$ hg init

  $ echo "[merge]" >> .hg/hgrc

  $ echo "followcopies = 1" >> .hg/hgrc

  $ echo foo > a

  $ echo foo > a2

  $ hg add a a2

  $ hg ci -m "start"

  $ hg mv a b

  $ hg mv a2 b2

  $ hg ci -m "rename"

  $ hg co 0

  2 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ echo blahblah > a

  $ echo blahblah > a2

  $ hg mv a2 c2

  $ hg ci -m "modify"

  created new head

  $ hg merge -y --debug

    searching for copies back to rev 1

    unmatched files in local:

     c2

    unmatched files in other:

     b

     b2

    all copies found (* = to merge, ! = divergent):

     c2 -> a2 !

     b -> a *

     b2 -> a2 !

    checking for directory renames

   a2: divergent renames -> dr

  resolving manifests

   overwrite None partial False

   ancestor af1939970a1c local 044f8520aeeb+ remote 85c198ef2f6c

   a: remote moved to b -> m

   b2: remote created -> g

  preserving a for resolve of b

  removing a

  updating: a 1/3 files (33.33%)

  picked tool 'internal:merge' for b (binary False symlink False)

  merging a and b to b

  my b@044f8520aeeb+ other b@85c198ef2f6c ancestor a@af1939970a1c

   premerge successful

  updating: a2 2/3 files (66.67%)

  warning: detected divergent renames of a2 to:

   c2

   b2

  updating: b2 3/3 files (100.00%)

  getting b2

  1 files updated, 1 files merged, 0 files removed, 0 files unresolved

  (branch merge, don't forget to commit)

  $ hg status -AC

  M b

    a

  M b2

  R a

  C c2

  $ cat b

  blahblah

  $ hg ci -m "merge"

  $ hg debugindex .hg/store/data/b.i

     rev    offset  length   base linkrev nodeid       p1           p2

       0         0      67      0       1 57eacc201a7f 000000000000 000000000000

       1        67      72      1       3 4727ba907962 000000000000 57eacc201a7f

  $ hg debugrename b

  b renamed from a:dd03b83622e78778b403775d0d074b9ac7387a66