view tests/test-rename-dir-merge.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.

  $ hg init t
  $ cd t

  $ mkdir a
  $ echo foo > a/a
  $ echo bar > a/b
  $ hg ci -Am "0"
  adding a/a
  adding a/b

  $ hg co -C 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg mv a b
  moving a/a to b/a (glob)
  moving a/b to b/b (glob)
  $ hg ci -m "1 mv a/ b/"

  $ hg co -C 0
  2 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo baz > a/c
  $ echo quux > a/d
  $ hg add a/c
  $ hg ci -m "2 add a/c"
  created new head

  $ hg merge --debug 1
    searching for copies back to rev 1
    unmatched files in local:
     a/c
    unmatched files in other:
     b/a
     b/b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     b/a -> a/a 
     b/b -> a/b 
    checking for directory renames
    dir a/ -> b/
    file a/c -> b/c
  resolving manifests
   overwrite: False, partial: False
   ancestor: f9b20c0d4c51, local: ce36d17b18fb+, remote: 397f8b00a740
   a/c: remote renamed directory to b/c -> d
   a/b: other deleted -> r
   a/a: other deleted -> r
   b/a: remote created -> g
   b/b: remote created -> g
  updating: a/a 1/5 files (20.00%)
  removing a/a
  updating: a/b 2/5 files (40.00%)
  removing a/b
  updating: a/c 3/5 files (60.00%)
  moving a/c to b/c
  updating: b/a 4/5 files (80.00%)
  getting b/a
  updating: b/b 5/5 files (100.00%)
  getting b/b
  3 files updated, 0 files merged, 2 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ echo a/* b/*
  a/d b/a b/b b/c
  $ hg st -C
  M b/a
  M b/b
  A b/c
    a/c
  R a/a
  R a/b
  R a/c
  ? a/d
  $ hg ci -m "3 merge 2+1"
  $ hg debugrename b/c
  b/c renamed from a/c:354ae8da6e890359ef49ade27b68bbc361f3ca88 (glob)

  $ hg co -C 1
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge --debug 2
    searching for copies back to rev 1
    unmatched files in local:
     b/a
     b/b
    unmatched files in other:
     a/c
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     b/a -> a/a 
     b/b -> a/b 
    checking for directory renames
    dir a/ -> b/
    file a/c -> b/c
  resolving manifests
   overwrite: False, partial: False
   ancestor: f9b20c0d4c51, local: 397f8b00a740+, remote: ce36d17b18fb
   None: local renamed directory to b/c -> d
  updating:None 1/1 files (100.00%)
  getting a/c to b/c
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ echo a/* b/*
  a/d b/a b/b b/c
  $ hg st -C
  A b/c
    a/c
  ? a/d
  $ hg ci -m "4 merge 1+2"
  created new head
  $ hg debugrename b/c
  b/c renamed from a/c:354ae8da6e890359ef49ade27b68bbc361f3ca88 (glob)


Second scenario with two repos:

  $ cd ..
  $ hg init r1
  $ cd r1
  $ mkdir a
  $ echo foo > a/f
  $ hg add a
  adding a/f (glob)
  $ hg ci -m "a/f == foo"
  $ cd ..

  $ hg clone r1 r2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd r2
  $ hg mv a b
  moving a/f to b/f (glob)
  $ echo foo1 > b/f
  $ hg ci -m" a -> b, b/f == foo1"
  $ cd ..

  $ cd r1
  $ mkdir a/aa
  $ echo bar > a/aa/g
  $ hg add a/aa
  adding a/aa/g (glob)
  $ hg ci -m "a/aa/g"
  $ hg pull ../r2
  pulling from ../r2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)

  $ hg merge
  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg st -C
  M b/f
  A b/aa/g
    a/aa/g
  R a/aa/g
  R a/f

  $ cd ..