On 11/21/2016 09:50 PM, Augie Fackler wrote:
On Sat, Nov 05, 2016 at 09:40:21PM -0700, Gregory Szorc wrote:# HG changeset patch # User Gregory Szorc <gregory.sz...@gmail.com> # Date 1478394961 25200 # Sat Nov 05 18:16:01 2016 -0700 # Node ID b768004ef2db9c2e6dd267997e9e0c011f1b732a # Parent 7518e68e2f8276e85fb68174b3055a9dd16c665d repair: obtain and validate requirements for upgraded repo Not all existing repositories can be upgraded. Not all requirements are supported in new repositories. Some transitions between repository requirements (notably removing a requirement) are not supported. This patch adds code for validating that the requirements transition for repository upgrades is acceptable and aborts if it isn't. Functionality is split into various functions to give extensions an opportunity to monkeypatch. diff --git a/mercurial/repair.py b/mercurial/repair.py --- a/mercurial/repair.py +++ b/mercurial/repair.py @@ -401,6 +401,85 @@ def upgradefinddeficiencies(repo): return l, actions +def upgradesupporteddestrequirements(repo): + """Obtain requirements that upgrade supports in the destination. + + Extensions should monkeypatch this to add their custom requirements. + """ + return set([ + 'dotencode', + 'fncache', + 'generaldelta', + 'manifestv2', + 'revlogv1', + 'store', + 'treemanifest', + ]) + +def upgraderequiredsourcerequirements(repo): + """Obtain requirements that must be present in the source repository.""" + return set([ + 'revlogv1', + 'store', + ]) + +def upgradeallowednewrequirements(repo): + """Obtain requirements that can be added to a repository. + + This is used to disallow proposed requirements from being added when + they weren't present before. + + We use a whitelist of allowed requirement additions instead of a + blacklist of known bad additions because the whitelist approach is + safer and will prevent future, unknown requirements from accidentally + being added. + """ + return set([ + 'dotencode', + 'fncache', + 'generaldelta', + ]) + +def upgradereporequirements(repo): + """Obtain and validate requirements for repository after upgrade. + + Should raise ``Abort`` if existing or new requirements aren't sufficient. + """ + # Avoid cycle: cmdutil -> repair -> localrepo -> cmdutil + from . import localrepoIt looks like there should be relatively minimal work to break the dep from localrepo to cmdutil. That dependency definitely looks suspect to me (dirstateguard seems like it should be in dirstate.py just from the name, and checkunresolved probably belongs in mergemod? or dirstate?) Not a blocker for this series, but wanted to bring this up. I dream of a future without any imports hidden inside a function to avoid cycles.+ + existing = repo.requirements + + missingreqs = upgraderequiredsourcerequirements(repo) - existing + if missingreqs: + raise error.Abort(_('cannot upgrade repository; requirement ' + 'missing: %s') % ', '.join(sorted(missingreqs))) + + createreqs = localrepo.newreporequirements(repo) + + # This might be overly restrictive. It is definitely safer to enforce this + # as it prevents unwanted deletion of requirements.I can't think of a world where we'd want to allow discarding requirements on upgrade.
If we come to a point where we can upgrade only part of the requirement, (cf my comment on 4.0) this would be useful.
+ removedreqs = existing - createreqs + if removedreqs: + raise error.Abort(_('cannot upgrade repository; requirement would ' + 'be removed: %s') % ', '.join(sorted(removedreqs))) + + unsupportedreqs = createreqs - upgradesupporteddestrequirements(repo) + if unsupportedreqs: + raise error.Abort(_('cannot upgrade repository; new requirement not ' + 'supported: %s') % + ', '.join(sorted(unsupportedreqs))) + + # Alternatively, we could silently remove the disallowed requirement + # instead of aborting. + noaddreqs = createreqs - existing - upgradeallowednewrequirements(repo) + if noaddreqs: + raise error.Abort(_('cannot upgrade repository; proposed new ' + 'requirement cannot be added: %s') % + ', '.join(sorted(noaddreqs))) + + return createreqs + def upgraderepo(ui, repo, dryrun=False): """Upgrade a repository in place.""" repo = repo.unfiltered() @@ -414,3 +493,17 @@ def upgraderepo(ui, repo, dryrun=False): ui.write('* %s\n' % d) else: ui.write(_('no obvious deficiencies found in existing repository\n')) + + ui.write(_('\n')) + ui.write(_('checking repository requirements...\n')) + + newreqs = upgradereporequirements(repo) + # We don't drop requirements. + assert not len(repo.requirements - newreqs) + + ui.write(_('preserving repository requirements: %s\n') % + ', '.join(sorted(repo.requirements & newreqs))) + if newreqs - repo.requirements: + ui.write(_('adding repository requirements: %s\n') % + ', '.join(sorted(newreqs - repo.requirements))) +[...] _______________________________________________ Mercurial-devel mailing list Mercurial-devel@mercurial-scm.org https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel
-- Pierre-Yves David _______________________________________________ Mercurial-devel mailing list Mercurial-devel@mercurial-scm.org https://www.mercurial-scm.org/mailman/listinfo/mercurial-devel
