view tests/test-rebase-named-branches.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"
  > EOF

  $ hg init a
  $ cd a
  $ 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
  $ cd ..

  $ hg clone -q -u . a a1

  $ cd a1

  $ hg update 3
  3 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ hg branch dev-one
  marked working directory as branch dev-one
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -m 'dev-one named branch'

  $ hg update 7
  2 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ hg branch dev-two
  marked working directory as branch dev-two
  (branches are permanent and global, did you want a bookmark?)

  $ echo x > x

  $ hg add x

  $ hg ci -m 'dev-two named branch'

  $ hg tglog
  @  9: 'dev-two named branch' dev-two
  |
  | o  8: 'dev-one named branch' dev-one
  | |
  o |  7: 'H'
  | |
  +---o  6: 'G'
  | | |
  o | |  5: 'F'
  | | |
  +---o  4: 'E'
  | |
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  

Branch name containing a dash (issue3181)

  $ hg rebase -b dev-two -d dev-one --keepbranches
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  9: 'dev-two named branch' dev-two
  |
  o  8: 'H'
  |
  | o  7: 'G'
  |/|
  o |  6: 'F'
  | |
  o |  5: 'dev-one named branch' dev-one
  | |
  | o  4: 'E'
  | |
  o |  3: 'D'
  | |
  o |  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  
  $ hg rebase -s dev-one -d 0 --keepbranches
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  8: 'dev-two named branch' dev-two
  |
  o  7: 'H'
  |
  | o  6: 'G'
  |/|
  o |  5: 'F'
  | |
  | o  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ hg update 3
  3 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ hg branch dev-one
  marked working directory as branch dev-one
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -m 'dev-one named branch'

  $ hg tglog
  @  9: 'dev-one named branch' dev-one
  |
  | o  8: 'dev-two named branch' dev-two
  | |
  | o  7: 'H'
  | |
  | | o  6: 'G'
  | |/|
  | o |  5: 'F'
  | | |
  | | o  4: 'E'
  | |/
  o |  3: 'D'
  | |
  o |  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  
  $ hg rebase -b 'max(branch("dev-two"))' -d dev-one --keepbranches
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  9: 'dev-two named branch' dev-two
  |
  o  8: 'H'
  |
  | o  7: 'G'
  |/|
  o |  6: 'F'
  | |
  o |  5: 'dev-one named branch' dev-one
  | |
  | o  4: 'E'
  | |
  o |  3: 'D'
  | |
  o |  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  
  $ hg rebase -s 'max(branch("dev-one"))' -d 0 --keepbranches
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  8: 'dev-two named branch' dev-two
  |
  o  7: 'H'
  |
  | o  6: 'G'
  |/|
  o |  5: 'F'
  | |
  | o  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  

Rebasing descendant onto ancestor across different named branches

  $ hg rebase -s 1 -d 8 --keepbranches
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  8: 'D'
  |
  o  7: 'C'
  |
  o  6: 'B'
  |
  o  5: 'dev-two named branch' dev-two
  |
  o  4: 'H'
  |
  | o  3: 'G'
  |/|
  o |  2: 'F'
  | |
  | o  1: 'E'
  |/
  o  0: 'A'
  
  $ hg rebase -s 4 -d 5
  abort: source is ancestor of destination
  [255]

  $ hg rebase -s 5 -d 4
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  8: 'D'
  |
  o  7: 'C'
  |
  o  6: 'B'
  |
  o  5: 'dev-two named branch'
  |
  o  4: 'H'
  |
  | o  3: 'G'
  |/|
  o |  2: 'F'
  | |
  | o  1: 'E'
  |/
  o  0: 'A'
  
  $ cd ..