Opened 14 years ago
Last modified 13 years ago
#14698 closed
django.utils.module_loading.module_has_submodule yields false positives — at Initial Version
| Reported by: | Łukasz Rekucki | Owned by: | nobody |
|---|---|---|---|
| Component: | Core (Other) | Version: | 1.2 |
| Severity: | Keywords: | ||
| Cc: | Michael Shields | Triage Stage: | Ready for checkin |
| Has patch: | yes | Needs documentation: | no |
| Needs tests: | no | Patch needs improvement: | no |
| Easy pickings: | no | UI/UX: | no |
Description
The way I found this is a bit crazy, so I'm not going to describe it all, but the 2 important things are:
# I have some explicit relative imports.
# I wanted to make a template library named the same as the application it contains.
This generally should work (tried on a fresh project), but failed with a weird error in my project: "'currencies' is not a valid tag library: ImportError raised loading company.templatetags.currencies: No module named currencies". Of course there is no such module, because it's on "currencies.templatags" application.
So after some debuging it turned out that module_has_submodule returns a false positive. This is because it checks if name in sys.modules . To be honest, I didn't know about this, but it seems that Python sometimes also stores import misses by puting a None in to that dictionary. See this python-dev thread.