182 

   183 def parselist(value):

   184     """parse a configuration value as a list of comma/space separated strings

   185 

   186     >>> parselist('this,is "a small" ,test')

   187     ['this', 'is', 'a small', 'test']

   188     """

   189 

   190     def _parse_plain(parts, s, offset):

   191         whitespace = False

   192         while offset < len(s) and (s[offset:offset + 1].isspace()

   193                                    or s[offset:offset + 1] == ','):

   194             whitespace = True

   195             offset += 1

   196         if offset >= len(s):

   197             return None, parts, offset

   198         if whitespace:

   199             parts.append('')

   200         if s[offset:offset + 1] == '"' and not parts[-1]:

   201             return _parse_quote, parts, offset + 1

   202         elif s[offset:offset + 1] == '"' and parts[-1][-1] == '\\':

   203             parts[-1] = parts[-1][:-1] + s[offset:offset + 1]

   204             return _parse_plain, parts, offset + 1

   205         parts[-1] += s[offset:offset + 1]

   206         return _parse_plain, parts, offset + 1

   207 

   208     def _parse_quote(parts, s, offset):

   209         if offset < len(s) and s[offset:offset + 1] == '"': # ""

   210             parts.append('')

   211             offset += 1

   212             while offset < len(s) and (s[offset:offset + 1].isspace() or

   213                     s[offset:offset + 1] == ','):

   214                 offset += 1

   215             return _parse_plain, parts, offset

   216 

   217         while offset < len(s) and s[offset:offset + 1] != '"':

   218             if (s[offset:offset + 1] == '\\' and offset + 1 < len(s)

   219                     and s[offset + 1:offset + 2] == '"'):

   220                 offset += 1

   221                 parts[-1] += '"'

   222             else:

   223                 parts[-1] += s[offset:offset + 1]

   224             offset += 1

   225 

   226         if offset >= len(s):

   227             real_parts = _configlist(parts[-1])

   228             if not real_parts:

   229                 parts[-1] = '"'

   230             else:

   231                 real_parts[0] = '"' + real_parts[0]

   232                 parts = parts[:-1]

   233                 parts.extend(real_parts)

   234             return None, parts, offset

   235 

   236         offset += 1

   237         while offset < len(s) and s[offset:offset + 1] in [' ', ',']:

   238             offset += 1

   239 

   240         if offset < len(s):

   241             if offset + 1 == len(s) and s[offset:offset + 1] == '"':

   242                 parts[-1] += '"'

   243                 offset += 1

   244             else:

   245                 parts.append('')

   246         else:

   247             return None, parts, offset

   248 

   249         return _parse_plain, parts, offset

   250 

   251     def _configlist(s):

   252         s = s.rstrip(' ,')

   253         if not s:

   254             return []

   255         parser, parts, offset = _parse_plain, [''], 0

   256         while parser:

   257             parser, parts, offset = parser(parts, s, offset)

   258         return parts

   259 

   260     if value is not None and isinstance(value, bytes):

   261         result = _configlist(value.lstrip(' ,\n'))

   262     else:

   263         result = value

   264     return result or []