tests/test-push-checkheads-pruned-B5.t

phabricator: warn if unable to amend, instead of aborting after posting

There was a divergence in behavior here between obsolete and strip based
amending.  I first noticed the abort when testing outside of the test harness,
but then had trouble recreating it here after reverting the code changes.  It
turns out, strip based amend was successfully amending the public commit after
it was posted!  It looks like the protection is in the `commit --amend` command,
not in the underlying code that it calls.

I considered doing a preflight check and aborting.  But the locks are only
acquired at the end, if amending, and this is too large a section of code to be
wrapped in a maybe-it's-held-or-not context manager for my tastes.
Additionally, some people do post-push reviews, and amending is the default
behavior, so they shouldn't see a misleading error message.

The lack of a 'Differential Revision' entry in the commit message breaks a
{phabreview} test, so it had to be partially conditionalized.

====================================
Testing head checking code: Case B-5
====================================

Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.

This case is part of a series of tests checking this behavior.

Category B: simple case involving pruned changesets
TestCase 5: multi-changeset branch, mix of pruned and superceeded

.. old-state:
..
.. * 3 changeset branch
..
.. new-state:
..
.. * old head is pruned
.. * old mid is superceeded
.. * old root is pruned
..
.. expected-result:
..
.. * push allowed
..
.. graph-summary:
..
..   B ⊗
..     |
..   A ø⇠◔ A'
..     | |
..   B ⊗ |
..     |/
..     ●

  $ . $TESTDIR/testlib/push-checkheads-util.sh

Test setup
----------

  $ mkdir B5
  $ cd B5
  $ setuprepos
  creating basic server and client repo
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd server
  $ mkcommit B0
  $ mkcommit C0
  $ cd ../client
  $ hg pull
  pulling from $TESTTMP/B5/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets d73caddc5533:821fb21d0dd2 (2 drafts)
  (run 'hg update' to get a working copy)
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mkcommit B1
  created new head
  $ hg debugobsolete --record-parents `getid "desc(A0)"`
  obsoleted 1 changesets
  2 new orphan changesets
  $ hg debugobsolete `getid "desc(B0)"` `getid "desc(B1)"`
  obsoleted 1 changesets
  $ hg debugobsolete --record-parents `getid "desc(C0)"`
  obsoleted 1 changesets
  $ hg log -G --hidden
  @  25c56d33e4c4 (draft): B1
  |
  | x  821fb21d0dd2 (draft): C0
  | |
  | x  d73caddc5533 (draft): B0
  | |
  | x  8aaa48160adc (draft): A0
  |/
  o  1e4be0697311 (public): root
  

Actual testing
--------------

  $ hg push
  pushing to $TESTTMP/B5/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  3 new obsolescence markers
  obsoleted 3 changesets

  $ cd ../..