Added django.utils.translation.override context manager to easily activate and deactivate a language for a code block.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16166 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/i18n/tests.py

@@ -8,6 +8,7 @@ from threading import local
 
 from django.conf import settings
 from django.template import Template, Context
+from django.test import TestCase
 from django.utils.formats import (get_format, date_format, time_format,
     localize, localize_input, iter_format_modules, get_format_modules)
 from django.utils.importlib import import_module
@@ -28,6 +29,13 @@ from test_warnings import DeprecationWarningTests
 
 class TranslationTests(TestCase):
 
+    def test_override(self):
+        activate('de')
+        with translation.override('pl'):
+            self.assertEqual(get_language(), 'pl')
+        self.assertEqual(get_language(), 'de')
+        deactivate()
+
     def test_lazy_objects(self):
         """
         Format string interpolation should work with *_lazy objects.