Proper typing for run_sync method is now possible #197
Description
Is your feature request related to a problem? Please describe.
I authored sqlalchemy/sqlalchemy#5777 which added a typevar to run_sync to infer the return value. At that time is was not possible to infer *args or **kwargs of the callable passed and nor was it possible to infer that the first argument of type Session passed automatically for you. Since Python 3.10 has been released we have additional typing constructs typing.ParamSpec and typing.Concatenate, both of which are available on older python versions using the typing_extensions backport.
Describe the solution you'd like
Properly type all of the run_sync methods, something along the lines of the following should do the trick (I haven't set up an environment to test):
if sys.version_info >= (3, 10):
from typing import Concatenate
from typing import ParamSpec
else:
from typing_extensions import Concatenate
from typing_extensions import ParamSpec
_T = TypeVar("_T")
_P = ParamSpec("_P")
class AsyncSession(
_AsyncSessionTypingCommon,
_SessionInTransactionTypingCommon,
):
...
async def run_sync(
self,
fn: Callable[Concatenate[Session, _P], _T],
*arg: _P.args,
**kw: _P.kwargs,
) -> _T: ...Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
Additional context
Have a nice day!