[1.1.X] Changed setUp and tearDown for the tests converted from doctests in r11695

to not assume TZ absolutely will be set in the environment. That environment
variable does not necessarily exist on Windows, it seems. 

r11699 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@11700 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/utils/dateformat.py

@@ -6,11 +6,14 @@ from django.utils.tzinfo import FixedOffset, LocalTimezone
 
 class DateFormatTests(TestCase):
     def setUp(self):
-        self.old_TZ = os.environ['TZ']
+        self.old_TZ = os.environ.get('TZ')
         os.environ['TZ'] = 'Europe/Copenhagen'
 
     def tearDown(self):
-        os.environ['TZ'] = self.old_TZ
+        if self.old_TZ is None:
+            del os.environ['TZ']
+        else:
+            os.environ['TZ'] = self.old_TZ
 
     def test_date(self):
         d = date(2009, 5, 16)