tests/fakemergerecord.py

wireproto: use CBOR for command requests

Now that we're using CBOR in the new wire protocol, let's convert
command requests to it.

Before I wrote this patch and was even thinking about CBOR, I was
thinking about how commands should be issued and came to the
conclusion that we didn't need separate frames to represent the
command name from its arguments. I already had a partially
completed patch prepared to merge the frames.

But with CBOR, it makes the implementation a bit simpler because
we don't need to roll our own serialization.

The changes here are a bit invasive. I tried to split this into
multiple commits to make it easier to review. But it was just too
hard.

* "command name" and "command argument" frames have been collapsed
  into a "command request" frame.
* The flags for this new frame are totally different.
* Frame processing has been overhauled to reflect the new order
  of things.
* Test fallout was significant. A handful of tests were removed.

Altogether, I think the new code is simpler. We don't have
complicated state around receiving commands. We're either receiving
command request frames or command data frames. We /could/
potentially collapse command data frames into command request
frames. Although I'd have to think a bit more about this before
I do it.

Differential Revision: https://phab.mercurial-scm.org/D2951

# Extension to write out fake unsupported records into the merge state
#
#

from __future__ import absolute_import

from mercurial import (
    merge,
    registrar,
)

cmdtable = {}
command = registrar.command(cmdtable)

@command(b'fakemergerecord',
         [(b'X', b'mandatory', None, b'add a fake mandatory record'),
          (b'x', b'advisory', None, b'add a fake advisory record')], '')
def fakemergerecord(ui, repo, *pats, **opts):
    with repo.wlock():
        ms = merge.mergestate.read(repo)
        records = ms._makerecords()
        if opts.get('mandatory'):
            records.append((b'X', b'mandatory record'))
        if opts.get('advisory'):
            records.append((b'x', b'advisory record'))
        ms._writerecords(records)