Fixes nested node test when django-filter is not installed.

Author: Pablo Chinea

graphene_django/tests/test_query.py

@@ -8,6 +8,7 @@
 import graphene
 from graphene.relay import Node
 
+from ..utils import DJANGO_FILTER_INSTALLED
 from ..compat import MissingType, RangeField
 from ..fields import DjangoConnectionField
 from ..types import DjangoObjectType
@@ -282,6 +283,9 @@ def resolve_all_reporters(self, args, context, info):
         }
     }
 
+
+@pytest.mark.skipif(not DJANGO_FILTER_INSTALLED,
+                    reason="django-filter should be installed")
 def test_should_query_node_filtering():
     class ReporterType(DjangoObjectType):
 
@@ -320,7 +324,6 @@ class Query(graphene.ObjectType):
         lang='en'
     )
 
-
     schema = graphene.Schema(query=Query)
     query = '''
         query NodeFilteringQuery {