fix error when fetching on QuerySetWrapper

src/c3nav/editor/views.py

@@ -71,7 +71,7 @@ def level_detail(request, pk):
 @sidebar_view
 def space_detail(request, level, pk):
     Space = request.changeset.wrap('Space')
-    space = get_object_or_404(Space.objects.select_related('level'), level__id=level, pk=pk)
+    space = get_object_or_404(Space.objects.select_related('level'), level__pk=level, pk=pk)
 
     return render(request, 'editor/space.html', {
         'level': space.level,

src/c3nav/editor/wrappers.py

@@ -330,6 +330,8 @@ class BaseQueryWrapper(BaseWrapper):
             if filter_type == 'isnull':
                 return self._filter_values(q, field_name, lambda val: (val is None) is filter_value)
 
+            raise NotImplementedError
+
         if isinstance(class_value, DeferredAttribute):
             if not segments:
                 raise NotImplementedError