Added tests.

graphene/relay/node.py

@@ -47,7 +47,7 @@ class GlobalID(Field):
         return node.to_global_id(parent_type_name, type_id)  # root._meta.name
 
     def get_resolver(self, parent_resolver):
-        return partial(self.id_resolver, parent_resolver, self.node, parent_type_name=self._parent_type_name)
+        return partial(self.id_resolver, parent_resolver, self.node, parent_type_name=self.parent_type_name)
 
 
 class NodeMeta(InterfaceMeta):

graphene/relay/tests/test_global_id.py

@@ -1,6 +1,8 @@
-from ..node import Node, GlobalID
+from graphql_relay import to_global_id
 
-from ...types import NonNull, ID
+from ..node import Node, GlobalID
+from ...types import NonNull, ID, ObjectType, String
+from ...types.definitions import GrapheneObjectType
 
 
 class CustomNode(Node):
@@ -9,6 +11,26 @@ class CustomNode(Node):
         name = 'Node'
 
 
+class User(ObjectType):
+
+    class Meta:
+        interfaces = [CustomNode]
+    name = String()
+
+
+class Info(object):
+
+    def __init__(self, parent_type):
+        self.parent_type = GrapheneObjectType(
+            graphene_type=parent_type,
+            name=parent_type._meta.name,
+            description=parent_type._meta.description,
+            fields=None,
+            is_type_of=parent_type.is_type_of,
+            interfaces=None
+        )
+
+
 def test_global_id_defaults_to_required_and_node():
     gid = GlobalID()
     assert isinstance(gid.type, NonNull)
@@ -20,3 +42,19 @@ def test_global_id_allows_overriding_of_node_and_required():
     gid = GlobalID(node=CustomNode, required=False)
     assert gid.type == ID
     assert gid.node == CustomNode
+
+
+def test_global_id_defaults_to_info_parent_type():
+    my_id = '1'
+    gid = GlobalID()
+    id_resolver = gid.get_resolver(lambda *_: my_id)
+    my_global_id = id_resolver(None, None, None, Info(User))
+    assert my_global_id == to_global_id(User._meta.name, my_id)
+
+
+def test_global_id_allows_setting_customer_parent_type():
+    my_id = '1'
+    gid = GlobalID(parent_type=User)
+    id_resolver = gid.get_resolver(lambda *_: my_id)
+    my_global_id = id_resolver(None, None, None, None)
+    assert my_global_id == to_global_id(User._meta.name, my_id)