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
7967	"cache.has_key() doesn't do the same thing as ""key in cache"""	Marty Alchin	Marty Alchin	"In [source:django/trunk/django/core/cache/backends/base.py django.core.cache.backends.base.BaseCache], `has_key()` is defined as a method, while `__contains__` is simply an alias for it. Individual backends override `has_key()` to be more efficient, but `__contains__` is left alone, so it's still an alias for the base function, which unfortunately means that the two end up with different implementations. This is generally fine, but shows itself when `None` is stored in the cache, which is a potentially useful situation.

{{{
#!python
>>> from django.core.cache import cache
>>> cache.set('test', None)
>>> cache.has_key('test')
True
>>> 'test' in cache
False
}}}"		closed	Core (Other)	dev		fixed			Unreviewed	1	0	0	0	0	0