Add test for no arguments

Add a test that no arguments to the pbrx command works.

Change-Id: If429ae03feb1a8c6bb662444c31cbbcf7ac1eece

pbrx/tests/test_command.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+
+# 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 fixtures
+
+from pbrx.cmd import main
+from pbrx.tests import base
+
+
+class TestCommand(base.TestCase):
+
+    def patch_argv(self, *args):
+        argv = ["pbrx"]
+        argv.extend(args)
+        self.useFixture(fixtures.MonkeyPatch("sys.argv", argv))
+
+    def test_no_args(self):
+        '''Test no arguments to the command'''
+        self.patch_argv()
+        main.main()