Signature incompatible with supertype when using static methods

[barisione]

This code:

class Base:
    @staticmethod
    def method(n: int) -> None:
        print(n)


class Deriv(Base):
    def method(self, n: int) -> None:
        print(f"{n} from {self}")

Produces this:

$ mypy test_static.py
test_static.py:8: error: Signature of "method" incompatible with supertype "Base"
Found 1 error in 1 file (checked 1 source file)

When using mypy from git (mypy 0.790+dev.c231ee4fdca075582e1177a8ecea3f379ccaa784) with Python 3.8.

This is pretty similar to #4125 (attributes overwritten with properties) and could end up being fixed by #7724.
I'm still reporting the issue as I didn't see any mention of static methods in other issues.

[ilevkivskyi]

FWIW mypy is correct here, this is not a safe override, since methods can be called on class objects:

x: Type[Base] = Deriv
x.method(42) # Oops, TypeError at runtime here

[i386x]

On the other hand, this clashes with pylint: R0201: Method could be a function (no-self-use)