Mercurial > hg
view mercurial/dirstateguard.py @ 48061:060cd909439f
dirstate: drop all logic around the "non-normal" sets
The dirstate has a lot of code to compute a set of all "non-normal" and
"from_other_parent" entries.
This is all used in one, unique, location, when `setparent` is called and moved
from a merge to a non merge. At that time, any "merge related" information has
to be dropped. This is mostly useful for command like `graft` or `shelve` that
move to a single-parent state -before- the commit. Otherwise the commit will
already have removed all traces of the merge information in the dirstate (e.g.
for a regular merges).
The bookkeeping for these sets is quite invasive. And it seems simpler to just
drop it and do the full computation in the single location where we actually
use it (since we have to do the computation at least once anyway).
This simplify the code a lot, and clarify why this kind of computation is
needed.
The possible drawback compared to the previous code are:
- if the operation happens in a loop, we will end up doing it multiple time,
- the C code to detect entry of interest have been dropped, for now. It will be
re-introduced later, with a processing code directly in C for even faster
operation.
Differential Revision: https://phab.mercurial-scm.org/D11507
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 28 Sep 2021 20:05:37 +0200 |
parents | 222a42ac5b2d |
children | 6000f5b25c9b |
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# 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. from __future__ import absolute_import 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()