view tests/test-push-checkheads-pruned-B3.t @ 37787:92213f6745ed

rebase: introduce support for automatically rebasing orphan changes

_destautorebase(SRC) is based on the _destrestack(SRC) revset from
fbamend. The supporting _possibledestination function is extracted
from evolve, with minor cleanups.

We've considered some alternatives here:
 * This change, but with --auto as the flag name. We're hedging our bets
   on this a little in this change so that if this ends up being the wrong
   direction we haven't burned the valauble --auto name on rebase.
 * --destination auto: I've got reservations about the discoverability of this,
   and we don't currently have a good story for a revset alias of sorts that
   changes behavior depending on the context in which it's used.
 * A "rebase presets" feature, where we could use the currently-an-error
   positional argument space for the rebase command to define presets, so that
   users could define a 'linearize' preset that specifies
   --revision='orphan()-obsolete()' and --dest=_destautoorphanrebase(SRC).

Personally, I find the third option somewhat appealing, but am
hesitant to "spend" the functionality space of positional arguments to
the rebase command. We should revisit the way we expose this
functionality sometime in the 4.7 cycle once we've had a chance to vet
the implementation of the functionality.

Differential Revision: https://phab.mercurial-scm.org/D2668

====================================
Testing head checking code: Case B-3
====================================

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 3: multi-changeset branch, other is pruned, rest is superceeded

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

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

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

  $ mkdir B3
  $ cd B3
  $ 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
  $ cd ../client
  $ hg pull
  pulling from $TESTTMP/B3/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets d73caddc5533
  (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
  1 new orphan changesets
  $ hg debugobsolete `getid "desc(B0)" ` `getid "desc(B1)"`
  obsoleted 1 changesets
  $ hg log -G --hidden
  @  25c56d33e4c4 (draft): B1
  |
  | x  d73caddc5533 (draft): B0
  | |
  | x  8aaa48160adc (draft): A0
  |/
  o  1e4be0697311 (public): root
  

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

  $ hg push
  pushing to $TESTTMP/B3/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  2 new obsolescence markers
  obsoleted 2 changesets

  $ cd ../..