push: rework the computation of fallbackheads to be correct
The previous computation tried to be smart but ended up being wrong. This was
caught by phase movement test while reworking the phase discovery logic to be
faster.
The previous logic was failing to catch case where the pushed set was not based
on a common heads (i.e. when the discovery seemed to have "over discovered"
content, outside the pushed set)
In the following graph, `e` is a common head and we `hg push -r f`. We need to
detect `c` as a fallback heads and we previous failed to do so::
e
|
d f
|/
c
|
b
|
a
The performance impact of the change seems minimal. On the most impacted
repository at hand (mozilla-try), the slowdown seems mostly mixed in the
overall noise `hg push` but seems to be in the hundred of milliseconds order of
magnitude. When using rust, we seems to be a bit faster, probably because we
leverage more accelaratd internals.
I added a couple of performance related common for further investigation later
on.
#!/usr/bin/env python
"""This does HTTP requests (GET by default) given a host:port and path and
returns a subset of the headers plus the body of the result."""
import argparse
import json
import os
import sys
from mercurial import (
pycompat,
util,
)
httplib = util.httplib
try:
import msvcrt
msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
except ImportError:
pass
stdout = getattr(sys.stdout, 'buffer', sys.stdout)
parser = argparse.ArgumentParser()
parser.add_argument('--twice', action='store_true')
parser.add_argument('--headeronly', action='store_true')
parser.add_argument('--json', action='store_true')
parser.add_argument('--hgproto')
parser.add_argument(
'--requestheader',
nargs='*',
default=[],
help='Send an additional HTTP request header. Argument '
'value is <header>=<value>',
)
parser.add_argument('--bodyfile', help='Write HTTP response body to a file')
parser.add_argument('--method', default='GET', help='HTTP method to use')
parser.add_argument('host')
parser.add_argument('path')
parser.add_argument('show', nargs='*')
args = parser.parse_args()
twice = args.twice
headeronly = args.headeronly
formatjson = args.json
hgproto = args.hgproto
requestheaders = args.requestheader
tag = None
def request(method, host, path, show):
assert not path.startswith('/'), path
global tag
headers = {}
if tag:
headers['If-None-Match'] = tag
if hgproto:
headers['X-HgProto-1'] = hgproto
for header in requestheaders:
key, value = header.split('=', 1)
headers[key] = value
conn = httplib.HTTPConnection(host)
conn.request(method, '/' + path, None, headers)
response = conn.getresponse()
stdout.write(
b'%d %s\n' % (response.status, response.reason.encode('ascii'))
)
if show[:1] == ['-']:
show = sorted(
h for h, v in response.getheaders() if h.lower() not in show
)
for h in [h.lower() for h in show]:
if response.getheader(h, None) is not None:
stdout.write(
b"%s: %s\n"
% (h.encode('ascii'), response.getheader(h).encode('ascii'))
)
if headeronly:
# still read the body to prevent windows to be unhappy about that
# (this might some flakyness in test-hgweb-filelog.t on Windows)
data = response.read()
else:
stdout.write(b'\n')
data = response.read()
if args.bodyfile:
bodyfh = open(args.bodyfile, 'wb')
else:
bodyfh = stdout
# Pretty print JSON. This also has the beneficial side-effect
# of verifying emitted JSON is well-formed.
if formatjson:
# json.dumps() will print trailing newlines. Eliminate them
# to make tests easier to write.
data = pycompat.json_loads(data)
lines = json.dumps(data, sort_keys=True, indent=2).splitlines()
for line in lines:
bodyfh.write(pycompat.sysbytes(line.rstrip()))
bodyfh.write(b'\n')
else:
bodyfh.write(data)
if args.bodyfile:
bodyfh.close()
if twice and response.getheader('ETag', None):
tag = response.getheader('ETag')
# further try to please the windows-flakyness deity
conn.close()
return response.status
status = request(args.method, args.host, args.path, args.show)
if twice:
status = request(args.method, args.host, args.path, args.show)
if 200 <= status <= 305:
sys.exit(0)
sys.exit(1)