mercurial/txnutil.py

status: handle more node indicators in buildstatus

There are several different node markers that indicate different working copy
states. The context._buildstatus function was only handling one of them, and
this patch makes it handle all of them (falling back to file content comparisons
when in one of these states).

This affects a future patch where we get rid of context._manifestmatches as part
of getting rid of manifest.matches(). context._manifestmatches is currently
hacky in that it uses the newnodeid for all added and modified files, which is
why the current newnodeid check is sufficient. When we get rid of this function
and use the normal manifest.diff function, we start to see the other indicators
in the nodes, so they need to be handled or else the tests fail.

# 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)