mercurial/txnutil.py

subrepo: run the repo decoders when archiving

The decoders were already run by default for the main repo, so this seemed like
an oversight.

The extdiff extension has been using 'archive' since 68822b7cdd01 to support -S,
and a colleague noticed that after diffing, making changes, and closing it, the
line endings were wrong for the diff-tool modified files in the subrepository.
(Files in the parent repo were correct, with the same .hgeol settings.)  The
editor (Visual Studio in this case) reloads the file, but doesn't notice the EOL
change.  It still adds new lines with the original EOL setting, and the file
ends up inconsistent.

Without this change, the first file `cat`d in the test prints '\r (esc)' EOL,
but the second doesn't on Windows or Linux.

# 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)