view mercurial/txnutil.py @ 40386:4a81d82474e9

lfs: consult the narrow matcher when extracting pointers from ctx (issue5794)

I added a testcase for lfs to all narrow tests, and the following failed:

    test-narrow-acl.t
    test-narrow-exchange.t
    test-narrow-patterns.t
    test-narrow-strip.t
    test-narrow-trackedcmd.t
    test-narrow-widen.t
    test-narrow.t

The first two still have errors in the pretxnchangegroup on clone and (receiving
a) push, which I'm still looking into (4d63f3bc1e1a fixed something in this area
already).  These two modified tests seem to cover the things that failed in the
remaining narrow tests, i.e. `hg tracked` and `hg strip`, so I didn't bother
enabling the testcases elsewhere.  Maybe we should, but it's 68 tests total.

# 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)