def METHOD_NAME(self, cmdline_test):
    """Test parsing of commands.
    See https://github.com/qutebrowser/qutebrowser/issues/615
    Args:
        cmdline_test: A pytest fixture which provides testcases.
    """
    p = parser.CommandParser()
    if cmdline_test.valid:
        p.parse_all(cmdline_test.cmd, aliases=False)
    else:
        with pytest.raises(cmdexc.NoSuchCommandError):
            p.parse_all(cmdline_test.cmd, aliases=False)