From a01d887a3ad9029ed198b6af974534fec46223f9 Mon Sep 17 00:00:00 2001
From: Krzysztof Urbaniak <urban@fail.pl>
Date: Fri, 28 Oct 2016 11:36:53 +0200
Subject: [PATCH] Fixed #27063 -- Prevented i18n_patterns() from using too much
 of the URL as the language.

---
 django/utils/translation/trans_real.py | 2 +-
 docs/releases/1.10.3.txt               | 3 +++
 tests/i18n/tests.py                    | 7 +++++++
 tests/i18n/urls_default_unprefixed.py  | 1 +
 4 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/django/utils/translation/trans_real.py b/django/utils/translation/trans_real.py
index 06331a502f..84a42490eb 100644
--- a/django/utils/translation/trans_real.py
+++ b/django/utils/translation/trans_real.py
@@ -45,7 +45,7 @@ language_code_re = re.compile(
     re.IGNORECASE
 )
 
-language_code_prefix_re = re.compile(r'^/([\w@-]+)(/|$)')
+language_code_prefix_re = re.compile(r'^/(\w+([@-]\w+)?)(/|$)')
 
 
 @receiver(setting_changed)
diff --git a/docs/releases/1.10.3.txt b/docs/releases/1.10.3.txt
index 5bb340a3a8..ba01287aa5 100644
--- a/docs/releases/1.10.3.txt
+++ b/docs/releases/1.10.3.txt
@@ -23,3 +23,6 @@ Bugfixes
 
 * Fixed ``QuerySet.bulk_create()`` on PostgreSQL when the number of objects is
   a multiple plus one of ``batch_size`` (:ticket:`27385`).
+
+* Prevented ``i18n_patterns()`` from using too much of the URL as the language
+  to fix a use case for ``prefix_default_language=False`` (:ticket:`27063`).
diff --git a/tests/i18n/tests.py b/tests/i18n/tests.py
index 1e49565a8c..daba0d34a7 100644
--- a/tests/i18n/tests.py
+++ b/tests/i18n/tests.py
@@ -1490,6 +1490,7 @@ class MiscTests(SimpleTestCase):
         self.assertEqual(g('/de/'), 'de')
         self.assertEqual(g('/de-at/'), 'de-at')
         self.assertEqual(g('/de-ch/'), 'de')
+        self.assertIsNone(g('/de-simple-page/'))
 
     def test_get_language_from_path_null(self):
         from django.utils.translation.trans_null import get_language_from_path as g
@@ -1822,6 +1823,7 @@ class LocaleMiddlewareTests(TestCase):
     USE_I18N=True,
     LANGUAGES=[
         ('en', 'English'),
+        ('de', 'German'),
         ('fr', 'French'),
     ],
     MIDDLEWARE=[
@@ -1852,6 +1854,11 @@ class UnprefixedDefaultLanguageTests(SimpleTestCase):
         with self.assertRaisesMessage(AssertionError, "Unexpected kwargs for i18n_patterns(): {'foo':"):
             i18n_patterns(object(), foo='bar')
 
+    def test_page_with_dash(self):
+        # A page starting with /de* shouldn't match the 'de' langauge code.
+        response = self.client.get('/de-simple-page/')
+        self.assertEqual(response.content, b'Yes')
+
 
 @override_settings(
     USE_I18N=True,
diff --git a/tests/i18n/urls_default_unprefixed.py b/tests/i18n/urls_default_unprefixed.py
index 8cadbfaa73..92ef8c6246 100644
--- a/tests/i18n/urls_default_unprefixed.py
+++ b/tests/i18n/urls_default_unprefixed.py
@@ -4,6 +4,7 @@ from django.http import HttpResponse
 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"))),
     prefix_default_language=False,
 )