config: have a way to backup and restore value in config
This is introduce to allow temporary overwriting of a config value while being
able to reinstall the old value once done. The main advantage over using
``config`` and ``setconfig`` is that backup and restore will properly restore
the lack of any config. Restoring the fact that there was no value is important
to allow config user to keep using meaniful default value.
A more naive approach will result in the following scenario::
Before:
config(section, item, my_default) --> my_default
temporal overwrite
old = config(section, item)
…
setconfig(section, item, old)
After
config(section, item, my_default) --> None
The first user of this feature should be mq to overwriting minimal phase of
future commit.
# ignore.py - ignored file handling for mercurial
#
# Copyright 2007 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 i18n import _
import util, match
import re
_commentre = None
def ignorepats(lines):
'''parse lines (iterable) of .hgignore text, returning a tuple of
(patterns, parse errors). These patterns should be given to compile()
to be validated and converted into a match function.'''
syntaxes = {'re': 'relre:', 'regexp': 'relre:', 'glob': 'relglob:'}
syntax = 'relre:'
patterns = []
warnings = []
for line in lines:
if "#" in line:
global _commentre
if not _commentre:
_commentre = re.compile(r'((^|[^\\])(\\\\)*)#.*')
# remove comments prefixed by an even number of escapes
line = _commentre.sub(r'\1', line)
# fixup properly escaped comments that survived the above
line = line.replace("\\#", "#")
line = line.rstrip()
if not line:
continue
if line.startswith('syntax:'):
s = line[7:].strip()
try:
syntax = syntaxes[s]
except KeyError:
warnings.append(_("ignoring invalid syntax '%s'") % s)
continue
pat = syntax + line
for s, rels in syntaxes.iteritems():
if line.startswith(rels):
pat = line
break
elif line.startswith(s+':'):
pat = rels + line[len(s)+1:]
break
patterns.append(pat)
return patterns, warnings
def ignore(root, files, warn):
'''return matcher covering patterns in 'files'.
the files parsed for patterns include:
.hgignore in the repository root
any additional files specified in the [ui] section of ~/.hgrc
trailing white space is dropped.
the escape character is backslash.
comments start with #.
empty lines are skipped.
lines can be of the following formats:
syntax: regexp # defaults following lines to non-rooted regexps
syntax: glob # defaults following lines to non-rooted globs
re:pattern # non-rooted regular expression
glob:pattern # non-rooted glob
pattern # pattern of the current default type'''
pats = {}
for f in files:
try:
pats[f] = []
fp = open(f)
pats[f], warnings = ignorepats(fp)
fp.close()
for warning in warnings:
warn("%s: %s\n" % (f, warning))
except IOError, inst:
if f != files[0]:
warn(_("skipping unreadable ignore file '%s': %s\n") %
(f, inst.strerror))
allpats = []
for patlist in pats.values():
allpats.extend(patlist)
if not allpats:
return util.never
try:
ignorefunc = match.match(root, '', [], allpats)
except util.Abort:
# Re-raise an exception where the src is the right file
for f, patlist in pats.iteritems():
try:
match.match(root, '', [], patlist)
except util.Abort, inst:
raise util.Abort('%s: %s' % (f, inst[0]))
return ignorefunc