pathlib.Path property access is considered a Callable

[thomascellerier]

Using mypy 0.4.6.

repro.py:

import pathlib

file_dir = pathlib.Path(__file__).parent

def some_file() -> pathlib.Path:
    return file_dir / 'foo.txt'

if __name__ == '__main__':
     print(str(some_file()))

output:

$ python3 repro.py 
foo.txt
$ mypy repro.py 
repro.py: note: In function "some_file":
repro.py:8: error: Unsupported left operand type for / (Callable[[], Path])

[thomascellerier]

Weirdly enough the error is different if I am in a virtualenv or not:

$ python3 -m venv virtualenv
$ ./virtualenv/bin/pip3 install mypy-lang==0.4.6
$ ./virtualenv/bin/mypy repro.py 
repro.py: note: In function "some_file":
repro.py:8: error: Unsupported left operand type for / (Callable[[], Path])

$ pip3 install --user --upgrade mypy-lang==0.4.6
$ mypy repro.py 
repro.py: note: In function "some_file":
repro.py:8: error: Incompatible return value type (got "PurePath", expected "Path")

[rwbarton]

This is a typeshed issue (I filed python/typeshed#701). The reason you're seeing different behaviors is due to some recent typeshed commits affecting the stubs for pathlib.