mercurial/txnutil.py

tests: add commit hashes to log commands in rebase tests

Commit hashes are a useful way to ensure the content of commits made in the
tests are not changing, even if we don't query every aspect of every commit.
(And some properties, like extras, are rarely printed at all.)

Many of the rebase log -G calls didn't show hashes; by adding hashes to places
that weren't showing them we can help protect those tests from unwanted
changes.

Differential Revision: https://phab.mercurial-scm.org/D1650

# txnutil.py - transaction related utilities
#
#  Copyright FUJIWARA Katsunori <[e-mail]> 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)