def main()

in script/patches-mtime-cache.py [0:0]

• 90 lines of code
• 12 McCabe index (conditional complexity)

def main():
    parser = argparse.ArgumentParser(
        description="Make mtime cache for patched files"
    )
    subparsers = parser.add_subparsers(
        dest="operation", help="sub-command help"
    )

    apply_subparser = subparsers.add_parser(
        "apply", help="apply the mtimes from the cache"
    )
    apply_subparser.add_argument(
        "--cache-file", required=True, help="mtime cache file"
    )
    apply_subparser.add_argument(
        "--preserve-cache",
        action="store_true",
        help="don't delete cache after applying",
    )

    generate_subparser = subparsers.add_parser(
        "generate", help="generate the mtime cache"
    )
    generate_subparser.add_argument(
        "--cache-file", required=True, help="mtime cache file"
    )

    set_subparser = subparsers.add_parser(
        "set", help="set all mtimes to a specific date"
    )
    set_subparser.add_argument(
        "--mtime",
        type=int,
        required=True,
        help="mtime to use for all patched files",
    )

    for subparser in [generate_subparser, set_subparser]:
        subparser.add_argument(
            "--patches-config",
            type=argparse.FileType("r"),
            required=True,
            help="patches' config in the JSON format",
        )

    args = parser.parse_args()

    if args.operation == "generate":
        try:
            # Cache file may exist from a previously aborted sync. Reuse it.
            with open(args.cache_file, mode="r") as f:
                json.load(f)  # Make sure it's not an empty file
                print("Using existing mtime cache for patches")
                return 0
        except Exception:
            pass

        try:
            with open(args.cache_file, mode="w") as f:
                mtime_cache = generate_cache(json.load(args.patches_config))
                json.dump(mtime_cache, f, indent=2)
        except Exception:
            print(
                "ERROR: failed to generate mtime cache for patches",
                file=sys.stderr,
            )
            traceback.print_exc(file=sys.stderr)
            return 0
    elif args.operation == "apply":
        if not os.path.exists(args.cache_file):
            print("ERROR: --cache-file does not exist", file=sys.stderr)
            return 0  # Cache file may not exist, fail more gracefully

        try:
            with open(args.cache_file, mode="r") as f:
                apply_mtimes(json.load(f))

            if not args.preserve_cache:
                os.remove(args.cache_file)
        except Exception:
            print(
                "ERROR: failed to apply mtime cache for patches",
                file=sys.stderr,
            )
            traceback.print_exc(file=sys.stderr)
            return 0
    elif args.operation == "set":
        # Python 2/3 compatibility
        try:
            user_input = raw_input
        except NameError:
            user_input = input

        answer = user_input(
            "WARNING: Manually setting mtimes could mess up your build. "
            "If you're sure, type yes: "
        )

        if answer.lower() != "yes":
            print("Aborting")
            return 0

        set_mtimes(json.load(args.patches_config), args.mtime)

    return 0