view tests/test-rename-merge2.t @ 44363:f7459da77f23

nodemap: introduce an option to use mmap to read the nodemap mapping

The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.

This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).

Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:

Before:

 * do not use the persistent nodemap
 * use the CPython implementation of the index for nodemap
 * use mmapping of the changelog index

After:

 * use the MixedIndex Rust code, with the NodeTree object for nodemap access
   (still in review)
 * use the persistent nodemap data from disk
 * access the persistent nodemap data through mmap
 * use mmapping of the changelog index

The persistent nodemap greatly speed up  most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.

Here are some numbers (in seconds) for the reference copy of mozilla-try:

Revset            Before   After     abs-change speedup

-10000:           0.004622 0.005532   0.000910  ×   0.83
-10:              0.000050 0.000132   0.000082  ×   0.37
tip               0.000052 0.000085   0.000033  ×   0.61
0 + (-10000:)     0.028222 0.005337  -0.022885  ×   5.29
0                 0.023521 0.000084  -0.023437  × 280.01
(-10000:) + 0     0.235539 0.005308  -0.230231  ×  44.37
(-10:) + :9       0.232883 0.000180  -0.232703  ×1293.79
(-10000:) + (:99) 0.238735 0.005358  -0.233377  ×  44.55
:99 + (-10000:)   0.317942 0.005593  -0.312349  ×  56.84
:9 + (-10:)       0.313372 0.000179  -0.313193  ×1750.68
:9                0.316450 0.000143  -0.316307  ×2212.93


On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.

Here are some numbers (in seconds) for the reference copy of mercurial:

Revset            Before   After     abs-change speedup
-10:              0.000065 0.000097   0.000032  × 0.67
tip               0.000063 0.000078   0.000015  × 0.80
0                 0.000561 0.000079  -0.000482  × 7.10
-10000:           0.004609 0.003648  -0.000961  × 1.26
0 + (-10000:)     0.005023 0.003715  -0.001307  × 1.35
(-10:) + :9       0.002187 0.000108  -0.002079  ×20.25
(-10000:) + 0     0.006252 0.003716  -0.002536  × 1.68
(-10000:) + (:99) 0.006367 0.003707  -0.002660  × 1.71
:9 + (-10:)       0.003846 0.000110  -0.003736  ×34.96
:9                0.003854 0.000099  -0.003755  ×38.92
:99 + (-10000:)   0.007644 0.003778  -0.003866  × 2.02

Differential Revision: https://phab.mercurial-scm.org/D7894

  $ mkdir -p t
  $ cd t
  $ cat <<EOF > merge
  > import sys, os
  > f = open(sys.argv[1], "w")
  > f.write("merge %s %s %s" % (sys.argv[1], sys.argv[2], sys.argv[3]))
  > f.close()
  > EOF

perform a test merge with possible renaming
args:
$1 = action in local branch
$2 = action in remote branch
$3 = action in working dir
$4 = expected result

  $ tm()
  > {
  >     hg init t
  >     cd t
  >     echo "[merge]" >> .hg/hgrc
  >     echo "followcopies = 1" >> .hg/hgrc
  > 
  >     # base
  >     echo base > a
  >     echo base > rev # used to force commits
  >     hg add a rev
  >     hg ci -m "base"
  > 
  >     # remote
  >     echo remote > rev
  >     if [ "$2" != "" ] ; then $2 ; fi
  >     hg ci -m "remote"
  > 
  >     # local
  >     hg co -q 0
  >     echo local > rev
  >     if [ "$1" != "" ] ; then $1 ; fi
  >     hg ci -m "local"
  > 
  >     # working dir
  >     echo local > rev
  >     if [ "$3" != "" ] ; then $3 ; fi
  > 
  >     # merge
  >     echo "--------------"
  >     echo "test L:$1 R:$2 W:$3 - $4"
  >     echo "--------------"
  >     hg merge -y --debug --traceback --tool="\"$PYTHON\" ../merge"
  > 
  >     echo "--------------"
  >     hg status -camC -X rev
  > 
  >     hg ci -m "merge"
  > 
  >     echo "--------------"
  >     echo
  > 
  >     cd ..
  >     rm -r t
  > }
  $ up() {
  >     cp rev $1
  >     hg add $1 2> /dev/null
  >     if [ "$2" != "" ] ; then
  >         cp rev $2
  >         hg add $2 2> /dev/null
  >     fi
  > }
  $ um() { up $1; hg mv $1 $2; }
  $ nc() { hg cp $1 $2; } # just copy
  $ nm() { hg mv $1 $2; } # just move
  $ tm "up a  " "nc a b" "      " "1  get local a to b"
  created new head
  --------------
  test L:up a   R:nc a b W:       - 1  get local a to b
  --------------
    unmatched files in other:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: e300d1c794ec+, remote: 4ce40f5aca24
   preserving a for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: remote copied from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging a and b to b
  my b@e300d1c794ec+ other b@4ce40f5aca24 ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@e300d1c794ec+ other rev@4ce40f5aca24 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@e300d1c794ec+ other rev@4ce40f5aca24 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  C a
  --------------
  
  $ tm "nc a b" "up a  " "      " "2  get rem change to a and b"
  created new head
  --------------
  test L:nc a b R:up a   W:       - 2  get rem change to a and b
  --------------
    unmatched files in local:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 86a2aa42fc76+, remote: f4db7e329e71
   preserving b for resolve of b
   preserving rev for resolve of rev
   a: remote is newer -> g
  getting a
   b: local copied/moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b and a to b
  my b@86a2aa42fc76+ other a@f4db7e329e71 ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@86a2aa42fc76+ other rev@f4db7e329e71 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@86a2aa42fc76+ other rev@f4db7e329e71 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M a
  M b
    a
  --------------
  
  $ tm "up a  " "nm a b" "      " "3  get local a change to b, remove a"
  created new head
  --------------
  test L:up a   R:nm a b W:       - 3  get local a change to b, remove a
  --------------
    unmatched files in other:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: e300d1c794ec+, remote: bdb19105162a
   preserving a for resolve of b
   preserving rev for resolve of rev
  removing a
  starting 4 threads for background file closing (?)
   b: remote moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging a and b to b
  my b@e300d1c794ec+ other b@bdb19105162a ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@e300d1c794ec+ other rev@bdb19105162a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@e300d1c794ec+ other rev@bdb19105162a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  --------------
  
  $ tm "nm a b" "up a  " "      " "4  get remote change to b"
  created new head
  --------------
  test L:nm a b R:up a   W:       - 4  get remote change to b
  --------------
    unmatched files in local:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 02963e448370+, remote: f4db7e329e71
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: local copied/moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b and a to b
  my b@02963e448370+ other a@f4db7e329e71 ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@02963e448370+ other rev@f4db7e329e71 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@02963e448370+ other rev@f4db7e329e71 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  --------------
  
  $ tm "      " "nc a b" "      " "5  get b"
  created new head
  --------------
  test L:       R:nc a b W:       - 5  get b
  --------------
    unmatched files in other:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 94b33a1b7f2d+, remote: 4ce40f5aca24
   preserving rev for resolve of rev
   b: remote created -> g
  getting b
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@94b33a1b7f2d+ other rev@4ce40f5aca24 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@94b33a1b7f2d+ other rev@4ce40f5aca24 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  C a
  --------------
  
  $ tm "nc a b" "      " "      " "6  nothing"
  created new head
  --------------
  test L:nc a b R:       W:       - 6  nothing
  --------------
    unmatched files in local:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 86a2aa42fc76+, remote: 97c705ade336
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@86a2aa42fc76+ other rev@97c705ade336 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@86a2aa42fc76+ other rev@97c705ade336 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  C a
  C b
  --------------
  
  $ tm "      " "nm a b" "      " "7  get b"
  created new head
  --------------
  test L:       R:nm a b W:       - 7  get b
  --------------
    unmatched files in other:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 94b33a1b7f2d+, remote: bdb19105162a
   preserving rev for resolve of rev
   a: other deleted -> r
  removing a
   b: remote created -> g
  getting b
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@94b33a1b7f2d+ other rev@bdb19105162a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@94b33a1b7f2d+ other rev@bdb19105162a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 1 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  --------------
  
  $ tm "nm a b" "      " "      " "8  nothing"
  created new head
  --------------
  test L:nm a b R:       W:       - 8  nothing
  --------------
    unmatched files in local:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 02963e448370+, remote: 97c705ade336
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@02963e448370+ other rev@97c705ade336 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@02963e448370+ other rev@97c705ade336 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  C b
  --------------
  
  $ tm "um a b" "um a b" "      " "9  do merge with ancestor in a"
  created new head
  --------------
  test L:um a b R:um a b W:       - 9  do merge with ancestor in a
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 62e7bf090eba+, remote: 49b6d8032493
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: both renamed from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@62e7bf090eba+ other b@49b6d8032493 ancestor a@924404dff337
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@62e7bf090eba+ other rev@49b6d8032493 ancestor rev@924404dff337
   b: both renamed from a -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@62e7bf090eba+ other b@49b6d8032493 ancestor a@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@62e7bf090eba+ other rev@49b6d8032493 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  --------------
  

m "um a c" "um x c" "      " "10 do merge with no ancestor"

  $ tm "nm a b" "nm a c" "      " "11 get c, keep b"
  created new head
  --------------
  test L:nm a b R:nm a c W:       - 11 get c, keep b
  --------------
    unmatched files in local:
     b
    unmatched files in other:
     c
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' !
     on remote side:
      src: 'a' -> dst: 'c' !
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 02963e448370+, remote: fe905ef2c33e
  note: possible conflict - a was renamed multiple times to:
   b
   c
   preserving rev for resolve of rev
   c: remote created -> g
  getting c
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@02963e448370+ other rev@fe905ef2c33e ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@02963e448370+ other rev@fe905ef2c33e ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M c
  C b
  --------------
  
  $ tm "nc a b" "up b  " "      " "12 merge b no ancestor"
  created new head
  --------------
  test L:nc a b R:up b   W:       - 12 merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 86a2aa42fc76+, remote: af30c7647fc7
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: both created -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@86a2aa42fc76+ other b@af30c7647fc7 ancestor b@000000000000
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@86a2aa42fc76+ other rev@af30c7647fc7 ancestor rev@924404dff337
   b: both created -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@86a2aa42fc76+ other b@af30c7647fc7 ancestor b@000000000000
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@86a2aa42fc76+ other rev@af30c7647fc7 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  C a
  --------------
  
  $ tm "up b  " "nm a b" "      " "13 merge b no ancestor"
  created new head
  --------------
  test L:up b   R:nm a b W:       - 13 merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 59318016310c+, remote: bdb19105162a
   preserving b for resolve of b
   preserving rev for resolve of rev
   a: other deleted -> r
  removing a
  starting 4 threads for background file closing (?)
   b: both created -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@59318016310c+ other b@bdb19105162a ancestor b@000000000000
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@59318016310c+ other rev@bdb19105162a ancestor rev@924404dff337
   b: both created -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@59318016310c+ other b@bdb19105162a ancestor b@000000000000
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@59318016310c+ other rev@bdb19105162a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  --------------
  
  $ tm "nc a b" "up a b" "      " "14 merge b no ancestor"
  created new head
  --------------
  test L:nc a b R:up a b W:       - 14 merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 86a2aa42fc76+, remote: 8dbce441892a
   preserving b for resolve of b
   preserving rev for resolve of rev
   a: remote is newer -> g
  getting a
   b: both renamed from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@86a2aa42fc76+ other b@8dbce441892a ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@86a2aa42fc76+ other rev@8dbce441892a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@86a2aa42fc76+ other rev@8dbce441892a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M a
  M b
  --------------
  
  $ tm "up b  " "nm a b" "      " "15 merge b no ancestor, remove a"
  created new head
  --------------
  test L:up b   R:nm a b W:       - 15 merge b no ancestor, remove a
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' 
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 59318016310c+, remote: bdb19105162a
   preserving b for resolve of b
   preserving rev for resolve of rev
   a: other deleted -> r
  removing a
  starting 4 threads for background file closing (?)
   b: both created -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@59318016310c+ other b@bdb19105162a ancestor b@000000000000
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@59318016310c+ other rev@bdb19105162a ancestor rev@924404dff337
   b: both created -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@59318016310c+ other b@bdb19105162a ancestor b@000000000000
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@59318016310c+ other rev@bdb19105162a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  --------------
  
  $ tm "nc a b" "up a b" "      " "16 get a, merge b no ancestor"
  created new head
  --------------
  test L:nc a b R:up a b W:       - 16 get a, merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 86a2aa42fc76+, remote: 8dbce441892a
   preserving b for resolve of b
   preserving rev for resolve of rev
   a: remote is newer -> g
  getting a
   b: both renamed from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@86a2aa42fc76+ other b@8dbce441892a ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@86a2aa42fc76+ other rev@8dbce441892a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@86a2aa42fc76+ other rev@8dbce441892a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M a
  M b
  --------------
  
  $ tm "up a b" "nc a b" "      " "17 keep a, merge b no ancestor"
  created new head
  --------------
  test L:up a b R:nc a b W:       - 17 keep a, merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 0b76e65c8289+, remote: 4ce40f5aca24
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: both renamed from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@0b76e65c8289+ other b@4ce40f5aca24 ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@0b76e65c8289+ other rev@4ce40f5aca24 ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@0b76e65c8289+ other rev@4ce40f5aca24 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  C a
  --------------
  
  $ tm "nm a b" "up a b" "      " "18 merge b no ancestor"
  created new head
  --------------
  test L:nm a b R:up a b W:       - 18 merge b no ancestor
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 02963e448370+, remote: 8dbce441892a
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: both renamed from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@02963e448370+ other b@8dbce441892a ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@02963e448370+ other rev@8dbce441892a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@02963e448370+ other rev@8dbce441892a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  --------------
  
  $ tm "up a b" "nm a b" "      " "19 merge b no ancestor, prompt remove a"
  created new head
  --------------
  test L:up a b R:nm a b W:       - 19 merge b no ancestor, prompt remove a
  --------------
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 0b76e65c8289+, remote: bdb19105162a
   preserving b for resolve of b
   preserving rev for resolve of rev
   b: both renamed from a -> m (premerge)
  starting 4 threads for background file closing (?)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b
  my b@0b76e65c8289+ other b@bdb19105162a ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@0b76e65c8289+ other rev@bdb19105162a ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@0b76e65c8289+ other rev@bdb19105162a ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
  C a
  --------------
  
  $ tm "up a  " "um a b" "      " "20 merge a and b to b, remove a"
  created new head
  --------------
  test L:up a   R:um a b W:       - 20 merge a and b to b, remove a
  --------------
    unmatched files in other:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on remote side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: e300d1c794ec+, remote: 49b6d8032493
   preserving a for resolve of b
   preserving rev for resolve of rev
  removing a
  starting 4 threads for background file closing (?)
   b: remote moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging a and b to b
  my b@e300d1c794ec+ other b@49b6d8032493 ancestor a@924404dff337
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@e300d1c794ec+ other rev@49b6d8032493 ancestor rev@924404dff337
   b: remote moved from a -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@e300d1c794ec+ other b@49b6d8032493 ancestor a@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@e300d1c794ec+ other rev@49b6d8032493 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  --------------
  
  $ tm "um a b" "up a  " "      " "21 merge a and b to b"
  created new head
  --------------
  test L:um a b R:up a   W:       - 21 merge a and b to b
  --------------
    unmatched files in local:
     b
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 62e7bf090eba+, remote: f4db7e329e71
   preserving b for resolve of b
   preserving rev for resolve of rev
  starting 4 threads for background file closing (?)
   b: local copied/moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b and a to b
  my b@62e7bf090eba+ other a@f4db7e329e71 ancestor a@924404dff337
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@62e7bf090eba+ other rev@f4db7e329e71 ancestor rev@924404dff337
   b: local copied/moved from a -> m (merge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  my b@62e7bf090eba+ other a@f4db7e329e71 ancestor a@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/b* * * (glob)
  merge tool returned: 0
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@62e7bf090eba+ other rev@f4db7e329e71 ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  --------------
  

m "nm a b" "um x a" "      " "22 get a, keep b"

  $ tm "nm a b" "up a c" "      " "23 get c, keep b"
  created new head
  --------------
  test L:nm a b R:up a c W:       - 23 get c, keep b
  --------------
    unmatched files in local:
     b
    unmatched files in other:
     c
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: 'a' -> dst: 'b' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: 924404dff337, local: 02963e448370+, remote: 2b958612230f
   preserving b for resolve of b
   preserving rev for resolve of rev
   c: remote created -> g
  getting c
   b: local copied/moved from a -> m (premerge)
  picked tool '* ../merge' for b (binary False symlink False changedelete False) (glob)
  merging b and a to b
  my b@02963e448370+ other a@2b958612230f ancestor a@924404dff337
   premerge successful
   rev: versions differ -> m (premerge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  merging rev
  my rev@02963e448370+ other rev@2b958612230f ancestor rev@924404dff337
   rev: versions differ -> m (merge)
  picked tool '* ../merge' for rev (binary False symlink False changedelete False) (glob)
  my rev@02963e448370+ other rev@2b958612230f ancestor rev@924404dff337
  launching merge tool: * ../merge *$TESTTMP/t/t/rev* * * (glob)
  merge tool returned: 0
  1 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  --------------
  M b
    a
  M c
  --------------
  

  $ cd ..


Systematic and terse testing of merge merges and ancestor calculation:

Expected result:

\  a  m1  m2  dst
0  -   f   f   f   "versions differ"
1  f   g   g   g   "versions differ"
2  f   f   f   f   "versions differ"
3  f   f   g  f+g  "remote copied to " + f
4  f   f   g   g   "remote moved to " + f
5  f   g   f  f+g  "local copied to " + f2
6  f   g   f   g   "local moved to " + f2
7  -  (f)  f   f   "remote differs from untracked local"
8  f  (f)  f   f   "remote differs from untracked local"

  $ hg init ancestortest
  $ cd ancestortest
  $ for x in 1 2 3 4 5 6 8; do mkdir $x; echo a > $x/f; done
  $ hg ci -Aqm "a"
  $ mkdir 0
  $ touch 0/f
  $ hg mv 1/f 1/g
  $ hg cp 5/f 5/g
  $ hg mv 6/f 6/g
  $ hg rm 8/f
  $ for x in */*; do echo m1 > $x; done
  $ hg ci -Aqm "m1"
  $ hg up -qr0
  $ mkdir 0 7
  $ touch 0/f 7/f
  $ hg mv 1/f 1/g
  $ hg cp 3/f 3/g
  $ hg mv 4/f 4/g
  $ for x in */*; do echo m2 > $x; done
  $ hg ci -Aqm "m2"
  $ hg up -qr1
  $ mkdir 7 8
  $ echo m > 7/f
  $ echo m > 8/f
  $ hg merge -f --tool internal:dump -v --debug -r2 | sed '/^resolving manifests/,$d' 2> /dev/null
    unmatched files in local:
     5/g
     6/g
    unmatched files in other:
     3/g
     4/g
     7/f
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     on local side:
      src: '1/f' -> dst: '1/g' *
      src: '5/f' -> dst: '5/g' *
      src: '6/f' -> dst: '6/g' *
     on remote side:
      src: '1/f' -> dst: '1/g' *
      src: '3/f' -> dst: '3/g' *
      src: '4/f' -> dst: '4/g' *
    checking for directory renames
  $ hg mani
  0/f
  1/g
  2/f
  3/f
  4/f
  5/f
  5/g
  6/g
  $ for f in */*; do echo $f:; cat $f; done
  0/f:
  m1
  0/f.base:
  0/f.local:
  m1
  0/f.orig:
  m1
  0/f.other:
  m2
  1/g:
  m1
  1/g.base:
  a
  1/g.local:
  m1
  1/g.orig:
  m1
  1/g.other:
  m2
  2/f:
  m1
  2/f.base:
  a
  2/f.local:
  m1
  2/f.orig:
  m1
  2/f.other:
  m2
  3/f:
  m1
  3/f.base:
  a
  3/f.local:
  m1
  3/f.orig:
  m1
  3/f.other:
  m2
  3/g:
  m1
  3/g.base:
  a
  3/g.local:
  m1
  3/g.orig:
  m1
  3/g.other:
  m2
  4/g:
  m1
  4/g.base:
  a
  4/g.local:
  m1
  4/g.orig:
  m1
  4/g.other:
  m2
  5/f:
  m1
  5/f.base:
  a
  5/f.local:
  m1
  5/f.orig:
  m1
  5/f.other:
  m2
  5/g:
  m1
  5/g.base:
  a
  5/g.local:
  m1
  5/g.orig:
  m1
  5/g.other:
  m2
  6/g:
  m1
  6/g.base:
  a
  6/g.local:
  m1
  6/g.orig:
  m1
  6/g.other:
  m2
  7/f:
  m
  7/f.base:
  7/f.local:
  m
  7/f.orig:
  m
  7/f.other:
  m2
  8/f:
  m2
  $ cd ..