Extending pathlib.Path

import pathlib
import os
from os.path import commonprefix, relpath
import shutil


class Path(pathlib.Path):

    def __new__(cls, *args, **kwargs):
        if cls is Path:
            cls = WindowsPath if os.name == 'nt' else PosixPath
        self = cls._from_parts(args, init=False)
        if not self._flavour.is_supported:
            raise NotImplementedError("cannot instantiate %r on your system"
                                      % (cls.__name__,))
        self._init()
        return self

    def walk(self):
        for path in self.iterdir():
            if path.is_dir():
                yield from path.walk()
            else:
                yield path

    def absolute(self):
        raise AttributeError("Use resolve, not absolute")

    def chdir(self):
        os.chdir(self)
        return Path.cwd()

    def relative_to(self, other):
        return Path(relpath(self, other))

    def common_prefix(self, other):
        return Path(commonprefix((self, other)))

    def copy(self, destination, *,
             follow_symlinks=True, preserve_metadata=True):
        copy = shutil.copy2 if preserve_metadata else shutil.copy
        if self.is_dir():
            shutil.copytree(self, destination, copy_function=copy,
                            symlinks=not follow_symlinks)
        else:
            copy(self, destination, follow_symlinks=follow_symlinks)

    def move(self, destination, *, preserve_metadata=True):
        copy = shutil.copy2 if preserve_metadata else shutil.copy
        shutil.move(self, destination, copy_function=copy)

    def rmdir(self, recursive=False, ignore_errors=False):
        if recursive:
            shutil.rmtree(self, ignore_errors=ignore_errors)
        else:
            try:
                super().rmdir()
            except Exception:
                if not ignore_errors:
                    raise


class PosixPath(Path, pathlib.PurePosixPath):
    __slots__ = ()


class WindowsPath(Path, pathlib.PureWindowsPath):
    __slots__ = ()