tests/test-exchange-obsmarkers-case-B5.t

help: revise explanation about capability check while selecting merge tool

This is follow up of 7c6044634957 and cded904f7acc.

This patch adds explanations about:

  - notation in capability columns in the table
  - how capabilities of external merge tools are treated

============================================
Testing obsolescence markers push: Cases B.5
============================================

Mercurial pushes obsolescences markers relevant to the "pushed-set", the set of
all changesets that requested to be "in sync" after the push (even if they are
already on both side).

This test belongs to a series of tests checking such set is properly computed
and applied. This does not tests "obsmarkers" discovery capabilities.

Category B: pruning case
TestCase 5: Push of a children of changeset which successors is pruned

B.5 Push of a children of changeset which successors is pruned
==============================================================

.. This case Mirror A.4, with pruned changeset successors.
..
.. {{{
..   C ◔
..     |
..   B⇠ø⇠⊗ B'
..     | |
..   A ø⇠○ A'
..     |/
..     ●
.. }}}
..
.. Marker exist from:
..
..  * `A ø⇠○ A'`
..  * `B ø⇠○ B'`
..  * chain from B
..  * `B' is pruned`
..
.. Command run:
..
..  * hg push -r C
..
.. Expected exchange:
..
..  * chain from B
..
.. Expected exclude:
..
..  * `A ø⇠○ A'`
..  * `B ø⇠○ B'`
..  * `B' prune`

Setup
-----

  $ . $TESTDIR/testlib/exchange-obsmarker-util.sh

initial

  $ setuprepos B.5
  creating test repo for test case B.5
  - pulldest
  - main
  - pushdest
  cd into `main` and proceed with env setup
  $ cd main
  $ mkcommit A0
  $ mkcommit B0
  $ mkcommit C
  $ hg up --quiet 0
  $ mkcommit A1
  created new head
  $ mkcommit B1
  $ hg debugobsolete --hidden `getid 'desc(A0)'` `getid 'desc(A1)'`
  obsoleted 1 changesets
  2 new orphan changesets
  $ hg debugobsolete --hidden aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa `getid 'desc(B0)'`
  $ hg debugobsolete --hidden `getid 'desc(B0)'` `getid 'desc(B1)'`
  obsoleted 1 changesets
  $ hg prune -qd '0 0' 'desc(B1)'
  $ hg log -G --hidden
  x  069b05c3876d (draft): B1
  |
  @  e5ea8f9c7314 (draft): A1
  |
  | *  1d0f3cd25300 (draft): C
  | |
  | x  6e72f0a95b5e (draft): B0
  | |
  | x  28b51eb45704 (draft): A0
  |/
  o  a9bdc8b26820 (public): O
  
  $ inspect_obsmarkers
  obsstore content
  ================
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 069b05c3876d56f62895e853a501ea58ea85f68d 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  069b05c3876d56f62895e853a501ea58ea85f68d 0 {e5ea8f9c73143125d36658e90ef70c6d2027a5b7} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  $ cd ..
  $ cd ..

Actual Test (explicit push version)
-----------------------------------

  $ dotest B.5 C -f
  ## Running testcase B.5
  # testing echange of "C" (1d0f3cd25300)
  ## initial state
  # obstore: main
  069b05c3876d56f62895e853a501ea58ea85f68d 0 {e5ea8f9c73143125d36658e90ef70c6d2027a5b7} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 069b05c3876d56f62895e853a501ea58ea85f68d 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest
  ## pushing "C" from main to pushdest
  pushing to pushdest
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 3 changesets with 3 changes to 3 files
  remote: 1 new obsolescence markers
  ## post push state
  # obstore: main
  069b05c3876d56f62895e853a501ea58ea85f68d 0 {e5ea8f9c73143125d36658e90ef70c6d2027a5b7} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 069b05c3876d56f62895e853a501ea58ea85f68d 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  ## pulling "1d0f3cd25300" from main into pulldest
  pulling from main
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 3 changes to 3 files
  1 new obsolescence markers
  new changesets 28b51eb45704:1d0f3cd25300
  (run 'hg update' to get a working copy)
  ## post pull state
  # obstore: main
  069b05c3876d56f62895e853a501ea58ea85f68d 0 {e5ea8f9c73143125d36658e90ef70c6d2027a5b7} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 069b05c3876d56f62895e853a501ea58ea85f68d 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 6e72f0a95b5e01a7504743aa941f69cb1fbef8b0 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}