Add datetime.date and datetime.datetime specializations

[alippai]

• Closes BDay typing #755
• Tests added:

[twoertwein]

Can you please add runtime tests in https://github.com/pandas-dev/pandas-stubs/blob/main/tests/test_timefuncs.py

You will also need to re-order the overloads to have the more specifiy overloads before more general overloads as type checker pick the first fitting overload (see the mypy errors).

[alippai]

@twoertwein thanks, I've updated the failing test and added the two cases brought up in the initial issue. Looks like datetime is a subclass of date so I just removed that, it could fix the overloads.

[Dr-Irv]

Your tests are still failing. I think the issue here is that this line is incorrect in offsets.pyi:

_DatetimeT = TypeVar("_DatetimeT", bound=date)

I think it should be

_DatetimeT = TypeVar("_DatetimeT", bound=datetime)

based on what is now in the pandas source.

Can you try that change to see if it will make things work? Because the error you are getting is that this overload: def __add__(self, other: _DatetimeT) -> _DatetimeT: ... will never get matched, because you put in something explicit for date, but datetime is a subclass of date, so I think changing the TypeVar line will fix it.

[alippai]

Looks like this is not possible to describe correctly: microsoft/pylance-release#6512

[Dr-Irv]

Looks like this is not possible to describe correctly: microsoft/pylance-release#6512

I'm OK with putting in the appropriate #type: ignore and #pyright: ignore statements when the type checkers are reporting overlapping overloads.

[alippai]

@Dr-Irv thanks for the guide, I believe the last commit may work as intended and pass the CI