gitignore/scripts/strip_trailing_whitespace.py
Srikanth Patchava afdec22fa1
fix: add script to strip trailing whitespace from templates
Trailing whitespace in .gitignore patterns can cause unexpected
behavior. This script detects and removes trailing whitespace
from template files with dry-run support.

Signed-off-by: Srikanth Patchava <spatchava@meta.com>
2026-05-16 09:30:28 -07:00

79 lines
2.3 KiB
Python

#!/usr/bin/env python3
"""
Strip trailing whitespace from .gitignore template files.
This script fixes trailing whitespace issues in gitignore templates,
which can cause unexpected behavior in pattern matching.
"""
import argparse
import os
import sys
def strip_file(filepath: str, dry_run: bool = False) -> int:
"""Strip trailing whitespace from a file. Returns number of lines fixed."""
with open(filepath, "r", encoding="utf-8", errors="replace") as f:
lines = f.readlines()
fixed_count = 0
new_lines = []
for line in lines:
stripped = line.rstrip() + "\n"
if stripped != line:
fixed_count += 1
new_lines.append(stripped)
# Ensure file ends with a single newline
if new_lines and new_lines[-1] == "\n":
pass # already ends properly
elif not new_lines:
new_lines = ["\n"]
if fixed_count > 0 and not dry_run:
with open(filepath, "w", encoding="utf-8", newline="") as f:
f.writelines(new_lines)
return fixed_count
def main():
parser = argparse.ArgumentParser(
description="Strip trailing whitespace from .gitignore templates."
)
parser.add_argument("files", nargs="*", help="Files to process.")
parser.add_argument("--repo-root", default=".", help="Repo root directory.")
parser.add_argument(
"--dry-run", action="store_true", help="Report but do not modify files."
)
args = parser.parse_args()
if args.files:
targets = args.files
else:
targets = []
for entry in os.listdir(args.repo_root):
full = os.path.join(args.repo_root, entry)
if os.path.isfile(full) and entry.endswith(".gitignore"):
targets.append(full)
total_fixed = 0
for filepath in targets:
count = strip_file(filepath, dry_run=args.dry_run)
if count > 0:
action = "would fix" if args.dry_run else "fixed"
print(f" {action} {count} line(s) in {filepath}")
total_fixed += count
if total_fixed == 0:
print("No trailing whitespace found.")
else:
action = "Would fix" if args.dry_run else "Fixed"
print(f"\n{action} {total_fixed} line(s) total.")
sys.exit(0)
if __name__ == "__main__":
main()