Add unit test for old environment

build-nodes-json still needs to be able to handle old environments
that used parameters for most of the options.  This is a follow-up
to the previous commit that fixed the problem.

openstack_virtual_baremetal/tests/test_build_nodes_json.py

@@ -90,6 +90,27 @@ class TestBuildNodesJson(testtools.TestCase):
         self.assertEqual('provision-foo', provision_net)
         self.assertEqual('undercloud', undercloud_name)
 
+    @mock.patch('openstack_virtual_baremetal.build_nodes_json.open',
+                create=True)
+    @mock.patch('yaml.safe_load')
+    def test_get_names_old_env(self, mock_load, mock_open):
+        args = mock.Mock()
+        args.env = 'foo.yaml'
+        args.add_undercloud = False
+        mock_env = {'parameters':
+                        {'bmc_prefix': 'bmc-foo',
+                         'baremetal_prefix': 'baremetal-foo',
+                         'provision_net': 'provision-foo'
+                         },
+                    }
+        mock_load.return_value = mock_env
+        bmc_base, baremetal_base, provision_net, undercloud_name = (
+            build_nodes_json._get_names(args))
+        self.assertEqual('bmc-foo', bmc_base)
+        self.assertEqual('baremetal-foo', baremetal_base)
+        self.assertEqual('provision-foo', provision_net)
+        self.assertIsNone(undercloud_name)
+
     @mock.patch('openstack_virtual_baremetal.build_nodes_json.open',
                 create=True)
     @mock.patch('yaml.safe_load')