mercurial/txnutil.py
author Pulkit Goyal <pulkit@yandex-team.ru>
Fri, 30 Nov 2018 17:42:55 +0300
changeset 40766 773572e5cba2
parent 31050 206532700213
child 43076 2372284d9457
permissions -rw-r--r--
narrowcommands: remove an unrequired `repo.narrowpats` call We call that few lines above and do nothing significant in between which can change the narrowpats. So let's use values returned by that call. Differential Revision: https://phab.mercurial-scm.org/D5348

# txnutil.py - transaction related utilities
#
#  Copyright FUJIWARA Katsunori <foozy@lares.dti.ne.jp> and others
#
# 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 errno

from . import (
    encoding,
)

def mayhavepending(root):
    '''return whether 'root' may have pending changes, which are
    visible to this process.
    '''
    return root == encoding.environ.get('HG_PENDING')

def trypending(root, vfs, filename, **kwargs):
    '''Open  file to be read according to HG_PENDING environment variable

    This opens '.pending' of specified 'filename' only when HG_PENDING
    is equal to 'root'.

    This returns '(fp, is_pending_opened)' tuple.
    '''
    if mayhavepending(root):
        try:
            return (vfs('%s.pending' % filename, **kwargs), True)
        except IOError as inst:
            if inst.errno != errno.ENOENT:
                raise
    return (vfs(filename, **kwargs), False)