Bug: Incorrect typing in SQLAlchemyAsyncRepositoryReadService

[vikigenius]

Description

class SQLAlchemyAsyncRepositoryReadService(Generic[ModelT], ResultConverter):
    """Service object that operates on a repository object."""

    repository_type: type[SQLAlchemyAsyncRepositoryProtocol[ModelT] | SQLAlchemyAsyncSlugRepositoryProtocol[ModelT]]

Firstly repository_type is uninitialized. This automatically raises an issue if strict.

But more importantly when you do something like this: Which happens in the litestar fullstack example

class UserService(SQLAlchemyAsyncRepositoryService[User]):
    """Handles database operations for users."""

    repository_type = UserRepository

And then try to do

self.repository: UserRepository = self.repository_type(**repo_kwargs)

Typechecker complains that Type "SQLAlchemyAsyncRepositoryProtocol[User] | SQLAlchemyAsyncSlugRepositoryProtocol[User]" is not assignable to type "UserRepository"

URL to code causing the issue

No response

MCVE

This is easier to see with a completely synthetic example

class ClassA:
    """Class A."""

class ClassB:
    """Class B."""


class ClassSA(ClassA):
    """Class SA"""

class ClassR:
    """Class R."""
    ctype: type[ClassA] | type[ClassB] = ClassA


class ClassSAR(ClassR):
    ctype = ClassSA

    def __init__(self) -> None:
        super().__init__()
        self.c: ClassSA = self.ctype()

The type checker complains that Type "ClassA | ClassB" is not assignable to type "ClassSA"

This might be a bug in pyright. But I think the behavior does make sense because at runtime ctype() could still return ClassB. So a Cast is needed

Steps to reproduce

Run the MCVE

Screenshots

"In the format of: ![SCREENSHOT_DESCRIPTION](SCREENSHOT_LINK.png)"

Logs

No response

Package Version

0.20.0

Platform

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• Mac
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