view mercurial/node.py @ 27928:c0f11347b107 stable

changegroup: don't support versions 01 and 02 with treemanifests

Since it would be terribly expensive to convert between flat manifests
and treemanifests, we have decided to simply not support changegroup
version 01 and 02 with treemanifests. Therefore, let's stop announcing
that we support these versions on treemanifest repos.

Note that this means that older clients that try to clone from a
treemanifest repo will fail. What happens is that the server, after
this patch, finds that there are no common versions and raises
"ValueError: no common changegroup version". This results in "abort:
HTTP Error 500: Internal Server Error" on the client.

Before this patch, it was no better: The server would instead find
that there were directory manifest nodes to put in the changegroup 01
or 02 and raise an AssertionError on changegroup.py#668 (assert not
tmfnodes), which would also appear as a 500 to the client.

# node.py - basic nodeid manipulation for mercurial
#
# Copyright 2005, 2006 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import binascii

# This ugly style has a noticeable effect in manifest parsing
hex = binascii.hexlify
bin = binascii.unhexlify

nullrev = -1
nullid = "\0" * 20
nullhex = hex(nullid)

# pseudo identifiers for working directory
# (they are experimental, so don't add too many dependencies on them)
wdirrev = 0x7fffffff
wdirid = "\xff" * 20

def short(node):
    return hex(node[:6])