From b105731ada4ef3e148e43feec4549ab2bdac5a61 Mon Sep 17 00:00:00 2001
From: Mateusz Bocian <mbocian@waveapps.com>
Date: Mon, 2 Oct 2017 17:33:38 -0400
Subject: [PATCH] Patching private variables

---
 graphene/types/tests/test_objecttype.py |  2 +-
 graphene/types/tests/test_query.py      | 23 +++++++++++++++++++++--
 graphene/types/utils.py                 |  2 ++
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/graphene/types/tests/test_objecttype.py b/graphene/types/tests/test_objecttype.py
index 5ff972de..c6e1db53 100644
--- a/graphene/types/tests/test_objecttype.py
+++ b/graphene/types/tests/test_objecttype.py
@@ -65,7 +65,7 @@ def test_generate_objecttype_with_fields():
 
 def test_generate_objecttype_with_private_attributes():
     class MyObjectType(ObjectType):
-        _private_state = None
+        _private_state = Field(MyType)
 
     assert '_private_state' not in MyObjectType._meta.fields
     assert hasattr(MyObjectType, '_private_state')
diff --git a/graphene/types/tests/test_query.py b/graphene/types/tests/test_query.py
index 95e626ef..3f6f578c 100644
--- a/graphene/types/tests/test_query.py
+++ b/graphene/types/tests/test_query.py
@@ -297,6 +297,27 @@ def test_query_middlewares():
     assert executed.data == {'hello': 'dlroW', 'other': 'rehto'}
 
 
+def test_query_private_values():
+    class MyType(ObjectType):
+        _private = String()
+        public = String()
+
+    class Query(ObjectType):
+        field = Field(MyType)
+
+    hello_schema = Schema(Query)
+
+    executed = hello_schema.execute('{ field { Private } }')
+    assert executed.errors
+
+    executed = hello_schema.execute('{ field { _private } }')
+    assert executed.errors
+
+    executed = hello_schema.execute('{ field { public } }')
+    assert not executed.errors
+    assert executed.data == {'field': None}
+
+
 def test_objecttype_on_instances():
     class Ship:
 
@@ -442,8 +463,6 @@ def test_big_list_of_containers_multiple_fields_custom_resolvers_query_benchmark
 
 
 def test_query_annotated_resolvers():
-    import json
-
     context = Context(key="context")
 
     class Query(ObjectType):
diff --git a/graphene/types/utils.py b/graphene/types/utils.py
index c4434199..0df0e7a0 100644
--- a/graphene/types/utils.py
+++ b/graphene/types/utils.py
@@ -28,6 +28,8 @@ def yank_fields_from_attrs(attrs, _as=None, sort=True):
     '''
     fields_with_names = []
     for attname, value in list(attrs.items()):
+        if attname.startswith('_'):
+            continue
         field = get_field_as(value, _as)
         if not field:
             continue