fix call obj_reset_changes with recursive=True raise error

when call  obj_reset_changes with recursive=True, the function raise:
ERROR oslo_messaging.rpc.server AttributeError: 'list' object has no attribute
'ObjectField'

Change-Id: I9559a80190eb44475452aac4e3553f921311723b

2 files changed, 19 insertions, 2 deletions

diff --git a/designate/objects/base.py b/designate/objects/base.py
index de7fa822..2ed893c5 100644
--- a/designate/objects/base.py
+++ b/designate/objects/base.py
@@ -18,6 +18,8 @@ from oslo_versionedobjects import exception
 from oslo_utils import excutils
 from designate.i18n import _
 from oslo_versionedobjects import base
+from oslo_versionedobjects import fields as ovoo_fields
+
 from oslo_versionedobjects.base import VersionedObjectDictCompat as DictObjectMixin  # noqa
 
 from designate.objects import fields
@@ -226,10 +228,10 @@ class DesignateObject(base.VersionedObject):
                     continue
 
                 # Reset straight Object and ListOfObjects fields
-                if isinstance(self.fields[field], self.obj_fields.ObjectField):
+                if isinstance(self.fields[field], ovoo_fields.ObjectField):
                     value.obj_reset_changes(recursive=True)
                 elif isinstance(self.fields[field],
-                                self.obj_fields.ListOfObjectsField):
+                                ovoo_fields.ListOfObjectsField):
                     for thing in value:
                         thing.obj_reset_changes(recursive=True)
 
diff --git a/designate/tests/unit/objects/test_base.py b/designate/tests/unit/objects/test_base.py
index 15b913d9..3b3fa23e 100644
--- a/designate/tests/unit/objects/test_base.py
+++ b/designate/tests/unit/objects/test_base.py
@@ -405,6 +405,21 @@ class DesignateObjectTest(oslotest.base.BaseTestCase):
         self.assertEqual(1, len(obj.obj_what_changed()))
         self.assertEqual({'name': "My Name"}, obj.obj_get_changes())
 
+    def test_obj_reset_changes_recursive(self):
+        obj = TestObject()
+        obj.id = "My ID"
+        obj.name = "My Name"
+        obj.nested = TestObject()
+        obj.nested.id = "My ID"
+
+        self.assertEqual(3, len(obj.obj_what_changed()))
+
+        obj.obj_reset_changes()
+        self.assertEqual(1, len(obj.obj_what_changed()))
+
+        obj.obj_reset_changes(recursive=True)
+        self.assertEqual(0, len(obj.obj_what_changed()))
+
     def test_obj_get_original_value(self):
         # Create an object
         obj = TestObject()