view mercurial/txnutil.py @ 35044:71e63fe6b1ab

py3: handle keyword arguments correctly in hgext/patchbomb.py

The keys of keyword arguments must be str on Python 3 which is unicode. This
patch make sure we pass keyword arguments with keys are str everywhere in this
file and access the keys depending on whether they are bytes or str.

This patch uses pycompat.{byteskwargs|strkwargs} and somewhere it also added r''
to prevent transformer from adding a b'' over there.

Differential Revision: https://phab.mercurial-scm.org/D974

# 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)