hooks: add some test about HGPLAIN setting and hooks
In Mercurial 5.7, hooks are now ran with HGPLAIN set, which is a behavior change
in. I could not find explicit test about it so I am adding one. The next
changesets will introduce more change to help user mitigate the behavior change
when needed.
Differential Revision: https://phab.mercurial-scm.org/D9979
# 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)