This diagnostic is not currently implemented.
Ineffective type group filter attribute with no permitted base types
Brevity
Warning
There are no permitted base types along with OnlyPermitSpecifiedTypes
which prohibits all types except for the exact ones.
See how the type group filtering system works at the docs.
class GenericType
<
// GA0045 will appear here
[FilterAbstractClasses(FilterType.Permitted)]
// GA0045 will appear here
[FilterSealedClasses(FilterType.Prohibited)]
// GA0045 will appear here
[OnlyPermitSpecifiedTypeGroups]
[OnlyPermitSpecifiedTypes]
[PermittedTypes(typeof(string), typeof(int), typeof(object))]
T
>;