view tests/test-resolve.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.

test that a commit clears the merge state.

  $ hg init repo
  $ cd repo

  $ echo foo > file
  $ hg commit -Am 'add file'
  adding file

  $ echo bar >> file
  $ hg commit -Am 'append bar'


create a second head

  $ hg up -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo baz >> file
  $ hg commit -Am 'append baz'
  created new head

failing merge

  $ hg merge --tool=internal:fail
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]

  $ echo resolved > file
  $ hg resolve -m file
  $ hg commit -m 'resolved'

resolve -l, should be empty

  $ hg resolve -l

test crashed merge with empty mergestate

  $ mkdir .hg/merge
  $ touch .hg/merge/state

resolve -l, should be empty

  $ hg resolve -l

  $ cd ..