Does this new way of ignoring mypy-only errors allow enabling mypy's and pyright's check for unneeded ignores?

For mypy, the answer is no. See python/mypy#14365

I wanted to add a test like this:

if TYPE_CHECKING_INVALID_USAGE and not IS_TYPE_CHECKER_MYPY:
     df.columns = "abc"  # type: ignore[assignment]

but mypy still checks it. Although I guess I could use a pyright: ignore here and do that. I will try that out.

Could do something like at typeshed python/typeshed@23ac9bf Use type: ignore for only mypy and the pyright-specific codes only for pyright. I think this could be cleaner than the constant approach.

Could do something like at typeshed python/typeshed@23ac9bf Use type: ignore for only mypy and the pyright-specific codes only for pyright. I think this could be cleaner than the constant approach.

We currently are reporting wrong ignores with mypy. But for pyright, if we use the option reportUnnecessaryTypeIgnoreComment, we get a lot of reports. The reason is that in the PYI files, we have # type: ignore comments that are needed for mypy, but not for pyright. So the typeshed solution won't help here - we can't put something that says "ignore for mypy, but pyright should type check"

If we have a line of valid code, then I think this table summarizes things

It's the third case that is causing issues for us to be able to use reportUnnecessaryTypeIgnoreComment with pyright

So there isn't a Mypy-only equivalent of #pyright: ignore (or a way to have Pyright disregard type: ignore)? I feel like the optimal solution would be to require separate ignores for Mypy and Pyright individually, but from the table it doesn't seem like that's even possible.

So there isn't a Mypy-only equivalent of #pyright: ignore (or a way to have Pyright disregard type: ignore)? I feel like the optimal solution would be to require separate ignores for Mypy and Pyright individually, but from the table it doesn't seem like that's even possible.

Unforunately, there is not a #mypy: ignore and there is a feature request here for that: python/mypy#12358