[Django] #34720: Path checking in BaseReloader.watch_dir() incorrectly checks for existence of path

[Django]

#34720: Path checking in BaseReloader.watch_dir() incorrectly checks for existence
of path
-----------------------------------------+------------------------
Reporter: Josh | Owner: nobody
Type: Bug | Status: new
Component: Uncategorized | Version: 4.2
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-----------------------------------------+------------------------
Within the `watch_dir` method in `django.utils.autoreload.BaseReloader`,
the path is checked by calling on the `absolute` method on the `Path`
object:

{{{
def watch_dir(self, path, glob):
path = Path(path)
try:
path = path.absolute()
except FileNotFoundError:
logger.debug(
"Unable to watch directory %s as it cannot be resolved.",
path,
exc_info=True,
)
return
logger.debug("Watching dir %s with glob %s.", path, glob)
self.directory_globs[path].add(glob)
}}}

Except `absolute` doesn't raise, it just returns the absolute path. Should
be changed to an if check on `path.exists()`:

{{{
Python 3.11.4 (main, Jul 17 2023, 15:40:49) [GCC 9.4.0]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.14.0 -- An enhanced Interactive Python. Type '?' for help.

In [1]: from pathlib import Path

In [2]: Path('/home/josh/projects/django/nonexistent').absolute()
Out[2]: PosixPath('/home/josh/projects/django/nonexistent')

In [3]: Path('/home/josh/projects/django/nonexistent').exists()
Out[3]: False
}}}

Willing to prepare a patch.

--
Ticket URL: <https://code.djangoproject.com/ticket/34720>
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