pre-commit/pre_commit/error_handler.py

from __future__ import absolute_import
from __future__ import print_function
from __future__ import unicode_literals

import contextlib
import os.path
import sys
import traceback

import six

import pre_commit.constants as C
from pre_commit import five
from pre_commit import output
from pre_commit.store import Store


class FatalError(RuntimeError):
    pass


def _to_bytes(exc):
    try:
        return bytes(exc)
    except Exception:
        return six.text_type(exc).encode('UTF-8')


def _log_and_exit(msg, exc, formatted):
    error_msg = b''.join((
        five.to_bytes(msg), b': ',
        five.to_bytes(type(exc).__name__), b': ',
        _to_bytes(exc), b'\n',
    ))
    output.write(error_msg)
    store = Store()
    log_path = os.path.join(store.directory, 'pre-commit.log')
    output.write_line('Check the log at {}'.format(log_path))

    with open(log_path, 'wb') as log:
        output.write_line(
            '### version information\n```', stream=log,
        )
        output.write_line(
            'pre-commit.version: {}'.format(C.VERSION), stream=log,
        )
        output.write_line(
            'sys.version:\n{}'.format(
                '\n'.join(
                    [
                        '    {}'.format(line)
                        for line in sys.version.splitlines()
                    ],
                ),
            ),
            stream=log,
        )
        output.write_line(
            'sys.executable: {}'.format(sys.executable), stream=log,
        )
        output.write_line('os.name: {}'.format(os.name), stream=log)
        output.write_line(
            'sys.platform: {}\n```'.format(sys.platform), stream=log,
        )
        output.write_line('### error information\n```', stream=log)
        output.write(error_msg, stream=log)
        output.write_line(formatted, stream=log)
        output.write('\n```\n', stream=log)
    raise SystemExit(1)


@contextlib.contextmanager
def error_handler():
    try:
        yield
    except (Exception, KeyboardInterrupt) as e:
        if isinstance(e, FatalError):
            msg = 'An error has occurred'
        elif isinstance(e, KeyboardInterrupt):
            msg = 'Interrupted (^C)'
        else:
            msg = 'An unexpected error has occurred'
        _log_and_exit(msg, e, traceback.format_exc())