os.scandir(): add option to yield the given path itself

Feature or enhancement

I think it would be nice if os.scandir() had an option (that defaults to the current behaviour) which makes it also yield the root path itself as given by its path argument.

The benefit would be, that if one has code like e.g.:

def scandirtree(path):
    for p in os.scandir(path):
        if p.is_dir(follow_symlinks=False):
            yield p
            yield from scandirtree(p)
        else:
            yield p

one would also yield path and process that as well (in whatever one does with the generator).

It doesn't seem to be possible right now to write a warpper around scandir which would just yield path first, since one cannot create os.DirEntry objects (see #71983).

Pitch

The above in turn would be the familiar behaviour of many tools, e.g.

$ rm -rf path

also removes the path itself, not just its contents.

find path

also finds path itself.
Etc. pp.

So anyone who wants to implement a tool like these or similar behaviour, would no longer need to specially handle the path itself.

Previous discussion

https://discuss.python.org/t/os-scandir-should-have-an-option-to-also-yield-the-path-itself/18383

Thanks,
Chris.

从 os.scandir() 入口点开始，审查 issue #71983 及其链接讨论中讨论的相关限制。定义一种 opt-in 行为，在保留当前默认行为的同时，将给定路径本身作为兼容结果返回，然后添加 coverage 以展示这两种行为。