diff --git a/tests/defaultfilters/tests.py b/tests/defaultfilters/tests.py
index a97929859e..d0009c6e66 100644
--- a/tests/defaultfilters/tests.py
+++ b/tests/defaultfilters/tests.py
@@ -11,6 +11,8 @@ from django.utils import unittest, translation
 from django.utils.safestring import SafeData
 from django.utils.encoding import python_2_unicode_compatible
 
+from i18n import TransRealMixin
+
 
 class DefaultFiltersTests(TestCase):
 
@@ -594,28 +596,6 @@ class DefaultFiltersTests(TestCase):
         self.assertEqual(filesizeformat("\N{GREEK SMALL LETTER ALPHA}"),
                           '0\xa0bytes')
 
-    def test_localized_filesizeformat(self):
-        # NOTE: \xa0 avoids wrapping between value and unit
-        with self.settings(USE_L10N=True):
-            with translation.override('de', deactivate=True):
-                self.assertEqual(filesizeformat(1023), '1023\xa0Bytes')
-                self.assertEqual(filesizeformat(1024), '1,0\xa0KB')
-                self.assertEqual(filesizeformat(10*1024), '10,0\xa0KB')
-                self.assertEqual(filesizeformat(1024*1024-1), '1024,0\xa0KB')
-                self.assertEqual(filesizeformat(1024*1024), '1,0\xa0MB')
-                self.assertEqual(filesizeformat(1024*1024*50), '50,0\xa0MB')
-                self.assertEqual(filesizeformat(1024*1024*1024-1), '1024,0\xa0MB')
-                self.assertEqual(filesizeformat(1024*1024*1024), '1,0\xa0GB')
-                self.assertEqual(filesizeformat(1024*1024*1024*1024), '1,0\xa0TB')
-                self.assertEqual(filesizeformat(1024*1024*1024*1024*1024),
-                                  '1,0\xa0PB')
-                self.assertEqual(filesizeformat(1024*1024*1024*1024*1024*2000),
-                                  '2000,0\xa0PB')
-                self.assertEqual(filesizeformat(complex(1,-1)), '0\xa0Bytes')
-                self.assertEqual(filesizeformat(""), '0\xa0Bytes')
-                self.assertEqual(filesizeformat("\N{GREEK SMALL LETTER ALPHA}"),
-                                  '0\xa0Bytes')
-
     def test_pluralize(self):
         self.assertEqual(pluralize(1), '')
         self.assertEqual(pluralize(0), 's')
@@ -660,3 +640,27 @@ class DefaultFiltersTests(TestCase):
         self.assertEqual(removetags(123, 'a'), '123')
         self.assertEqual(striptags(123), '123')
 
+
+class DefaultFiltersI18NTests(TransRealMixin, TestCase):
+
+    def test_localized_filesizeformat(self):
+        # NOTE: \xa0 avoids wrapping between value and unit
+        with self.settings(USE_L10N=True):
+            with translation.override('de', deactivate=True):
+                self.assertEqual(filesizeformat(1023), '1023\xa0Bytes')
+                self.assertEqual(filesizeformat(1024), '1,0\xa0KB')
+                self.assertEqual(filesizeformat(10*1024), '10,0\xa0KB')
+                self.assertEqual(filesizeformat(1024*1024-1), '1024,0\xa0KB')
+                self.assertEqual(filesizeformat(1024*1024), '1,0\xa0MB')
+                self.assertEqual(filesizeformat(1024*1024*50), '50,0\xa0MB')
+                self.assertEqual(filesizeformat(1024*1024*1024-1), '1024,0\xa0MB')
+                self.assertEqual(filesizeformat(1024*1024*1024), '1,0\xa0GB')
+                self.assertEqual(filesizeformat(1024*1024*1024*1024), '1,0\xa0TB')
+                self.assertEqual(filesizeformat(1024*1024*1024*1024*1024),
+                                  '1,0\xa0PB')
+                self.assertEqual(filesizeformat(1024*1024*1024*1024*1024*2000),
+                                  '2000,0\xa0PB')
+                self.assertEqual(filesizeformat(complex(1,-1)), '0\xa0Bytes')
+                self.assertEqual(filesizeformat(""), '0\xa0Bytes')
+                self.assertEqual(filesizeformat("\N{GREEK SMALL LETTER ALPHA}"),
+                                  '0\xa0Bytes')