Unbound method rejected as FunctionType, Callable cast as FunctionType

[tlambert03]

Bug Report

This feels related to #8869, but different enough to warrant a separate issue.
There, the issue was that a bound method of MethodType is incorrectly rejected as a Callable, here, I'm noticing that an unbound class method is rejected as a FunctionType:

To Reproduce

import types

class Cls:
    def meth(self):
        pass

assert isinstance(Cls.meth, types.FunctionType)  # no problem

x: types.FunctionType = Cls.meth

Incompatible types in assignment (expression has type "Callable[[Cls], Any]", variable has type "FunctionType")  [assignment]

Expected Behavior

I expected an unbound class method to work for an argument expecting FunctionType

Actual Behavior

Incompatible types in assignment

Your Environment

• mypy 0.790
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: 3.8.6
• Operating system and version: macos 10.15.7

Additional info

(In this case, I didn't want to use x: Callable because I'd like to be able to assert that the standard function object methods will be available)

[tlambert03]

Actually, I guess I'm realizing that mypy more generally interprets Callable as having many of the attributes of a typical FunctionType ... though this may not always be the case. For example. The following code will fail at runtime with AttributeError: 'Cls' object has no attribute '__name__', but mypy has no problem with it:

from typing import Callable

def w(f: Callable):
    print(f.__name__)

class Cls:
    def __call__(self) -> None:
        pass

w(Cls())

[erictraut]

This bug appears to have been fixed. I can no longer repro the problem with the latest version of mypy (1.5).