Help understanding an error message with Type[T] being assigned to T

[d-tw]

Hi,

With the following sample, I have the following error:

from typing import Protocol, TypeVar, Type

SE = TypeVar('SE', bound=Exception)
TE = TypeVar('TE', bound=Exception)

class ExceptionMapper(Protocol[TE]):
    def __call__(self, source_exception: Exception, t_exc_class: Type[TE]) -> TE: ...


def default_mapper(s_exc: Exception, t_exc_class: Type[TE]) -> TE: ...


def with_map_exceptions(
    s_exc_class: Exception, 
    t_exc_class: Type[TE], 
    mapper: ExceptionMapper[TE] = default_mapper
    ): ...

  sample.py:13:102 - error: Expression of type "(s_exc: Exception, t_exc_class: Type[TE@default_mapper]) -> TE@default_mapper" cannot be assigned to parameter of type "ExceptionMapper[TE@with_map_exceptions]"
    Parameter name mismatch: "source_exception" versus "s_exc"
    Function return type "TE@default_mapper" is incompatible with type "TE@with_map_exceptions"
      Type "Type[TE@default_mapper]" cannot be assigned to type "TE@default_mapper" (reportGeneralTypeIssues)

I'm not sure how to interpret the error message - I don't understand where Type[TE@default_mapper] is being assigned to TE@default_mapper.

This is with pyright@1.1.135.

Thanks for your help!

[erictraut]

This is a bug in the constraint solver. Thanks for the bug report. It will be fixed in the next release.