view tests/test-rebase-rename.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=
  > 
  > [alias]
  > tlog  = log  --template "{rev}: '{desc}' {branches}\n"
  > tglog = tlog --graph
  > EOF


  $ hg init a
  $ cd a

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

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

  $ hg up -q -C 0

  $ hg mv a a-renamed

  $ hg ci -m 'rename A'
  created new head

  $ hg tglog
  @  2: 'rename A'
  |
  | o  1: 'B'
  |/
  o  0: 'A'
  

Rename is tracked:

  $ hg tlog -p --git -r tip
  2: 'rename A' 
  diff --git a/a b/a-renamed
  rename from a
  rename to a-renamed
  
Rebase the revision containing the rename:

  $ hg rebase -s 2 -d 1
  saved backup bundle to $TESTTMP/a/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  2: 'rename A'
  |
  o  1: 'B'
  |
  o  0: 'A'
  

Rename is not lost:

  $ hg tlog -p --git -r tip
  2: 'rename A' 
  diff --git a/a b/a-renamed
  rename from a
  rename to a-renamed
  
  $ cd ..


  $ hg init b
  $ cd b

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

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

  $ hg up -q -C 0

  $ hg cp a a-copied
  $ hg ci -m 'copy A'
  created new head

  $ hg tglog
  @  2: 'copy A'
  |
  | o  1: 'B'
  |/
  o  0: 'A'
  
Copy is tracked:

  $ hg tlog -p --git -r tip
  2: 'copy A' 
  diff --git a/a b/a-copied
  copy from a
  copy to a-copied
  
Rebase the revision containing the copy:

  $ hg rebase -s 2 -d 1
  saved backup bundle to $TESTTMP/b/.hg/strip-backup/*-backup.hg (glob)

  $ hg tglog
  @  2: 'copy A'
  |
  o  1: 'B'
  |
  o  0: 'A'
  
Copy is not lost:

  $ hg tlog -p --git -r tip
  2: 'copy A' 
  diff --git a/a b/a-copied
  copy from a
  copy to a-copied
  
  $ cd ..


Test rebase across repeating renames:

  $ hg init repo

  $ cd repo

  $ echo testing > file1.txt
  $ hg add file1.txt
  $ hg ci -m "Adding file1"

  $ hg rename file1.txt file2.txt
  $ hg ci -m "Rename file1 to file2"

  $ echo Unrelated change > unrelated.txt
  $ hg add unrelated.txt
  $ hg ci -m "Unrelated change"

  $ hg rename file2.txt file1.txt
  $ hg ci -m "Rename file2 back to file1"

  $ hg update -r -2
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ echo Another unrelated change >> unrelated.txt
  $ hg ci -m "Another unrelated change"
  created new head

  $ hg tglog
  @  4: 'Another unrelated change'
  |
  | o  3: 'Rename file2 back to file1'
  |/
  o  2: 'Unrelated change'
  |
  o  1: 'Rename file1 to file2'
  |
  o  0: 'Adding file1'
  

  $ hg rebase -s 4 -d 3
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-backup.hg (glob)

  $ hg diff --stat -c .
   unrelated.txt |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)

  $ cd ..