From 9be01a6e4d0d9fda1560b064aaafe217970c015b Mon Sep 17 00:00:00 2001
From: Carlton Gibson <carlton.gibson@noumenal.co.uk>
Date: Mon, 7 Apr 2014 19:51:37 +0200
Subject: [PATCH] Reverse order to checks in reverse.

Add namespace then fallback to non-namespaced to allow reversing of non-namespaced views from namespaced request
---
 rest_framework/reverse.py            | 32 +++++++++++++++++-----------
 rest_framework/tests/test_reverse.py |  7 ++++++
 2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/rest_framework/reverse.py b/rest_framework/reverse.py
index d4240533b..5d21d55c6 100644
--- a/rest_framework/reverse.py
+++ b/rest_framework/reverse.py
@@ -2,7 +2,7 @@
 Provide reverse functions that return fully qualified URLs
 """
 from __future__ import unicode_literals
-from django.core.urlresolvers import reverse as django_reverse
+from django.core.urlresolvers import reverse as django_reverse, NoReverseMatch
 from django.utils.functional import lazy
 from django.core.urlresolvers import resolve
 from django.http import Http404
@@ -18,21 +18,27 @@ def reverse(viewname, args=None, kwargs=None, request=None, format=None, **extra
         kwargs = kwargs or {}
         kwargs['format'] = format
 
-    if request:
-        try:
-            namespace = request.resolver_match.namespace
-        except AttributeError:
+    try:
+        viewname_to_try = viewname
+        if request:
             try:
-                namespace = resolve(request.path).namespace
-            except Http404:
-                namespace=None
+                namespace = request.resolver_match.namespace
+            except AttributeError:
+                try:
+                    namespace = resolve(request.path).namespace
+                except Http404:
+                    namespace=None
 
-        if namespace and ':' not in viewname:
-            viewname = '{namespace}:{viewname}'.format(namespace=namespace,
-                                                   viewname=viewname)
+            if namespace and ':' not in viewname:
+                viewname_to_try = '{namespace}:{viewname}'.format(namespace=namespace,
+                                                       viewname=viewname)
+
+        url = django_reverse(viewname_to_try, args=args, kwargs=kwargs,
+                              **extra)
+    except NoReverseMatch:
+        url = django_reverse(viewname, args=args, kwargs=kwargs,
+                              **extra)
 
-    url = django_reverse(viewname, args=args, kwargs=kwargs,
-                          **extra)
     if request:
         return request.build_absolute_uri(url)
 
diff --git a/rest_framework/tests/test_reverse.py b/rest_framework/tests/test_reverse.py
index 1bb7882cb..f63e4ff1e 100644
--- a/rest_framework/tests/test_reverse.py
+++ b/rest_framework/tests/test_reverse.py
@@ -13,6 +13,7 @@ def null_view(request):
 
 v0_urlpatterns = patterns('',
     url(r'^view$', null_view, name='view'),
+    url(r'^other-view', null_view, name="other-view"),
 )
 
 v1_urlpatterns = patterns('',
@@ -52,6 +53,12 @@ class ReverseTests(TestCase):
         url = reverse('view', request=request)
         self.assertEqual(url, 'http://testserver/v2/view')
 
+    def test_namespaced_request_to_non_namespaced_view_not_in_namespace(self):
+        request = factory.get('/v2/view')
+        url = reverse('other-view', request=request)
+        self.assertEqual(url, 'http://testserver/other-view')
+
+
     # Additional tests for #1143
     # Covering cases mentioned
     # https://github.com/tomchristie/django-rest-framework/pull/1143#issuecomment-30031591