mercurial/txnutil.py

tests: unset environment variable P in test-revset2.t (issue6109)

The test tests/test-revset2.t fails the test case

"Test repo.anyrevs with customized revset overrides" (line 1609)

if the environment variable P is set. The test implicitly expects that the
environment, in which it is started, does not export the variable 'P'.

To solve this issue, unset 'P' right before the test commands are run.

Differential Revision: https://phab.mercurial-scm.org/D6195

# 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)