id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
37067	"Deprecation warnings skip past packages named ""django_*"""	Mike Edmunds	Mike Edmunds	"The `django_file_prefixes()` utility doesn't include a trailing path separator, so also matches other packages whose installation directories start with ""django"". As a result, use of deprecated features in those packages will be mis-attributed to some other code outside those packages.

Django's implementation frequently has code like this:

{{{#!python
# django.some_module

import warnings
from django.utils.deprecation import RemovedInDjangoXXWarning, django_file_prefixes

def _some_helper():
    ...
    warnings.warn(
        ""This is deprecated."",
        RemovedInDjangoXXWarning,
        skip_file_prefixes=django_file_prefixes(),
    )

def some_django_feature():
    ...
    _some_helper()
    ...
}}}

The intent is a caller to `some_django_feature()` outside Django gets a deprecation warning pointed at their own code. (Not pointing at the call to `_some_helper()` in Django's implementation.)

As [https://github.com/django/django/blob/8ee73415270a1a54daaec9bb529ad82c6f7a6d4c/django/utils/deprecation.py#L13-L18 currently implemented], `django_file_prefixes()` returns the directory where Django is installed (in a tuple). E.g., `(""/venv/site-packages/django"",)`.

If `some_django_feature()` is called from a (hypothetical) `django_goodies` package installed in `/venv/site-packages/django_goodies/__init__.py`, the warning will skip it too: that filename [https://docs.python.org/3/library/stdtypes.html#str.startswith startswith] the django_file_prefixes. The resulting warning will point to the first stack frame outside `django_goodies`, which may be completely disconnected from the deprecated feature usage."	Bug	assigned	Utilities	6.0	Normal				Unreviewed	0	0	0	0	0	0