annotate tests/test-evolve-content-divergent-case-A2.t @ 6935:954d7ea5cd67 stable tip

stack: when stack base is obsolete, pick any successor, even if at random

There are situations when s0 is obsolete and we also cannot pick just one
successor for it to use in stack. In such a case, let's pick the "latest"
successor from the first set.

We're assuming that obsutil.successorssets() returns data in the same order (it
should, since it makes sure to sort data internally). Keeping that in mind,
while the successor picked for s0 by this code is not based on any sort of
sophisticated logic, it should nonetheless be the same every time.

This patch is probably not going to completely break anything that was
previously working fine, because the previous behavior was to just abort with
an exception.

===============================================
Testing content-divergence resolution: Case A.2
===============================================

Independent rewrites of same changeset can lead to content-divergence. In most
common cases, it can occur when multiple users rewrite the same changeset
independently and push it.

This test belongs to a series of tests checking the resolution of content-divergent
changesets.

Category A: no parents are obsolete
Testcase 2: no conflict: both sides amended content changes (non-conflicting changes in same file)

A.2 both sides amended content changes
======================================

.. (Divergence reason):
..    local: amended some content changes in same file as "other" but non-conflicting
..    other: amended some content changes in same file as "local" but non-conflicting
.. Where we show that since both side amended some content changes without any relocation,
.. the most reasonable behaviour is to simply perform 3-way merge.
..
.. (local):
..
..   A ø⇠○ A'
..     |/
..     ● O
..
.. (other):
..
..   A ø⇠○ A''
..     |/
..     ● O
..
.. (Resolution):
..
..     ○ A'''
..     |
..     ● O
..

Setup
-----
  $ . $TESTDIR/testlib/content-divergence-util.sh
  $ setuprepos A.2
  creating test repo for test case A.2
  - upstream
  - local
  - other
  cd into `local` and proceed with env setup

initial

  $ cd local
  $ mkcommit A0
  $ hg push -q
  $ sed -i '1ifoo' A0
  $ hg amend -m "A1"
  $ hg log -G --hidden
  @  2:e1f7c24563ba (draft): A1
  |
  | x  1:28b51eb45704 (draft): A0
  |/
  o  0:a9bdc8b26820 (public): O
  
  $ cd ../other
  $ hg pull -uq
  $ echo bar >> A0
  $ hg amend
  $ hg push -q

  $ cd ../local
  $ hg pull -q
  2 new content-divergent changesets

Actual test of resolution
-------------------------
  $ hg evolve -l
  e1f7c24563ba: A1
    content-divergent: 5fbe90f37421 (draft) (precursor 28b51eb45704)
  
  5fbe90f37421: A0
    content-divergent: e1f7c24563ba (draft) (precursor 28b51eb45704)
  
  $ hg log -G --hidden
  *  3:5fbe90f37421 (draft): A0 [content-divergent]
  |
  | @  2:e1f7c24563ba (draft): A1 [content-divergent]
  |/
  | x  1:28b51eb45704 (draft): A0
  |/
  o  0:a9bdc8b26820 (public): O
  

  $ hg evolve --content-divergent
  merge:[2] A1
  with: [3] A0
  base: [1] A0
  merging A0
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  working directory is now at 414367a5568a

  $ hg log -Gp
  @  4:414367a5568a (draft): A1
  |  diff -r a9bdc8b26820 -r 414367a5568a A0
  |  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  |  +++ b/A0	Thu Jan 01 00:00:00 1970 +0000
  |  @@ -0,0 +1,3 @@
  |  +foo
  |  +A0
  |  +bar
  |
  o  0:a9bdc8b26820 (public): O
     diff -r 000000000000 -r a9bdc8b26820 O
     --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     +++ b/O	Thu Jan 01 00:00:00 1970 +0000
     @@ -0,0 +1,1 @@
     +O
  
  $ hg evolve -l