fixtures are imported twice with duplicate FIXTURE_DIRS

[karyon]

when listing a fixture dir two times in FIXTURE_DIRS, or listing a directory there that is already a default fixture dir of an app, fixtures in these directories are imported twice when running loaddata.

in my project someone accidentally added a default fixture dir to the FIXTURE_DIRS, and it took us a while to figure out why things were imported twice.

on a side node, if fixtures of the same name are in different directories, there are all imported, as opposed to when they are in the same directory (with different extensions). is this intended?

[Aymeric Augustin]

In this situation, Django could raise an ImproperlyConfigured exception, emit a warning (maybe with a check?), or at least deduplicate the list. Loading the fixture twice doesn't make sense.

Regarding your second question, yes, this is the intended behavior.

[Konrad Świat]

Work in progress:
​https://github.com/kswiat/django/commit/0b96027f697c173f860be2cef18451a715dbe7f1

But I will probably move it to the check framework, because apps are not ready at this point (loading settings). Apps need to be registered in order to get their labels (please correct me if I'm wrong and there is other clean way to do it).

EDIT:
Check framework based version:
​https://github.com/kswiat/django/commit/506391bf1295f6fcd31a74a345fa210a224705e7

[Konrad Świat]

Pull request ready.

[Claude Paroz]

Wouldn't it be better to check this in the loaddata fixture_dirs method?

[Konrad Świat]

There is new PR with different approach, that checks settings.FIXTURE_DIRS in the loaddata fixture_dirs method. If there are duplications or default fixture dir of an app, exception is raised.
​​https://github.com/django/django/pull/3447
Or maybe it should emit a warning instead of raising?

[Konrad Świat]

I added release notes for 1.7.2, 1.8 and improved patch.

[Tim Graham <timograham@…>]

In 934a16dc93a5f46f965ba299dbd543703d32d493:

Fixed #23468 -- Added checks for duplicate fixtures directories in loaddata.

If settings.FIXTURE_DIRS contains duplicates or a default fixture
directory (app_name/fixtures), ImproperlyConfigured is raised.

Thanks to Berker Peksag and Tim Graham for review.