tests/test-exchange-obsmarkers-case-A4.t

context: introduce p[12]copies() methods and debugp[12]copies commands

As mentioned earlier, I'm working on support for storing copy metadata
in the changeset instead of in the filelog.

In order to transition a repo from storing metadata in filelogs to
storing it in the changeset, I'm going to provide a config option for
reading the metadata from the changeset, but falling back to getting
it from the filelog if it's not in the changeset. In this compatiblity
mode, the changeset-optmized algorithms will be used. We will then
need to convert the filelog copy metadata to look like that provided
by changeset copy metadata. This patch introduces methods that do just
that.

By having these methods here, we can start writing changeset-optimized
algorithms that should work already before we add any support for
storing the metadata in the changesets.

This commit also includes new debugp[12]copies commands and exercises
them in test-copies.t.

Differential Revision: https://phab.mercurial-scm.org/D5990

============================================
Testing obsolescence markers push: Cases A.4
============================================

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 A: simple cases
Testcase 4: Push in the middle of the obsolescence chain

A.4 Push in the middle of the obsolescence chain
================================================

.. (Where we show that we should not push the marker without the successors)
..
.. {{{
..   B ◔
..     |
..   A⇠ø⇠○ A'
..     |/
..     ● O
.. }}}
..
.. Markers exist from:
..
..  * `A ø⇠○ A'`
..  * chain from A
..
.. Command runs:
..
..  * hg push -r B
..
.. Expected exchange:
..
..  * Chain from A
..
.. Expected Exclude:
..
..  * `Ai ø⇠○ A'`

Setup
-----

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

initial

  $ setuprepos A.4
  creating test repo for test case A.4
  - pulldest
  - main
  - pushdest
  cd into `main` and proceed with env setup
  $ cd main
  $ mkcommit A0
  $ mkcommit B
  $ hg update 0
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ mkcommit A1
  created new head
  $ hg debugobsolete aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa `getid 'desc(A0)'`
  $ hg debugobsolete `getid 'desc(A0)'` `getid 'desc(A1)'`
  obsoleted 1 changesets
  1 new orphan changesets
  $ hg log -G --hidden
  @  e5ea8f9c7314 (draft): A1
  |
  | *  06055a7959d4 (draft): B
  | |
  | x  28b51eb45704 (draft): A0
  |/
  o  a9bdc8b26820 (public): O
  
  $ inspect_obsmarkers
  obsstore content
  ================
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  $ cd ..
  $ cd ..

Actual Test for first version
-----------------------------

  $ dotest A.4 B -f
  ## Running testcase A.4
  # testing echange of "B" (06055a7959d4)
  ## initial state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest
  ## pushing "B" from main to pushdest
  pushing to pushdest
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 2 changesets with 2 changes to 2 files
  remote: 1 new obsolescence markers
  ## post push state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  ## pulling "06055a7959d4" from main into pulldest
  pulling from main
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  1 new obsolescence markers
  new changesets 28b51eb45704:06055a7959d4 (2 drafts)
  (run 'hg update' to get a working copy)
  ## post pull state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f e5ea8f9c73143125d36658e90ef70c6d2027a5b7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 28b51eb45704506b5c603decd6bf7ac5e0f6a52f 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}