@classmethod
def detect(cls, old_config, new_config):
    """Detect if command line call in `new_config` differs from `old_config`"""
    old_nameless_args = cls.get_nameless_args(old_config)
    new_nameless_args = cls.get_nameless_args(new_config)
    if old_nameless_args != new_nameless_args:
        yield cls(old_config, new_config)
