Make parameters order stable for multi-parameter URLs (#106)

Fixes #105

* Added intermittently failing test for #105
* Make parameter order stable for urls with multiple params

testproj/todo/urls.py

@@ -1,3 +1,4 @@
+from django.conf.urls import url
 from rest_framework import routers
 
 from todo import views
@@ -8,3 +9,8 @@ router.register(r'another', views.TodoAnotherViewSet)
 router.register(r'yetanother', views.TodoYetAnotherViewSet)
 
 urlpatterns = router.urls
+
+urlpatterns += [
+    url(r'^(?P<todo_id>\d+)/yetanother/(?P<yetanother_id>\d+)/$',
+        views.NestedTodoView.as_view(),),
+]

testproj/todo/views.py

@@ -1,4 +1,5 @@
 from rest_framework import viewsets
+from rest_framework.generics import RetrieveAPIView
 
 from .models import Todo, TodoAnother, TodoYetAnother
 from .serializer import TodoAnotherSerializer, TodoSerializer, TodoYetAnotherSerializer
@@ -20,3 +21,7 @@ class TodoAnotherViewSet(viewsets.ReadOnlyModelViewSet):
 class TodoYetAnotherViewSet(viewsets.ReadOnlyModelViewSet):
     queryset = TodoYetAnother.objects.all()
     serializer_class = TodoYetAnotherSerializer
+
+
+class NestedTodoView(RetrieveAPIView):
+    serializer_class = TodoYetAnotherSerializer