view hgdemandimport/tracing.py @ 42129:232a33a11ce0

pull: deal with locally filtered changeset passed into --rev

Nowadays, it is possible to explicitly pull a remote revision that end up being
hidden locally (eg: obsoleted locally). However before this patch, some
internal processing where crashing trying to resolve a filtered revision.

Without this patches, the pull output result a confusing output:

  $ hg pull ../repo-Bob --rev 956063ac4557
  pulling from ../repo-Bob
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 0 changes to 2 files (+1 heads)
  (2 other changesets obsolete on arrival)
  abort: 00changelog.i@956063ac4557828781733b2d5677a351ce856f59: filtered node!

# 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 absolute_import

import contextlib
import os

_pipe = None
_checked = False

@contextlib.contextmanager
def log(whencefmt, *whenceargs):
    global _pipe, _session, _checked
    if _pipe is None:
        if _checked:
            yield
            return
        _checked = True
        if 'HGCATAPULTSERVERPIPE' not in os.environ:
            yield
            return
        _pipe = open(os.environ['HGCATAPULTSERVERPIPE'], 'w', 1)
        _session = os.environ.get('HGCATAPULTSESSION', 'none')
    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