mercurial/txnutil.py
author Pierre-Yves David <pierre-yves.david@octobus.net>
Thu, 03 Feb 2022 18:14:11 +0100
changeset 48716 f1eb77dceb36
parent 45942 89a2afe31e82
child 48875 6000f5b25c9b
permissions -rw-r--r--
narrow: allow merging non-conflicting change outside of the narrow spec We use the mergestate to carry information about these merge action and reprocess them at commit time to apply the necessary update. The dirstate itself is never affected and remains "pure", with content only in the narrow-spec. This file involved in such merge are therefor not listed in `hg status`. The current testing is based on a modification of the previous testing, that refused to do such merges. As a result it is a bit simple and more extensive code and testing testing will have to be introduced later. I am planning to do this extra testing, soon. In addition, this only works for flat manifest. Support for tree manifest will need more work. I am not currently planning to do this work. Differential Revision: https://phab.mercurial-scm.org/D12119

# 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(b'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(b'%s.pending' % filename, **kwargs), True)
        except IOError as inst:
            if inst.errno != errno.ENOENT:
                raise
    return (vfs(filename, **kwargs), False)