os.open() can take Path objects in Python 3.6

[toolness]

I noticed that the following code fails when checked by mypy under Python 3.6:

import os
from pathlib import Path

fd = os.open(Path('/dev/null'), os.O_RDONLY)

The following error is produced:

error: Type argument 1 of "open" has incompatible value "Path"

However, the code seems to work fine due to Python 3.6's support for PEP 519.

If this is a problem with the type stubs then I could try submitting a PR. mypy rocks!

[JelleZijlstra]

Yes, this is a problem with the stubs. There's an open PR to fix a few other functions in a similar way at #991, but we need to change a lot more functions.

[JelleZijlstra]

os.open is now declared as taking _PathType, which includes PathLike in 3.6+.