Mercurial > hg
view hgext/strip.py @ 32697:19b9fc40cc51
revlog: skeleton support for version 2 revlogs
There are a number of improvements we want to make to revlogs
that will require a new version - version 2. It is unclear what the
full set of improvements will be or when we'll be done with them.
What I do know is that the process will likely take longer than a
single release, will require input from various stakeholders to
evaluate changes, and will have many contentious debates and
bikeshedding.
It is unrealistic to develop revlog version 2 up front: there
are just too many uncertainties that we won't know until things
are implemented and experiments are run. Some changes will also
be invasive and prone to bit rot, so sitting on dozens of patches
is not practical.
This commit introduces skeleton support for version 2 revlogs in
a way that is flexible and not bound by backwards compatibility
concerns.
An experimental repo requirement for denoting revlog v2 has been
added. The requirement string has a sub-version component to it.
This will allow us to declare multiple requirements in the course
of developing revlog v2. Whenever we change the in-development
revlog v2 format, we can tweak the string, creating a new
requirement and locking out old clients. This will allow us to
make as many backwards incompatible changes and experiments to
revlog v2 as we want. In other words, we can land code and make
meaningful progress towards revlog v2 while still maintaining
extreme format flexibility up until the point we freeze the
format and remove the experimental labels.
To enable the new repo requirement, you must supply an experimental
and undocumented config option. But not just any boolean flag
will do: you need to explicitly use a value that no sane person
should ever type. This is an additional guard against enabling
revlog v2 on an installation it shouldn't be enabled on. The
specific scenario I'm trying to prevent is say a user with a
4.4 client with a frozen format enabling the option but then
downgrading to 4.3 and accidentally creating repos with an
outdated and unsupported repo format. Requiring a "challenge"
string should prevent this.
Because the format is not yet finalized and I don't want to take
any chances, revlog v2's version is currently 0xDEAD. I figure
squatting on a value we're likely never to use as an actual revlog
version to mean "internal testing only" is acceptable. And
"dead" is easily recognized as something meaningful.
There is a bunch of cleanup that is needed before work on revlog
v2 begins in earnest. I plan on doing that work once this patch
is accepted and we're comfortable with the idea of starting down
this path.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 19 May 2017 20:29:11 -0700 |
parents | 46ba2cdda476 |
children | 799db2af824c |
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"""strip changesets and their descendants from history This extension allows you to strip changesets and all their descendants from the repository. See the command help for details. """ from __future__ import absolute_import from mercurial.i18n import _ from mercurial import ( bookmarks as bookmarksmod, cmdutil, error, hg, lock as lockmod, merge, node as nodemod, registrar, repair, scmutil, util, ) nullid = nodemod.nullid release = lockmod.release cmdtable = {} command = registrar.command(cmdtable) # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should # be specifying the version(s) of Mercurial they are tested with, or # leave the attribute unspecified. testedwith = 'ships-with-hg-core' def checksubstate(repo, baserev=None): '''return list of subrepos at a different revision than substate. Abort if any subrepos have uncommitted changes.''' inclsubs = [] wctx = repo[None] if baserev: bctx = repo[baserev] else: bctx = wctx.parents()[0] for s in sorted(wctx.substate): wctx.sub(s).bailifchanged(True) if s not in bctx.substate or bctx.sub(s).dirty(): inclsubs.append(s) return inclsubs def checklocalchanges(repo, force=False, excsuffix=''): cmdutil.checkunfinished(repo) s = repo.status() if not force: if s.modified or s.added or s.removed or s.deleted: _("local changes found") # i18n tool detection raise error.Abort(_("local changes found" + excsuffix)) if checksubstate(repo): _("local changed subrepos found") # i18n tool detection raise error.Abort(_("local changed subrepos found" + excsuffix)) return s def strip(ui, repo, revs, update=True, backup=True, force=None, bookmarks=None): wlock = lock = None try: wlock = repo.wlock() lock = repo.lock() if update: checklocalchanges(repo, force=force) urev, p2 = repo.changelog.parents(revs[0]) if (util.safehasattr(repo, 'mq') and p2 != nullid and p2 in [x.node for x in repo.mq.applied]): urev = p2 hg.clean(repo, urev) repo.dirstate.write(repo.currenttransaction()) repair.strip(ui, repo, revs, backup) repomarks = repo._bookmarks if bookmarks: with repo.transaction('strip') as tr: if repo._activebookmark in bookmarks: bookmarksmod.deactivate(repo) for bookmark in bookmarks: del repomarks[bookmark] repomarks.recordchange(tr) for bookmark in sorted(bookmarks): ui.write(_("bookmark '%s' deleted\n") % bookmark) finally: release(lock, wlock) @command("strip", [ ('r', 'rev', [], _('strip specified revision (optional, ' 'can specify revisions without this ' 'option)'), _('REV')), ('f', 'force', None, _('force removal of changesets, discard ' 'uncommitted changes (no backup)')), ('', 'no-backup', None, _('no backups')), ('', 'nobackup', None, _('no backups (DEPRECATED)')), ('n', '', None, _('ignored (DEPRECATED)')), ('k', 'keep', None, _("do not modify working directory during " "strip")), ('B', 'bookmark', [], _("remove revs only reachable from given" " bookmark"))], _('hg strip [-k] [-f] [-B bookmark] [-r] REV...')) def stripcmd(ui, repo, *revs, **opts): """strip changesets and all their descendants from the repository The strip command removes the specified changesets and all their descendants. If the working directory has uncommitted changes, the operation is aborted unless the --force flag is supplied, in which case changes will be discarded. If a parent of the working directory is stripped, then the working directory will automatically be updated to the most recent available ancestor of the stripped parent after the operation completes. Any stripped changesets are stored in ``.hg/strip-backup`` as a bundle (see :hg:`help bundle` and :hg:`help unbundle`). They can be restored by running :hg:`unbundle .hg/strip-backup/BUNDLE`, where BUNDLE is the bundle file created by the strip. Note that the local revision numbers will in general be different after the restore. Use the --no-backup option to discard the backup bundle once the operation completes. Strip is not a history-rewriting operation and can be used on changesets in the public phase. But if the stripped changesets have been pushed to a remote repository you will likely pull them again. Return 0 on success. """ backup = True if opts.get('no_backup') or opts.get('nobackup'): backup = False cl = repo.changelog revs = list(revs) + opts.get('rev') revs = set(scmutil.revrange(repo, revs)) with repo.wlock(): bookmarks = set(opts.get('bookmark')) if bookmarks: repomarks = repo._bookmarks if not bookmarks.issubset(repomarks): raise error.Abort(_("bookmark '%s' not found") % ','.join(sorted(bookmarks - set(repomarks.keys())))) # If the requested bookmark is not the only one pointing to a # a revision we have to only delete the bookmark and not strip # anything. revsets cannot detect that case. nodetobookmarks = {} for mark, node in repomarks.iteritems(): nodetobookmarks.setdefault(node, []).append(mark) for marks in nodetobookmarks.values(): if bookmarks.issuperset(marks): rsrevs = repair.stripbmrevset(repo, marks[0]) revs.update(set(rsrevs)) if not revs: lock = tr = None try: lock = repo.lock() tr = repo.transaction('bookmark') for bookmark in bookmarks: del repomarks[bookmark] repomarks.recordchange(tr) tr.close() for bookmark in sorted(bookmarks): ui.write(_("bookmark '%s' deleted\n") % bookmark) finally: release(lock, tr) if not revs: raise error.Abort(_('empty revision set')) descendants = set(cl.descendants(revs)) strippedrevs = revs.union(descendants) roots = revs.difference(descendants) update = False # if one of the wdir parent is stripped we'll need # to update away to an earlier revision for p in repo.dirstate.parents(): if p != nullid and cl.rev(p) in strippedrevs: update = True break rootnodes = set(cl.node(r) for r in roots) q = getattr(repo, 'mq', None) if q is not None and q.applied: # refresh queue state if we're about to strip # applied patches if cl.rev(repo.lookup('qtip')) in strippedrevs: q.applieddirty = True start = 0 end = len(q.applied) for i, statusentry in enumerate(q.applied): if statusentry.node in rootnodes: # if one of the stripped roots is an applied # patch, only part of the queue is stripped start = i break del q.applied[start:end] q.savedirty() revs = sorted(rootnodes) if update and opts.get('keep'): urev, p2 = repo.changelog.parents(revs[0]) if (util.safehasattr(repo, 'mq') and p2 != nullid and p2 in [x.node for x in repo.mq.applied]): urev = p2 uctx = repo[urev] # only reset the dirstate for files that would actually change # between the working context and uctx descendantrevs = repo.revs("%s::." % uctx.rev()) changedfiles = [] for rev in descendantrevs: # blindly reset the files, regardless of what actually changed changedfiles.extend(repo[rev].files()) # reset files that only changed in the dirstate too dirstate = repo.dirstate dirchanges = [f for f in dirstate if dirstate[f] != 'n'] changedfiles.extend(dirchanges) repo.dirstate.rebuild(urev, uctx.manifest(), changedfiles) repo.dirstate.write(repo.currenttransaction()) # clear resolve state merge.mergestate.clean(repo, repo['.'].node()) update = False strip(ui, repo, revs, backup=backup, update=update, force=opts.get('force'), bookmarks=bookmarks) return 0