foobar.py

foobar.py

#!/usr/bin/env python3

# preconditions
# touch foo.txt
# echo "foo" > foo.txt
# python foobar.py /path/to/foo.txt # no changes
# echo "bar" > foo.txt
# python foobar.py /path/to/foo.txt # will rename foo.txt to bar.txt

import sys
import os
from pathlib import Path

filepath = sys.argv[1]
# ex. /home/souto/foo.txt

filestem = Path(filepath).stem
parentdir = Path(filepath).parent

if not os.path.isfile(filepath):
    print("file not found, nothing else to do")
    sys.exit()

with open(filepath) as f:
    content = f.read().strip()

if content != filestem:
    print(f"Rename {filepath} to {parentdir}/{content}.txt")
    os.rename(filepath, f"{parentdir}/{content}.txt")