[django/django] 1be03a: Fixed #18389 -- Fixed the way contribute_to_class ...

[GitHub]

Branch: refs/heads/master
Home: https://github.com/django/django
Commit: 1be03aff5c24e902b89503dda32891aa4881579e
https://github.com/django/django/commit/1be03aff5c24e902b89503dda32891aa4881579e
Author: Vlad Starostin <drt...@yandex.ru>
Date: 2014-05-16 (Fri, 16 May 2014)

Changed paths:
M django/db/models/base.py
M tests/model_fields/models.py

Log Message:
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Fixed #18389 -- Fixed the way contribute_to_class is called

Now this method is only called only if the object is an instance.
This allows to have field classes as model class attributes.