view mercurial/config.py @ 20197:761f2929a6ad

import-checker: refactor sys.path prefix check (issue4129)

This patch refactors the logic in contrib/import-checker.py responsible for
checking the beginnings of the paths in sys.path.  In particular, it adds a
variable that defines the set of allowed prefixes.

The primary purpose of this change is to make it easier to add more allowed
prefixes.  This will be useful in resolving issue4129, which involves making
the function list_stdlib_modules() work when run from a virtualenv.

# config.py - configuration parsing for Mercurial
#
#  Copyright 2009 Matt Mackall <[e-mail]> and others
#
# 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 error, util
import os, errno

class sortdict(dict):
    'a simple sorted dictionary'
    def __init__(self, data=None):
        self._list = []
        if data:
            self.update(data)
    def copy(self):
        return sortdict(self)
    def __setitem__(self, key, val):
        if key in self:
            self._list.remove(key)
        self._list.append(key)
        dict.__setitem__(self, key, val)
    def __iter__(self):
        return self._list.__iter__()
    def update(self, src):
        for k in src:
            self[k] = src[k]
    def clear(self):
        dict.clear(self)
        self._list = []
    def items(self):
        return [(k, self[k]) for k in self._list]
    def __delitem__(self, key):
        dict.__delitem__(self, key)
        self._list.remove(key)
    def keys(self):
        return self._list
    def iterkeys(self):
        return self._list.__iter__()

class config(object):
    def __init__(self, data=None):
        self._data = {}
        self._source = {}
        self._unset = []
        if data:
            for k in data._data:
                self._data[k] = data[k].copy()
            self._source = data._source.copy()
    def copy(self):
        return config(self)
    def __contains__(self, section):
        return section in self._data
    def __getitem__(self, section):
        return self._data.get(section, {})
    def __iter__(self):
        for d in self.sections():
            yield d
    def update(self, src):
        for s, n in src._unset:
            if s in self and n in self._data[s]:
                del self._data[s][n]
                del self._source[(s, n)]
        for s in src:
            if s not in self:
                self._data[s] = sortdict()
            self._data[s].update(src._data[s])
        self._source.update(src._source)
    def get(self, section, item, default=None):
        return self._data.get(section, {}).get(item, default)

    def backup(self, section, item):
        """return a tuple allowing restore to reinstall a previous value

        The main reason we need it is because it handles the "no data" case.
        """
        try:
            value = self._data[section][item]
            source = self.source(section, item)
            return (section, item, value, source)
        except KeyError:
            return (section, item)

    def source(self, section, item):
        return self._source.get((section, item), "")
    def sections(self):
        return sorted(self._data.keys())
    def items(self, section):
        return self._data.get(section, {}).items()
    def set(self, section, item, value, source=""):
        if section not in self:
            self._data[section] = sortdict()
        self._data[section][item] = value
        self._source[(section, item)] = source

    def restore(self, data):
        """restore data returned by self.backup"""
        if len(data) == 4:
            # restore old data
            section, item, value, source = data
            self._data[section][item] = value
            self._source[(section, item)] = source
        else:
            # no data before, remove everything
            section, item = data
            if section in self._data:
                del self._data[section][item]
            self._source.pop((section, item), None)

    def parse(self, src, data, sections=None, remap=None, include=None):
        sectionre = util.compilere(r'\[([^\[]+)\]')
        itemre = util.compilere(r'([^=\s][^=]*?)\s*=\s*(.*\S|)')
        contre = util.compilere(r'\s+(\S|\S.*\S)\s*$')
        emptyre = util.compilere(r'(;|#|\s*$)')
        commentre = util.compilere(r'(;|#)')
        unsetre = util.compilere(r'%unset\s+(\S+)')
        includere = util.compilere(r'%include\s+(\S|\S.*\S)\s*$')
        section = ""
        item = None
        line = 0
        cont = False

        for l in data.splitlines(True):
            line += 1
            if line == 1 and l.startswith('\xef\xbb\xbf'):
                # Someone set us up the BOM
                l = l[3:]
            if cont:
                if commentre.match(l):
                    continue
                m = contre.match(l)
                if m:
                    if sections and section not in sections:
                        continue
                    v = self.get(section, item) + "\n" + m.group(1)
                    self.set(section, item, v, "%s:%d" % (src, line))
                    continue
                item = None
                cont = False
            m = includere.match(l)
            if m:
                inc = util.expandpath(m.group(1))
                base = os.path.dirname(src)
                inc = os.path.normpath(os.path.join(base, inc))
                if include:
                    try:
                        include(inc, remap=remap, sections=sections)
                    except IOError, inst:
                        if inst.errno != errno.ENOENT:
                            raise error.ParseError(_("cannot include %s (%s)")
                                                   % (inc, inst.strerror),
                                                   "%s:%s" % (src, line))
                continue
            if emptyre.match(l):
                continue
            m = sectionre.match(l)
            if m:
                section = m.group(1)
                if remap:
                    section = remap.get(section, section)
                if section not in self:
                    self._data[section] = sortdict()
                continue
            m = itemre.match(l)
            if m:
                item = m.group(1)
                cont = True
                if sections and section not in sections:
                    continue
                self.set(section, item, m.group(2), "%s:%d" % (src, line))
                continue
            m = unsetre.match(l)
            if m:
                name = m.group(1)
                if sections and section not in sections:
                    continue
                if self.get(section, name) is not None:
                    del self._data[section][name]
                self._unset.append((section, name))
                continue

            raise error.ParseError(l.rstrip(), ("%s:%s" % (src, line)))

    def read(self, path, fp=None, sections=None, remap=None):
        if not fp:
            fp = util.posixfile(path)
        self.parse(path, fp.read(), sections, remap, self.read)