view hg @ 33137:31ab1912678a

obsolete: skip 'changectx' usage in unstable computation

We simplify the unstable computation code, skipping the expensive creation of
changectx object. We focus on efficient set operation and revnumber centric
functions.

In my mercurial development repository, this provides a 3x speedup to the
function:

  before: 5.319 ms
  after:  1.844 ms

repo details:

  total changesets:       40886
  obsolete changesets:     7756
  mutable (not obsolete):   293
  unstable:                  30

#!/usr/bin/env python
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 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.

import os
import sys

if os.environ.get('HGUNICODEPEDANTRY', False):
    try:
        reload(sys)
        sys.setdefaultencoding("undefined")
    except NameError:
        pass

libdir = '@LIBDIR@'

if libdir != '@' 'LIBDIR' '@':
    if not os.path.isabs(libdir):
        libdir = os.path.join(os.path.dirname(os.path.realpath(__file__)),
                              libdir)
        libdir = os.path.abspath(libdir)
    sys.path.insert(0, libdir)

# enable importing on demand to reduce startup time
try:
    if sys.version_info[0] < 3 or sys.version_info >= (3, 6):
        import hgdemandimport; hgdemandimport.enable()
except ImportError:
    sys.stderr.write("abort: couldn't find mercurial libraries in [%s]\n" %
                     ' '.join(sys.path))
    sys.stderr.write("(check your install and PYTHONPATH)\n")
    sys.exit(-1)

import mercurial.util
import mercurial.dispatch

for fp in (sys.stdin, sys.stdout, sys.stderr):
    mercurial.util.setbinary(fp)

mercurial.dispatch.run()