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Differential D2681

[PoC] scmutil: support local only obsolescence
Needs RevisionPublic

Authored by indygreg on Mar 4 2018, 7:42 PM.

Details

Reviewers
baymax
Group Reviewers
hg-reviewers
Summary

Now that we have a config option for enabling local-only obsolescence,
it is time to do something with it.

This commit teaches cleanupnodes() - which is called after rewrite
operations - to handle local only obsolescence mode.

In this mode, we create a backup bundle of the obsoleted changesets -
just like what happens if obsolescence is disabled. But we don't strip
the repo: we keep the original changesets around in a non-visible state.

The new code verifies that no unstable changesets are introduced in
local-only obsolescence mode.

The new code hackily only runs if the action is "amend." The intent
is to make this conditional only on the feature option. However,
doing that would have significant test fallout. So we limit to "amend"
for now.

TODO:

  • Better test coverage (I think the "(testcase !)" syntax might be subtly wrong by flagging output as optional and not required).
  • Delete obsolescence markers when we pull and unbundle from the bundle.
  • Support pulling locally-hidden heads.

Diff Detail

Repository
rHG Mercurial
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Unit
Unit Tests Skipped

Event Timeline

indygreg created this revision.Mar 4 2018, 7:42 PM
mharbison72 added a subscriber: mharbison72.Mar 4 2018, 9:22 PM

re: the "(testcase !)" syntax- I agree that it would be better if "(false !)" means the line is *not* present, instead of optional.

I made an attempt to do that, but somehow I came up with a test in test-run-tests.t that failed there, but the exact same test ran fine in another *.t. I wondered if it was a case of run-tests.py processing it for a test inside test-run-tests.t, and then the main instance of run-tests.py re-processing it. If I can find that code, I can post it if you think it might be useful. But I've long forgotten the nuance in that code.

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 6639

mercurial/scmutil.py

for name in oldbmarks: for name in oldbmarks:
bmarkchanges.append((name, newnode)) bmarkchanges.append((name, newnode))
for b in bookmarks.divergent2delete(repo, deletenodes, name): for b in bookmarks.divergent2delete(repo, deletenodes, name):
bmarkchanges.append((b, None)) bmarkchanges.append((b, None))
if bmarkchanges: if bmarkchanges:
bmarks.applychanges(repo, tr, bmarkchanges) bmarks.applychanges(repo, tr, bmarkchanges)
# Obsolete or strip nodes # We either create obsolescence markers or strip.
if obsolete.isenabled(repo, obsolete.createmarkersopt): # If we create markers and we're in local only mode, we create a backup
# bundle.
obsopts = obsolete.getoptions(repo)
if (obsopts[obsolete.createmarkersopt] or
obsopts[obsolete.localonlymodeopt]):
# If a node is already obsoleted, and we want to obsolete it # If a node is already obsoleted, and we want to obsolete it
# without a successor, skip that obssolete request since it's # without a successor, skip that obssolete request since it's
# unnecessary. That's the "if s or not isobs(n)" check below. # unnecessary. That's the "if s or not isobs(n)" check below.
# Also sort the node in topology order, that might be useful for # Also sort the node in topology order, that might be useful for
# some obsstore logic. # some obsstore logic.
# NOTE: the filtering and sorting might belong to createmarkers. # NOTE: the filtering and sorting might belong to createmarkers.
isobs = unfi.obsstore.successors.__contains__ isobs = unfi.obsstore.successors.__contains__
torev = unfi.changelog.rev torev = unfi.changelog.rev
sortfunc = lambda ns: torev(ns[0]) sortfunc = lambda ns: torev(ns[0])
rels = [(unfi[n], tuple(unfi[m] for m in s)) rels = [(unfi[n], tuple(unfi[m] for m in s))
for n, s in sorted(replacements.items(), key=sortfunc) for n, s in sorted(replacements.items(), key=sortfunc)
if s or not isobs(n)] if s or not isobs(n)]
if rels: if rels:
# For now, explicitly limit which operations opt in to this
# behavior. Also, we need to run this code before markers are
# created, otherwise visibility changes would impact operation.
if operation == 'amend' and obsopts[obsolete.localonlymodeopt]:
from . import repair # avoid import cycle
# We should not be creating unstable changesets in
# local only mode. Verify that.
oldrevs = set(torev(n) for n in replacements)
tobundle = set(repo.revs('%ld::', oldrevs))
if len(tobundle) > len(oldrevs):
raise error.Abort(_('cannot create unstable changesets '
'in local-only obsolescence mode'))
roots = set(ctx.node()
for ctx in repo.set('roots(%ld)', oldrevs))
heads = set(ctx.node()
for ctx in repo.set('heads(%ld)', oldrevs))
backupfile = repair.backupbundle(
repo, roots, heads, repo[min(roots)].node(), operation)
repo.ui.status(_('saved backup bundle to %s\n') %
repo.vfs.join(backupfile))
repo.ui.log('backupbundle', 'saved backup bundle to %s\n',
repo.vfs.join(backupfile))
obsolete.createmarkers(repo, rels, operation=operation, obsolete.createmarkers(repo, rels, operation=operation,
metadata=metadata) metadata=metadata)
else: else:
from . import repair # avoid import cycle from . import repair # avoid import cycle
tostrip = list(replacements) tostrip = list(replacements)
if tostrip: if tostrip:
repair.delayedstrip(repo.ui, repo, tostrip, operation) repair.delayedstrip(repo.ui, repo, tostrip, operation)
def addremove(repo, matcher, prefix, opts=None, dry_run=None, similarity=None): def addremove(repo, matcher, prefix, opts=None, dry_run=None, similarity=None):
if opts is None: if opts is None:

tests/test-amend.t

#testcases obsstore-off obsstore-on #testcases obsstore-off obsstore-on evolution-on
$ cat << EOF >> $HGRCPATH $ cat << EOF >> $HGRCPATH
> [extensions] > [extensions]
> amend= > amend=
> debugdrawdag=$TESTDIR/drawdag.py > debugdrawdag=$TESTDIR/drawdag.py
> [diff] > [diff]
> git=1 > git=1
> EOF > EOF
#if obsstore-on #if obsstore-off
$ cat << EOF >> $HGRCPATH
> [ui]
> localobsolescence = false
> EOF
#endif
#if evolution-on
$ cat << EOF >> $HGRCPATH $ cat << EOF >> $HGRCPATH
> [experimental] > [experimental]
> evolution.createmarkers=True > evolution.createmarkers = true
> EOF > EOF
#endif #endif
Basic amend Basic amend
$ hg init repo1 $ hg init repo1
$ cd repo1 $ cd repo1
$ hg debugdrawdag <<'EOS' $ hg debugdrawdag <<'EOS'
diff --git a/A b/A diff --git a/A b/A
new file mode 100644 new file mode 100644
--- /dev/null --- /dev/null
+++ b/A +++ b/A
@@ -0,0 +1,1 @@ @@ -0,0 +1,1 @@
+A +A
\ No newline at end of file \ No newline at end of file
$ hg debugobsolete
#else #else
$ hg log -p -G --hidden -T '{rev} {node|short} {desc}\n' $ hg log -p -G --hidden -T '{rev} {node|short} {desc}\n'
@ 2 be169c7e8dbe B @ 2 be169c7e8dbe B
| diff --git a/B b/B | diff --git a/B b/B
| new file mode 100644 | new file mode 100644
| --- /dev/null | --- /dev/null
| +++ b/B | +++ b/B
| @@ -0,0 +1,1 @@ | @@ -0,0 +1,1 @@
diff --git a/A b/A diff --git a/A b/A
new file mode 100644 new file mode 100644
--- /dev/null --- /dev/null
+++ b/A +++ b/A
@@ -0,0 +1,1 @@ @@ -0,0 +1,1 @@
+A +A
\ No newline at end of file \ No newline at end of file
$ hg debugobsolete
112478962961147124edd43549aedd1a335e44bf be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}
#endif
Unbundling from backup bundle restores visibility
#if obsstore-on
$ cd ..
$ cp -r repo1 repo1-unbundle-backup
$ cd repo1-unbundle-backup
$ hg unbundle .hg/strip-backup/112478962961-7e959a55-amend.hg
adding changesets
adding manifests
adding file changes
added 0 changesets with 0 changes to 1 files
(run 'hg update' to get a working copy)
TODO obsmarker should be deleted, both versions should be visible
$ hg debugobsolete
112478962961147124edd43549aedd1a335e44bf be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}
$ hg log -G
@ changeset: 2:be169c7e8dbe
| tag: tip
| parent: 0:426bada5c675
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B
|
| x changeset: 1:112478962961
|/ tag: B
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| obsolete: rewritten using amend as 2:be169c7e8dbe
| summary: B
|
o changeset: 0:426bada5c675
tag: A
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: A
$ cd ..
Pulling from a backup bundle restores visibility
$ cp -r repo1 repo1-pull-backup
$ cd repo1-pull-backup
$ hg pull .hg/strip-backup/112478962961-7e959a55-amend.hg
pulling from .hg/strip-backup/112478962961-7e959a55-amend.hg
searching for changes
no changes found
TODO obsmarker should be deleted, both versions should be visible
$ hg debugobsolete
112478962961147124edd43549aedd1a335e44bf be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}
$ hg log -G
@ changeset: 2:be169c7e8dbe
| tag: tip
| parent: 0:426bada5c675
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B
|
| x changeset: 1:112478962961
|/ tag: B
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| obsolete: rewritten using amend as 2:be169c7e8dbe
| summary: B
|
o changeset: 0:426bada5c675
tag: A
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: A
$ cd ../repo1
#endif #endif
Nothing changed Nothing changed
$ hg amend $ hg amend
nothing changed nothing changed
[1] [1]
> EOS > EOS
$ hg update -q B $ hg update -q B
$ echo 2 >> B $ echo 2 >> B
$ hg amend $ hg amend
abort: cannot amend changeset with children abort: cannot amend changeset with children
[255] [255]
#if obsstore-on #if evolution-on
With allowunstable, amend could work in the middle of a stack With allowunstable, amend could work in the middle of a stack
$ cat >> $HGRCPATH <<EOF $ cat >> $HGRCPATH <<EOF
> [experimental] > [experimental]
> evolution.createmarkers=True > evolution.createmarkers=True
> evolution.allowunstable=True > evolution.allowunstable=True
> EOF > EOF