view hgdemandimport/tracing.py @ 51985:2924676d4728

tests: force `seq` to print with '\n' EOL

It looks like consistent EOL is the reason for 0605726179a0, but now on py3,
`print()` uses the platform EOL without regard to binary mode.  The tests mostly
use this to loop over a sequence of number in the shell, but there are a handful
that redirect output to a file.  Specifically, this fixes Windows runs of
`test-bundle2-multiple-changegroups.t`, but there may be other tests this fixes.

Some other `tests/*.py` files also set binary mode on stdout, but they also
write bytes directly to `sys.stdout.buffer`.  I'm not doing that here because
PyCharm flags these write calls for passing bytes instead of str (PyCharm is
likely wrong, but possibly confused because the code falls back to `sys.stdout`
if there is no `.buffer` attribute), and it's annoying.

# Support code for event tracing in Mercurial. Lives in demandimport
# so it can also be used in demandimport.
#
# Copyright 2018 Google LLC.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import annotations

import contextlib
import os

_pipe = None
_checked = False
_session = 'none'


def _isactive():
    global _pipe, _session, _checked
    if _pipe is None:
        if _checked:
            return False
        _checked = True
        if 'HGCATAPULTSERVERPIPE' not in os.environ:
            return False
        _pipe = open(os.environ['HGCATAPULTSERVERPIPE'], 'w', 1)
        _session = os.environ.get('HGCATAPULTSESSION', 'none')
    return True


@contextlib.contextmanager
def log(whencefmt, *whenceargs):
    if not _isactive():
        yield
        return
    whence = whencefmt % whenceargs
    try:
        # Both writes to the pipe are wrapped in try/except to ignore
        # errors, as we can see mysterious errors in here if the pager
        # is active. Presumably other conditions could trigger
        # problems too.
        try:
            _pipe.write('START %s %s\n' % (_session, whence))
        except IOError:
            pass
        yield
    finally:
        try:
            _pipe.write('END %s %s\n' % (_session, whence))
        except IOError:
            pass


def counter(label, amount, *labelargs):
    if not _isactive():
        return
    l = label % labelargs
    # See above in log() for why this is in a try/except.
    try:
        _pipe.write('COUNTER %s %d %s\n' % (_session, amount, l))
    except IOError:
        pass