--- a/mercurial/dirstateguard.py	Thu Feb 16 00:14:21 2023 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,96 +0,0 @@
-# dirstateguard.py - class to allow restoring dirstate after failure
-#
-# Copyright 2005-2007 Olivia Mackall <olivia@selenic.com>
-#
-# This software may be used and distributed according to the terms of the
-# GNU General Public License version 2 or any later version.
-
-
-import os
-from .i18n import _
-
-from . import (
-    error,
-    narrowspec,
-    requirements,
-    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
-
-        def getname(prefix):
-            fd, fname = repo.vfs.mkstemp(prefix=prefix)
-            os.close(fd)
-            return fname
-
-        self._backupname = getname(b'dirstate.backup.%s.' % name)
-        repo.dirstate.savebackup(repo.currenttransaction(), self._backupname)
-        # Don't make this the empty string, things may join it with stuff and
-        # blindly try to unlink it, which could be bad.
-        self._narrowspecbackupname = None
-        if requirements.NARROW_REQUIREMENT in repo.requirements:
-            self._narrowspecbackupname = getname(
-                b'narrowspec.backup.%s.' % name
-            )
-            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
-        )
-        if self._narrowspecbackupname:
-            narrowspec.clearwcbackup(self._repo, self._narrowspecbackupname)
-        self._active = False
-        self._closed = True
-
-    def _abort(self):
-        if self._narrowspecbackupname:
-            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()