comparison tests/test-convert-filemap.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.

17102:d9a046ae4d8e

  $ glog -R branchpruning-hg2
  o  1 "closedefault" files:
  |
  o  0 "addb" files: b
  

17103:5146de7bce96

  $ glog -R branchpruning-hg2
  o  1 "closedefault" files:
  |
  o  0 "addb" files: b
  

test merge parents/empty merges pruning

  $ glog()
  > {
  >     hg glog --template '{rev}:{node|short}@{branch} "{desc}" files: {files}\n' "$@"
  > }

test anonymous branch pruning

  $ hg init anonymousbranch
  $ cd anonymousbranch
  $ echo a > a
  $ echo b > b
  $ hg ci -Am add
  adding a
  adding b
  $ echo a >> a
  $ hg ci -m changea
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo b >> b
  $ hg ci -m changeb
  created new head
  $ hg up 1
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m merge
  $ cd ..

  $ cat > filemap <<EOF
  > include a
  > EOF
  $ hg convert --filemap filemap anonymousbranch anonymousbranch-hg
  initializing destination anonymousbranch-hg repository
  scanning source...
  sorting...
  converting...
  3 add
  2 changea
  1 changeb
  0 merge
  $ glog -R anonymousbranch
  @    3:c71d5201a498@default "merge" files:
  |\
  | o  2:607eb44b17f9@default "changeb" files: b
  | |
  o |  1:1f60ea617824@default "changea" files: a
  |/
  o  0:0146e6129113@default "add" files: a b
  
  $ glog -R anonymousbranch-hg
  o  1:cda818e7219b@default "changea" files: a
  |
  o  0:c334dc3be0da@default "add" files: a
  
  $ cat anonymousbranch-hg/.hg/shamap
  0146e6129113dba9ac90207cfdf2d7ed35257ae5 c334dc3be0daa2a4e9ce4d2e2bdcba40c09d4916
  1f60ea61782421edf8d051ff4fcb61b330f26a4a cda818e7219b5f7f3fb9f49780054ed6a1905ec3
  607eb44b17f9348cd5cbd26e16af87ba77b0b037 c334dc3be0daa2a4e9ce4d2e2bdcba40c09d4916
  c71d5201a498b2658d105a6bf69d7a0df2649aea cda818e7219b5f7f3fb9f49780054ed6a1905ec3

  $ cat > filemap <<EOF
  > include b
  > EOF
  $ hg convert --filemap filemap anonymousbranch anonymousbranch-hg2
  initializing destination anonymousbranch-hg2 repository
  scanning source...
  sorting...
  converting...
  3 add
  2 changea
  1 changeb
  0 merge
  $ glog -R anonymousbranch
  @    3:c71d5201a498@default "merge" files:
  |\
  | o  2:607eb44b17f9@default "changeb" files: b
  | |
  o |  1:1f60ea617824@default "changea" files: a
  |/
  o  0:0146e6129113@default "add" files: a b
  
  $ glog -R anonymousbranch-hg2
  o  1:62dd350b0df6@default "changeb" files: b
  |
  o  0:4b9ced861657@default "add" files: b
  
  $ cat anonymousbranch-hg2/.hg/shamap
  0146e6129113dba9ac90207cfdf2d7ed35257ae5 4b9ced86165703791653059a1db6ed864630a523
  1f60ea61782421edf8d051ff4fcb61b330f26a4a 4b9ced86165703791653059a1db6ed864630a523
  607eb44b17f9348cd5cbd26e16af87ba77b0b037 62dd350b0df695f7d2c82a02e0499b16fd790f22
  c71d5201a498b2658d105a6bf69d7a0df2649aea 62dd350b0df695f7d2c82a02e0499b16fd790f22

test named branch pruning

  $ hg init namedbranch
  $ cd namedbranch
  $ echo a > a
  $ echo b > b
  $ hg ci -Am add
  adding a
  adding b
  $ echo a >> a
  $ hg ci -m changea
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg branch foo
  marked working directory as branch foo
  (branches are permanent and global, did you want a bookmark?)
  $ echo b >> b
  $ hg ci -m changeb
  $ hg up default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge foo
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m merge
  $ cd ..

  $ cat > filemap <<EOF
  > include a
  > EOF
  $ hg convert --filemap filemap namedbranch namedbranch-hg
  initializing destination namedbranch-hg repository
  scanning source...
  sorting...
  converting...
  3 add
  2 changea
  1 changeb
  0 merge
  $ glog -R namedbranch
  @    3:73899bcbe45c@default "merge" files:
  |\
  | o  2:8097982d19fc@foo "changeb" files: b
  | |
  o |  1:1f60ea617824@default "changea" files: a
  |/
  o  0:0146e6129113@default "add" files: a b
  
  $ glog -R namedbranch-hg
  o  1:cda818e7219b@default "changea" files: a
  |
  o  0:c334dc3be0da@default "add" files: a
  

  $ cd namedbranch
  $ hg --config extensions.mq= strip tip
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/namedbranch/.hg/strip-backup/73899bcbe45c-backup.hg
  $ hg up foo
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m merge
  $ cd ..

  $ hg convert --filemap filemap namedbranch namedbranch-hg2
  initializing destination namedbranch-hg2 repository
  scanning source...
  sorting...
  converting...
  3 add
  2 changea
  1 changeb
  0 merge
  $ glog -R namedbranch
  @    3:e1959de76e1b@foo "merge" files:
  |\
  | o  2:8097982d19fc@foo "changeb" files: b
  | |
  o |  1:1f60ea617824@default "changea" files: a
  |/
  o  0:0146e6129113@default "add" files: a b
  
  $ glog -R namedbranch-hg2
  o    2:dcf314454667@foo "merge" files:
  |\
  | o  1:cda818e7219b@default "changea" files: a
  |/
  o  0:c334dc3be0da@default "add" files: a