view tests/test-push-checkheads-partial-C2.t @ 42943:5fadf6103790

remotefilelog: replace repack lock to solve race condition

2c74337e6483 reduced the probability of race-conditions when starting
background repack and prefetch and we saw the difference in our CI instance
with all failures disappearing except one where one call to waitonrepack seems
to returns too early.

I'm not sure what exactly goes wrong but I realized that while the prefetch
operation uses a standard Mercurial lock, the repack operation is using a
custom lock based on `fcntl.flock` on available platforms. As `extutil.flock`
fallback on traditional Mercurial locks on other platforms and the tests are
stable on my laptop, our CI environment and GCC112, I'm sending this patch to
standardize the behavior across environments.

Differential Revision: https://phab.mercurial-scm.org/D6844

====================================
Testing head checking code: Case C-2
====================================

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 C: case were the branch is only partially obsoleted
TestCase 2: 2 changeset branch, only the base is rewritten

.. old-state:
..
.. * 2 changeset branch
..
.. new-state:
..
.. * 1 new changesets branches superceeding only the base of the old one
.. * The old branch is still alive (base is obsolete, head is alive)
..
.. expected-result:
..
.. * push denied
..
.. graph-summary:
..
..   B ○
..     |
..   A ø⇠◔ A'
..     |/
..     ●

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

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

  $ mkdir C2
  $ cd C2
  $ 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/C2/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets d73caddc5533 (1 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 A1
  created new head
  $ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`
  1 new obsolescence markers
  obsoleted 1 changesets
  1 new orphan changesets
  $ hg log -G --hidden
  @  f6082bc4ffef (draft): A1
  |
  | *  d73caddc5533 (draft): B0
  | |
  | x  8aaa48160adc (draft): A0
  |/
  o  1e4be0697311 (public): root
  

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

  $ hg push --rev 'desc(A1)'
  pushing to $TESTTMP/C2/server
  searching for changes
  abort: push creates new remote head f6082bc4ffef!
  (merge or see 'hg help push' for details about pushing new heads)
  [255]

  $ cd ../..