view contrib/debugcmdserver.py @ 48737:a6efb9180764

sparse: rework debugsparse's interface

hg debugsparse supports arguments like --include, similar to `hg
tracked --addinclude` or `hg log --include`. But in `hg debugsparse`,
the pattern is not an argument of the flag, instead the patterns are
the anonymous command line arguments.

Not only is this surprising, it makes it impossible to use --include
and --exclude in the same invocation, or --reset --exclude.

So I propose making debugsparse making --include, --exclude take an
argument, and rejecting anonymous command line arguments, as well as
allowing mixing several of these flags in one invocations.

Differential Revision: https://phab.mercurial-scm.org/D12155

#!/usr/bin/env python3
#
# 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()