rebase: do not invent successor to skipped changeset
When rebase results in an empty a changeset it is "skipped" and no related
changeset is created at all. When we added obsolescence support to rebase (in
fc2a6114f0a0) it seemed a good idea to use its parent successor as the
successors for such dropped changesets. (see old version of the altered test).
This option was chosen because it seems a good way to hint about were the
dropped changeset "intended" to be. Such hint would have been used by automatic
evolution mechanism to rebase potential unstable children.
However, field testing of this version are not conclusive. It very often leads
to the creation of (totally unfounded) evolution divergence. This changeset
changes this behavior and mark skipped changesets as pruned (obsolete without
successors). This prevents the issue and seems semantically better probably a
win for obsolescence reading tool.
See example bellow for details:
User Babar has five changesets of interest:
- O, its current base of development.
- U, the new upstream
- A and C, some development changesets
- B another development changeset independent from A
O - A - B - C
\
U
Babar decides that B is more critical than the A and C and rebase it first
$ hg rebase --rev B --dest U
B is now obsolete (in lower case bellow). Rebase result, B', is its
successors.(note, C is unstable)
O - A - b - C
\
U - B'
Babar is now done with B', and want to rebase the rest of its history:
$ hg rebase --source A --dest B'
hg rebase process A, B and C. B is skipped as all its changes are already contained
in B'.
O - U - B' - A' - C'
Babar have the expected result graph wise, obsolescence marker are as follow:
B -> B' (from first rebase)
A -> A' (from second rebase)
C -> C' (from second rebase)
B -> ?? (from second rebase)
Before this changeset, the last marker is `B -> A'`. This cause two issues:
- This is semantically wrong. B have nothing to do with A'
- B has now two successors sets: (B',) and (A',). We detect a divergent
rewriting. The B' and A' are reported as "divergent" to Babar, confusion
ensues. In addition such divergent situation (divergent changeset are children
to each other) is tricky to solve.
With this changeset the last marker is `B -> ΓΈ`:
- This is semantically better.
- B has a single successors set (B',)
This scenario is added to the tests suite.
==========================
Test rebase with obsolete
==========================
Enable obsolete
$ cat > ${TESTTMP}/obs.py << EOF
> import mercurial.obsolete
> mercurial.obsolete._enabled = True
> EOF
$ cat >> $HGRCPATH << EOF
> [ui]
> logtemplate= {rev}:{node|short} {desc|firstline}
> [phases]
> publish=False
> [extensions]'
> rebase=
>
> obs=${TESTTMP}/obs.py
> EOF
Setup rebase canonical repo
$ hg init base
$ cd base
$ hg unbundle "$TESTDIR/bundles/rebase.hg"
adding changesets
adding manifests
adding file changes
added 8 changesets with 7 changes to 7 files (+2 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg up tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg log -G
@ 7:02de42196ebe H
|
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
| o 3:32af7686d403 D
| |
| o 2:5fddd98957c8 C
| |
| o 1:42ccdea3bb16 B
|/
o 0:cd010b8cd998 A
$ cd ..
simple rebase
---------------------------------
$ hg clone base simple
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd simple
$ hg up 32af7686d403
3 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg rebase -d eea13746799a
$ hg log -G
@ 10:8eeb3c33ad33 D
|
o 9:2327fea05063 C
|
o 8:e4e5be0395b2 B
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ hg log --hidden -G
@ 10:8eeb3c33ad33 D
|
o 9:2327fea05063 C
|
o 8:e4e5be0395b2 B
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
| x 3:32af7686d403 D
| |
| x 2:5fddd98957c8 C
| |
| x 1:42ccdea3bb16 B
|/
o 0:cd010b8cd998 A
$ hg debugobsolete
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 e4e5be0395b2cbd471ed22a26b1b6a1a0658a794 0 {'date': '*', 'user': 'test'} (glob)
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 2327fea05063f39961b14cb69435a9898dc9a245 0 {'date': '*', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a 8eeb3c33ad33d452c89e5dcf611c347f978fb42b 0 {'date': '*', 'user': 'test'} (glob)
$ cd ..
empty changeset
---------------------------------
$ hg clone base empty
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd empty
$ hg up eea13746799a
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
We make a copy of both the first changeset in the rebased and some other in the
set.
$ hg graft 42ccdea3bb16 32af7686d403
grafting revision 1
grafting revision 3
$ hg rebase -s 42ccdea3bb16 -d .
$ hg log -G
@ 10:5ae4c968c6ac C
|
o 9:08483444fef9 D
|
o 8:8877864f1edb B
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ hg log --hidden -G
@ 10:5ae4c968c6ac C
|
o 9:08483444fef9 D
|
o 8:8877864f1edb B
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
| x 3:32af7686d403 D
| |
| x 2:5fddd98957c8 C
| |
| x 1:42ccdea3bb16 B
|/
o 0:cd010b8cd998 A
$ hg debugobsolete
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {'date': '*', 'user': 'test'} (glob)
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 {'date': '*', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a 0 {'date': '*', 'user': 'test'} (glob)
More complex case were part of the rebase set were already rebased
$ hg rebase --rev 'desc(D)' --dest 'desc(H)'
$ hg debugobsolete
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {'date': '*', 'user': 'test'} (glob)
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 {'date': '*', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a 0 {'date': '*', 'user': 'test'} (glob)
08483444fef91d6224f6655ee586a65d263ad34c cbc07f26687521cecfc9a141bf5ecfc0fd2b8531 0 {'date': '* *', 'user': 'test'} (glob)
$ hg log -G
@ 11:cbc07f266875 D
|
| o 10:5ae4c968c6ac C
| |
| x 9:08483444fef9 D
| |
| o 8:8877864f1edb B
| |
o | 7:02de42196ebe H
| |
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ hg rebase --source 'desc(B)' --dest 'tip'
$ hg debugobsolete
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 0 {'date': '* *', 'user': 'test'} (glob)
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 5ae4c968c6aca831df823664e706c9d4aa34473d 0 {'date': '* *', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a 0 {'date': '* *', 'user': 'test'} (glob)
08483444fef91d6224f6655ee586a65d263ad34c cbc07f26687521cecfc9a141bf5ecfc0fd2b8531 0 {'date': '* *', 'user': 'test'} (glob)
8877864f1edb05d0e07dc4ba77b67a80a7b86672 b1861c79d66ec3aa1b607ac3c9fb819e38b12238 0 {'date': '* *', 'user': 'test'} (glob)
08483444fef91d6224f6655ee586a65d263ad34c 0 {'date': '* *', 'user': 'test'} (glob)
5ae4c968c6aca831df823664e706c9d4aa34473d dd4be135457a404ce5541de427ae1d98a28f4acd 0 {'date': '* *', 'user': 'test'} (glob)
$ hg log --rev 'divergent()'
$ hg log -G
@ 13:dd4be135457a C
|
o 12:b1861c79d66e B
|
o 11:cbc07f266875 D
|
o 7:02de42196ebe H
|
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ cd ..
collapse rebase
---------------------------------
$ hg clone base collapse
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd collapse
$ hg rebase -s 42ccdea3bb16 -d eea13746799a --collapse
$ hg log -G
@ 8:4dc2197e807b Collapsed revision
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ hg log --hidden -G
@ 8:4dc2197e807b Collapsed revision
|
| o 7:02de42196ebe H
| |
o | 6:eea13746799a G
|\|
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
| x 3:32af7686d403 D
| |
| x 2:5fddd98957c8 C
| |
| x 1:42ccdea3bb16 B
|/
o 0:cd010b8cd998 A
$ hg id --debug
4dc2197e807bae9817f09905b50ab288be2dbbcf tip
$ hg debugobsolete
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 4dc2197e807bae9817f09905b50ab288be2dbbcf 0 {'date': '*', 'user': 'test'} (glob)
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b 4dc2197e807bae9817f09905b50ab288be2dbbcf 0 {'date': '*', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a 4dc2197e807bae9817f09905b50ab288be2dbbcf 0 {'date': '*', 'user': 'test'} (glob)
$ cd ..
Rebase set has hidden descendants
---------------------------------
We rebase a changeset which has a hidden changeset. The hidden changeset must
not be rebased.
$ hg clone base hidden
updating to branch default
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd hidden
$ hg rebase -s 5fddd98957c8 -d eea13746799a
$ hg rebase -s 42ccdea3bb16 -d 02de42196ebe
$ hg log -G
@ 10:7c6027df6a99 B
|
| o 9:cf44d2f5a9f4 D
| |
| o 8:e273c5e7d2d2 C
| |
o | 7:02de42196ebe H
| |
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ hg log --hidden -G
@ 10:7c6027df6a99 B
|
| o 9:cf44d2f5a9f4 D
| |
| o 8:e273c5e7d2d2 C
| |
o | 7:02de42196ebe H
| |
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
| x 3:32af7686d403 D
| |
| x 2:5fddd98957c8 C
| |
| x 1:42ccdea3bb16 B
|/
o 0:cd010b8cd998 A
$ hg debugobsolete
5fddd98957c8a54a4d436dfe1da9d87f21a1b97b e273c5e7d2d29df783dce9f9eaa3ac4adc69c15d 0 {'date': '*', 'user': 'test'} (glob)
32af7686d403cf45b5d95f2d70cebea587ac806a cf44d2f5a9f4297a62be94cbdd3dff7c7dc54258 0 {'date': '*', 'user': 'test'} (glob)
42ccdea3bb16d28e1848c95fe2e44c000f3f21b1 7c6027df6a99d93f461868e5433f63bde20b6dfb 0 {'date': '*', 'user': 'test'} (glob)
Test that rewriting leaving instability behind is allowed
---------------------------------------------------------------------
$ hg log -r 'children(8)'
9:cf44d2f5a9f4 D (no-eol)
$ hg rebase -r 8
$ hg log -G
@ 11:0d8f238b634c C
|
o 10:7c6027df6a99 B
|
| o 9:cf44d2f5a9f4 D
| |
| x 8:e273c5e7d2d2 C
| |
o | 7:02de42196ebe H
| |
| o 6:eea13746799a G
|/|
o | 5:24b6387c8c8c F
| |
| o 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
Test multiple root handling
------------------------------------
$ hg rebase --dest 4 --rev '7+11+9'
$ hg log -G
@ 14:00891d85fcfc C
|
| o 13:102b4c1d889b D
|/
| o 12:bfe264faf697 H
|/
| o 10:7c6027df6a99 B
| |
| x 7:02de42196ebe H
| |
+---o 6:eea13746799a G
| |/
| o 5:24b6387c8c8c F
| |
o | 4:9520eea781bc E
|/
o 0:cd010b8cd998 A
$ cd ..