view contrib/check-config.py @ 45095:8e04607023e5

procutil: ensure that procutil.std{out,err}.write() writes all bytes

Python 3 offers different kind of streams and it’s not guaranteed for all of
them that calling write() writes all bytes.

When Python is started in unbuffered mode, sys.std{out,err}.buffer are
instances of io.FileIO, whose write() can write less bytes for
platform-specific reasons (e.g. Linux has a 0x7ffff000 bytes maximum and could
write less if interrupted by a signal; when writing to Windows consoles, it’s
limited to 32767 bytes to avoid the "not enough space" error). This can lead to
silent loss of data, both when using sys.std{out,err}.buffer (which may in fact
not be a buffered stream) and when using the text streams sys.std{out,err}
(I’ve created a CPython bug report for that:
https://bugs.python.org/issue41221).

Python may fix the problem at some point. For now, we implement our own wrapper
for procutil.std{out,err} that calls the raw stream’s write() method until all
bytes have been written. We don’t use sys.std{out,err} for larger writes, so I
think it’s not worth the effort to patch them.

#!/usr/bin/env python
#
# check-config - a config flag documentation checker for Mercurial
#
# Copyright 2015 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import, print_function
import re
import sys

foundopts = {}
documented = {}
allowinconsistent = set()

configre = re.compile(
    br'''
    # Function call
    ui\.config(?P<ctype>|int|bool|list)\(
        # First argument.
        ['"](?P<section>\S+)['"],\s*
        # Second argument
        ['"](?P<option>\S+)['"](,\s+
        (?:default=)?(?P<default>\S+?))?
    \)''',
    re.VERBOSE | re.MULTILINE,
)

configwithre = re.compile(
    br'''
    ui\.config(?P<ctype>with)\(
        # First argument is callback function. This doesn't parse robustly
        # if it is e.g. a function call.
        [^,]+,\s*
        ['"](?P<section>\S+)['"],\s*
        ['"](?P<option>\S+)['"](,\s+
        (?:default=)?(?P<default>\S+?))?
    \)''',
    re.VERBOSE | re.MULTILINE,
)

configpartialre = br"""ui\.config"""

ignorere = re.compile(
    br'''
    \#\s(?P<reason>internal|experimental|deprecated|developer|inconsistent)\s
    config:\s(?P<config>\S+\.\S+)$
    ''',
    re.VERBOSE | re.MULTILINE,
)

if sys.version_info[0] > 2:

    def mkstr(b):
        if isinstance(b, str):
            return b
        return b.decode('utf8')


else:
    mkstr = lambda x: x


def main(args):
    for f in args:
        sect = b''
        prevname = b''
        confsect = b''
        carryover = b''
        linenum = 0
        for l in open(f, 'rb'):
            linenum += 1

            # check topic-like bits
            m = re.match(br'\s*``(\S+)``', l)
            if m:
                prevname = m.group(1)
            if re.match(br'^\s*-+$', l):
                sect = prevname
                prevname = b''

            if sect and prevname:
                name = sect + b'.' + prevname
                documented[name] = 1

            # check docstring bits
            m = re.match(br'^\s+\[(\S+)\]', l)
            if m:
                confsect = m.group(1)
                continue
            m = re.match(br'^\s+(?:#\s*)?(\S+) = ', l)
            if m:
                name = confsect + b'.' + m.group(1)
                documented[name] = 1

            # like the bugzilla extension
            m = re.match(br'^\s*(\S+\.\S+)$', l)
            if m:
                documented[m.group(1)] = 1

            # like convert
            m = re.match(br'^\s*:(\S+\.\S+):\s+', l)
            if m:
                documented[m.group(1)] = 1

            # quoted in help or docstrings
            m = re.match(br'.*?``(\S+\.\S+)``', l)
            if m:
                documented[m.group(1)] = 1

            # look for ignore markers
            m = ignorere.search(l)
            if m:
                if m.group('reason') == b'inconsistent':
                    allowinconsistent.add(m.group('config'))
                else:
                    documented[m.group('config')] = 1

            # look for code-like bits
            line = carryover + l
            m = configre.search(line) or configwithre.search(line)
            if m:
                ctype = m.group('ctype')
                if not ctype:
                    ctype = 'str'
                name = m.group('section') + b"." + m.group('option')
                default = m.group('default')
                if default in (
                    None,
                    b'False',
                    b'None',
                    b'0',
                    b'[]',
                    b'""',
                    b"''",
                ):
                    default = b''
                if re.match(b'[a-z.]+$', default):
                    default = b'<variable>'
                if (
                    name in foundopts
                    and (ctype, default) != foundopts[name]
                    and name not in allowinconsistent
                ):
                    print(mkstr(l.rstrip()))
                    fctype, fdefault = foundopts[name]
                    print(
                        "conflict on %s: %r != %r"
                        % (
                            mkstr(name),
                            (mkstr(ctype), mkstr(default)),
                            (mkstr(fctype), mkstr(fdefault)),
                        )
                    )
                    print("at %s:%d:" % (mkstr(f), linenum))
                foundopts[name] = (ctype, default)
                carryover = b''
            else:
                m = re.search(configpartialre, line)
                if m:
                    carryover = line
                else:
                    carryover = b''

    for name in sorted(foundopts):
        if name not in documented:
            if not (
                name.startswith(b"devel.")
                or name.startswith(b"experimental.")
                or name.startswith(b"debug.")
            ):
                ctype, default = foundopts[name]
                if default:
                    if isinstance(default, bytes):
                        default = mkstr(default)
                    default = ' [%s]' % default
                elif isinstance(default, bytes):
                    default = mkstr(default)
                print(
                    "undocumented: %s (%s)%s"
                    % (mkstr(name), mkstr(ctype), default)
                )


if __name__ == "__main__":
    if len(sys.argv) > 1:
        sys.exit(main(sys.argv[1:]))
    else:
        sys.exit(main([l.rstrip() for l in sys.stdin]))