用 Python 批量重命名文件：默认预览、冲突检查与显式执行

"""Preview or apply space-to-underscore renames. Python 3.10+, Linux."""
import argparse
import json
from pathlib import Path
import stat
import sys


def occupied(path):
    try:
        path.lstat()  # A dangling symlink also occupies a name.
    except FileNotFoundError:
        return False
    return True


def make_plan(directory):
    if not directory.is_dir():
        raise ValueError(f"not a directory: {directory}")
    plan = []
    targets = set()
    for source in sorted(directory.iterdir()):
        if not stat.S_ISREG(source.lstat().st_mode):
            continue
        name = source.name.replace(" ", "_")
        if name == source.name:
            continue
        target = source.with_name(name)
        if target in targets or occupied(target):
            raise ValueError(f"target collision: {target.name!r}")
        targets.add(target)
        plan.append((source, target))
    return plan


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("directory", type=Path)
    parser.add_argument("--apply", action="store_true", help="perform the renames")
    args = parser.parse_args()
    completed = 0
    try:
        plan = make_plan(args.directory.resolve(strict=True))
        for source, target in plan:
            print(json.dumps({"from": source.name, "to": target.name}), flush=True)
        print(f"PLAN: {len(plan)} file(s)", flush=True)
        if not args.apply:
            print("DRY RUN: no files renamed")
            return 0
        for source, target in plan:
            if not stat.S_ISREG(source.lstat().st_mode) or occupied(target):
                raise ValueError("directory changed; stop and inspect")
            source.rename(target)
            completed += 1
            print(f"RENAMED: {json.dumps(target.name)}", flush=True)
    except (OSError, ValueError) as exc:
        print(f"ERROR after {completed} rename(s): {exc}", file=sys.stderr)
        return 1
    print(f"DONE: {completed} file(s)")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())

python3 --version
python3 rename_spaces.py --help
mkdir rename-demo
printf 'alpha\n' > 'rename-demo/report one.txt'
printf 'beta\n' > 'rename-demo/report two.txt'
python3 rename_spaces.py rename-demo

{"from": "report one.txt", "to": "report_one.txt"}
{"from": "report two.txt", "to": "report_two.txt"}
PLAN: 2 file(s)
DRY RUN: no files renamed

python3 rename_spaces.py rename-demo --apply
python3 - <<'PYCODE'
from pathlib import Path
root = Path("rename-demo")
assert sorted(p.name for p in root.iterdir()) == ["report_one.txt", "report_two.txt"]
assert (root / "report_one.txt").read_text() == "alpha\n"
assert (root / "report_two.txt").read_text() == "beta\n"
print("OK: names changed; contents preserved")
PYCODE
python3 rename_spaces.py rename-demo --apply

PLAN: 0 file(s)
DONE: 0 file(s)

mkdir rename-conflict
printf 'original\n' > 'rename-conflict/a b.txt'
printf 'keep\n' > 'rename-conflict/a_b.txt'
python3 rename_spaces.py rename-conflict --apply
printf 'exit=%s\n' "$?"
cat 'rename-conflict/a b.txt' 'rename-conflict/a_b.txt'

ERROR after 0 rename(s): target collision: 'a_b.txt'
exit=1
original
keep