view mercurial/peer.py @ 24995:0579b0c2ea2b

tryimportone: use dirstateguard instead of beginparentchange/endparentchange

To fix the issue that the recent (in memory) dirstate isn't visible to
external process (e.g. "precommit" hook), a subsequent patch makes
"localrepository.commit()" invoke "dirstate.write()" in it.

This change will make "beginparentchange()" and "endparentchange()" on
dirstate in "cmdutil.tryimportone()" meaningless, because:

  - "dirstate.write()" writes changed data into ".hg/dirstate", but

  - aborting between "beginparentchange()" and "endparentchange()"
    doesn't cause any restoring ".hg/dirstate"

    it just discards changes in memory.

This patch uses "dirstateguard" instead of "beginparentchange()" and
"endparentchange()" in "cmdutil.tryimportone()" to restore
".hg/dirstate" during a failure even if "dirstate.write()" is executed
before a failure.

This patch uses "lockmod.release(dsguard)" instead of
"dsguard.release()", because processing may be aborted before
assignment to "dsguard" , and the "if dsguard" examination for safety is
redundant.

# peer.py - repository base classes for mercurial
#
# Copyright 2005, 2006 Matt Mackall <[e-mail]>
# Copyright 2006 Vadim Gelfer <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from i18n import _
import error

class peerrepository(object):

    def capable(self, name):
        '''tell whether repo supports named capability.
        return False if not supported.
        if boolean capability, return True.
        if string capability, return string.'''
        caps = self._capabilities()
        if name in caps:
            return True
        name_eq = name + '='
        for cap in caps:
            if cap.startswith(name_eq):
                return cap[len(name_eq):]
        return False

    def requirecap(self, name, purpose):
        '''raise an exception if the given capability is not present'''
        if not self.capable(name):
            raise error.CapabilityError(
                _('cannot %s; remote repository does not '
                  'support the %r capability') % (purpose, name))

    def local(self):
        '''return peer as a localrepo, or None'''
        return None

    def peer(self):
        return self

    def canpush(self):
        return True

    def close(self):
        pass