view mercurial/node.py @ 27592:7c9eb2927879

dirstate: add a C implementation for nonnormalentries

Before this patch, there was only a python version of nonnormalentries.
On mozilla-central we have a 10x win by putting this function in C:
% python -m timeit -s \
        'from mercurial import hg, ui, parsers; \
        repo = hg.repository(ui.ui(), "mozilla-central"); \
        m = repo.dirstate._map' \
        'parsers.nonnormalentries(m)'

100 loops, best of 3: 3.15 msec per loop

The python implementation runs in 31ms, a similar test gives:
10 loops, best of 3: 31.7 msec per loop

On our big repos, the win is still of 10x with the python implementation running
in 350ms and the C implementation running in 30ms.

# 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])