# node.py - basic nodeid manipulation for mercurial

#

# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>

#

# 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

# Adapt to Python 3 API changes. If this ends up showing up in

# profiles, we can use this version only on Python 3, and forward

# binascii.unhexlify like we used to on Python 2.

def bin(s):

    try:

        return binascii.unhexlify(s)

    except binascii.Error as e:

        raise TypeError(e)

nullrev = -1

nullid = b"\0" * 20

nullhex = hex(nullid)

# Phony node value to stand-in for new files in some uses of

# manifests.

newnodeid = '!' * 20

addednodeid = ('0' * 15) + 'added'

modifiednodeid = ('0' * 12) + 'modified'

wdirnodes = {newnodeid, addednodeid, modifiednodeid}

# pseudo identifiers for working directory

# (they are experimental, so don't add too many dependencies on them)

wdirrev = 0x7fffffff

wdirid = b"\xff" * 20

wdirhex = hex(wdirid)

def short(node):

    return hex(node[:6])