view mercurial/dirstateguard.py @ 44746:c36a3fcfc36b stable

upgrade: properly filter action depending on planned work

The `determineactions` function filters out deficiency that are not scheduled to
be fixed by the target repository configuration. However it only did so for
requirement we currently support, letting other actions for unsupported
requirement through even if the target repo configuration did not request it.

As a result the output of the command was easily polluted by experimental
feature with no upgrade support.

We rework the code to still filter out requirement based action without the
faulty filtering.

Differential Revision: https://phab.mercurial-scm.org/D8427

# dirstateguard.py - class to allow restoring dirstate after failure
#
# Copyright 2005-2007 Matt Mackall <[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 __future__ import absolute_import

from .i18n import _

from . import (
    error,
    narrowspec,
    util,
)


class dirstateguard(util.transactional):
    '''Restore dirstate at unexpected failure.

    At the construction, this class does:

    - write current ``repo.dirstate`` out, and
    - save ``.hg/dirstate`` into the backup file

    This restores ``.hg/dirstate`` from backup file, if ``release()``
    is invoked before ``close()``.

    This just removes the backup file at ``close()`` before ``release()``.
    '''

    def __init__(self, repo, name):
        self._repo = repo
        self._active = False
        self._closed = False
        self._backupname = b'dirstate.backup.%s.%d' % (name, id(self))
        self._narrowspecbackupname = b'narrowspec.backup.%s.%d' % (
            name,
            id(self),
        )
        repo.dirstate.savebackup(repo.currenttransaction(), self._backupname)
        narrowspec.savewcbackup(repo, self._narrowspecbackupname)
        self._active = True

    def __del__(self):
        if self._active:  # still active
            # this may occur, even if this class is used correctly:
            # for example, releasing other resources like transaction
            # may raise exception before ``dirstateguard.release`` in
            # ``release(tr, ....)``.
            self._abort()

    def close(self):
        if not self._active:  # already inactivated
            msg = (
                _(b"can't close already inactivated backup: %s")
                % self._backupname
            )
            raise error.Abort(msg)

        self._repo.dirstate.clearbackup(
            self._repo.currenttransaction(), self._backupname
        )
        narrowspec.clearwcbackup(self._repo, self._narrowspecbackupname)
        self._active = False
        self._closed = True

    def _abort(self):
        narrowspec.restorewcbackup(self._repo, self._narrowspecbackupname)
        self._repo.dirstate.restorebackup(
            self._repo.currenttransaction(), self._backupname
        )
        self._active = False

    def release(self):
        if not self._closed:
            if not self._active:  # already inactivated
                msg = (
                    _(b"can't release already inactivated backup: %s")
                    % self._backupname
                )
                raise error.Abort(msg)
            self._abort()