tests/test-push-checkheads-unpushed-D6.t

commit: remove special handling of IOError (actually dead code)

In the past, IOError was used to mark a file as removed. The differentiation
between OSError and IOError in this place was introduced in e553a425751d, to
avoid that “normal” OSErrors / IOErrors accidentally mark files as removed.
This weird internal API was removed in 650b5b6e75ed. It seems like that
changeset should have removed the differentiation, at least I don’t see any
reason for keeping it.

On Python 3, OSError and IOError are aliased. Therefore the removed code was
actually dead.

====================================
Testing head checking code: Case D-6
====================================

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 D: remote head is "obs-affected" locally, but result is not part of the push
TestCase 6: single changeset, superseeded then pruned (on a new changeset unpushed) changeset

This is a partial push variation of case B-6

.. old-state:
..
.. * 1 changeset branch
..
.. new-state:
..
.. * old branch is rewritten onto another one,
.. * the new version is then pruned.
..
.. expected-result:
..
.. * push denied
..
.. graph-summary:
..
..   A ø⇠⊗ A'
..     | |
.. C ◔ | ○ B
..    \|/
..     ●

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

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

  $ mkdir D6
  $ cd D6
  $ setuprepos
  creating basic server and client repo
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd client
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mkcommit B0
  created new head
  $ mkcommit A1
  $ hg up '0'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ mkcommit C0
  created new head
  $ hg debugobsolete `getid "desc(A0)"` `getid "desc(A1)"`
  1 new obsolescence markers
  obsoleted 1 changesets
  $ hg debugobsolete --record-parents `getid "desc(A1)"`
  1 new obsolescence markers
  obsoleted 1 changesets
  $ hg log -G --hidden
  @  0f88766e02d6 (draft): C0
  |
  | x  ba93660aff8d (draft): A1
  | |
  | o  74ff5441d343 (draft): B0
  |/
  | x  8aaa48160adc (draft): A0
  |/
  o  1e4be0697311 (public): root
  

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

  $ hg push --rev 'desc(C0)'
  pushing to $TESTTMP/D6/server
  searching for changes
  abort: push creates new remote head 0f88766e02d6
  (merge or see 'hg help push' for details about pushing new heads)
  [20]

  $ cd ../..