##// END OF EJS Templates
posix: always seek to EOF when opening a file in append mode...
posix: always seek to EOF when opening a file in append mode Python 3 already does this, so skip it there. Consider the program: #include <stdio.h> int main() { FILE *f = fopen("narf", "w"); fprintf(f, "narf\n"); fclose(f); f = fopen("narf", "a"); printf("%ld\n", ftell(f)); fprintf(f, "troz\n"); printf("%ld\n", ftell(f)); return 0; } on macOS, FreeBSD, and Linux with glibc, this program prints 5 10 but on musl libc (Alpine Linux and probably others) this prints 0 10 By my reading of https://pubs.opengroup.org/onlinepubs/009695399/functions/fopen.html this is technically correct, specifically: > Opening a file with append mode (a as the first character in the > mode argument) shall cause all subsequent writes to the file to be > forced to the then current end-of-file, regardless of intervening > calls to fseek(). in other words, the file position doesn't really matter in append-mode files, and we can't depend on it being at all meaningful unless we perform a seek() before tell() after open(..., 'a'). Experimentally after a .write() we can do a .tell() and it'll always be reasonable, but I'm unclear from reading the specification if that's a smart thing to rely on. This matches what we do on Windows and what Python 3 does for free, so let's just be consistent. Thanks to Yuya for the idea.

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r41682:595a67a3 default
r42778:97ada9b8 5.0.2 stable
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check-config.py
159 lines | 5.1 KiB | text/x-python | PythonLexer
#!/usr/bin/env python
#
# check-config - a config flag documentation checker for Mercurial
#
# Copyright 2015 Matt Mackall <mpm@selenic.com>
#
# 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]))