Fixed #27402 -- Fixed incorrect LocaleMiddleware redirects with prefix_default_language=False.

tests/i18n/tests.py

@@ -1860,6 +1860,20 @@ class UnprefixedDefaultLanguageTests(SimpleTestCase):
         response = self.client.get('/de-simple-page/')
         self.assertEqual(response.content, b'Yes')
 
+    def test_no_redirect_on_404(self):
+        """
+        A request for a nonexistent URL shouldn't cause a redirect to
+        /<defaut_language>/<request_url> when prefix_default_language=False and
+        /<default_language>/<request_url> has a URL match (#27402).
+        """
+        # A match for /group1/group2/ must exist for this to act as a
+        # regression test.
+        response = self.client.get('/group1/group2/')
+        self.assertEqual(response.status_code, 200)
+
+        response = self.client.get('/nonexistent/')
+        self.assertEqual(response.status_code, 404)
+
 
 @override_settings(
     USE_I18N=True,

tests/i18n/urls_default_unprefixed.py

@@ -6,5 +6,6 @@ from django.utils.translation import ugettext_lazy as _
 urlpatterns = i18n_patterns(
     url(r'^(?P<arg>[\w-]+)-page', lambda request, **arg: HttpResponse(_("Yes"))),
     url(r'^simple/$', lambda r: HttpResponse(_("Yes"))),
+    url(r'^(.+)/(.+)/$', lambda *args: HttpResponse()),
     prefix_default_language=False,
 )