contrib/vulture

#!/usr/bin/env vpython3
# Copyright 2021 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# [VPYTHON:BEGIN]
# python_version: "3.11"
#
# wheel: <
#   name: "infra/python/wheels/vulture-py3"
#   version: "version:2.3"
# >
# wheel: <
#   name: "infra/python/wheels/toml-py3"
#   version: "version:0.10.1"
# >
# [VPYTHON:END]

"""Run vulture over the codebase to find dead code.

Note: This needs to be fed all modules to determine whether anything is used.
"""

import os
from pathlib import Path
import subprocess
import sys

import vulture.core  # pylint: disable=import-error


TOPDIR = Path(__file__).resolve().parent.parent


def main(argv):
    """Main function."""
    if not argv:
        os.chdir(TOPDIR)

        # Scan all python modules (except generated bindings) that we authored.
        result = subprocess.run(
            ["git", "ls-tree", "-r", "-z", "HEAD"],
            check=True,
            encoding="utf-8",
            stdout=subprocess.PIPE,
        )
        for entry in result.stdout.split("\0"):
            if not entry:
                continue
            fields, path = entry.split("\t", 1)
            mode, _ = fields.split(" ", 1)
            if (
                mode != "120000"
                and not path.startswith("third_party/")
                and path.endswith(".py")
                and not path.endswith("_pb2.py")
            ):
                argv.append(path)

    argv = [
        "--ignore-names",
        "test*,setUp,setUpClass,tearDown,tearDownClass",
    ] + argv

    # The vulture API doesn't accept explicit args.
    sys.argv = [sys.argv[0]] + argv
    vulture.core.main()


if __name__ == "__main__":
    sys.exit(main(sys.argv[1:]))