def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def visitdir(self, dir):
        matched = self._matcher.match_recursive(dir)
        if matched is None:
            return True
        elif matched is True:
            return "all"
        else:
            assert matched is False
            return False