tests: make test-check-module-imports more robust It failed for me without this in this way: tests/test-commandserver.t:19: relative import of stdlib module tests/test-lfs-serve.t:108: relative import of stdlib module tests/test-lfs-serve.t:255: relative import of stdlib module tests/test-lfs-serve.t:362: relative import of stdlib module tests/test-lfs-serve.t:406: relative import of stdlib module tests/test-lock.py:9: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-lrucachedict.py:5: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-match.py:5: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-remotefilelog-datapack.py:15: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-remotefilelog-histpack.py:14: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-simplekeyvaluefile.py:4: imports not lexically sorted: silenttestrunner < unittest, True, True tests/test-sshserver.py:6: imports not lexically sorted: silenttestrunner < unittest, True, True This is because every module is considered a stdlib module, because the stdlib_prefixes is /usr, and my repo is in /usr/local/home, which means that sys.path contains a couple of /usr/local/home/../hg/.. entries that count as "in the stdlib". Fix this by preventing any path in sys.path that's inside the mercurial source from being considered "in the stdlib". Differential Revision: https://phab.mercurial-scm.org/D5294

#!/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()