view tests/test-rebase-interruptions.t @ 17103:5146de7bce96

convert: keep branch switching merges with ancestors (issue3340)

When running convert with a filemap, merge parents which are ancestors
of other parents are ignored. This is hardly a problem when parents
belong to the same branch, but the result could be confusing when named
branches are involved. With:

  -o-a1-a2-a3...     <- A
    \           \
     b1-b2-b3...-m-  <- B

If all b* revisions are discarded, it is useful to preserve 'm' even if
it is empty after filtering to record the branch switch.

This patch makes filemap preserve "ancestor parents" if there is no
"non-ancestor parent" on the same branch than the merge revision.

Remarks:
- I am not completely convinced by the reasons given above and those
  detailed by Matt in this thread:

http://selenic.com/pipermail/mercurial-devel/2012-May/040627.html

  The properties we try to preserve are not clearly defined. That said,
  I know this patch already helped someone on IRC and the tests output
  look reasonable.

- This is a new version of the original "convert: filemap must preserve
  fast-forward merges" patch. It has exactly the same output for 2
  parents merges, the additional complexity is here to handle more than
  two parents.

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > graphlog=
  > rebase=
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog = log -G --template "{rev}: '{desc}' {branches}\n"
  > tglogp = log -G --template "{rev}:{phase} '{desc}' {branches}\n"
  > EOF


  $ hg init a
  $ cd a

  $ echo A > A
  $ hg ci -Am A
  adding A

  $ echo B > B
  $ hg ci -Am B
  adding 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 ci -Am E
  adding E

  $ cd ..


Changes during an interruption - continue:

  $ hg clone -q -u . a a1
  $ cd a1

  $ hg tglog
  @  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  merging A
  warning: conflicts during merge.
  merging A incomplete! (edit conflicts, then use 'hg resolve --mark')
  abort: unresolved conflicts (see hg resolve, then hg rebase --continue)
  [255]

Force a commit on C during the interruption:

  $ hg up -q -C 2

  $ echo 'Extra' > Extra
  $ hg add Extra
  $ hg ci -m 'Extra'

Force this commit onto secret phase

  $ hg phase --force --secret 6

  $ hg tglogp
  @  6:secret 'Extra'
  |
  | o  5:draft 'B'
  | |
  | o  4:draft 'E'
  | |
  | o  3:draft 'D'
  | |
  o |  2:draft 'C'
  | |
  o |  1:draft 'B'
  |/
  o  0:draft 'A'
  
Resume the rebasing:

  $ hg rebase --continue
  merging A
  warning: conflicts during merge.
  merging A incomplete! (edit conflicts, then use 'hg resolve --mark')
  abort: unresolved conflicts (see hg resolve, then hg rebase --continue)
  [255]

Solve the conflict and go on:

  $ echo 'conflict solved' > A
  $ rm A.orig
  $ hg resolve -m A

  $ hg rebase --continue
  warning: new changesets detected on source branch, not stripping

  $ hg tglogp
  @  7:draft 'C'
  |
  | o  6:secret 'Extra'
  | |
  o |  5:draft 'B'
  | |
  o |  4:draft 'E'
  | |
  o |  3:draft 'D'
  | |
  | o  2:draft 'C'
  | |
  | o  1:draft 'B'
  |/
  o  0:draft 'A'
  
  $ cd ..


Changes during an interruption - abort:

  $ hg clone -q -u . a a2
  $ cd a2

  $ hg tglog
  @  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  merging A
  warning: conflicts during merge.
  merging A incomplete! (edit conflicts, then use 'hg resolve --mark')
  abort: unresolved conflicts (see hg resolve, then hg rebase --continue)
  [255]

Force a commit on B' during the interruption:

  $ hg up -q -C 5

  $ echo 'Extra' > Extra
  $ hg add Extra
  $ hg ci -m 'Extra'

  $ hg tglog
  @  6: 'Extra'
  |
  o  5: 'B'
  |
  o  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Abort the rebasing:

  $ hg rebase --abort
  warning: new changesets detected on target branch, can't abort
  [255]

  $ hg tglog
  @  6: 'Extra'
  |
  o  5: 'B'
  |
  o  4: 'E'
  |
  o  3: 'D'
  |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..

Changes during an interruption - abort (again):

  $ hg clone -q -u . a a3
  $ cd a3

  $ hg tglogp
  @  4:draft 'E'
  |
  o  3:draft 'D'
  |
  | o  2:draft 'C'
  | |
  | o  1:draft 'B'
  |/
  o  0:draft 'A'
  
Rebasing B onto E:

  $ hg rebase -s 1 -d 4
  merging A
  warning: conflicts during merge.
  merging A incomplete! (edit conflicts, then use 'hg resolve --mark')
  abort: unresolved conflicts (see hg resolve, then hg rebase --continue)
  [255]

Change phase on B and B'

  $ hg up -q -C 5
  $ hg phase --public 1
  $ hg phase --public 5
  $ hg phase --secret -f 2

  $ hg tglogp
  @  5:public 'B'
  |
  o  4:public 'E'
  |
  o  3:public 'D'
  |
  | o  2:secret 'C'
  | |
  | o  1:public 'B'
  |/
  o  0:public 'A'
  
Abort the rebasing:

  $ hg rebase --abort
  abort: can't abort rebase due to immutable changesets 45396c49d53b
  (see hg help phases for details)
  [255]

  $ hg tglogp
  @  5:public 'B'
  |
  o  4:public 'E'
  |
  o  3:public 'D'
  |
  | o  2:secret 'C'
  | |
  | o  1:public 'B'
  |/
  o  0:public 'A'
  
  $ cd ..