Update ModuleType to have __path__ optionally

[ewerybody]

Hello typeshed crew!
Analog to #6186 I'd like to add __path__ to ModuleType.

Custom packages always have this attribute and currently getting __path__ from these via sys.modules like for instance:

sys.modules['mymodule_pack'].__path__

results in typing complaints like

Cannot access member "__path__" for type "ModuleType"
  Member "__path__" is unknown

Since __file__ is already implemented. __path__ would also be good. Thanks.
ëRiC

[hauntsaninja]

Thanks, this should be a list. Also, under what circumstances is this ever None?

Actually looking closer, sometimes this can be at least a _NamespacePath (which is a MutableSequence).

[ewerybody]

... under what circumstances is this ever None?

Yeah arguable. In the other PR they were discussing about this because it may not exist at all which cannot be expressed. Or can it?

Actually looking closer, sometimes this can be at least a _NamespacePath (which is a MutableSequence).

Oh ok. Like option to list[str] | MutableSequence?
I coulnd't find _NamespacePath tho.

[ewerybody]

Thanks for reviewing! 🙏

[Akuli]

We don't have a way to express "__path__ may be missing", but I don't think it's a problem in practice:

• __file__ is missing in obscure corner cases. It would be good if the type checker warned about not checking that.
• __path__ is missing usually (specifically, for imported .py files). If you know anything at all about __path__, you are probably aware of this, or you will find out by doing some very basic testing, without checking corner cases.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

core (https://github.com/home-assistant/core.git)
+ homeassistant/loader.py:298: error: unused "type: ignore" comment

edgedb (https://github.com/edgedb/edgedb.git)
+ edb/schema/std.py:41: error: unused "type: ignore" comment
+ edb/schema/std.py:42: error: unused "type: ignore" comment
+ edb/schema/std.py:43: error: unused "type: ignore" comment
+ edb/schema/std.py:44: error: unused "type: ignore" comment

[Akuli]

Thanks!

[ewerybody]

a pleasure 🙇‍♀️