Fix #633: Check if this extends wrapper #634
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Invert the extend check in Type::cast so that it is checking if this instance extends wrapper and therefor this can be cast to Wrapper.
| @@ -556,7 +556,7 @@ class Type { | |||
| template <class T, class Clazz> | |||
| template<class Wrapper> | |||
| Wrapper ObjectWrapper<T, Clazz>::cast() const { | |||
| if(!Wrapper::Class::getType()->extends(m_valueType)) { | |||
| if(!m_valueType->extends(Wrapper::Class::getType())) { | |||
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ObjectWrapper<T, Clazz>::cast() - is an unsafe static cast which allows downcasts to child classes. Thats why we check if Wrapper::Class::getType()->extends(m_valueType).
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I thought it was just for type safe casting hence the checks being there. The reason I made this change was so cast could be used in oatpp-protobuf to perform casts from the Void reference to oatpp::Vector<AbstractDynamicObject> for repeated fields. Without this change even though Vector<AbstractDynamicObject> is a parent of DynamicClass there is no clean way to cast from the Void objects to Vector<AbstractDynamicObject> and the same error seen in #595 occurs.
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I did try to use assignment copy and played around with that a little but could only seem to get raw static casts to work, which is what is being done in StandardCollection::PolymorphicDispatcher so maybe that is the only answer for now
Invert the extend check in Type::cast so that it is checking if this instance extends wrapper and therefor this can be cast to Wrapper.