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.
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init a
$ cd a
$ echo 'base' > base
$ hg ci -Ambase -d '1 0'
adding base
$ hg qnew -d '1 0' pa
$ hg qnew -d '1 0' pb
$ hg qnew -d '1 0' pc
$ hg qdel
abort: qdelete requires at least one revision or patch name
[255]
$ hg qdel pc
abort: cannot delete applied patch pc
[255]
$ hg qpop
popping pc
now at: pb
Delete the same patch twice in one command (issue2427)
$ hg qdel pc pc
$ hg qseries
pa
pb
$ ls .hg/patches
pa
pb
series
status
$ hg qpop
popping pb
now at: pa
$ hg qdel -k 1
$ ls .hg/patches
pa
pb
series
status
$ hg qdel -r pa
patch pa finalized without changeset message
$ hg qapplied
$ hg log --template '{rev} {desc}\n'
1 [mq]: pa
0 base
$ hg qnew pd
$ hg qnew pe
$ hg qnew pf
$ hg qdel -r pe
abort: cannot delete revision 3 above applied patches
[255]
$ hg qdel -r qbase:pe
patch pd finalized without changeset message
patch pe finalized without changeset message
$ hg qapplied
pf
$ hg log --template '{rev} {desc}\n'
4 [mq]: pf
3 [mq]: pe
2 [mq]: pd
1 [mq]: pa
0 base
$ cd ..
$ hg init b
$ cd b
$ echo 'base' > base
$ hg ci -Ambase -d '1 0'
adding base
$ hg qfinish
abort: no revisions specified
[255]
$ hg qfinish -a
no patches applied
$ hg qnew -d '1 0' pa
$ hg qnew -d '1 0' pb
$ hg qnew pc # XXX fails to apply by /usr/bin/patch if we put a date
$ hg qfinish 0
abort: revision 0 is not managed
[255]
$ hg qfinish pb
abort: cannot delete revision 2 above applied patches
[255]
$ hg qpop
popping pc
now at: pb
$ hg qfinish -a pc
abort: unknown revision 'pc'!
[255]
$ hg qpush
applying pc
patch pc is empty
now at: pc
$ hg qfinish qbase:pb
patch pa finalized without changeset message
patch pb finalized without changeset message
$ hg qapplied
pc
$ hg log --template '{rev} {desc}\n'
3 imported patch pc
2 [mq]: pb
1 [mq]: pa
0 base
$ hg qfinish -a pc
patch pc finalized without changeset message
$ hg qapplied
$ hg log --template '{rev} {desc}\n'
3 imported patch pc
2 [mq]: pb
1 [mq]: pa
0 base
$ ls .hg/patches
series
status
qdel -k X && hg qimp -e X used to trigger spurious output with versioned queues
$ hg init --mq
$ hg qimport -r 3
$ hg qpop
popping imported_patch_pc
patch queue now empty
$ hg qdel -k imported_patch_pc
$ hg qimp -e imported_patch_pc
adding imported_patch_pc to series file
$ hg qfinish -a
no patches applied
resilience to inconsistency: qfinish -a with applied patches not in series
$ hg qser
imported_patch_pc
$ hg qapplied
$ hg qpush
applying imported_patch_pc
patch imported_patch_pc is empty
now at: imported_patch_pc
$ echo next >> base
$ hg qrefresh -d '1 0'
$ echo > .hg/patches/series # remove 3.diff from series to confuse mq
$ hg qfinish -a
revision 47dfa8501675 refers to unknown patches: imported_patch_pc
more complex state 'both known and unknown patches
$ echo hip >> base
$ hg qnew -f -d '1 0' -m 4 4.diff
$ echo hop >> base
$ hg qnew -f -d '1 0' -m 5 5.diff
$ echo > .hg/patches/series # remove 4.diff and 5.diff from series to confuse mq
$ echo hup >> base
$ hg qnew -f -d '1 0' -m 6 6.diff
$ echo pup > base
$ hg qfinish -a
warning: uncommitted changes in the working directory
revision 2b1c98802260 refers to unknown patches: 5.diff
revision 33a6861311c0 refers to unknown patches: 4.diff
$ cd ..