view contrib/debugcmdserver.py @ 32800:3e6f9bff7e3f

revset: filter first/last members by __and__ operation

This replaces 'if y in subset' with '& subset'. first(null) and last(wdir())
are fixed thanks to fullreposet.__and__.

This also revealed that first() and last() don't follow the order of the
input set. 'ls & subset' is valid only if the ordering requirement is 'define'
or 'any'.

No performance regression observed:

  revset #0: limit(0:9999, 100, 9000)
  0) 0.001164
  1) 0.001135
  revset #2: 9000 & limit(0:9999, 100, 9000)
  0) 0.001224
  1) 0.001181
  revset #3: last(0:9999, 100)
  0) 0.000237
  1) 0.000199

#!/usr/bin/env python
#
# Dumps output generated by Mercurial's command server in a formatted style to a
# given file or stderr if '-' is specified. Output is also written in its raw
# format to stdout.
#
# $ ./hg serve --cmds pipe | ./contrib/debugcmdserver.py -
# o, 52   -> 'capabilities: getencoding runcommand\nencoding: UTF-8'

from __future__ import absolute_import, print_function
import struct
import sys

if len(sys.argv) != 2:
    print('usage: debugcmdserver.py FILE')
    sys.exit(1)

outputfmt = '>cI'
outputfmtsize = struct.calcsize(outputfmt)

if sys.argv[1] == '-':
    log = sys.stderr
else:
    log = open(sys.argv[1], 'a')

def read(size):
    data = sys.stdin.read(size)
    if not data:
        raise EOFError
    sys.stdout.write(data)
    sys.stdout.flush()
    return data

try:
    while True:
        header = read(outputfmtsize)
        channel, length = struct.unpack(outputfmt, header)
        log.write('%s, %-4d' % (channel, length))
        if channel in 'IL':
            log.write(' -> waiting for input\n')
        else:
            data = read(length)
            log.write(' -> %r\n' % data)
        log.flush()
except EOFError:
    pass
finally:
    if log != sys.stderr:
        log.close()