
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueSource>::cast(),
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueInterceptor>::cast(),
 
-        QQmlPrivate::createParent<E>, &E::staticMetaObject,
+        QQmlPrivate::ExtendedType<E>::createParent, QQmlPrivate::ExtendedType<E>::staticMetaObject(),
 
         nullptr,
         QTypeRevision::fromMinorVersion(metaObjectRevision)
@@ -334,12 +339,13 @@ int qmlRegisterType(const char *uri, int versionMajor, int versionMinor, const c
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -362,12 +368,13 @@ int qmlRegisterType(const char *uri, int versionMajor, int versionMinor, const c
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -390,12 +397,13 @@ int qmlRegisterRevision(const char *uri, int versionMajor, int versionMinor)
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), nullptr, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), nullptr,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -418,14 +426,15 @@ int qmlRegisterExtendedType(const char *uri, int versionMajor)
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
         0,
         nullptr,
         nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, 0), nullptr, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, 0), nullptr,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -434,7 +443,7 @@ int qmlRegisterExtendedType(const char *uri, int versionMajor)
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueSource>::cast(),
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueInterceptor>::cast(),
 
-        QQmlPrivate::createParent<E>, &E::staticMetaObject,
+        QQmlPrivate::ExtendedType<E>::createParent, QQmlPrivate::ExtendedType<E>::staticMetaObject(),
 
         nullptr,
         QTypeRevision::zero()
@@ -456,12 +465,13 @@ int qmlRegisterExtendedType(const char *uri, int versionMajor, int versionMinor,
 
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         attached,
         attachedMetaObject,
@@ -470,7 +480,7 @@ int qmlRegisterExtendedType(const char *uri, int versionMajor, int versionMinor,
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueSource>::cast(),
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueInterceptor>::cast(),
 
-        QQmlPrivate::createParent<E>, &E::staticMetaObject,
+        QQmlPrivate::ExtendedType<E>::createParent, QQmlPrivate::ExtendedType<E>::staticMetaObject(),
 
         nullptr,
         QTypeRevision::zero()
@@ -484,6 +494,8 @@ int qmlRegisterInterface(const char *uri, int versionMajor)
 {
     QQmlPrivate::RegisterInterface qmlInterface = {
         0,
+        // An interface is not a QObject itself but is typically casted to one.
+        // Therefore, we still want the pointer.
         QMetaType::fromType<T *>(),
         QMetaType::fromType<QQmlListProperty<T> >(),
         qobject_interface_iid<T *>(),
@@ -501,12 +513,13 @@ int qmlRegisterCustomType(const char *uri, int versionMajor, int versionMinor,
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -530,12 +543,13 @@ int qmlRegisterCustomType(const char *uri, int versionMajor, int versionMinor,
 {
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         QQmlPrivate::attachedPropertiesFunc<T>(),
         QQmlPrivate::attachedPropertiesMetaObject<T>(),
@@ -566,12 +580,13 @@ int qmlRegisterCustomExtendedType(const char *uri, int versionMajor, int version
 
     QQmlPrivate::RegisterType type = {
         0,
-        QMetaType::fromType<T *>(),
-        QMetaType::fromType<QQmlListProperty<T> >(),
-        sizeof(T), QQmlPrivate::createInto<T>, nullptr,
+        QQmlPrivate::QmlMetaType<T>::self(),
+        QQmlPrivate::QmlMetaType<T>::list(),
+        sizeof(T), QQmlPrivate::Constructors<T>::createInto, nullptr,
         QString(),
 
-        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName, &T::staticMetaObject,
+        uri, QTypeRevision::fromVersion(versionMajor, versionMinor), qmlName,
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
 
         attached,
         attachedMetaObject,
@@ -580,7 +595,7 @@ int qmlRegisterCustomExtendedType(const char *uri, int versionMajor, int version
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueSource>::cast(),
         QQmlPrivate::StaticCastSelector<T,QQmlPropertyValueInterceptor>::cast(),
 
-        QQmlPrivate::createParent<E>, &E::staticMetaObject,
+        QQmlPrivate::ExtendedType<E>::createParent, QQmlPrivate::ExtendedType<E>::staticMetaObject(),
 
         parser,
         QTypeRevision::zero()
@@ -659,8 +674,8 @@ inline int qmlRegisterSingletonType(
         typeName,
         nullptr,
         callback,
-        &T::staticMetaObject,
-        QMetaType::fromType<T *>(),
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
+        QQmlPrivate::QmlMetaType<T>::self(),
         QTypeRevision::zero()
     };
 
@@ -684,8 +699,8 @@ inline int qmlRegisterSingletonType(const char *uri, int versionMajor, int versi
         typeName,
         nullptr,
         callback,
-        &T::staticMetaObject,
-        QMetaType::fromType<T *>(),
+        QQmlPrivate::StaticMetaObject<T>::staticMetaObject(),
+        QQmlPrivate::QmlMetaType<T>::self(),
         QTypeRevision::zero()
     };
 
@@ -751,7 +766,7 @@ struct QmlTypeAndRevisionsRegistration<T, Resolved, Extended, false, false> {
     static void registerTypeAndRevisions(const char *uri, int versionMajor, QList<int> *qmlTypeIds)
     {
         QQmlPrivate::qmlRegisterTypeAndRevisions<Resolved, Extended>(
-                    uri, versionMajor, &T::staticMetaObject, qmlTypeIds);
+                    uri, versionMajor, QQmlPrivate::StaticMetaObject<T>::staticMetaObject(), qmlTypeIds);
     }
 };
 
@@ -760,7 +775,7 @@ struct QmlTypeAndRevisionsRegistration<T, Resolved, void, true, false> {
     static void registerTypeAndRevisions(const char *uri, int versionMajor, QList<int> *qmlTypeIds)
     {
         QQmlPrivate::qmlRegisterSingletonAndRevisions<Resolved>(
-                    uri, versionMajor, &T::staticMetaObject, qmlTypeIds);
+                    uri, versionMajor, QQmlPrivate::StaticMetaObject<T>::staticMetaObject(), qmlTypeIds);
     }
 };