Added config opts unit tests

Increasing the test coverage on the opts code.

Change-Id: I334f7b6983b98581d9f1236f6ee9f0791b585695

designate/tests/unit/test_conf.py

@@ -0,0 +1,53 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+import mock
+import oslotest.base
+
+from designate.conf import opts
+from designate.conf import worker
+
+
+class TestConfOpts(oslotest.base.BaseTestCase):
+    def setUp(self):
+        super(TestConfOpts, self).setUp()
+
+    def test_opts_tupleize(self):
+        self.assertEqual([('a', 'b')], opts._tupleize({'a': 'b'}))
+
+    def test_opts_list(self):
+        self.assertIsInstance(opts.list_opts(), list)
+
+    @mock.patch('pkgutil.iter_modules')
+    def test_opts_list_module_names(self, mock_iter_modules):
+        mock_iter_modules.return_value = iter(
+            [
+                (None, 'api', False),
+                (None, 'worker', False),
+                (None, 'unknown', True),
+            ]
+        )
+
+        self.assertEqual(['api', 'worker'], opts._list_module_names())
+
+    def test_opts_import_modules(self):
+        self.assertEqual([worker], opts._import_modules(['worker']))
+
+    @mock.patch('importlib.import_module')
+    def test_opts_import_invalid_module(self, mock_import_module):
+        mock_import_module.return_value = None
+
+        self.assertRaisesRegex(
+            Exception,
+            "The module 'designate.conf.invalid' should have a 'list_opts' "
+            "function which returns the config options.",
+            opts._import_modules, ['invalid']
+        )