docutils/frontend.py

   1 # $Id$
   2 # Author: David Goodger <goodger@python.org>
   3 # Copyright: This module has been placed in the public domain.
   4
   5 """
   6 Command-line and common processing for Docutils front-end tools.
   7
   8 Exports the following classes:
   9
  10 * `OptionParser`: Standard Docutils command-line processing.
  11 * `Option`: Customized version of `optparse.Option`; validation support.
  12 * `Values`: Runtime settings; objects are simple structs
  13   (``object.attribute``).  Supports cumulative list settings (attributes).
  14 * `ConfigParser`: Standard Docutils config file processing.
  15
  16 Also exports the following functions:
  17
  18 * Option callbacks: `store_multiple`, `read_config_file`.
  19 * Setting validators: `validate_encoding`,
  20   `validate_encoding_error_handler`,
  21   `validate_encoding_and_error_handler`,
  22   `validate_boolean`, `validate_ternary`, `validate_threshold`,
  23   `validate_colon_separated_string_list`,
  24   `validate_comma_separated_string_list`,
  25   `validate_dependency_file`.
  26 * `make_paths_absolute`.
  27 * SettingSpec manipulation: `filter_settings_spec`.
  28 """
  29
  30 __docformat__ = 'reStructuredText'
  31
  32 import os
  33 import os.path
  34 import sys
  35 import warnings
  36 import ConfigParser as CP
  37 import codecs
  38 import optparse
  39 from optparse import SUPPRESS_HELP
  40 import docutils
  41 import docutils.utils
  42 import docutils.nodes
  43 from docutils.utils.error_reporting import locale_encoding, ErrorOutput, ErrorString
  44
  45
  46 def store_multiple(option, opt, value, parser, *args, **kwargs):
  47     """
  48     Store multiple values in `parser.values`.  (Option callback.)
  49
  50     Store `None` for each attribute named in `args`, and store the value for
  51     each key (attribute name) in `kwargs`.
  52     """
  53     for attribute in args:
  54         setattr(parser.values, attribute, None)
  55     for key, value in kwargs.items():
  56         setattr(parser.values, key, value)
  57
  58 def read_config_file(option, opt, value, parser):
  59     """
  60     Read a configuration file during option processing.  (Option callback.)
  61     """
  62     try:
  63         new_settings = parser.get_config_file_settings(value)
  64     except ValueError, error:
  65         parser.error(error)
  66     parser.values.update(new_settings, parser)
  67
  68 def validate_encoding(setting, value, option_parser,
  69                       config_parser=None, config_section=None):
  70     try:
  71         codecs.lookup(value)
  72     except LookupError:
  73         raise (LookupError('setting "%s": unknown encoding: "%s"'
  74                            % (setting, value)),
  75                None, sys.exc_info()[2])
  76     return value
  77
  78 def validate_encoding_error_handler(setting, value, option_parser,
  79                                     config_parser=None, config_section=None):
  80     try:
  81         codecs.lookup_error(value)
  82     except LookupError:
  83         raise (LookupError(
  84             'unknown encoding error handler: "%s" (choices: '
  85             '"strict", "ignore", "replace", "backslashreplace", '
  86             '"xmlcharrefreplace", and possibly others; see documentation for '
  87             'the Python ``codecs`` module)' % value),
  88                None, sys.exc_info()[2])
  89     return value
  90
  91 def validate_encoding_and_error_handler(
  92     setting, value, option_parser, config_parser=None, config_section=None):
  93     """
  94     Side-effect: if an error handler is included in the value, it is inserted
  95     into the appropriate place as if it was a separate setting/option.
  96     """
  97     if ':' in value:
  98         encoding, handler = value.split(':')
  99         validate_encoding_error_handler(
 100             setting + '_error_handler', handler, option_parser,
 101             config_parser, config_section)
 102         if config_parser:
 103             config_parser.set(config_section, setting + '_error_handler',
 104                               handler)
 105         else:
 106             setattr(option_parser.values, setting + '_error_handler', handler)
 107     else:
 108         encoding = value
 109     validate_encoding(setting, encoding, option_parser,
 110                       config_parser, config_section)
 111     return encoding
 112
 113 def validate_boolean(setting, value, option_parser,
 114                      config_parser=None, config_section=None):
 115     """Check/normalize boolean settings:
 116          True:  '1', 'on', 'yes', 'true'
 117          False: '0', 'off', 'no','false', ''
 118     """
 119     if isinstance(value, bool):
 120         return value
 121     try:
 122         return option_parser.booleans[value.strip().lower()]
 123     except KeyError:
 124         raise (LookupError('unknown boolean value: "%s"' % value),
 125                None, sys.exc_info()[2])
 126
 127 def validate_ternary(setting, value, option_parser,
 128                      config_parser=None, config_section=None):
 129     """Check/normalize three-value settings:
 130          True:  '1', 'on', 'yes', 'true'
 131          False: '0', 'off', 'no','false',
 132          None:  any other value (including '')
 133     """
 134     if isinstance(value, bool) or value is None:
 135         return value
 136     if value == '':
 137         return None
 138     try:
 139         return option_parser.booleans[value.strip().lower()]
 140     except KeyError:
 141         return None
 142
 143 def validate_nonnegative_int(setting, value, option_parser,
 144                              config_parser=None, config_section=None):
 145     value = int(value)
 146     if value < 0:
 147         raise ValueError('negative value; must be positive or zero')
 148     return value
 149
 150 def validate_threshold(setting, value, option_parser,
 151                        config_parser=None, config_section=None):
 152     try:
 153         return int(value)
 154     except ValueError:
 155         try:
 156             return option_parser.thresholds[value.lower()]
 157         except (KeyError, AttributeError):
 158             raise (LookupError('unknown threshold: %r.' % value),
 159                    None, sys.exc_info[2])
 160
 161 def validate_colon_separated_string_list(
 162     setting, value, option_parser, config_parser=None, config_section=None):
 163     if isinstance(value, unicode):
 164         value = value.split(':')
 165     else:
 166         last = value.pop()
 167         value.extend(last.split(':'))
 168     return value
 169
 170 def validate_comma_separated_list(setting, value, option_parser,
 171                                     config_parser=None, config_section=None):
 172     """Check/normalize list arguments (split at "," and strip whitespace).
 173     """
 174     # `value` is already a list when  given as command line option
 175     # and "action" is "append"
 176     if isinstance(value, unicode):
 177         value = [value]
 178     # this function is called for every option added to `value`
 179     # -> split the last item and apped the result:
 180     last = value.pop()
 181     classes = [cls.strip(u' \t\n') for cls in last.split(',')
 182                if cls.strip(u' \t\n')]
 183     value.extend(classes)
 184     return value
 185
 186 def validate_url_trailing_slash(
 187     setting, value, option_parser, config_parser=None, config_section=None):
 188     if not value:
 189         return './'
 190     elif value.endswith('/'):
 191         return value
 192     else:
 193         return value + '/'
 194
 195 def validate_dependency_file(setting, value, option_parser,
 196                              config_parser=None, config_section=None):
 197     try:
 198         return docutils.utils.DependencyList(value)
 199     except IOError:
 200         return docutils.utils.DependencyList(None)
 201
 202 def validate_strip_class(setting, value, option_parser,
 203                          config_parser=None, config_section=None):
 204     # value is a comma separated string list:
 205     value = validate_comma_separated_list(setting, value, option_parser,
 206                                           config_parser, config_section)
 207     # validate list elements:
 208     for cls in value:
 209         normalized = docutils.nodes.make_id(cls)
 210         if cls != normalized:
 211             raise ValueError('invalid class value %r (perhaps %r?)'
 212                              % (cls, normalized))
 213     return value
 214
 215 def make_paths_absolute(pathdict, keys, base_path=None):
 216     """
 217     Interpret filesystem path settings relative to the `base_path` given.
 218
 219     Paths are values in `pathdict` whose keys are in `keys`.  Get `keys` from
 220     `OptionParser.relative_path_settings`.
 221     """
 222     if base_path is None:
 223         base_path = os.getcwdu() # type(base_path) == unicode
 224         # to allow combining non-ASCII cwd with unicode values in `pathdict`
 225     for key in keys:
 226         if key in pathdict:
 227             value = pathdict[key]
 228             if isinstance(value, list):
 229                 value = [make_one_path_absolute(base_path, path)
 230                          for path in value]
 231             elif value:
 232                 value = make_one_path_absolute(base_path, value)
 233             pathdict[key] = value
 234
 235 def make_one_path_absolute(base_path, path):
 236     return os.path.abspath(os.path.join(base_path, path))
 237
 238 def filter_settings_spec(settings_spec, *exclude, **replace):
 239     """Return a copy of `settings_spec` excluding/replacing some settings.
 240
 241     `settings_spec` is a tuple of configuration settings with a structure
 242     described for docutils.SettingsSpec.settings_spec.
 243
 244     Optional positional arguments are names of to-be-excluded settings.
 245     Keyword arguments are option specification replacements.
 246     (See the html4strict writer for an example.)
 247     """
 248     settings = list(settings_spec)
 249     # every third item is a sequence of option tuples
 250     for i in range(2, len(settings), 3):
 251         newopts = []
 252         for opt_spec in settings[i]:
 253             # opt_spec is ("<help>", [<option strings>], {<keyword args>})
 254             opt_name = [opt_string[2:].replace('-', '_')
 255                         for opt_string in opt_spec[1]
 256                             if opt_string.startswith('--')
 257                        ][0]
 258             if opt_name in exclude:
 259                 continue
 260             if opt_name in replace.keys():
 261                 newopts.append(replace[opt_name])
 262             else:
 263                 newopts.append(opt_spec)
 264         settings[i] = tuple(newopts)
 265     return tuple(settings)
 266
 267
 268 class Values(optparse.Values):
 269
 270     """
 271     Updates list attributes by extension rather than by replacement.
 272     Works in conjunction with the `OptionParser.lists` instance attribute.
 273     """
 274
 275     def __init__(self, *args, **kwargs):
 276         optparse.Values.__init__(self, *args, **kwargs)
 277         if (not hasattr(self, 'record_dependencies')
 278             or self.record_dependencies is None):
 279             # Set up dependency list, in case it is needed.
 280             self.record_dependencies = docutils.utils.DependencyList()
 281
 282     def update(self, other_dict, option_parser):
 283         if isinstance(other_dict, Values):
 284             other_dict = other_dict.__dict__
 285         other_dict = other_dict.copy()
 286         for setting in option_parser.lists.keys():
 287             if (hasattr(self, setting) and setting in other_dict):
 288                 value = getattr(self, setting)
 289                 if value:
 290                     value += other_dict[setting]
 291                     del other_dict[setting]
 292         self._update_loose(other_dict)
 293
 294     def copy(self):
 295         """Return a shallow copy of `self`."""
 296         return self.__class__(defaults=self.__dict__)
 297
 298
 299 class Option(optparse.Option):
 300
 301     ATTRS = optparse.Option.ATTRS + ['validator', 'overrides']
 302
 303     def process(self, opt, value, values, parser):
 304         """
 305         Call the validator function on applicable settings and
 306         evaluate the 'overrides' option.
 307         Extends `optparse.Option.process`.
 308         """
 309         result = optparse.Option.process(self, opt, value, values, parser)
 310         setting = self.dest
 311         if setting:
 312             if self.validator:
 313                 value = getattr(values, setting)
 314                 try:
 315                     new_value = self.validator(setting, value, parser)
 316                 except Exception, error:
 317                     raise (optparse.OptionValueError(
 318                         'Error in option "%s":\n    %s'
 319                         % (opt, ErrorString(error))),
 320                            None, sys.exc_info()[2])
 321                 setattr(values, setting, new_value)
 322             if self.overrides:
 323                 setattr(values, self.overrides, None)
 324         return result
 325
 326
 327 class OptionParser(optparse.OptionParser, docutils.SettingsSpec):
 328
 329     """
 330     Parser for command-line and library use.  The `settings_spec`
 331     specification here and in other Docutils components are merged to build
 332     the set of command-line options and runtime settings for this process.
 333
 334     Common settings (defined below) and component-specific settings must not
 335     conflict.  Short options are reserved for common settings, and components
 336     are restrict to using long options.
 337     """
 338
 339     standard_config_files = [
 340         '/etc/docutils.conf',           # system-wide
 341         './docutils.conf',              # project-specific
 342         '~/.docutils']                  # user-specific
 343     """Docutils configuration files, using ConfigParser syntax.  Filenames
 344     will be tilde-expanded later.  Later files override earlier ones."""
 345
 346     threshold_choices = 'info 1 warning 2 error 3 severe 4 none 5'.split()
 347     """Possible inputs for for --report and --halt threshold values."""
 348
 349     thresholds = {'info': 1, 'warning': 2, 'error': 3, 'severe': 4, 'none': 5}
 350     """Lookup table for --report and --halt threshold values."""
 351
 352     booleans={'1': 1, 'on': 1, 'yes': 1, 'true': 1,
 353               '0': 0, 'off': 0, 'no': 0, 'false': 0, '': 0}
 354     """Lookup table for boolean configuration file settings."""
 355
 356     default_error_encoding = getattr(sys.stderr, 'encoding',
 357                                      None) or locale_encoding or 'ascii'
 358
 359     default_error_encoding_error_handler = 'backslashreplace'
 360
 361     settings_spec = (
 362         'General Docutils Options',
 363         None,
 364         (('Specify the document title as metadata.',
 365           ['--title'], {}),
 366          ('Include a "Generated by Docutils" credit and link.',
 367           ['--generator', '-g'], {'action': 'store_true',
 368                                   'validator': validate_boolean}),
 369          ('Do not include a generator credit.',
 370           ['--no-generator'], {'action': 'store_false', 'dest': 'generator'}),
 371          ('Include the date at the end of the document (UTC).',
 372           ['--date', '-d'], {'action': 'store_const', 'const': '%Y-%m-%d',
 373                              'dest': 'datestamp'}),
 374          ('Include the time & date (UTC).',
 375           ['--time', '-t'], {'action': 'store_const',
 376                              'const': '%Y-%m-%d %H:%M UTC',
 377                              'dest': 'datestamp'}),
 378          ('Do not include a datestamp of any kind.',
 379           ['--no-datestamp'], {'action': 'store_const', 'const': None,
 380                                'dest': 'datestamp'}),
 381          ('Include a "View document source" link.',
 382           ['--source-link', '-s'], {'action': 'store_true',
 383                                     'validator': validate_boolean}),
 384          ('Use <URL> for a source link; implies --source-link.',
 385           ['--source-url'], {'metavar': '<URL>'}),
 386          ('Do not include a "View document source" link.',
 387           ['--no-source-link'],
 388           {'action': 'callback', 'callback': store_multiple,
 389            'callback_args': ('source_link', 'source_url')}),
 390          ('Link from section headers to TOC entries.  (default)',
 391           ['--toc-entry-backlinks'],
 392           {'dest': 'toc_backlinks', 'action': 'store_const', 'const': 'entry',
 393            'default': 'entry'}),
 394          ('Link from section headers to the top of the TOC.',
 395           ['--toc-top-backlinks'],
 396           {'dest': 'toc_backlinks', 'action': 'store_const', 'const': 'top'}),
 397          ('Disable backlinks to the table of contents.',
 398           ['--no-toc-backlinks'],
 399           {'dest': 'toc_backlinks', 'action': 'store_false'}),
 400          ('Link from footnotes/citations to references. (default)',
 401           ['--footnote-backlinks'],
 402           {'action': 'store_true', 'default': 1,
 403            'validator': validate_boolean}),
 404          ('Disable backlinks from footnotes and citations.',
 405           ['--no-footnote-backlinks'],
 406           {'dest': 'footnote_backlinks', 'action': 'store_false'}),
 407          ('Enable section numbering by Docutils.  (default)',
 408           ['--section-numbering'],
 409           {'action': 'store_true', 'dest': 'sectnum_xform',
 410            'default': 1, 'validator': validate_boolean}),
 411          ('Disable section numbering by Docutils.',
 412           ['--no-section-numbering'],
 413           {'action': 'store_false', 'dest': 'sectnum_xform'}),
 414          ('Remove comment elements from the document tree.',
 415           ['--strip-comments'],
 416           {'action': 'store_true', 'validator': validate_boolean}),
 417          ('Leave comment elements in the document tree. (default)',
 418           ['--leave-comments'],
 419           {'action': 'store_false', 'dest': 'strip_comments'}),
 420          ('Remove all elements with classes="<class>" from the document tree. '
 421           'Warning: potentially dangerous; use with caution. '
 422           '(Multiple-use option.)',
 423           ['--strip-elements-with-class'],
 424           {'action': 'append', 'dest': 'strip_elements_with_classes',
 425            'metavar': '<class>', 'validator': validate_strip_class}),
 426          ('Remove all classes="<class>" attributes from elements in the '
 427           'document tree. Warning: potentially dangerous; use with caution. '
 428           '(Multiple-use option.)',
 429           ['--strip-class'],
 430           {'action': 'append', 'dest': 'strip_classes',
 431            'metavar': '<class>', 'validator': validate_strip_class}),
 432          ('Report system messages at or higher than <level>: "info" or "1", '
 433           '"warning"/"2" (default), "error"/"3", "severe"/"4", "none"/"5"',
 434           ['--report', '-r'], {'choices': threshold_choices, 'default': 2,
 435                                'dest': 'report_level', 'metavar': '<level>',
 436                                'validator': validate_threshold}),
 437          ('Report all system messages.  (Same as "--report=1".)',
 438           ['--verbose', '-v'], {'action': 'store_const', 'const': 1,
 439                                 'dest': 'report_level'}),
 440          ('Report no system messages.  (Same as "--report=5".)',
 441           ['--quiet', '-q'], {'action': 'store_const', 'const': 5,
 442                               'dest': 'report_level'}),
 443          ('Halt execution at system messages at or above <level>.  '
 444           'Levels as in --report.  Default: 4 (severe).',
 445           ['--halt'], {'choices': threshold_choices, 'dest': 'halt_level',
 446                        'default': 4, 'metavar': '<level>',
 447                        'validator': validate_threshold}),
 448          ('Halt at the slightest problem.  Same as "--halt=info".',
 449           ['--strict'], {'action': 'store_const', 'const': 1,
 450                          'dest': 'halt_level'}),
 451          ('Enable a non-zero exit status for non-halting system messages at '
 452           'or above <level>.  Default: 5 (disabled).',
 453           ['--exit-status'], {'choices': threshold_choices,
 454                               'dest': 'exit_status_level',
 455                               'default': 5, 'metavar': '<level>',
 456                               'validator': validate_threshold}),
 457          ('Enable debug-level system messages and diagnostics.',
 458           ['--debug'], {'action': 'store_true', 'validator': validate_boolean}),
 459          ('Disable debug output.  (default)',
 460           ['--no-debug'], {'action': 'store_false', 'dest': 'debug'}),
 461          ('Send the output of system messages to <file>.',
 462           ['--warnings'], {'dest': 'warning_stream', 'metavar': '<file>'}),
 463          ('Enable Python tracebacks when Docutils is halted.',
 464           ['--traceback'], {'action': 'store_true', 'default': None,
 465                             'validator': validate_boolean}),
 466          ('Disable Python tracebacks.  (default)',
 467           ['--no-traceback'], {'dest': 'traceback', 'action': 'store_false'}),
 468          ('Specify the encoding and optionally the '
 469           'error handler of input text.  Default: <locale-dependent>:strict.',
 470           ['--input-encoding', '-i'],
 471           {'metavar': '<name[:handler]>',
 472            'validator': validate_encoding_and_error_handler}),
 473          ('Specify the error handler for undecodable characters.  '
 474           'Choices: "strict" (default), "ignore", and "replace".',
 475           ['--input-encoding-error-handler'],
 476           {'default': 'strict', 'validator': validate_encoding_error_handler}),
 477          ('Specify the text encoding and optionally the error handler for '
 478           'output.  Default: UTF-8:strict.',
 479           ['--output-encoding', '-o'],
 480           {'metavar': '<name[:handler]>', 'default': 'utf-8',
 481            'validator': validate_encoding_and_error_handler}),
 482          ('Specify error handler for unencodable output characters; '
 483           '"strict" (default), "ignore", "replace", '
 484           '"xmlcharrefreplace", "backslashreplace".',
 485           ['--output-encoding-error-handler'],
 486           {'default': 'strict', 'validator': validate_encoding_error_handler}),
 487          ('Specify text encoding and error handler for error output.  '
 488           'Default: %s:%s.'
 489           % (default_error_encoding, default_error_encoding_error_handler),
 490           ['--error-encoding', '-e'],
 491           {'metavar': '<name[:handler]>', 'default': default_error_encoding,
 492            'validator': validate_encoding_and_error_handler}),
 493          ('Specify the error handler for unencodable characters in '
 494           'error output.  Default: %s.'
 495           % default_error_encoding_error_handler,
 496           ['--error-encoding-error-handler'],
 497           {'default': default_error_encoding_error_handler,
 498            'validator': validate_encoding_error_handler}),
 499          ('Specify the language (as BCP 47 language tag).  Default: en.',
 500           ['--language', '-l'], {'dest': 'language_code', 'default': 'en',
 501                                  'metavar': '<name>'}),
 502          ('Write output file dependencies to <file>.',
 503           ['--record-dependencies'],
 504           {'metavar': '<file>', 'validator': validate_dependency_file,
 505            'default': None}),           # default set in Values class
 506          ('Read configuration settings from <file>, if it exists.',
 507           ['--config'], {'metavar': '<file>', 'type': 'string',
 508                          'action': 'callback', 'callback': read_config_file}),
 509          ("Show this program's version number and exit.",
 510           ['--version', '-V'], {'action': 'version'}),
 511          ('Show this help message and exit.',
 512           ['--help', '-h'], {'action': 'help'}),
 513          # Typically not useful for non-programmatical use:
 514          (SUPPRESS_HELP, ['--id-prefix'], {'default': ''}),
 515          (SUPPRESS_HELP, ['--auto-id-prefix'], {'default': 'id'}),
 516          # Hidden options, for development use only:
 517          (SUPPRESS_HELP, ['--dump-settings'], {'action': 'store_true'}),
 518          (SUPPRESS_HELP, ['--dump-internals'], {'action': 'store_true'}),
 519          (SUPPRESS_HELP, ['--dump-transforms'], {'action': 'store_true'}),
 520          (SUPPRESS_HELP, ['--dump-pseudo-xml'], {'action': 'store_true'}),
 521          (SUPPRESS_HELP, ['--expose-internal-attribute'],
 522           {'action': 'append', 'dest': 'expose_internals',
 523            'validator': validate_colon_separated_string_list}),
 524          (SUPPRESS_HELP, ['--strict-visitor'], {'action': 'store_true'}),
 525          ))
 526     """Runtime settings and command-line options common to all Docutils front
 527     ends.  Setting specs specific to individual Docutils components are also
 528     used (see `populate_from_components()`)."""
 529
 530     settings_defaults = {'_disable_config': None,
 531                          '_source': None,
 532                          '_destination': None,
 533                          '_config_files': None}
 534     """Defaults for settings that don't have command-line option equivalents."""
 535
 536     relative_path_settings = ('warning_stream',)
 537
 538     config_section = 'general'
 539
 540     version_template = ('%%prog (Docutils %s [%s], Python %s, on %s)'
 541                         % (docutils.__version__, docutils.__version_details__,
 542                            sys.version.split()[0], sys.platform))
 543     """Default version message."""
 544
 545     def __init__(self, components=(), defaults=None, read_config_files=None,
 546                  *args, **kwargs):
 547         """
 548         `components` is a list of Docutils components each containing a
 549         ``.settings_spec`` attribute.  `defaults` is a mapping of setting
 550         default overrides.
 551         """
 552
 553         self.lists = {}
 554         """Set of list-type settings."""
 555
 556         self.config_files = []
 557         """List of paths of applied configuration files."""
 558
 559         optparse.OptionParser.__init__(
 560             self, option_class=Option, add_help_option=None,
 561             formatter=optparse.TitledHelpFormatter(width=78),
 562             *args, **kwargs)
 563         if not self.version:
 564             self.version = self.version_template
 565         # Make an instance copy (it will be modified):
 566         self.relative_path_settings = list(self.relative_path_settings)
 567         self.components = (self,) + tuple(components)
 568         self.populate_from_components(self.components)
 569         self.set_defaults_from_dict(defaults or {})
 570         if read_config_files and not self.defaults['_disable_config']:
 571             try:
 572                 config_settings = self.get_standard_config_settings()
 573             except ValueError, error:
 574                 self.error(error)
 575             self.set_defaults_from_dict(config_settings.__dict__)
 576
 577     def populate_from_components(self, components):
 578         """
 579         For each component, first populate from the `SettingsSpec.settings_spec`
 580         structure, then from the `SettingsSpec.settings_defaults` dictionary.
 581         After all components have been processed, check for and populate from
 582         each component's `SettingsSpec.settings_default_overrides` dictionary.
 583         """
 584         for component in components:
 585             if component is None:
 586                 continue
 587             settings_spec = component.settings_spec
 588             self.relative_path_settings.extend(
 589                 component.relative_path_settings)
 590             for i in range(0, len(settings_spec), 3):
 591                 title, description, option_spec = settings_spec[i:i+3]
 592                 if title:
 593                     group = optparse.OptionGroup(self, title, description)
 594                     self.add_option_group(group)
 595                 else:
 596                     group = self        # single options
 597                 for (help_text, option_strings, kwargs) in option_spec:
 598                     option = group.add_option(help=help_text, *option_strings,
 599                                               **kwargs)
 600                     if kwargs.get('action') == 'append':
 601                         self.lists[option.dest] = 1
 602                 if component.settings_defaults:
 603                     self.defaults.update(component.settings_defaults)
 604         for component in components:
 605             if component and component.settings_default_overrides:
 606                 self.defaults.update(component.settings_default_overrides)
 607
 608     def get_standard_config_files(self):
 609         """Return list of config files, from environment or standard."""
 610         try:
 611             config_files = os.environ['DOCUTILSCONFIG'].split(os.pathsep)
 612         except KeyError:
 613             config_files = self.standard_config_files
 614
 615         # If 'HOME' is not set, expandvars() requires the 'pwd' module which is
 616         # not available under certain environments, for example, within
 617         # mod_python.  The publisher ends up in here, and we need to publish
 618         # from within mod_python.  Therefore we need to avoid expanding when we
 619         # are in those environments.
 620         expand = os.path.expanduser
 621         if 'HOME' not in os.environ:
 622             try:
 623                 import pwd
 624             except ImportError:
 625                 expand = lambda x: x
 626         return [expand(f) for f in config_files if f.strip()]
 627
 628     def get_standard_config_settings(self):
 629         settings = Values()
 630         for filename in self.get_standard_config_files():
 631             settings.update(self.get_config_file_settings(filename), self)
 632         return settings
 633
 634     def get_config_file_settings(self, config_file):
 635         """Returns a dictionary containing appropriate config file settings."""
 636         parser = ConfigParser()
 637         parser.read(config_file, self)
 638         self.config_files.extend(parser._files)
 639         base_path = os.path.dirname(config_file)
 640         applied = {}
 641         settings = Values()
 642         for component in self.components:
 643             if not component:
 644                 continue
 645             for section in (tuple(component.config_section_dependencies or ())
 646                             + (component.config_section,)):
 647                 if section in applied:
 648                     continue
 649                 applied[section] = 1
 650                 settings.update(parser.get_section(section), self)
 651         make_paths_absolute(
 652             settings.__dict__, self.relative_path_settings, base_path)
 653         return settings.__dict__
 654
 655     def check_values(self, values, args):
 656         """Store positional arguments as runtime settings."""
 657         values._source, values._destination = self.check_args(args)
 658         make_paths_absolute(values.__dict__, self.relative_path_settings)
 659         values._config_files = self.config_files
 660         return values
 661
 662     def check_args(self, args):
 663         source = destination = None
 664         if args:
 665             source = args.pop(0)
 666             if source == '-':           # means stdin
 667                 source = None
 668         if args:
 669             destination = args.pop(0)
 670             if destination == '-':      # means stdout
 671                 destination = None
 672         if args:
 673             self.error('Maximum 2 arguments allowed.')
 674         if source and source == destination:
 675             self.error('Do not specify the same file for both source and '
 676                        'destination.  It will clobber the source file.')
 677         return source, destination
 678
 679     def set_defaults_from_dict(self, defaults):
 680         self.defaults.update(defaults)
 681
 682     def get_default_values(self):
 683         """Needed to get custom `Values` instances."""
 684         defaults = Values(self.defaults)
 685         defaults._config_files = self.config_files
 686         return defaults
 687
 688     def get_option_by_dest(self, dest):
 689         """
 690         Get an option by its dest.
 691
 692         If you're supplying a dest which is shared by several options,
 693         it is undefined which option of those is returned.
 694
 695         A KeyError is raised if there is no option with the supplied
 696         dest.
 697         """
 698         for group in self.option_groups + [self]:
 699             for option in group.option_list:
 700                 if option.dest == dest:
 701                     return option
 702         raise KeyError('No option with dest == %r.' % dest)
 703
 704
 705 class ConfigParser(CP.RawConfigParser):
 706
 707     old_settings = {
 708         'pep_stylesheet': ('pep_html writer', 'stylesheet'),
 709         'pep_stylesheet_path': ('pep_html writer', 'stylesheet_path'),
 710         'pep_template': ('pep_html writer', 'template')}
 711     """{old setting: (new section, new setting)} mapping, used by
 712     `handle_old_config`, to convert settings from the old [options] section."""
 713
 714     old_warning = """
 715 The "[option]" section is deprecated.  Support for old-format configuration
 716 files may be removed in a future Docutils release.  Please revise your
 717 configuration files.  See <http://docutils.sf.net/docs/user/config.html>,
 718 section "Old-Format Configuration Files".
 719 """
 720
 721     not_utf8_error = """\
 722 Unable to read configuration file "%s": content not encoded as UTF-8.
 723 Skipping "%s" configuration file.
 724 """
 725
 726     def __init__(self, *args, **kwargs):
 727         CP.RawConfigParser.__init__(self, *args, **kwargs)
 728
 729         self._files = []
 730         """List of paths of configuration files read."""
 731
 732         self._stderr = ErrorOutput()
 733         """Wrapper around sys.stderr catching en-/decoding errors"""
 734
 735     def read(self, filenames, option_parser):
 736         if type(filenames) in (str, unicode):
 737             filenames = [filenames]
 738         for filename in filenames:
 739             try:
 740                 # Config files must be UTF-8-encoded:
 741                 fp = codecs.open(filename, 'r', 'utf-8')
 742             except IOError:
 743                 continue
 744             try:
 745                 if sys.version_info < (3,2):
 746                     CP.RawConfigParser.readfp(self, fp, filename)
 747                 else:
 748                     CP.RawConfigParser.read_file(self, fp, filename)
 749             except UnicodeDecodeError:
 750                 self._stderr.write(self.not_utf8_error % (filename, filename))
 751                 fp.close()
 752                 continue
 753             fp.close()
 754             self._files.append(filename)
 755             if self.has_section('options'):
 756                 self.handle_old_config(filename)
 757             self.validate_settings(filename, option_parser)
 758
 759     def handle_old_config(self, filename):
 760         warnings.warn_explicit(self.old_warning, ConfigDeprecationWarning,
 761                                filename, 0)
 762         options = self.get_section('options')
 763         if not self.has_section('general'):
 764             self.add_section('general')
 765         for key, value in options.items():
 766             if key in self.old_settings:
 767                 section, setting = self.old_settings[key]
 768                 if not self.has_section(section):
 769                     self.add_section(section)
 770             else:
 771                 section = 'general'
 772                 setting = key
 773             if not self.has_option(section, setting):
 774                 self.set(section, setting, value)
 775         self.remove_section('options')
 776
 777     def validate_settings(self, filename, option_parser):
 778         """
 779         Call the validator function and implement overrides on all applicable
 780         settings.
 781         """
 782         for section in self.sections():
 783             for setting in self.options(section):
 784                 try:
 785                     option = option_parser.get_option_by_dest(setting)
 786                 except KeyError:
 787                     continue
 788                 if option.validator:
 789                     value = self.get(section, setting)
 790                     try:
 791                         new_value = option.validator(
 792                             setting, value, option_parser,
 793                             config_parser=self, config_section=section)
 794                     except Exception, error:
 795                         raise (ValueError(
 796                             'Error in config file "%s", section "[%s]":\n'
 797                             '    %s\n'
 798                             '        %s = %s'
 799                             % (filename, section, ErrorString(error),
 800                                setting, value)), None, sys.exc_info()[2])
 801                     self.set(section, setting, new_value)
 802                 if option.overrides:
 803                     self.set(section, option.overrides, None)
 804
 805     def optionxform(self, optionstr):
 806         """
 807         Transform '-' to '_' so the cmdline form of option names can be used.
 808         """
 809         return optionstr.lower().replace('-', '_')
 810
 811     def get_section(self, section):
 812         """
 813         Return a given section as a dictionary (empty if the section
 814         doesn't exist).
 815         """
 816         section_dict = {}
 817         if self.has_section(section):
 818             for option in self.options(section):
 819                 section_dict[option] = self.get(section, option)
 820         return section_dict
 821
 822
 823 class ConfigDeprecationWarning(DeprecationWarning):
 824     """Warning for deprecated configuration file features."""