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 python
"""
Small and dumb HTTP server for use in tests.
"""
import optparse
import os
import signal
import socket
import sys
from mercurial import (
encoding,
pycompat,
server,
util,
)
httpserver = util.httpserver
OptionParser = optparse.OptionParser
if os.environ.get('HGIPV6', '0') == '1':
class simplehttpserver(httpserver.httpserver):
address_family = socket.AF_INET6
else:
simplehttpserver = httpserver.httpserver
class _httprequesthandler(httpserver.simplehttprequesthandler):
def log_message(self, format, *args):
httpserver.simplehttprequesthandler.log_message(self, format, *args)
sys.stderr.flush()
class simplehttpservice:
def __init__(self, host, port):
self.address = (host, port)
def init(self):
self.httpd = simplehttpserver(self.address, _httprequesthandler)
def run(self):
self.httpd.serve_forever()
if __name__ == '__main__':
parser = OptionParser()
parser.add_option(
'-p',
'--port',
dest='port',
type='int',
default=8000,
help='TCP port to listen on',
metavar='PORT',
)
parser.add_option(
'-H',
'--host',
dest='host',
default='localhost',
help='hostname or IP to listen on',
metavar='HOST',
)
parser.add_option('--logfile', help='file name of access/error log')
parser.add_option(
'--pid',
dest='pid',
help='file name where the PID of the server is stored',
)
parser.add_option(
'-f',
'--foreground',
dest='foreground',
action='store_true',
help='do not start the HTTP server in the background',
)
parser.add_option('--daemon-postexec', action='append')
(options, args) = parser.parse_args()
signal.signal(signal.SIGTERM, lambda x, y: sys.exit(0))
if options.foreground and options.logfile:
parser.error(
"options --logfile and --foreground are mutually " "exclusive"
)
if options.foreground and options.pid:
parser.error("options --pid and --foreground are mutually exclusive")
opts = {
b'pid_file': options.pid,
b'daemon': not options.foreground,
b'daemon_postexec': pycompat.rapply(
encoding.strtolocal, options.daemon_postexec
),
}
service = simplehttpservice(options.host, options.port)
runargs = [sys.executable, __file__] + sys.argv[1:]
runargs = [pycompat.fsencode(a) for a in runargs]
server.runservice(
opts,
initfn=service.init,
runfn=service.run,
logfile=options.logfile,
runargs=runargs,
)