morepathlib.py

from pathlib import Path
_Path = type(Path())

class Path(_Path):
    def __iter__(self):
        if self.is_dir():
            return self.iterdir()

        raise TypeError

    def with_stem(self, new_stem):
        """
        >>> p = Path('spam/ham/egg.py')
        >>> p.with_stem('hoge') == Path('spam/ham/hoge.py')
        True
        """
        return self.with_name(
            new_stem + self.suffix
        )

    def rename(self, arg):
        if isinstance(arg, str):
            _Path.rename(self, arg)
            return

        if callable(arg):
            new_name = arg(self.stem)
            _Path.rename(
                self, self.with_stem(new_name)
            )
            return

        raise TypeError
        
if __name__ == '__main__':
    import doctest
    doctest.testmod()