Fixed #18700 -- Added URL reversal for i18n set_language view.

django/conf/urls/i18n.py

@@ -1,5 +1,5 @@
 from django.conf import settings
-from django.conf.urls import patterns
+from django.conf.urls import patterns, url
 from django.core.urlresolvers import LocaleRegexURLResolver
 
 def i18n_patterns(prefix, *args):
@@ -16,5 +16,5 @@ def i18n_patterns(prefix, *args):
 
 
 urlpatterns = patterns('',
-    (r'^setlang/$', 'django.views.i18n.set_language'),
+    url(r'^setlang/$', 'django.views.i18n.set_language', name='set_language'),
 )

docs/topics/i18n/translation.txt

@@ -1272,7 +1272,7 @@ Here's example HTML template code:
 
 .. code-block:: html+django
 
-    <form action="/i18n/setlang/" method="post">
+    <form action="{% url 'set_language' %}" method="post">
     {% csrf_token %}
     <input name="next" type="hidden" value="{{ redirect_to }}" />
     <select name="language">

tests/regressiontests/views/tests/i18n.py

@@ -5,6 +5,7 @@ import gettext
 from os import path
 
 from django.conf import settings
+from django.core.urlresolvers import reverse
 from django.test import TestCase
 from django.utils.translation import override, activate, get_language
 from django.utils.text import javascript_quote
@@ -23,6 +24,9 @@ class I18NTests(TestCase):
             self.assertRedirects(response, 'http://testserver/views/')
             self.assertEqual(self.client.session['django_language'], lang_code)
 
+    def test_setlang_reversal(self):
+        self.assertEqual(reverse('set_language'), '/views/i18n/setlang/')
+
     def test_jsi18n(self):
         """The javascript_catalog can be deployed with language settings"""
         saved_lang = get_language()