Fixed #13389 -- Ensured that the app_loading test clears out the app cache at the end of each test, so that it doesn't interact badly with flush and other introspected database commands. Thanks to Karen for the report, and Ramiro Morales for the debugging hints.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13011 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/app_loading/tests.py

@@ -1,10 +1,11 @@
+import copy
 import os
 import sys
 import time
 from unittest import TestCase
 
 from django.conf import Settings
-from django.db.models.loading import load_app
+from django.db.models.loading import cache, load_app
 
 __test__ = {"API_TESTS": """
 Test the globbing of INSTALLED_APPS.
@@ -33,8 +34,16 @@ class EggLoadingTest(TestCase):
         self.old_path = sys.path
         self.egg_dir = '%s/eggs' % os.path.dirname(__file__)
 
+        # This test adds dummy applications to the app cache. These
+        # need to be removed in order to prevent bad interactions
+        # with the flush operation in other tests.
+        self.old_app_models = copy.deepcopy(cache.app_models)
+        self.old_app_store = copy.deepcopy(cache.app_store)
+
     def tearDown(self):
         sys.path = self.old_path
+        cache.app_models = self.old_app_models
+        cache.app_store = self.old_app_store
 
     def test_egg1(self):
         """Models module can be loaded from an app in an egg"""
@@ -63,7 +72,7 @@ class EggLoadingTest(TestCase):
         sys.path.append(egg_name)
         models = load_app('omelet.app_no_models')
         self.failUnless(models is None)
- 
+
     def test_egg5(self):
         """Loading an app from an egg that has an import error in its models module raises that error"""
         egg_name = '%s/brokenapp.egg' % self.egg_dir