Python：使用异步/等待的递归

Question

这是一些用于遍历文件树的简单工作代码。它采用了同步发电机的概念：

def list_dir_groom(abs_path):
    """Returns the list of directories
    and the list of files ([abs_path] offspring).
    """
    dirs, files = [], []

    for i in os.listdir(abs_path):
        if i[0] != ".":
            x = abs_path.joinpath(i)
            if x.is_dir():
                dirs.append(x)
            else:
                if is_target_file(x):
                    files.append(x)

    return dirs, files


def traverse_target_tree(tgt_dir):
    """Recursively traverses the target directory [tgt_dir]
    and yields a sequence of file names.
    """
    dirs, files = list_dir_groom(tgt_dir)

    for d in dirs:
        yield from traverse_target_tree(d)

    for f in files:
        yield f


def tweak():
    """Tweak all files.
    """
    for i in traverse_target_tree(ARGS.tgt_dir):
        print(f"{i}")

出于教育目的，我一直在尝试使用asyncio（python3.8.1）重写它。当然，这不是正常工作：

async def traverse_target_tree_async(tgt_dir):
    """Recursively traverses the target directory [tgt_dir]
    and yields a sequence of file names.
    """
    dirs, files = list_dir_groom(tgt_dir)

    for d in dirs:
        yield traverse_target_tree_async(d)

    for f in files:
        yield f


async def tweak_async():
    """Tweak all files.
    """
    async for i in traverse_target_tree_async(ARGS.tgt_dir):
        print(f"{i}")

...

asyncio.run(tweak_async())

示例输出如下所示：

<async_generator object traverse_target_tree_async at 0x7f4993429ca0>
<async_generator object traverse_target_tree_async at 0x7f4993429d30>
<async_generator object traverse_target_tree_async at 0x7f4993429ca0>
<async_generator object traverse_target_tree_async at 0x7f4993429d30>
/home/user/spaces/python/tex-tweak/n.vim
/home/user/spaces/python/tex-tweak/README.md
/home/user/spaces/python/tex-tweak/pyproject.toml
/home/user/spaces/python/tex-tweak/poetry.lock

在某种程度上，这是有道理的，但我不知道我应该做的最后一步是什么

Answer 1

建议解决方案here。多亏了Sraw

async def traverse_target_tree_async(tgt_dir):
    """Recursively traverses the target directory [tgt_dir]
    and yields a sequence of file names.
    """
    dirs, files = list_dir_groom(tgt_dir)

    for d in dirs:
        async for f in traverse_target_tree_async(d):
            yield f

    for f in files:
        yield f