比起使用递归，使用队列和while循环可能更容易，这样你就不必传递大量的容器，也不必担心调用堆栈的大小。

def get_subpaths(path_name):
    results = []
    search_queue = {path_name}

    while search_queue:
        search_path = search_queue.pop()
        results.append(search_path)
        print(f"{search_path=}")

        for path in get_path_from_api(path=search_path):
            if path.is_directory:
                search_queue.add(path.name)

    return results

from queue import deque

simulated_filesystem = {
        '': ['path1', 'path2', 'path3'],
        'path1': ['path1/subpath1', 'path1/subpath2'],
        'path2': ['path2/subpath1', 'path2/subpath2'],
        'path3': ['path3/subpath3'],
}

class ApiPathObject:
    def __init__(self, name):
        self.is_directory = True
        self.name = name
    def __repr__(self):
        return f"{self.name}"

def get_path_from_api(path) -> list[ApiPathObject]:
    return [ApiPathObject(name) for name in simulated_filesystem.get(path, [])]

def get_subpaths_bfs(path_name):
    """ generator, breadth first search, using a python list as a stack """
    paths = [path_name]
    while paths:
        for path in get_path_from_api(paths.pop()):
            if path.is_directory:
                paths.append(path.name)
                yield path.name

def get_subpaths_dfs(path_name):
    """ generator, depth first search, preorder """
    paths = deque(get_path_from_api(path_name))
    while paths:
        path = paths.popleft()
        if path.is_directory:
            yield path.name
            for subpath in reversed(get_path_from_api(path.name)):
                paths.appendleft(subpath)

def get_subpaths(path_name):
    return list(get_subpaths_dfs(path_name))

print(get_subpaths(''))
print(get_subpaths('path1'))
print(get_subpaths('path2'))

['path1'，'path1/subpath1'，'path1/subpath2'，' path2'，'path2/subpath1'，'path2/subpath2'，'path3'，'path3/subpath3']
[“路径1/子路径1”，“路径1/子路径2”]
[“路径2/子路径1”，“路径2/子路径2”]