pylint_main.py

#!/usr/bin/env python3
# Copyright 2019 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Chromium wrapper for pylint for passing args via stdin.

This will be executed by vpython with the right pylint versions.
"""

from __future__ import print_function

import os
import sys

HERE = os.path.dirname(os.path.abspath(__file__))
PYLINT = os.path.join(HERE, 'pylint_main.py')
RC_FILE = os.path.join(HERE, 'pylintrc')

ARGS_ON_STDIN = '--args-on-stdin'


def main(argv):
    """Our main wrapper."""
    # Add support for a custom mode where arguments are fed line by line on
    # stdin. This allows us to get around command line length limitations.
    if ARGS_ON_STDIN in argv:
        argv = [x for x in argv if x != ARGS_ON_STDIN]
        argv.extend(x.strip() for x in sys.stdin)

    # Set default config options with the PYLINTRC environment variable. This
    # will allow overriding with "more local" config file options, such as a
    # local "pylintrc" file, the "--rcfile" command-line flag, or an existing
    # PYLINTRC.
    #
    # Note that this is not quite the same thing as replacing pylint's built-in
    # defaults, since, based on config file precedence, it will not be
    # overridden by "more global" config file options, such as ~/.pylintrc,
    # ~/.config/pylintrc, or /etc/pylintrc. This is generally the desired
    # behavior, since we want to enforce these defaults in most cases, but allow
    # them to be overridden for specific code or repos.
    #
    # If someone really doesn't ever want the depot_tools pylintrc, they can set
    # their own PYLINTRC, or set an empty PYLINTRC to use pylint's normal config
    # file resolution, which would include the "more global" options that are
    # normally overridden by the depot_tools config.
    if os.path.isfile(RC_FILE) and 'PYLINTRC' not in os.environ:
        os.environ['PYLINTRC'] = RC_FILE

    # This import has to happen after PYLINTRC is set because the module tries
    # to resolve the config file location on load.
    from pylint import lint  # pylint: disable=bad-option-value,import-outside-toplevel
    lint.Run(argv)


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