如何迭代生成目录树，用Python实现？

Question

我已经实现了使用递归生成目录树：

import os
import re
import hashlib

PIPE = "│"
ELBOW = "└──"
TEE = "├──"
PIPE_PREFIX = "│   "
SPACE_PREFIX = "    "

root_dir = ""
tree = []

def extract_number(file_name):
    match = re.search(r"\d+", file_name)
    return int(match.group()) if match else float("inf")

def get_md5(file_path):
    hasher = hashlib.md5()
    with open(file_path, "rb") as f:
        for chunk in iter(lambda: f.read(8192), b""):
            hasher.update(chunk)
    return hasher.hexdigest()

def tree_head():
    tree.append(f"{root_dir}{os.sep}")
    tree.append(PIPE)

def get_entries(directory):
    with os.scandir(directory) as entries:
        entries = list(entries)

        entries = [entry for entry in entries if entry.name != ".DS_Store"]

        entries = sorted(entries, key = lambda entry: (entry.is_file(), extract_number(entry.name)))

    return entries

def tree_body(directory, prefix = ""):
    entries = get_entries(directory)
    entries_count = len(entries)
    for index, entry in enumerate(entries):
        connector = ELBOW if index == entries_count - 1 else TEE
        if entry.is_dir():
            add_directory(entry, index, entries_count, prefix, connector)
        else:
            add_file(entry, prefix, connector)

def add_directory(directory, index, entries_count, prefix, connector):
    tree.append(f"{prefix}{connector} {directory.name}{os.sep}")

    if index != entries_count - 1:
        prefix += PIPE_PREFIX
    else:
        prefix += SPACE_PREFIX

    tree_body(directory, prefix)

def add_file(file, prefix, connector):
    md5_hash = get_md5(file)
    tree.append(f"{prefix}{connector} {file.name} -> {md5_hash}")

def build_tree():
    tree_head()
    tree_body(root_dir)
    return tree

def generate():
    tree = build_tree()

    for entry in tree:
        print(entry)

generate()

此代码生成一个目录树，其中包含文件和目录名称及其 MD5 哈希值。以下是该脚本可能产生的输出示例（假设指定的目录结构）：

root_dir   
│
├── folder1/
│   ├── file1.txt -> d41d8cd98f00b204e9800998ecf8427e
│   └── file2.txt -> 098f6bcd4621d373cade4e832627b4f6
└── folder2/
    ├── file3.txt -> 6dcd4ce23d88e2ee9568ba546c007c63
    └── file4.txt -> d41d8cd98f00b204e9800998ecf8427e

tree_body()

函数如何从递归实现转换为迭代实现？ 我尝试了很多方法，发现很难按照正确的顺序打印。 我不知道为这个问题设计算法的正确方法是什么样的。

Answer 1

尝试使用目录类作为字典，例如（伪代码）：

Class DirBody():
    def __init__(self, name, depth):
        self.name = name
        self.depth = depth
        self.childDir = []
        self.childFile = []
    def __str__(self):
        self.printDirs()
        self.printFiles()
    def printDirs(self):
        pass
    def printFiles(self):
        pass

你可以步行