Fix loss of folder "date modified" on mac (e.g. from iCloud): cd ~/Documents; set_folder_date_modified.py ./

set_folder_date_modified.py

#!/usr/bin/env python

import os
import sys
import time
from datetime import datetime


def set_folder_dates(root):
    for x in os.walk(root, topdown=False):
        set_folder_date(*x)


def remove_ds_store(files):
    return [f for f in files if f != '.DS_Store']


def set_folder_date(folder, subfolders, files):
    # don't look at .DS_Store
    files = remove_ds_store(files)
    # empty folders date is lost
    # only consider subfolders with a file somewhere in their tree
    subfolders_with_files = []
    for subfolder in subfolders:
        for _, _, subfiles in os.walk(os.path.join(folder, subfolder)):
            subfiles = remove_ds_store(subfiles)
            if len(subfiles) > 0:
                break
        else:
            # if no files found then don't add
            continue
        subfolders_with_files.append(subfolder)

    date_source = [path for f in subfolders_with_files + files
                        if os.path.exists(path := os.path.join(folder, f))]
    if len(date_source) == 0:
        return

    # filter out corrupt files with modified date in the future
    mtimes = [mtime for f in date_source 
                    if (mtime := os.path.getmtime(f)) < time.time()]
    if len(mtimes) == 0:
        return
    
    newest = max(mtimes)
    stat = os.stat(folder)
    date = datetime.fromtimestamp(newest)
    print(f"Setting {folder} date to {date.strftime('%d/%m/%Y, %H:%M:%S')}")
    os.utime(folder, (stat.st_atime, newest))


if __name__ == '__main__':
    set_folder_dates(sys.argv[1])

Thank you for this! So handy, worked perfectly on the root folder I was looking to fix, all the way down to every folder inside.

I got to this page from Stack Overflow. Thanks so much for sharing the Python solution. Works great!