view tests/test-evolve-public-content-divergent-corner-cases.t @ 4728:ef8907df73fc stable

touch: fix the inconsistent behavior of divergence catching logic (issue6107)

When touching a node, the way we check if it can lead to divergence
is we look at the successors sets of the rev being touched. And if
there is successor revs exists (excluding the case when that successor
set is (A,) for rev A) that means there will be divergence and we warn
the user.
This works fine but there is still a case (which is not covered by looking
at successor sets) which can lead to divergence.

That case is: when there is already a revision exists which is divergent
to the revision being touched. And performing the touch would revive
that "dead" divergence. (Dead because one of the revision is obsolete which
is the one we are touching)

And to see if there is any rev which is divergent to a particular rev
we already have a function which we can use here
i.e. `evolvecmd.divergentsets(repo, ctx_being_touched)`

Changes in test file demonstrate the fixed behaviour.

===============================================================
Tests the resolution of public content divergence: corner cases
===============================================================

This file intend to cover cases that are specific enough to not fit in the
other cases.

Setup
=====
  $ cat >> $HGRCPATH <<EOF
  > [alias]
  > glog = log -GT "{rev}:{node|short} {desc|firstline}\n {phase} {instabilities}\n\n"
  > [phases]
  > publish = False
  > [extensions]
  > rebase =
  > EOF
  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH

Testing when divergence is not created by actual diff change, but because of rebasing:
--------------------------------------------------------------------------------------

Prepare the repo:

  $ hg init rebasediv
  $ cd rebasediv
  $ for ch in a b c; do
  >   echo $ch > $ch;
  >   hg ci -Am "added "$ch;
  > done;
  adding a
  adding b
  adding c

  $ hg glog
  @  2:155349b645be added c
  |   draft
  |
  o  1:5f6d8a4bf34a added b
  |   draft
  |
  o  0:9092f1db7931 added a
      draft
  

On server side: a new cset is added based on rev 1 and rev 2 is rebased on newly added cset:

  $ hg up .^ -q
  $ echo d > d
  $ hg ci -Am "added d"
  adding d
  created new head

  $ hg rebase -r 2 -d .
  rebasing 2:155349b645be "added c"

  $ hg glog
  o  4:c0d7ee6604ea added c
  |   draft
  |
  @  3:c9241b0f2d5b added d
  |   draft
  |
  o  1:5f6d8a4bf34a added b
  |   draft
  |
  o  0:9092f1db7931 added a
      draft
  

On user side: user has not pulled yet and amended the rev 2 which created the divergence after pull:
  $ hg up 2 --hidden -q
  updated to hidden changeset 155349b645be
  (hidden revision '155349b645be' was rewritten as: c0d7ee6604ea)
  working directory parent is obsolete! (155349b645be)

  $ echo cc >> c
  $ hg ci --amend -m "updated c"
  2 new content-divergent changesets

Lets change the phase to --public of branch which is pulled from server:
  $ hg phase --public -r 4
  $ hg glog -p
  @  5:f5f9b4fc8b77 updated c
  |   draft content-divergent
  |
  |  diff -r 5f6d8a4bf34a -r f5f9b4fc8b77 c
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,2 @@
  |  +c
  |  +cc
  |
  | o  4:c0d7ee6604ea added c
  | |   public
  | |
  | |  diff -r c9241b0f2d5b -r c0d7ee6604ea c
  | |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  | |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  | |  @@ -0,0 +1,1 @@
  | |  +c
  | |
  | o  3:c9241b0f2d5b added d
  |/    public
  |
  |    diff -r 5f6d8a4bf34a -r c9241b0f2d5b d
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +d
  |
  o  1:5f6d8a4bf34a added b
  |   public
  |
  |  diff -r 9092f1db7931 -r 5f6d8a4bf34a b
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +b
  |
  o  0:9092f1db7931 added a
      public
  
     diff -r 000000000000 -r 9092f1db7931 a
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/a	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +a
  

Evolve:
  $ hg evolve --content-divergent
  merge:[4] added c
  with: [5] updated c
  base: [2] added c
  rebasing "other" content-divergent changeset f5f9b4fc8b77 on c9241b0f2d5b
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  committed as 3b336cbee992
  working directory is now at 3b336cbee992

  $ hg glog -p
  @  8:3b336cbee992 phase-divergent update to c0d7ee6604ea:
  |   draft
  |
  |  diff -r c0d7ee6604ea -r 3b336cbee992 c
  |  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -1,1 +1,2 @@
  |   c
  |  +cc
  |
  o  4:c0d7ee6604ea added c
  |   public
  |
  |  diff -r c9241b0f2d5b -r c0d7ee6604ea c
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c
  |
  o  3:c9241b0f2d5b added d
  |   public
  |
  |  diff -r 5f6d8a4bf34a -r c9241b0f2d5b d
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +d
  |
  o  1:5f6d8a4bf34a added b
  |   public
  |
  |  diff -r 9092f1db7931 -r 5f6d8a4bf34a b
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +b
  |
  o  0:9092f1db7931 added a
      public
  
     diff -r 000000000000 -r 9092f1db7931 a
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/a	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +a
  
Check that we don't have any unstable cset now:
  $ hg evolve -l
  $ cd ..

Different parent, simple conflict on relocate, deleted file on actual merge
---------------------------------------------------------------------------

Changeset "added c e" is also removing 'd'. This should conflict with the update
to 'd' in the successors of 'adding d' when solving the content divergence.

  $ hg init pubdiv-parent-deleted-file
  $ cd pubdiv-parent-deleted-file
  $ for ch in a b c d; do
  >   echo $ch > $ch;
  >   hg ci -Aqm "added "$ch;
  > done;

  $ hg up 'desc("added b")'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo cfoo > c
  $ echo e > e
  $ hg add c e
  $ hg ci -m "added c e"
  created new head

  $ hg up 'desc("re:added c$")'
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo dd > d
  $ hg add d
  $ hg ci -m "added d"
  created new head

  $ hg glog --patch --rev 'sort(all(), "topo")'
  @  5:93cd84bbdaca added d
  |   draft
  |
  |  diff -r 155349b645be -r 93cd84bbdaca d
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +dd
  |
  | o  3:9150fe93bec6 added d
  |/    draft
  |
  |    diff -r 155349b645be -r 9150fe93bec6 d
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +d
  |
  o  2:155349b645be added c
  |   draft
  |
  |  diff -r 5f6d8a4bf34a -r 155349b645be c
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c
  |
  | o  4:e568fd1029bb added c e
  |/    draft
  |
  |    diff -r 5f6d8a4bf34a -r e568fd1029bb c
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +cfoo
  |    diff -r 5f6d8a4bf34a -r e568fd1029bb e
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/e	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +e
  |
  o  1:5f6d8a4bf34a added b
  |   draft
  |
  |  diff -r 9092f1db7931 -r 5f6d8a4bf34a b
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +b
  |
  o  0:9092f1db7931 added a
      draft
  
     diff -r 000000000000 -r 9092f1db7931 a
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/a	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +a
  
  $ hg prune 'min(desc("added d"))' -s 'max(desc("added d"))'
  1 changesets pruned
  $ hg prune 'min(desc("added d"))' -s 'desc("added c e")' --hidden
  1 changesets pruned
  2 new content-divergent changesets

Change phase to public for one head:
  $ hg phase --public -r 'max(desc("added d"))'

  $ hg glog
  @  5:93cd84bbdaca added d
  |   public
  |
  | *  4:e568fd1029bb added c e
  | |   draft content-divergent
  | |
  o |  2:155349b645be added c
  |/    public
  |
  o  1:5f6d8a4bf34a added b
  |   public
  |
  o  0:9092f1db7931 added a
      public
  

  $ hg glog --patch --rev 'sort(all(), "topo")' --hidden
  @  5:93cd84bbdaca added d
  |   public
  |
  |  diff -r 155349b645be -r 93cd84bbdaca d
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +dd
  |
  | x  3:9150fe93bec6 added d
  |/    draft
  |
  |    diff -r 155349b645be -r 9150fe93bec6 d
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +d
  |
  o  2:155349b645be added c
  |   public
  |
  |  diff -r 5f6d8a4bf34a -r 155349b645be c
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c
  |
  | *  4:e568fd1029bb added c e
  |/    draft content-divergent
  |
  |    diff -r 5f6d8a4bf34a -r e568fd1029bb c
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +cfoo
  |    diff -r 5f6d8a4bf34a -r e568fd1029bb e
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/e	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +e
  |
  o  1:5f6d8a4bf34a added b
  |   public
  |
  |  diff -r 9092f1db7931 -r 5f6d8a4bf34a b
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +b
  |
  o  0:9092f1db7931 added a
      public
  
     diff -r 000000000000 -r 9092f1db7931 a
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/a	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +a
  

  $ hg obslog --all --rev tip --patch
  @  93cd84bbdaca (5) added d
  |
  | *  e568fd1029bb (4) added c e
  |/
  x  9150fe93bec6 (3) added d
       rewritten(content) as 93cd84bbdaca using prune by test (Thu Jan 01 00:00:00 1970 +0000)
         diff -r 9150fe93bec6 -r 93cd84bbdaca d
         --- a/d	Thu Jan 01 00:00:00 1970 +0000
         +++ b/d	Thu Jan 01 00:00:00 1970 +0000
         @@ -1,1 +1,1 @@
         -d
         +dd
  
       rewritten(description, parent, content) as e568fd1029bb using prune by test (Thu Jan 01 00:00:00 1970 +0000)
         (No patch available, changesets rebased)
  

  $ hg evolve --content-divergent --any --update
  merge:[5] added d
  with: [4] added c e
  base: [3] added d
  rebasing "other" content-divergent changeset e568fd1029bb on 155349b645be
  merging c
  warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
  fix conflicts and see `hg help evolve.interrupted`
  [1]

  $ hg diff
  diff -r 155349b645be c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,5 @@
  +<<<<<<< destination: 155349b645be - test: added c
   c
  +=======
  +cfoo
  +>>>>>>> evolving:    e568fd1029bb - test: added c e
  diff -r 155349b645be e
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/e	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +e

  $ echo c > c
  $ hg res -m
  (no more unresolved files)
  continue: hg evolve --continue

  $ hg evolve --continue
  evolving 4:e568fd1029bb "added c e"
  file 'd' was deleted in other but was modified in local.
  What do you want to do?
  use (c)hanged version, (d)elete, or leave (u)nresolved? u
  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
  fix conflicts and see `hg help evolve.interrupted`
  [1]

  $ hg sum
  parent: 5:93cd84bbdaca 
   added d
  parent: 6:2af3359250d3 tip (content-divergent)
   added c e
  branch: default
  commit: 1 modified, 1 unknown, 1 unresolved (merge)
  update: (current)
  phases: 1 draft
  content-divergent: 1 changesets
  evolve: (evolve --continue)

  $ echo resolved > d
  $ hg resolve -m d
  (no more unresolved files)
  continue: hg evolve --continue

  $ hg evolve --continue
  committed as bc1f4610744c
  working directory is now at bc1f4610744c

  $ hg export
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID bc1f4610744c6aa0e851d3876a61bfff6243b31c
  # Parent  93cd84bbdacaeb8f881c29a609dbdd30c38cbc57
  phase-divergent update to 93cd84bbdaca:
  
  added c e
  
  diff -r 93cd84bbdaca -r bc1f4610744c d
  --- a/d	Thu Jan 01 00:00:00 1970 +0000
  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -dd
  +resolved
  diff -r 93cd84bbdaca -r bc1f4610744c e
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/e	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +e

  $ hg evolve -l
  $ cd ..

Test a pratical "rebase" case
=============================

Initial setup

  $ hg init rebase-divergence
  $ cd rebase-divergence
  $ echo root >> root
  $ hg add root
  $ hg commit -m root
  $ for x in c_A c_B c_C c_D; do
  >     echo $x >> $x
  >     hg add $x
  >     hg commit -m $x
  > done

  $ hg up 'desc("c_A")'
  0 files updated, 0 files merged, 3 files removed, 0 files unresolved

  $ for x in c_E c_F; do
  >     echo $x >> $x
  >     hg add $x
  >     hg commit -m $x
  > done
  created new head

(creating divergence locally for simplicity)

  $ node=`hg log --rev 'desc("c_E")' -T '{node}'`
  $ hg rebase -s $node -d 'desc("c_B")'
  rebasing 5:4ab2719bbab9 "c_E"
  rebasing 6:77ccbf8d837e "c_F" (tip)
  $ hg phase --public tip
  $ hg rebase --hidden -s $node -d 'desc("c_C")' --config experimental.evolution.allowdivergence=yes
  rebasing 5:4ab2719bbab9 "c_E"
  rebasing 6:77ccbf8d837e "c_F"
  2 new content-divergent changesets

  $ hg sum
  parent: 8:a52ac76b45f5 
   c_F
  branch: default
  commit: (clean)
  update: 4 new changesets, 3 branch heads (merge)
  phases: 4 draft
  content-divergent: 2 changesets
  $ hg evolve --list
  b4a584aea4bd: c_E
    content-divergent: c7d2d47c7240 (public) (precursor 4ab2719bbab9)
  
  8ae8db670b4a: c_F
    content-divergent: a52ac76b45f5 (public) (precursor 77ccbf8d837e)
  
  $ hg log -G --patch
  *  changeset:   10:8ae8db670b4a
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  instability: content-divergent
  |  summary:     c_F
  |
  |  diff -r b4a584aea4bd -r 8ae8db670b4a c_F
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_F	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_F
  |
  *  changeset:   9:b4a584aea4bd
  |  parent:      3:abb77b893f28
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  instability: content-divergent
  |  summary:     c_E
  |
  |  diff -r abb77b893f28 -r b4a584aea4bd c_E
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_E	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_E
  |
  | @  changeset:   8:a52ac76b45f5
  | |  user:        test
  | |  date:        Thu Jan 01 00:00:00 1970 +0000
  | |  summary:     c_F
  | |
  | |  diff -r c7d2d47c7240 -r a52ac76b45f5 c_F
  | |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  | |  +++ b/c_F	Thu Jan 01 00:00:00 1970 +0000
  | |  @@ -0,0 +1,1 @@
  | |  +c_F
  | |
  | o  changeset:   7:c7d2d47c7240
  | |  parent:      2:eb1b4e1205b8
  | |  user:        test
  | |  date:        Thu Jan 01 00:00:00 1970 +0000
  | |  summary:     c_E
  | |
  | |  diff -r eb1b4e1205b8 -r c7d2d47c7240 c_E
  | |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  | |  +++ b/c_E	Thu Jan 01 00:00:00 1970 +0000
  | |  @@ -0,0 +1,1 @@
  | |  +c_E
  | |
  +---o  changeset:   4:dbb960d6c97c
  | |    user:        test
  | |    date:        Thu Jan 01 00:00:00 1970 +0000
  | |    summary:     c_D
  | |
  | |    diff -r abb77b893f28 -r dbb960d6c97c c_D
  | |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  | |    +++ b/c_D	Thu Jan 01 00:00:00 1970 +0000
  | |    @@ -0,0 +1,1 @@
  | |    +c_D
  | |
  o |  changeset:   3:abb77b893f28
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     c_C
  |
  |    diff -r eb1b4e1205b8 -r abb77b893f28 c_C
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/c_C	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +c_C
  |
  o  changeset:   2:eb1b4e1205b8
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_B
  |
  |  diff -r e31751786014 -r eb1b4e1205b8 c_B
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_B	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_B
  |
  o  changeset:   1:e31751786014
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_A
  |
  |  diff -r 1e4be0697311 -r e31751786014 c_A
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_A	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_A
  |
  o  changeset:   0:1e4be0697311
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     root
  
     diff -r 000000000000 -r 1e4be0697311 root
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/root	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +root
  

Run automatic evolution

  $ hg evolve --content-divergent --rev 'not public() and desc("c_E")::'
  merge:[7] c_E
  with: [9] c_E
  base: [5] c_E
  rebasing "other" content-divergent changeset b4a584aea4bd on eb1b4e1205b8
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  content divergence resolution between c7d2d47c7240 (public) and 0773642cfa95 has same content as c7d2d47c7240, discarding 0773642cfa95
  merge:[8] c_F
  with: [10] c_F
  base: [6] c_F
  rebasing "other" content-divergent changeset 8ae8db670b4a on c7d2d47c7240
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  content divergence resolution between a52ac76b45f5 (public) and 6a87ed4aa317 has same content as a52ac76b45f5, discarding 6a87ed4aa317
  $ hg sum
  parent: 8:a52ac76b45f5 tip
   c_F
  branch: default
  commit: (clean)
  update: 2 new changesets, 2 branch heads (merge)
  phases: 2 draft

  $ hg evolve --list

  $ hg log -G --patch
  @  changeset:   8:a52ac76b45f5
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_F
  |
  |  diff -r c7d2d47c7240 -r a52ac76b45f5 c_F
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_F	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_F
  |
  o  changeset:   7:c7d2d47c7240
  |  parent:      2:eb1b4e1205b8
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_E
  |
  |  diff -r eb1b4e1205b8 -r c7d2d47c7240 c_E
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_E	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_E
  |
  | o  changeset:   4:dbb960d6c97c
  | |  user:        test
  | |  date:        Thu Jan 01 00:00:00 1970 +0000
  | |  summary:     c_D
  | |
  | |  diff -r abb77b893f28 -r dbb960d6c97c c_D
  | |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  | |  +++ b/c_D	Thu Jan 01 00:00:00 1970 +0000
  | |  @@ -0,0 +1,1 @@
  | |  +c_D
  | |
  | o  changeset:   3:abb77b893f28
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     c_C
  |
  |    diff -r eb1b4e1205b8 -r abb77b893f28 c_C
  |    --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |    +++ b/c_C	Thu Jan 01 00:00:00 1970 +0000
  |    @@ -0,0 +1,1 @@
  |    +c_C
  |
  o  changeset:   2:eb1b4e1205b8
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_B
  |
  |  diff -r e31751786014 -r eb1b4e1205b8 c_B
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_B	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_B
  |
  o  changeset:   1:e31751786014
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c_A
  |
  |  diff -r 1e4be0697311 -r e31751786014 c_A
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/c_A	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,1 @@
  |  +c_A
  |
  o  changeset:   0:1e4be0697311
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     root
  
     diff -r 000000000000 -r 1e4be0697311 root
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/root	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +root
  
  $ hg export tip
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID a52ac76b45f523a039fc4a938d79874f4bdb1a85
  # Parent  c7d2d47c7240562be5cbd1a24080dd0396178709
  c_F
  
  diff -r c7d2d47c7240 -r a52ac76b45f5 c_F
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c_F	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +c_F

  $ hg obslog --rev a52ac76b45f5
  @    a52ac76b45f5 (8) c_F
  |\
  x |  6a87ed4aa317 (12) c_F
  | |    rewritten as a52ac76b45f5 using evolve by test (Thu Jan 01 00:00:00 1970 +0000)
  | |
  x |  8ae8db670b4a (10) c_F
  |/     rewritten(parent) as 6a87ed4aa317 using evolve by test (Thu Jan 01 00:00:00 1970 +0000)
  |
  x  77ccbf8d837e (6) c_F
       rewritten(parent) as 8ae8db670b4a using rebase by test (Thu Jan 01 00:00:00 1970 +0000)
       rewritten(parent) as a52ac76b45f5 using rebase by test (Thu Jan 01 00:00:00 1970 +0000)