django_file_prefixes() raises TypeError if Django is imported by namespace

[Jacob Walls]

cd one level above your django checkout, and launch a python shell.

Calling django_file_prefixes will fail:

>>> import django
>>> django.__file__ is None
True
>>> from django.utils.deprecation import django_file_prefixes
>>> django_file_prefixes()
Traceback (most recent call last):
  File "<python-input-1>", line 5, in <module>
    django_file_prefixes()
    ~~~~~~~~~~~~~~~~~~~~^^
  File "/Users/jwalls/django/django/utils/deprecation.py", line 18, in django_file_prefixes
    return (os.path.dirname(file),)
            ~~~~~~~~~~~~~~~^^^^^^
  File "<frozen posixpath>", line 178, in dirname
TypeError: expected str, bytes or os.PathLike object, not NoneType

---

How I found this was by testing deprecation warnings, so what I'm concluding is that deprecation warnings might crash in 6.0 if you import Django by namespace.

[Jacob Walls]

​PR