##// END OF EJS Templates
error: introduce StorageError...
error: introduce StorageError Errors in revlogs are often represented by RevlogError. It's fine for revlogs to raise a revlog-specific exception. But in the context of multiple storage backends, it doesn't make sense to be throwing or catching an exception with "revlog" in its name when revlogs may not even be in play. This commit introduces a new generic StorageError type for representing errors in the storage layer. RevlogError is an instance of this type. Interface documentation and tests referencing RevlogError has been updated to specify StorageError should be used. .. api:: ``error.StorageError`` has been introduced to represent errors in storage. It should be used in place of ``error.RevlogError`` unless the error is known to come from a revlog. Differential Revision: https://phab.mercurial-scm.org/D4654

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dirstateguard.py
75 lines | 2.6 KiB | text/x-python | PythonLexer
# dirstateguard.py - class to allow restoring dirstate after failure
#
# Copyright 2005-2007 Matt Mackall <mpm@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.
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 = 'dirstate.backup.%s.%d' % (name, id(self))
self._narrowspecbackupname = ('narrowspec.backup.%s.%d' %
(name, id(self)))
repo.dirstate.savebackup(repo.currenttransaction(), self._backupname)
narrowspec.savebackup(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 = (_("can't close already inactivated backup: %s")
% self._backupname)
raise error.Abort(msg)
self._repo.dirstate.clearbackup(self._repo.currenttransaction(),
self._backupname)
narrowspec.clearbackup(self._repo, self._narrowspecbackupname)
self._active = False
self._closed = True
def _abort(self):
narrowspec.restorebackup(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 = (_("can't release already inactivated backup: %s")
% self._backupname)
raise error.Abort(msg)
self._abort()