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Differential D2682

[PoC] changegroup: delete obs markers when applying changegroup
Needs RevisionPublic

Authored by indygreg on Mar 4 2018, 7:43 PM.

Details

Reviewers
baymax
Group Reviewers
hg-reviewers
Summary

In local-only obsolescence mode, our short-term hack to unhide a
changeset is to delete obsolescence markers causing it to be hidden.
We need to do this every time a changeset is introduced into the
repository.

I was hoping we could implement the unhide logic once, around
transaction close time. However, it appears that we'll need to
teach every mechanism that introduces changesets to unhide
changesets because of interaction between those mechanisms and
visibility. For example, changegroup application no-ops on incoming
changesets that are present but hidden. The code that scans for
"new" changesets is based on changesets between the old and new
changelog length. Since the unhidden changeset is possibly older
than the old changelog length, we need to either track unhides
explicitly or deal with them specially.

This commit teaches changegroup application to record which changesets
are in the incoming changegroup so it can scan for relevant
obsolescence markers after changegroup applications and delete
their markers.

I'm not convinced this is the best approach to the problem. But it's
a start.

Diff Detail

Repository
rHG Mercurial
Lint
Lint Skipped
Unit
Unit Tests Skipped

Event Timeline

indygreg created this revision.Mar 4 2018, 7:43 PM
baymax requested changes to this revision.Jan 24 2020, 12:33 PM

There seems to have been no activities on this Diff for the past 3 Months.

By policy, we are automatically moving it out of the need-review state.

Please, move it back to need-review without hesitation if this diff should still be discussed.

:baymax:need-review-idle:

This revision now requires changes to proceed.Jan 24 2020, 12:33 PM

Revision Contents
Changeset List

Diff 6640

mercurial/changegroup.py

nullrev, nullrev,
short, short,
) )
from . import ( from . import (
dagutil, dagutil,
error, error,
mdiff, mdiff,
obsolete,
phases, phases,
pycompat, pycompat,
util, util,
) )
_CHANGEGROUPV1_DELTA_HEADER = "20s20s20s20s" _CHANGEGROUPV1_DELTA_HEADER = "20s20s20s20s"
_CHANGEGROUPV2_DELTA_HEADER = "20s20s20s20s20s" _CHANGEGROUPV2_DELTA_HEADER = "20s20s20s20s20s"
_CHANGEGROUPV3_DELTA_HEADER = ">20s20s20s20s20sH" _CHANGEGROUPV3_DELTA_HEADER = ">20s20s20s20s20sH"
Return an integer summarizing the change to this repo: Return an integer summarizing the change to this repo:
- nothing changed or no source: 0 - nothing changed or no source: 0
- more heads than before: 1+added heads (2..n) - more heads than before: 1+added heads (2..n)
- fewer heads than before: -1-removed heads (-2..-n) - fewer heads than before: -1-removed heads (-2..-n)
- number of heads stays the same: 1 - number of heads stays the same: 1
""" """
repo = repo.unfiltered() repo = repo.unfiltered()
incomingnodes = set()
localonlyobs = obsolete.getoptions(repo)[obsolete.localonlymodeopt]
def csmap(x): def csmap(x):
# Don't bother tracking if we don't do anything with data.
if localonlyobs:
incomingnodes.add(x)
repo.ui.debug("add changeset %s\n" % short(x)) repo.ui.debug("add changeset %s\n" % short(x))
return len(cl) return len(cl)
def revmap(x): def revmap(x):
return cl.rev(x) return cl.rev(x)
changesets = files = revisions = 0 changesets = files = revisions = 0
def onchangelog(cl, node): def onchangelog(cl, node):
efiles.update(cl.readfiles(node)) efiles.update(cl.readfiles(node))
self.changelogheader() self.changelogheader()
deltas = self.deltaiter() deltas = self.deltaiter()
cgnodes = cl.addgroup(deltas, csmap, trp, addrevisioncb=onchangelog) cgnodes = cl.addgroup(deltas, csmap, trp, addrevisioncb=onchangelog)
efiles = len(efiles) efiles = len(efiles)
# TODO do we need to invalidate visibility caches when we
# remove markers?
if localonlyobs and incomingnodes:
indices = [i for i, t in enumerate(repo.obsstore._all)
if t[0] in incomingnodes]
if indices:
from . import repair
# TODO is # markers == # unhidden changesets?
repo.ui.status(_('unhiding %d changesets\n') % len(indices))
repair.deleteobsmarkers(repo.obsstore, indices)
if not cgnodes: if not cgnodes:
repo.ui.develwarn('applied empty changegroup', repo.ui.develwarn('applied empty changegroup',
config='warn-empty-changegroup') config='warn-empty-changegroup')
clend = len(cl) clend = len(cl)
changesets = clend - clstart changesets = clend - clstart
repo.ui.progress(_('changesets'), None) repo.ui.progress(_('changesets'), None)
self.callback = None self.callback = None

tests/test-amend.t

#if obsstore-on #if obsstore-on
$ cd .. $ cd ..
$ cp -r repo1 repo1-unbundle-backup $ cp -r repo1 repo1-unbundle-backup
$ cd repo1-unbundle-backup $ cd repo1-unbundle-backup
$ hg unbundle .hg/strip-backup/112478962961-7e959a55-amend.hg $ hg unbundle .hg/strip-backup/112478962961-7e959a55-amend.hg
adding changesets adding changesets
unhiding 1 changesets
adding manifests adding manifests
adding file changes adding file changes
added 0 changesets with 0 changes to 1 files added 0 changesets with 0 changes to 1 files
(run 'hg update' to get a working copy) (run 'hg update' to get a working copy)
TODO obsmarker should be deleted, both versions should be visible
$ hg debugobsolete $ hg debugobsolete
112478962961147124edd43549aedd1a335e44bf be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}
$ hg log -G $ hg log -G
@ changeset: 2:be169c7e8dbe @ changeset: 2:be169c7e8dbe
| tag: tip | tag: tip
| parent: 0:426bada5c675 | parent: 0:426bada5c675
| user: test | user: test
| date: Thu Jan 01 00:00:00 1970 +0000 | date: Thu Jan 01 00:00:00 1970 +0000
| summary: B | summary: B
| |
| x changeset: 1:112478962961 | o changeset: 1:112478962961
|/ tag: B |/ tag: B
| user: test | user: test
| date: Thu Jan 01 00:00:00 1970 +0000 | date: Thu Jan 01 00:00:00 1970 +0000
| obsolete: rewritten using amend as 2:be169c7e8dbe
| summary: B | summary: B
| |
o changeset: 0:426bada5c675 o changeset: 0:426bada5c675
tag: A tag: A
user: test user: test
date: Thu Jan 01 00:00:00 1970 +0000 date: Thu Jan 01 00:00:00 1970 +0000
summary: A summary: A