branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
#!/usr/bin/env python3
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 Olivia Mackall <olivia@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.
import os
import sys
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)
# Make `pip install --user ...` packages available to the official Windows
# build. Most py2 packaging installs directly into the system python
# environment, so no changes are necessary for other platforms. The Windows
# py2 package uses py2exe, which lacks a `site` module. Hardcode it according
# to the documentation.
if getattr(sys, 'frozen', None) == 'console_exe':
vi = sys.version_info
appdata = os.environ.get('APPDATA')
if appdata:
sys.path.append(
os.path.join(
appdata,
'Python',
'Python%d%d' % (vi[0], vi[1]),
'site-packages',
)
)
try:
from hgdemandimport import tracing
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)
with tracing.log('hg script'):
# enable importing on demand to reduce startup time
import hgdemandimport
hgdemandimport.enable()
from mercurial import dispatch
dispatch.run()