tests/test-abort-checkin.t

bundle2: make server.bundle2.stream default to True

Support for bundle2 streaming clones has been shipped in Mercurial 4.5
(7eedbd5d4880), but was never activated by default. It's time to have more
people use it. The new format allows streaming clones to transport cache
(hooray for speed) and phaseroots (fixes phase-related issues).

Changes in tests:

bundle2 capabilities now have "stream=v2" (plus a '\n' as a separator) and
therefore take 14 bytes more: "%0Astream%3Dv2". Tip for tests that have data
encoded with CBOR: 0xd3 - 0xc5 = 14.

$USUAL_BUNDLE2_CAPS$ replaces $USUAL_BUNDLE2_CAPS_SERVER$, which is the same
thing, but without "stream=v2".

Since streaming clones now also transfer caches, the reported byte and file
counts are higher (e.g. 816 bytes in 9 files instead of 613 bytes in 4 files,
a bit of --debug and manual math confirms that the caches take these extra 203
bytes in 5 files).

Differential Revision: https://phab.mercurial-scm.org/D4680

  $ cat > abortcommit.py <<EOF
  > from mercurial import error
  > def hook(**args):
  >     raise error.Abort(b"no commits allowed")
  > def reposetup(ui, repo):
  >     repo.ui.setconfig(b"hooks", b"pretxncommit.nocommits", hook)
  > EOF
  $ abspath=`pwd`/abortcommit.py

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > mq =
  > abortcommit = $abspath
  > EOF

  $ hg init foo
  $ cd foo
  $ echo foo > foo
  $ hg add foo

mq may keep a reference to the repository so __del__ will not be
called and .hg/journal.dirstate will not be deleted:

  $ hg ci -m foo
  error: pretxncommit.nocommits hook failed: no commits allowed
  transaction abort!
  rollback completed
  abort: no commits allowed
  [255]
  $ hg ci -m foo
  error: pretxncommit.nocommits hook failed: no commits allowed
  transaction abort!
  rollback completed
  abort: no commits allowed
  [255]

  $ cd ..