hg

setup: only write some autogenerated files if they change

Without this change, setup.py always writes some files on every
invocation. This prevents some builds from being a no-op when they
should. And, since times can sneak into generated .pyc files,
this prevents file content from being deterministic between
builds.

As part of the refactor, we treat file content as bytes.

The only potential regression from this would be if some tool
is looking at mtimes of the changed files to determine if
further action should be taken. But I don't think anything
critically important is keyed off the mtimes of these specific files.

Differential Revision: https://phab.mercurial-scm.org/D1580

#!/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.
from __future__ import absolute_import

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)

from mercurial import dispatch
dispatch.run()