Improve UT coverage

tests/test_rfc4363.py

@@ -0,0 +1,28 @@
+import os
+import sys
+from unittest import TestCase
+
+if sys.version_info.major == 3:
+    from unittest import mock
+else:
+    import mock
+
+modules_path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+sys.path.insert(0, os.path.join(modules_path, 'src'))
+
+from sonic_ax_impl.mibs.ietf.rfc4363 import FdbUpdater
+
+class TestFdbUpdater(TestCase):
+
+    @mock.patch('sonic_ax_impl.mibs.Namespace.dbs_keys', mock.MagicMock(return_value=(['ASIC_STATE:SAI_OBJECT_TYPE_FDB_ENTRY:{"bvid":"oid:0x26000000000b6c","mac":"60:45:BD:98:6F:48","switch_id":"oid:0x21000000000000"}'])))
+    @mock.patch('sonic_ax_impl.mibs.Namespace.dbs_get_all', mock.MagicMock(return_value=({"nexthop": "10.0.0.1,10.0.0.3", "ifname": "Ethernet0,Ethernet4"})))
+    def test_FdbUpdater_ent_bridge_port_id_attr_missing(self):
+        updater = FdbUpdater()
+
+        with mock.patch('sonic_ax_impl.mibs.logger.error') as mocked_error:
+            updater.update_data()
+
+            # check warning
+            mocked_error.assert_called()
+
+        self.assertTrue(len(updater.vlanmac_ifindex_list) == 0)