tests/test-revert-flags.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.

#require execbit

  $ hg init repo
  $ cd repo
  $ echo foo > foo
  $ chmod 644 foo
  $ hg ci -qAm '644'

  $ chmod 755 foo
  $ hg ci -qAm '755'

reverting to rev 0

  $ hg revert -a -r 0
  reverting foo
  $ hg st
  M foo
  $ hg diff --git
  diff --git a/foo b/foo
  old mode 100755
  new mode 100644

  $ cd ..