Adding a unit test for nfv_client shell

The nfv_client component had no unit tests, so coverage report
was not including it.

By adding this simple unit test, nfv_client is included
in the nfv coverage report.

This set of unit tests does some simple CLI shell validation

Story: 2004241
Task: 27765
Change-Id: Ic7054974e1c04abcbc2c6416ec33c6ee99928348
Signed-off-by: Al Bailey <Al.Bailey@windriver.com>

nfv/nfv-tests/nfv_unit_tests/tests/test_nfv_client.py

@@ -0,0 +1,110 @@
+#
+# Copyright
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+import mock
+import os
+from . import testcase
+from nfv_client import shell
+
+
+class TestNFVClientShell(testcase.NFVTestCase):
+
+    def setUp(self):
+        super(TestNFVClientShell, self).setUp()
+
+    def tearDown(self):
+        super(TestNFVClientShell, self).tearDown()
+
+    # -- Failure cases --
+    # Each failure case will :
+    # - invoke _print_message (as part of exit)
+    # - invoke print_usage (to indicate proper arguments)
+    # - raise a SystemExit exception
+    @mock.patch('argparse.ArgumentParser._print_message')
+    @mock.patch('argparse.ArgumentParser.print_usage')
+    def _test_shell_bad_or_empty_args(self,
+                                      mock_usage=None,
+                                      mock_message=None,
+                                      shell_args=None):
+        self.assertRaises(SystemExit, shell.process_main, shell_args)
+        mock_usage.assert_called_once()
+        mock_message.assert_called_once()
+
+    # invalid arguments causes process_main to exit
+    def test_shell_bad_args(self):
+        shell_args = ['invalid-arg', ]
+        self._test_shell_bad_or_empty_args(shell_args=shell_args)
+
+    # empty arguments causes process_main to exit
+    def test_shell_no_args(self):
+        shell_args = []
+        self._test_shell_bad_or_empty_args(shell_args=shell_args)
+
+    # upgrade-strategy expects additional arguments
+    def test_shell_upgrade_strategy_incomplete_args(self):
+        shell_args = ['upgrade-strategy', ]
+        self._test_shell_bad_or_empty_args(shell_args=shell_args)
+
+    # patch-strategy expects additional arguments
+    def test_shell_patch_strategy_incomplete_args(self):
+        shell_args = ['patch-strategy', ]
+        self._test_shell_bad_or_empty_args(shell_args=shell_args)
+
+    # --- Help Cases ----
+    # -h will print_help and SystemExit
+    @mock.patch('argparse.ArgumentParser.print_help')
+    def _test_shell_help(self, mock_help=None, shell_args=None):
+        self.assertRaises(SystemExit, shell.process_main, shell_args)
+        mock_help.assert_called_once()
+
+    def test_shell_upgrade_strategy_help(self):
+        shell_args = ['upgrade-strategy', '-h', ]
+        self._test_shell_help(shell_args=shell_args)
+
+    def test_shell_patch_strategy_help(self):
+        shell_args = ['patch-strategy', '-h', ]
+        self._test_shell_help(shell_args=shell_args)
+
+    # -- Show commands --
+    # Both patch-strategy and upgrade-strategy use the same underlying
+    # sw_update class, but with different modes
+
+    # Test the show commands are not invoked when env values missing
+    @mock.patch('nfv_client.sw_update.show_strategy')
+    def _test_shell_show_missing_env(self, mock_show=None, shell_args=None):
+        shell.process_main(shell_args)
+        mock_show.assert_not_called()
+
+    def test_shell_upgrade_strategy_show_missing_env(self):
+        shell_args = ['upgrade-strategy', 'show', ]
+        self._test_shell_show_missing_env(shell_args=shell_args)
+
+    def test_shell_patch_strategy_show_missing_env(self):
+        shell_args = ['patch-strategy', 'show', ]
+        self._test_shell_show_missing_env(shell_args=shell_args)
+
+    # Test the show commands are invoked when env values detected
+    @mock.patch.dict(os.environ,
+                     {'OS_AUTH_URL': 'FAKE_OS_AUTH_URL',
+                      'OS_PROJECT_NAME': 'FAKE_OS_PROJECT_NAME',
+                      'OS_PROJECT_DOMAIN_NAME': 'FAKE_OS_PROJECT_DOMAIN_NAME',
+                      'OS_USERNAME': 'FAKE_OS_USERNAME',
+                      'OS_PASSWORD': 'FAKE_OS_PASSWORD',
+                      'OS_USER_DOMAIN_NAME': 'FAKE_OS_USER_DOMAIN_NAME',
+                      'OS_REGION_NAME': 'FAKE_OS_REGION_NAME',
+                      'OS_INTERFACE': 'FAKE_OS_INTERFACE'
+                     })
+    @mock.patch('nfv_client.sw_update.show_strategy')
+    def _test_shell_show(self, mock_show=None, shell_args=None):
+        shell.process_main(shell_args)
+        mock_show.assert_called_once()
+
+    def test_shell_upgrade_strategy_show(self):
+        shell_args = ['upgrade-strategy', 'show', ]
+        self._test_shell_show(shell_args=shell_args)
+
+    def test_shell_patch_strategy_show(self):
+        shell_args = ['patch-strategy', 'show', ]
+        self._test_shell_show(shell_args=shell_args)