new_contents: #!/usr/bin/env python3
  
  import argparse
  import os
  import shutil
  import subprocess
  import sys
  import tarfile
  import tempfile
  import urllib.request
  
  BASE_URL = "https://github.com/nodejs/gyp-next/archive/"
  CHECKOUT_PATH = os.path.dirname(os.path.realpath(__file__))
  CHECKOUT_GYP_PATH = os.path.join(CHECKOUT_PATH, 'gyp')
  
  parser = argparse.ArgumentParser()
  parser.add_argument("tag", help="gyp tag to update to")
  args = parser.parse_args()
  
  tar_url = BASE_URL + args.tag + ".tar.gz"
  
  changed_files = subprocess.check_output(["git", "diff", "--name-only"]).strip()
  if changed_files:
    raise Exception("Can't update gyp while you have uncommitted changes in node-gyp")
  
  with tempfile.TemporaryDirectory() as tmp_dir:
    tar_file = os.path.join(tmp_dir, 'gyp.tar.gz')
    unzip_target = os.path.join(tmp_dir, 'gyp')
    with open(tar_file, 'wb') as f:
      print("Downloading gyp-next@" + args.tag + " into temporary directory...")
      print("From: " + tar_url)
      with urllib.request.urlopen(tar_url) as in_file:
          f.write(in_file.read())
  
      print("Unzipping...")
      with tarfile.open(tar_file, "r:gz") as tar_ref:
        tar_ref.extractall(unzip_target)
      
      print("Moving to current checkout (" + CHECKOUT_PATH + ")...")
      if os.path.exists(CHECKOUT_GYP_PATH):
        shutil.rmtree(CHECKOUT_GYP_PATH)
      shutil.move(os.path.join(unzip_target, os.listdir(unzip_target)[0]), CHECKOUT_GYP_PATH)
  
  subprocess.check_output(["git", "add", "gyp"], cwd=CHECKOUT_PATH)
  subprocess.check_output(["git", "commit", "-m", "gyp: update gyp to " + args.tag])
  
subject: add update-gyp script