absorb: preserve changesets which were already empty
Most commands in Mercurial (commit, rebase, absorb itself) don’t create empty
changesets or drop them if they become empty. If there’s a changeset that’s
empty, it must be a deliberate choice of the user. At least it shouldn’t be
absorb’s responsibility to prune them. The fact that changesets that became
empty during absorb are pruned, is unaffected by this.
This case was found while writing patches which make it possible to configure
absorb and rebase to not drop empty changesets. Even without having such config
set, I think it’s valuable to preserve changesets which were already empty.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> rebase=
>
> [phases]
> publish=False
>
> [alias]
> tglog = log -G --template "{rev}:{phase} '{desc}' {branches}\n"
> EOF
$ hg init a
$ cd a
$ echo A > A
$ hg add A
$ hg ci -m A
$ echo 'B' > B
$ hg add B
$ hg ci -m B
$ echo C >> A
$ hg ci -m C
$ hg up -q -C 0
$ echo D >> A
$ hg ci -m D
created new head
$ echo E > E
$ hg add E
$ hg ci -m E
$ hg up -q -C 0
$ hg branch 'notdefault'
marked working directory as branch notdefault
(branches are permanent and global, did you want a bookmark?)
$ echo F >> A
$ hg ci -m F
$ cd ..
Rebasing B onto E - check keep: and phases
$ hg clone -q -u . a a1
$ cd a1
$ hg phase --force --secret 2
$ hg tglog
@ 5:draft 'F' notdefault
|
| o 4:draft 'E'
| |
| o 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ hg rebase -s 1 -d 4 --keep
rebasing 1:27547f69f254 "B"
rebasing 2:965c486023db "C"
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
unresolved conflicts (see hg resolve, then hg rebase --continue)
[1]
Solve the conflict and go on:
$ echo 'conflict solved' > A
$ rm A.orig
$ hg resolve -m A
(no more unresolved files)
continue: hg rebase --continue
$ hg rebase --continue
already rebased 1:27547f69f254 "B" as 45396c49d53b
rebasing 2:965c486023db "C"
$ hg tglog
o 7:secret 'C'
|
o 6:draft 'B'
|
| @ 5:draft 'F' notdefault
| |
o | 4:draft 'E'
| |
o | 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ cd ..
Rebase F onto E - check keepbranches:
$ hg clone -q -u . a a2
$ cd a2
$ hg phase --force --secret 2
$ hg tglog
@ 5:draft 'F' notdefault
|
| o 4:draft 'E'
| |
| o 3:draft 'D'
|/
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ hg rebase -s 5 -d 4 --keepbranches
rebasing 5:01e6ebbd8272 "F" (tip)
merging A
warning: conflicts while merging A! (edit, then use 'hg resolve --mark')
unresolved conflicts (see hg resolve, then hg rebase --continue)
[1]
Solve the conflict and go on:
$ echo 'conflict solved' > A
$ rm A.orig
$ hg resolve -m A
(no more unresolved files)
continue: hg rebase --continue
$ hg rebase --continue
rebasing 5:01e6ebbd8272 "F" (tip)
saved backup bundle to $TESTTMP/a2/.hg/strip-backup/01e6ebbd8272-6fd3a015-rebase.hg
$ hg tglog
@ 5:draft 'F' notdefault
|
o 4:draft 'E'
|
o 3:draft 'D'
|
| o 2:secret 'C'
| |
| o 1:draft 'B'
|/
o 0:draft 'A'
$ cd ..