def test_cli_parser_has_description():

    parser = gimmecert.cli.get_parser()

    assert parser.description

def test_parser_sets_up_default_callback_function():

    parser = gimmecert.cli.get_parser()

    assert callable(parser.get_default('func'))

@mock.patch('gimmecert.cli.argparse.ArgumentParser.print_usage')

def test_parser_default_callback_function_calls_print_usage(mock_print_usage):

    parser = gimmecert.cli.get_parser()

    func = parser.get_default('func')

    func(mock.Mock())

    assert mock_print_usage.called

@mock.patch('gimmecert.cli.get_parser')

def test_main_invokes_parser_function(mock_get_parser):

    mock_parser = mock.Mock()

    mock_args = mock.Mock()

    mock_parser.parse_args.return_value = mock_args

    mock_get_parser.return_value = mock_parser

    gimmecert.cli.main()

    mock_args.func.assert_called_once_with(mock_args)