[1.3.X] Refs #15573, #15850: Added a check for whether the sites app …

…is installed when creating the test database, in order to work around a bug in get_model. Thanks to adsva and carljm.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.3.X@16062 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/backends/creation.py

@@ -379,9 +379,10 @@ def create_test_db(self, verbosity=1, autoclobber=False):
         # default site may or may not be 1, depending on how the sequence was
         # reset.  If the sites app is loaded, then we coerce it.
         from django.db.models import get_model
-        Site = get_model('sites', 'Site')
-        if Site is not None and Site.objects.using(self.connection.alias).count() == 1:
-            Site.objects.using(self.connection.alias).update(id=settings.SITE_ID)
+        if 'django.contrib.sites' in settings.INSTALLED_APPS:
+            Site = get_model('sites', 'Site')
+            if Site is not None and Site.objects.using(self.connection.alias).count() == 1:
+                Site.objects.using(self.connection.alias).update(id=settings.SITE_ID)
 
         from django.core.cache import get_cache
         from django.core.cache.backends.db import BaseDatabaseCache