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.
This test file aims at test topological iteration and the various configuration it can has.
$ cat >> $HGRCPATH << EOF
> [ui]
> logtemplate={rev}\n
> EOF
On this simple example, all topological branch are displayed in turn until we
can finally display 0. this implies skipping from 8 to 3 and coming back to 7
later.
$ hg init test01
$ cd test01
$ hg unbundle $TESTDIR/bundles/remote.hg
adding changesets
adding manifests
adding file changes
added 9 changesets with 7 changes to 4 files (+1 heads)
new changesets bfaf4b5cbf01:916f1afdef90 (9 drafts)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg log -G
o 8
|
| o 7
| |
| o 6
| |
| o 5
| |
| o 4
| |
o | 3
| |
o | 2
| |
o | 1
|/
o 0
(display all nodes)
$ hg log -G -r 'sort(all(), topo)'
o 8
|
o 3
|
o 2
|
o 1
|
| o 7
| |
| o 6
| |
| o 5
| |
| o 4
|/
o 0
(display nodes filtered by log options)
$ hg log -G -r 'sort(all(), topo)' -k '.3'
o 8
|
o 3
|
~
o 7
|
o 6
|
~
(revset skipping nodes)
$ hg log -G --rev 'sort(not (2+6), topo)'
o 8
|
o 3
:
o 1
|
| o 7
| :
| o 5
| |
| o 4
|/
o 0
(begin) from the other branch
$ hg log -G -r 'sort(all(), topo, topo.firstbranch=5)'
o 7
|
o 6
|
o 5
|
o 4
|
| o 8
| |
| o 3
| |
| o 2
| |
| o 1
|/
o 0
Topological sort can be turned on via config
$ cat >> $HGRCPATH << EOF
> [experimental]
> log.topo=true
> EOF
$ hg log -G
o 8
|
o 3
|
o 2
|
o 1
|
| o 7
| |
| o 6
| |
| o 5
| |
| o 4
|/
o 0
Does not affect non-graph log
$ hg log -T '{rev}\n'
8
7
6
5
4
3
2
1
0