( )⚙ D10272 rebase: drop support for rebaseskipobsolete config

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Differential D10272

rebase: drop support for rebaseskipobsolete config
Needs RevisionPublic

Authored by martinvonz on Mar 25 2021, 7:35 PM.

Details

Reviewers
marmoute
Group Reviewers
hg-reviewers
Summary

hg rebase has been able to skip obsolete commits since 92409f8dff5d
(rebase: don't rebase obsolete commit whose successor is already
rebased, 2015-09-14). That commit introduced the
experimental.rebaseskipobsolete config and set it to false by
default to start with. Then it has been enabled by default since
a47881680402 (rebase: turn rebaseskipobsolete on by default,
2016-03-09).

It seems to me that all use cases for turning off the config are
covered by hg rebase --keep, hg graft, or hg touch. The use
cases I can think of are:

  1. Create a temporary copy of a set of commits for some experimentation (use hg rebase --keep or hg graft).
  2. Revive a pruned commit (use hg touch, possibly followed by hg rebase if you want to move it elsewhere).

Also, it is a config option after all, which means that it is not
intended for one-off hg rebase commands (then it would have been a
command-line flag). So, let's drop support for this config since it
seems unused. It will make my work on making rewriteutil.precheck()
check for divergence slightly simpler.

Diff Detail

Repository
rHG Mercurial
Branch
default
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Unit
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Event Timeline

martinvonz created this revision.Mar 25 2021, 7:35 PM
pulkit added subscribers: marmoute, pulkit.Apr 8 2021, 1:01 PM

I am +1 on this. I remember there was a discussion on IRC around it but not sure what the end result of that was. @marmoute does having experimental.rebaseskipobsolete serves any purpose?

marmoute requested changes to this revision.Apr 8 2021, 1:15 PM
In D10272#157092, @pulkit wrote:

I am +1 on this. I remember there was a discussion on IRC around it but not sure what the end result of that was. @marmoute does having experimental.rebaseskipobsolete serves any purpose?

Ha yes, thanks for the ping. The short version of my opinion is that experience has shown over and over that having a way to says "select exactly what I requested without tempering with it" are useful. Therefore, we should not drop the flag currently allowing to do that without at least introducing another one.

Neither hg rebase is quite powerfull tool and neither rebase --keep, hg graft or hg touch (?) can really do the same thing. So they don't seem like proper alternative to a simple "do-what-I-said" config/flag.

This revision now requires changes to proceed.Apr 8 2021, 1:15 PM
pulkit added a comment.Jul 20 2021, 4:23 PM
In D10272#157102, @marmoute wrote:
In D10272#157092, @pulkit wrote:

I am +1 on this. I remember there was a discussion on IRC around it but not sure what the end result of that was. @marmoute does having experimental.rebaseskipobsolete serves any purpose?

Ha yes, thanks for the ping. The short version of my opinion is that experience has shown over and over that having a way to says "select exactly what I requested without tempering with it" are useful. Therefore, we should not drop the flag currently allowing to do that without at least introducing another one.
Neither hg rebase is quite powerfull tool and neither rebase --keep, hg graft or hg touch (?) can really do the same thing. So they don't seem like proper alternative to a simple "do-what-I-said" config/flag.

Probably we need a --exact or something similar which also does not skip commits which are already in destination and create empty commits for them too.

Revision Contents
Changeset List

Diff 26600

hgext/rebase.py

) )
return data return data
def _handleskippingobsolete(self): def _handleskippingobsolete(self):
"""Compute structures necessary for skipping obsolete revisions""" """Compute structures necessary for skipping obsolete revisions"""
if self.keepf: if self.keepf:
return return
if not self.ui.configbool(b'experimental', b'rebaseskipobsolete'):
return
obsoleteset = {r for r in self.state if self.repo[r].obsolete()} obsoleteset = {r for r in self.state if self.repo[r].obsolete()}
( (
self.obsolete_with_successor_in_destination, self.obsolete_with_successor_in_destination,
self.obsolete_with_successor_in_rebase_set, self.obsolete_with_successor_in_rebase_set,
) = _compute_obsolete_sets(self.repo, obsoleteset, self.destmap) ) = _compute_obsolete_sets(self.repo, obsoleteset, self.destmap)
skippedset = set(self.obsolete_with_successor_in_destination) skippedset = set(self.obsolete_with_successor_in_destination)
skippedset.update(self.obsolete_with_successor_in_rebase_set) skippedset.update(self.obsolete_with_successor_in_rebase_set)
_checkobsrebase(self.repo, self.ui, obsoleteset, skippedset) _checkobsrebase(self.repo, self.ui, obsoleteset, skippedset)

mercurial/configitems.py

# strange things. For example, shelve import the extensions to reuse some bit # strange things. For example, shelve import the extensions to reuse some bit
# without formally loading it. # without formally loading it.
coreconfigitem( coreconfigitem(
b'commands', b'commands',
b'rebase.requiredest', b'rebase.requiredest',
default=False, default=False,
) )
coreconfigitem( coreconfigitem(
b'experimental',
b'rebaseskipobsolete',
default=True,
)
coreconfigitem(
b'rebase', b'rebase',
b'singletransaction', b'singletransaction',
default=False, default=False,
) )
coreconfigitem( coreconfigitem(
b'rebase', b'rebase',
b'experimental.inmemory', b'experimental.inmemory',
default=False, default=False,
) )

relnotes/next

* In normal repositories, the first parent of a changeset is not null, * In normal repositories, the first parent of a changeset is not null,
unless both parents are null (like the first changeset). Some legacy unless both parents are null (like the first changeset). Some legacy
repositories violate this condition. The revlog code will now repositories violate this condition. The revlog code will now
silentely swap the parents if this condition is tested. This can silentely swap the parents if this condition is tested. This can
change the output of `hg log` when explicitly asking for first or change the output of `hg log` when explicitly asking for first or
second parent. second parent.
* The `experimental.rebaseskipobsolete` config was removed. Obsolete
commits continue to be skipped as they have been for many
years.
== Internal API Changes == == Internal API Changes ==
* `changelog.branchinfo` is deprecated and will be removed after 5.8. * `changelog.branchinfo` is deprecated and will be removed after 5.8.
It is superseded by `changelogrevision.branchinfo`. It is superseded by `changelogrevision.branchinfo`.
* Callbacks for revlog.addgroup and the changelog._nodeduplicatecallback hook * Callbacks for revlog.addgroup and the changelog._nodeduplicatecallback hook
now get a revision number as argument instead of a node. now get a revision number as argument instead of a node.
* revlog.addrevision returns the revision number instead of the node. * revlog.addrevision returns the revision number instead of the node.
* `nodes.nullid` and related constants are being phased out as part of * `nodes.nullid` and related constants are being phased out as part of
the deprecation of SHA1. Repository instances and related classes the deprecation of SHA1. Repository instances and related classes
provide access via `nodeconstants` and in some cases `nullid` attributes. provide access via `nodeconstants` and in some cases `nullid` attributes.

tests/test-rebase-obsolete2.t

Skip obsolete changeset even with multiple hops Skip obsolete changeset even with multiple hops
----------------------------------------------- -----------------------------------------------
setup setup
$ hg init obsskip $ hg init obsskip
$ cd obsskip $ cd obsskip
$ cat << EOF >> .hg/hgrc $ cat << EOF >> .hg/hgrc
> [experimental]
> rebaseskipobsolete = True
> [extensions] > [extensions]
> strip = > strip =
> EOF > EOF
$ echo A > A $ echo A > A
$ hg add A $ hg add A
$ hg commit -m A $ hg commit -m A
$ echo B > B $ echo B > B
$ hg add B $ hg add B

tests/test-rebase-obsolete3.t

| x 3:a82ac2b38757 c | x 3:a82ac2b38757 c
| | | |
o | 2:630d7c95eff7 x o | 2:630d7c95eff7 x
| | | |
| o 1:488e1b7e7341 b | o 1:488e1b7e7341 b
|/ |/
o 0:b173517d0057 a o 0:b173517d0057 a
$ hg strip -r 8:
(Not skipping obsoletes means that divergence is allowed.)
$ hg rebase --config experimental.rebaseskipobsolete=false -r 'c'::'f' -d 'x'
rebasing 3:a82ac2b38757 c "c"
rebasing 4:76be324c128b d "d"
rebasing 7:1143e9adc121 f tip "f"
1 new orphan changesets
2 new content-divergent changesets
$ hg strip -r 0: $ hg strip -r 0:
Similar test on a more complex graph Similar test on a more complex graph
$ hg debugdrawdag <<EOF $ hg debugdrawdag <<EOF
> g > g
> | > |
> f e > f e