[PATCH 12 of 16] obsolescence: add test case B-3 for obsolescence markers exchange

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at ens-lyon.org>
# Date 1491835613 -7200
#      Mon Apr 10 16:46:53 2017 +0200
# Node ID 36b221d05d70938eb2e436a9c0838b1de9ee7f8a
# Parent  8857ebacad1d7cb2e54d2714d2d27f155dfdfd53
# EXP-Topic exchange.obsmarkers
# Available At https://www.mercurial-scm.org/repo/users/marmoute/mercurial/
#              hg pull https://www.mercurial-scm.org/repo/users/marmoute/mercurial/ -r 36b221d05d70
obsolescence: add test case B-3 for obsolescence markers exchange

About 3 years ago, in August 2014, the logic to select what markers to select on
push was ported from the evolve extension to Mercurial core. However, for some
unclear reasons, the tests for that logic were not ported alongside.
I realised it a couple of weeks ago while working on another push related issue.
I've made a clean up pass on the tests and they are now ready to integrate the
core test suite. This series of changesets do not change any logic. I just adds
test for logic that has been around for about 10 versions of Mercurial.

They are a patch for each test case. It makes it easier to review and postpone
one with documentation issues without rejecting the wholes series.

This patch introduce case B3: Pruned changeset on non-pushed part of the history

Each test case comes it in own test file. It help parallelism and does not
introduce a significant overhead from having a single unified giant test file.
Here are timing  to support this claim.

# Multiple test files version:
# run-tests.py --local -j 1 test-exchange-*.t
53.40s user 6.82s system 85% cpu 1:10.76 total
52.79s user 6.97s system 85% cpu 1:09.97 total
52.94s user 6.82s system 85% cpu 1:09.69 total

# Single test file version:
# run-tests.py --local -j 1 test-exchange-obsmarkers.t
52.97s user 6.85s system 85% cpu 1:10.10 total
52.64s user 6.79s system 85% cpu 1:09.63 total
53.70s user 7.00s system 85% cpu 1:11.17 total

diff --git a/tests/test-exchange-obsmarkers-case-B3.t b/tests/test-exchange-obsmarkers-case-B3.t
new file mode 100644
--- /dev/null
+++ b/tests/test-exchange-obsmarkers-case-B3.t
@@ -0,0 +1,115 @@
+============================================
+Testing obsolescence markers push: Cases B.3
+============================================
+
+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 3: Pruned changeset on non-pushed part of the history
+
+B.3 Pruned changeset on non-pushed part of the history
+======================================================
+
+.. {{{
+..   ⊗ C
+..   |
+..   ○ B
+..   | ◔ A
+..   |/
+..   ● O
+.. }}}
+..
+.. Marker exists from:
+..
+..  * C (prune)
+..
+.. Commands run:
+..
+..  * hg push -r A
+..
+.. Expected exchange:
+..
+..  * ø
+..
+.. Expected exclude:
+..
+..  * chain from B
+
+Setup
+-----
+
+  $ . $TESTDIR/testlib/exchange-obsmarker-util.sh
+
+initial
+
+  $ setuprepos B.3
+  creating test repo for test case B.3
+  - pulldest
+  - main
+  - pushdest
+  cd into `main` and proceed with env setup
+  $ cd main
+  $ mkcommit A
+  $ hg up --quiet 0
+  $ mkcommit B
+  created new head
+  $ mkcommit C
+  $ hg prune -qd '0 0' .
+  $ hg log -G --hidden
+  x  e56289ab6378 (draft): C
+  |
+  @  35b183996678 (draft): B
+  |
+  | o  f5bc6836db60 (draft): A
+  |/
+  o  a9bdc8b26820 (public): O
+  
+  $ inspect_obsmarkers
+  obsstore content
+  ================
+  e56289ab6378dc752fd7965f8bf66b58bda740bd 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
+  $ cd ..
+  $ cd ..
+
+Actual Test
+-----------------------------------
+
+  $ dotest B.3 A
+  ## Running testcase B.3
+  # testing echange of "A" (f5bc6836db60)
+  ## initial state
+  # obstore: main
+  e56289ab6378dc752fd7965f8bf66b58bda740bd 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
+  # obstore: pushdest
+  # obstore: pulldest
+  ## pushing "A" from main to pushdest
+  pushing to pushdest
+  searching for changes
+  remote: adding changesets
+  remote: adding manifests
+  remote: adding file changes
+  remote: added 1 changesets with 1 changes to 1 files
+  ## post push state
+  # obstore: main
+  e56289ab6378dc752fd7965f8bf66b58bda740bd 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
+  # obstore: pushdest
+  # obstore: pulldest
+  ## pulling "f5bc6836db60" from main into pulldest
+  pulling from main
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files
+  (run 'hg update' to get a working copy)
+  ## post pull state
+  # obstore: main
+  e56289ab6378dc752fd7965f8bf66b58bda740bd 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
+  # obstore: pushdest
+  # obstore: pulldest
+