--- a/env/lib/python3.7/site-packages/docutils/frontend.py	Thu May 14 16:47:39 2020 -0400
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,863 +0,0 @@
-# $Id: frontend.py 8439 2019-12-13 17:02:41Z milde $
-# Author: David Goodger <goodger@python.org>
-# Copyright: This module has been placed in the public domain.
-
-"""
-Command-line and common processing for Docutils front-end tools.
-
-Exports the following classes:
-
-* `OptionParser`: Standard Docutils command-line processing.
-* `Option`: Customized version of `optparse.Option`; validation support.
-* `Values`: Runtime settings; objects are simple structs
-  (``object.attribute``).  Supports cumulative list settings (attributes).
-* `ConfigParser`: Standard Docutils config file processing.
-
-Also exports the following functions:
-
-* Option callbacks: `store_multiple`, `read_config_file`.
-* Setting validators: `validate_encoding`,
-  `validate_encoding_error_handler`,
-  `validate_encoding_and_error_handler`,
-  `validate_boolean`, `validate_ternary`, `validate_threshold`,
-  `validate_colon_separated_string_list`,
-  `validate_comma_separated_string_list`,
-  `validate_dependency_file`.
-* `make_paths_absolute`.
-* SettingSpec manipulation: `filter_settings_spec`.
-"""
-
-__docformat__ = 'reStructuredText'
-
-import os
-import os.path
-import sys
-import warnings
-import codecs
-import optparse
-from optparse import SUPPRESS_HELP
-if sys.version_info >= (3, 0):
-    from configparser import RawConfigParser
-    from os import getcwd
-else:
-    from ConfigParser import RawConfigParser
-    from os import getcwdu as getcwd
-
-import docutils
-import docutils.utils
-import docutils.nodes
-from docutils.utils.error_reporting import (locale_encoding, SafeString,
-                                            ErrorOutput, ErrorString)
-
-if sys.version_info >= (3, 0):
-    unicode = str  # noqa
-
-
-def store_multiple(option, opt, value, parser, *args, **kwargs):
-    """
-    Store multiple values in `parser.values`.  (Option callback.)
-
-    Store `None` for each attribute named in `args`, and store the value for
-    each key (attribute name) in `kwargs`.
-    """
-    for attribute in args:
-        setattr(parser.values, attribute, None)
-    for key, value in kwargs.items():
-        setattr(parser.values, key, value)
-
-def read_config_file(option, opt, value, parser):
-    """
-    Read a configuration file during option processing.  (Option callback.)
-    """
-    try:
-        new_settings = parser.get_config_file_settings(value)
-    except ValueError as error:
-        parser.error(error)
-    parser.values.update(new_settings, parser)
-
-def validate_encoding(setting, value, option_parser,
-                      config_parser=None, config_section=None):
-    try:
-        codecs.lookup(value)
-    except LookupError:
-        raise LookupError('setting "%s": unknown encoding: "%s"'
-                          % (setting, value))
-    return value
-
-def validate_encoding_error_handler(setting, value, option_parser,
-                                    config_parser=None, config_section=None):
-    try:
-        codecs.lookup_error(value)
-    except LookupError:
-        raise LookupError(
-            'unknown encoding error handler: "%s" (choices: '
-            '"strict", "ignore", "replace", "backslashreplace", '
-            '"xmlcharrefreplace", and possibly others; see documentation for '
-            'the Python ``codecs`` module)' % value)
-    return value
-
-def validate_encoding_and_error_handler(
-    setting, value, option_parser, config_parser=None, config_section=None):
-    """
-    Side-effect: if an error handler is included in the value, it is inserted
-    into the appropriate place as if it was a separate setting/option.
-    """
-    if ':' in value:
-        encoding, handler = value.split(':')
-        validate_encoding_error_handler(
-            setting + '_error_handler', handler, option_parser,
-            config_parser, config_section)
-        if config_parser:
-            config_parser.set(config_section, setting + '_error_handler',
-                              handler)
-        else:
-            setattr(option_parser.values, setting + '_error_handler', handler)
-    else:
-        encoding = value
-    validate_encoding(setting, encoding, option_parser,
-                      config_parser, config_section)
-    return encoding
-
-def validate_boolean(setting, value, option_parser,
-                     config_parser=None, config_section=None):
-    """Check/normalize boolean settings:
-         True:  '1', 'on', 'yes', 'true'
-         False: '0', 'off', 'no','false', ''
-    """
-    if isinstance(value, bool):
-        return value
-    try:
-        return option_parser.booleans[value.strip().lower()]
-    except KeyError:
-        raise LookupError('unknown boolean value: "%s"' % value)
-
-def validate_ternary(setting, value, option_parser,
-                     config_parser=None, config_section=None):
-    """Check/normalize three-value settings:
-         True:  '1', 'on', 'yes', 'true'
-         False: '0', 'off', 'no','false', ''
-         any other value: returned as-is.
-    """
-    if isinstance(value, bool) or value is None:
-        return value
-    try:
-        return option_parser.booleans[value.strip().lower()]
-    except KeyError:
-        return value
-
-def validate_nonnegative_int(setting, value, option_parser,
-                             config_parser=None, config_section=None):
-    value = int(value)
-    if value < 0:
-        raise ValueError('negative value; must be positive or zero')
-    return value
-
-def validate_threshold(setting, value, option_parser,
-                       config_parser=None, config_section=None):
-    try:
-        return int(value)
-    except ValueError:
-        try:
-            return option_parser.thresholds[value.lower()]
-        except (KeyError, AttributeError):
-            raise LookupError('unknown threshold: %r.' % value)
-
-def validate_colon_separated_string_list(
-    setting, value, option_parser, config_parser=None, config_section=None):
-    if not isinstance(value, list):
-        value = value.split(':')
-    else:
-        last = value.pop()
-        value.extend(last.split(':'))
-    return value
-
-def validate_comma_separated_list(setting, value, option_parser,
-                                    config_parser=None, config_section=None):
-    """Check/normalize list arguments (split at "," and strip whitespace).
-    """
-    # `value` is already a ``list`` when  given as command line option
-    # and "action" is "append" and ``unicode`` or ``str`` else.
-    if not isinstance(value, list):
-        value = [value]
-    # this function is called for every option added to `value`
-    # -> split the last item and append the result:
-    last = value.pop()
-    items = [i.strip(u' \t\n') for i in last.split(u',') if i.strip(u' \t\n')]
-    value.extend(items)
-    return value
-
-def validate_url_trailing_slash(
-    setting, value, option_parser, config_parser=None, config_section=None):
-    if not value:
-        return './'
-    elif value.endswith('/'):
-        return value
-    else:
-        return value + '/'
-
-def validate_dependency_file(setting, value, option_parser,
-                             config_parser=None, config_section=None):
-    try:
-        return docutils.utils.DependencyList(value)
-    except IOError:
-        return docutils.utils.DependencyList(None)
-
-def validate_strip_class(setting, value, option_parser,
-                         config_parser=None, config_section=None):
-    # value is a comma separated string list:
-    value = validate_comma_separated_list(setting, value, option_parser,
-                                          config_parser, config_section)
-    # validate list elements:
-    for cls in value:
-        normalized = docutils.nodes.make_id(cls)
-        if cls != normalized:
-            raise ValueError('Invalid class value %r (perhaps %r?)'
-                             % (cls, normalized))
-    return value
-
-def validate_smartquotes_locales(setting, value, option_parser,
-                         config_parser=None, config_section=None):
-    """Check/normalize a comma separated list of smart quote definitions.
-
-    Return a list of (language-tag, quotes) string tuples."""
-
-    # value is a comma separated string list:
-    value = validate_comma_separated_list(setting, value, option_parser,
-                                          config_parser, config_section)
-    # validate list elements
-    lc_quotes = []
-    for item in value:
-        try:
-            lang, quotes = item.split(':', 1)
-        except AttributeError:
-            # this function is called for every option added to `value`
-            # -> ignore if already a tuple:
-            lc_quotes.append(item)
-            continue
-        except ValueError:
-            raise ValueError(u'Invalid value "%s".'
-                             ' Format is "<language>:<quotes>".'
-                             % item.encode('ascii', 'backslashreplace'))
-        # parse colon separated string list:
-        quotes = quotes.strip()
-        multichar_quotes = quotes.split(':')
-        if len(multichar_quotes) == 4:
-            quotes = multichar_quotes
-        elif len(quotes) != 4:
-            raise ValueError('Invalid value "%s". Please specify 4 quotes\n'
-                '    (primary open/close; secondary open/close).'
-                             % item.encode('ascii', 'backslashreplace'))
-        lc_quotes.append((lang, quotes))
-    return lc_quotes
-
-def make_paths_absolute(pathdict, keys, base_path=None):
-    """
-    Interpret filesystem path settings relative to the `base_path` given.
-
-    Paths are values in `pathdict` whose keys are in `keys`.  Get `keys` from
-    `OptionParser.relative_path_settings`.
-    """
-    if base_path is None:
-        base_path = getcwd() # type(base_path) == unicode
-        # to allow combining non-ASCII cwd with unicode values in `pathdict`
-    for key in keys:
-        if key in pathdict:
-            value = pathdict[key]
-            if isinstance(value, list):
-                value = [make_one_path_absolute(base_path, path)
-                         for path in value]
-            elif value:
-                value = make_one_path_absolute(base_path, value)
-            pathdict[key] = value
-
-def make_one_path_absolute(base_path, path):
-    return os.path.abspath(os.path.join(base_path, path))
-
-def filter_settings_spec(settings_spec, *exclude, **replace):
-    """Return a copy of `settings_spec` excluding/replacing some settings.
-
-    `settings_spec` is a tuple of configuration settings with a structure
-    described for docutils.SettingsSpec.settings_spec.
-
-    Optional positional arguments are names of to-be-excluded settings.
-    Keyword arguments are option specification replacements.
-    (See the html4strict writer for an example.)
-    """
-    settings = list(settings_spec)
-    # every third item is a sequence of option tuples
-    for i in range(2, len(settings), 3):
-        newopts = []
-        for opt_spec in settings[i]:
-            # opt_spec is ("<help>", [<option strings>], {<keyword args>})
-            opt_name = [opt_string[2:].replace('-', '_')
-                        for opt_string in opt_spec[1]
-                            if opt_string.startswith('--')
-                       ][0]
-            if opt_name in exclude:
-                continue
-            if opt_name in replace.keys():
-                newopts.append(replace[opt_name])
-            else:
-                newopts.append(opt_spec)
-        settings[i] = tuple(newopts)
-    return tuple(settings)
-
-
-class Values(optparse.Values):
-
-    """
-    Updates list attributes by extension rather than by replacement.
-    Works in conjunction with the `OptionParser.lists` instance attribute.
-    """
-
-    def __init__(self, *args, **kwargs):
-        optparse.Values.__init__(self, *args, **kwargs)
-        if (not hasattr(self, 'record_dependencies')
-            or self.record_dependencies is None):
-            # Set up dependency list, in case it is needed.
-            self.record_dependencies = docutils.utils.DependencyList()
-
-    def update(self, other_dict, option_parser):
-        if isinstance(other_dict, Values):
-            other_dict = other_dict.__dict__
-        other_dict = other_dict.copy()
-        for setting in option_parser.lists.keys():
-            if (hasattr(self, setting) and setting in other_dict):
-                value = getattr(self, setting)
-                if value:
-                    value += other_dict[setting]
-                    del other_dict[setting]
-        self._update_loose(other_dict)
-
-    def copy(self):
-        """Return a shallow copy of `self`."""
-        return self.__class__(defaults=self.__dict__)
-
-
-class Option(optparse.Option):
-
-    ATTRS = optparse.Option.ATTRS + ['validator', 'overrides']
-
-    def process(self, opt, value, values, parser):
-        """
-        Call the validator function on applicable settings and
-        evaluate the 'overrides' option.
-        Extends `optparse.Option.process`.
-        """
-        result = optparse.Option.process(self, opt, value, values, parser)
-        setting = self.dest
-        if setting:
-            if self.validator:
-                value = getattr(values, setting)
-                try:
-                    new_value = self.validator(setting, value, parser)
-                except Exception as error:
-                    raise optparse.OptionValueError(
-                        'Error in option "%s":\n    %s'
-                        % (opt, ErrorString(error)))
-                setattr(values, setting, new_value)
-            if self.overrides:
-                setattr(values, self.overrides, None)
-        return result
-
-
-class OptionParser(optparse.OptionParser, docutils.SettingsSpec):
-
-    """
-    Parser for command-line and library use.  The `settings_spec`
-    specification here and in other Docutils components are merged to build
-    the set of command-line options and runtime settings for this process.
-
-    Common settings (defined below) and component-specific settings must not
-    conflict.  Short options are reserved for common settings, and components
-    are restrict to using long options.
-    """
-
-    standard_config_files = [
-        '/etc/docutils.conf',           # system-wide
-        './docutils.conf',              # project-specific
-        '~/.docutils']                  # user-specific
-    """Docutils configuration files, using ConfigParser syntax.  Filenames
-    will be tilde-expanded later.  Later files override earlier ones."""
-
-    threshold_choices = 'info 1 warning 2 error 3 severe 4 none 5'.split()
-    """Possible inputs for for --report and --halt threshold values."""
-
-    thresholds = {'info': 1, 'warning': 2, 'error': 3, 'severe': 4, 'none': 5}
-    """Lookup table for --report and --halt threshold values."""
-
-    booleans={'1': True, 'on': True, 'yes': True, 'true': True,
-              '0': False, 'off': False, 'no': False, 'false': False, '': False}
-    """Lookup table for boolean configuration file settings."""
-
-    default_error_encoding = getattr(sys.stderr, 'encoding',
-                                     None) or locale_encoding or 'ascii'
-
-    default_error_encoding_error_handler = 'backslashreplace'
-
-    settings_spec = (
-        'General Docutils Options',
-        None,
-        (('Specify the document title as metadata.',
-          ['--title'], {}),
-         ('Include a "Generated by Docutils" credit and link.',
-          ['--generator', '-g'], {'action': 'store_true',
-                                  'validator': validate_boolean}),
-         ('Do not include a generator credit.',
-          ['--no-generator'], {'action': 'store_false', 'dest': 'generator'}),
-         ('Include the date at the end of the document (UTC).',
-          ['--date', '-d'], {'action': 'store_const', 'const': '%Y-%m-%d',
-                             'dest': 'datestamp'}),
-         ('Include the time & date (UTC).',
-          ['--time', '-t'], {'action': 'store_const',
-                             'const': '%Y-%m-%d %H:%M UTC',
-                             'dest': 'datestamp'}),
-         ('Do not include a datestamp of any kind.',
-          ['--no-datestamp'], {'action': 'store_const', 'const': None,
-                               'dest': 'datestamp'}),
-         ('Include a "View document source" link.',
-          ['--source-link', '-s'], {'action': 'store_true',
-                                    'validator': validate_boolean}),
-         ('Use <URL> for a source link; implies --source-link.',
-          ['--source-url'], {'metavar': '<URL>'}),
-         ('Do not include a "View document source" link.',
-          ['--no-source-link'],
-          {'action': 'callback', 'callback': store_multiple,
-           'callback_args': ('source_link', 'source_url')}),
-         ('Link from section headers to TOC entries.  (default)',
-          ['--toc-entry-backlinks'],
-          {'dest': 'toc_backlinks', 'action': 'store_const', 'const': 'entry',
-           'default': 'entry'}),
-         ('Link from section headers to the top of the TOC.',
-          ['--toc-top-backlinks'],
-          {'dest': 'toc_backlinks', 'action': 'store_const', 'const': 'top'}),
-         ('Disable backlinks to the table of contents.',
-          ['--no-toc-backlinks'],
-          {'dest': 'toc_backlinks', 'action': 'store_false'}),
-         ('Link from footnotes/citations to references. (default)',
-          ['--footnote-backlinks'],
-          {'action': 'store_true', 'default': 1,
-           'validator': validate_boolean}),
-         ('Disable backlinks from footnotes and citations.',
-          ['--no-footnote-backlinks'],
-          {'dest': 'footnote_backlinks', 'action': 'store_false'}),
-         ('Enable section numbering by Docutils.  (default)',
-          ['--section-numbering'],
-          {'action': 'store_true', 'dest': 'sectnum_xform',
-           'default': 1, 'validator': validate_boolean}),
-         ('Disable section numbering by Docutils.',
-          ['--no-section-numbering'],
-          {'action': 'store_false', 'dest': 'sectnum_xform'}),
-         ('Remove comment elements from the document tree.',
-          ['--strip-comments'],
-          {'action': 'store_true', 'validator': validate_boolean}),
-         ('Leave comment elements in the document tree. (default)',
-          ['--leave-comments'],
-          {'action': 'store_false', 'dest': 'strip_comments'}),
-         ('Remove all elements with classes="<class>" from the document tree. '
-          'Warning: potentially dangerous; use with caution. '
-          '(Multiple-use option.)',
-          ['--strip-elements-with-class'],
-          {'action': 'append', 'dest': 'strip_elements_with_classes',
-           'metavar': '<class>', 'validator': validate_strip_class}),
-         ('Remove all classes="<class>" attributes from elements in the '
-          'document tree. Warning: potentially dangerous; use with caution. '
-          '(Multiple-use option.)',
-          ['--strip-class'],
-          {'action': 'append', 'dest': 'strip_classes',
-           'metavar': '<class>', 'validator': validate_strip_class}),
-         ('Report system messages at or higher than <level>: "info" or "1", '
-          '"warning"/"2" (default), "error"/"3", "severe"/"4", "none"/"5"',
-          ['--report', '-r'], {'choices': threshold_choices, 'default': 2,
-                               'dest': 'report_level', 'metavar': '<level>',
-                               'validator': validate_threshold}),
-         ('Report all system messages.  (Same as "--report=1".)',
-          ['--verbose', '-v'], {'action': 'store_const', 'const': 1,
-                                'dest': 'report_level'}),
-         ('Report no system messages.  (Same as "--report=5".)',
-          ['--quiet', '-q'], {'action': 'store_const', 'const': 5,
-                              'dest': 'report_level'}),
-         ('Halt execution at system messages at or above <level>.  '
-          'Levels as in --report.  Default: 4 (severe).',
-          ['--halt'], {'choices': threshold_choices, 'dest': 'halt_level',
-                       'default': 4, 'metavar': '<level>',
-                       'validator': validate_threshold}),
-         ('Halt at the slightest problem.  Same as "--halt=info".',
-          ['--strict'], {'action': 'store_const', 'const': 1,
-                         'dest': 'halt_level'}),
-         ('Enable a non-zero exit status for non-halting system messages at '
-          'or above <level>.  Default: 5 (disabled).',
-          ['--exit-status'], {'choices': threshold_choices,
-                              'dest': 'exit_status_level',
-                              'default': 5, 'metavar': '<level>',
-                              'validator': validate_threshold}),
-         ('Enable debug-level system messages and diagnostics.',
-          ['--debug'], {'action': 'store_true', 'validator': validate_boolean}),
-         ('Disable debug output.  (default)',
-          ['--no-debug'], {'action': 'store_false', 'dest': 'debug'}),
-         ('Send the output of system messages to <file>.',
-          ['--warnings'], {'dest': 'warning_stream', 'metavar': '<file>'}),
-         ('Enable Python tracebacks when Docutils is halted.',
-          ['--traceback'], {'action': 'store_true', 'default': None,
-                            'validator': validate_boolean}),
-         ('Disable Python tracebacks.  (default)',
-          ['--no-traceback'], {'dest': 'traceback', 'action': 'store_false'}),
-         ('Specify the encoding and optionally the '
-          'error handler of input text.  Default: <locale-dependent>:strict.',
-          ['--input-encoding', '-i'],
-          {'metavar': '<name[:handler]>',
-           'validator': validate_encoding_and_error_handler}),
-         ('Specify the error handler for undecodable characters.  '
-          'Choices: "strict" (default), "ignore", and "replace".',
-          ['--input-encoding-error-handler'],
-          {'default': 'strict', 'validator': validate_encoding_error_handler}),
-         ('Specify the text encoding and optionally the error handler for '
-          'output.  Default: UTF-8:strict.',
-          ['--output-encoding', '-o'],
-          {'metavar': '<name[:handler]>', 'default': 'utf-8',
-           'validator': validate_encoding_and_error_handler}),
-         ('Specify error handler for unencodable output characters; '
-          '"strict" (default), "ignore", "replace", '
-          '"xmlcharrefreplace", "backslashreplace".',
-          ['--output-encoding-error-handler'],
-          {'default': 'strict', 'validator': validate_encoding_error_handler}),
-         ('Specify text encoding and error handler for error output.  '
-          'Default: %s:%s.'
-          % (default_error_encoding, default_error_encoding_error_handler),
-          ['--error-encoding', '-e'],
-          {'metavar': '<name[:handler]>', 'default': default_error_encoding,
-           'validator': validate_encoding_and_error_handler}),
-         ('Specify the error handler for unencodable characters in '
-          'error output.  Default: %s.'
-          % default_error_encoding_error_handler,
-          ['--error-encoding-error-handler'],
-          {'default': default_error_encoding_error_handler,
-           'validator': validate_encoding_error_handler}),
-         ('Specify the language (as BCP 47 language tag).  Default: en.',
-          ['--language', '-l'], {'dest': 'language_code', 'default': 'en',
-                                 'metavar': '<name>'}),
-         ('Write output file dependencies to <file>.',
-          ['--record-dependencies'],
-          {'metavar': '<file>', 'validator': validate_dependency_file,
-           'default': None}),           # default set in Values class
-         ('Read configuration settings from <file>, if it exists.',
-          ['--config'], {'metavar': '<file>', 'type': 'string',
-                         'action': 'callback', 'callback': read_config_file}),
-         ("Show this program's version number and exit.",
-          ['--version', '-V'], {'action': 'version'}),
-         ('Show this help message and exit.',
-          ['--help', '-h'], {'action': 'help'}),
-         # Typically not useful for non-programmatical use:
-         (SUPPRESS_HELP, ['--id-prefix'], {'default': ''}),
-         (SUPPRESS_HELP, ['--auto-id-prefix'], {'default': 'id'}),
-         # Hidden options, for development use only:
-         (SUPPRESS_HELP, ['--dump-settings'], {'action': 'store_true'}),
-         (SUPPRESS_HELP, ['--dump-internals'], {'action': 'store_true'}),
-         (SUPPRESS_HELP, ['--dump-transforms'], {'action': 'store_true'}),
-         (SUPPRESS_HELP, ['--dump-pseudo-xml'], {'action': 'store_true'}),
-         (SUPPRESS_HELP, ['--expose-internal-attribute'],
-          {'action': 'append', 'dest': 'expose_internals',
-           'validator': validate_colon_separated_string_list}),
-         (SUPPRESS_HELP, ['--strict-visitor'], {'action': 'store_true'}),
-         ))
-    """Runtime settings and command-line options common to all Docutils front
-    ends.  Setting specs specific to individual Docutils components are also
-    used (see `populate_from_components()`)."""
-
-    settings_defaults = {'_disable_config': None,
-                         '_source': None,
-                         '_destination': None,
-                         '_config_files': None}
-    """Defaults for settings that don't have command-line option equivalents."""
-
-    relative_path_settings = ('warning_stream',)
-
-    config_section = 'general'
-
-    version_template = ('%%prog (Docutils %s%s, Python %s, on %s)'
-                        % (docutils.__version__,
-                           docutils.__version_details__ and
-                           ' [%s]'%docutils.__version_details__ or '',
-                           sys.version.split()[0], sys.platform))
-    """Default version message."""
-
-    def __init__(self, components=(), defaults=None, read_config_files=None,
-                 *args, **kwargs):
-        """
-        `components` is a list of Docutils components each containing a
-        ``.settings_spec`` attribute.  `defaults` is a mapping of setting
-        default overrides.
-        """
-
-        self.lists = {}
-        """Set of list-type settings."""
-
-        self.config_files = []
-        """List of paths of applied configuration files."""
-
-        optparse.OptionParser.__init__(
-            self, option_class=Option, add_help_option=None,
-            formatter=optparse.TitledHelpFormatter(width=78),
-            *args, **kwargs)
-        if not self.version:
-            self.version = self.version_template
-        # Make an instance copy (it will be modified):
-        self.relative_path_settings = list(self.relative_path_settings)
-        self.components = (self,) + tuple(components)
-        self.populate_from_components(self.components)
-        self.set_defaults_from_dict(defaults or {})
-        if read_config_files and not self.defaults['_disable_config']:
-            try:
-                config_settings = self.get_standard_config_settings()
-            except ValueError as error:
-                self.error(SafeString(error))
-            self.set_defaults_from_dict(config_settings.__dict__)
-
-    def populate_from_components(self, components):
-        """
-        For each component, first populate from the `SettingsSpec.settings_spec`
-        structure, then from the `SettingsSpec.settings_defaults` dictionary.
-        After all components have been processed, check for and populate from
-        each component's `SettingsSpec.settings_default_overrides` dictionary.
-        """
-        for component in components:
-            if component is None:
-                continue
-            settings_spec = component.settings_spec
-            self.relative_path_settings.extend(
-                component.relative_path_settings)
-            for i in range(0, len(settings_spec), 3):
-                title, description, option_spec = settings_spec[i:i+3]
-                if title:
-                    group = optparse.OptionGroup(self, title, description)
-                    self.add_option_group(group)
-                else:
-                    group = self        # single options
-                for (help_text, option_strings, kwargs) in option_spec:
-                    option = group.add_option(help=help_text, *option_strings,
-                                              **kwargs)
-                    if kwargs.get('action') == 'append':
-                        self.lists[option.dest] = 1
-                if component.settings_defaults:
-                    self.defaults.update(component.settings_defaults)
-        for component in components:
-            if component and component.settings_default_overrides:
-                self.defaults.update(component.settings_default_overrides)
-
-    def get_standard_config_files(self):
-        """Return list of config files, from environment or standard."""
-        try:
-            config_files = os.environ['DOCUTILSCONFIG'].split(os.pathsep)
-        except KeyError:
-            config_files = self.standard_config_files
-
-        # If 'HOME' is not set, expandvars() requires the 'pwd' module which is
-        # not available under certain environments, for example, within
-        # mod_python.  The publisher ends up in here, and we need to publish
-        # from within mod_python.  Therefore we need to avoid expanding when we
-        # are in those environments.
-        expand = os.path.expanduser
-        if 'HOME' not in os.environ:
-            try:
-                import pwd
-            except ImportError:
-                expand = lambda x: x
-        return [expand(f) for f in config_files if f.strip()]
-
-    def get_standard_config_settings(self):
-        settings = Values()
-        for filename in self.get_standard_config_files():
-            settings.update(self.get_config_file_settings(filename), self)
-        return settings
-
-    def get_config_file_settings(self, config_file):
-        """Returns a dictionary containing appropriate config file settings."""
-        parser = ConfigParser()
-        parser.read(config_file, self)
-        self.config_files.extend(parser._files)
-        base_path = os.path.dirname(config_file)
-        applied = {}
-        settings = Values()
-        for component in self.components:
-            if not component:
-                continue
-            for section in (tuple(component.config_section_dependencies or ())
-                            + (component.config_section,)):
-                if section in applied:
-                    continue
-                applied[section] = 1
-                settings.update(parser.get_section(section), self)
-        make_paths_absolute(
-            settings.__dict__, self.relative_path_settings, base_path)
-        return settings.__dict__
-
-    def check_values(self, values, args):
-        """Store positional arguments as runtime settings."""
-        values._source, values._destination = self.check_args(args)
-        make_paths_absolute(values.__dict__, self.relative_path_settings)
-        values._config_files = self.config_files
-        return values
-
-    def check_args(self, args):
-        source = destination = None
-        if args:
-            source = args.pop(0)
-            if source == '-':           # means stdin
-                source = None
-        if args:
-            destination = args.pop(0)
-            if destination == '-':      # means stdout
-                destination = None
-        if args:
-            self.error('Maximum 2 arguments allowed.')
-        if source and source == destination:
-            self.error('Do not specify the same file for both source and '
-                       'destination.  It will clobber the source file.')
-        return source, destination
-
-    def set_defaults_from_dict(self, defaults):
-        self.defaults.update(defaults)
-
-    def get_default_values(self):
-        """Needed to get custom `Values` instances."""
-        defaults = Values(self.defaults)
-        defaults._config_files = self.config_files
-        return defaults
-
-    def get_option_by_dest(self, dest):
-        """
-        Get an option by its dest.
-
-        If you're supplying a dest which is shared by several options,
-        it is undefined which option of those is returned.
-
-        A KeyError is raised if there is no option with the supplied
-        dest.
-        """
-        for group in self.option_groups + [self]:
-            for option in group.option_list:
-                if option.dest == dest:
-                    return option
-        raise KeyError('No option with dest == %r.' % dest)
-
-
-class ConfigParser(RawConfigParser):
-
-    old_settings = {
-        'pep_stylesheet': ('pep_html writer', 'stylesheet'),
-        'pep_stylesheet_path': ('pep_html writer', 'stylesheet_path'),
-        'pep_template': ('pep_html writer', 'template')}
-    """{old setting: (new section, new setting)} mapping, used by
-    `handle_old_config`, to convert settings from the old [options] section."""
-
-    old_warning = """
-The "[option]" section is deprecated.  Support for old-format configuration
-files may be removed in a future Docutils release.  Please revise your
-configuration files.  See <http://docutils.sf.net/docs/user/config.html>,
-section "Old-Format Configuration Files".
-"""
-
-    not_utf8_error = """\
-Unable to read configuration file "%s": content not encoded as UTF-8.
-Skipping "%s" configuration file.
-"""
-
-    def __init__(self, *args, **kwargs):
-        RawConfigParser.__init__(self, *args, **kwargs)
-
-        self._files = []
-        """List of paths of configuration files read."""
-
-        self._stderr = ErrorOutput()
-        """Wrapper around sys.stderr catching en-/decoding errors"""
-
-    def read(self, filenames, option_parser):
-        if type(filenames) in (str, unicode):
-            filenames = [filenames]
-        for filename in filenames:
-            try:
-                # Config files must be UTF-8-encoded:
-                fp = codecs.open(filename, 'r', 'utf-8')
-            except IOError:
-                continue
-            try:
-                if sys.version_info < (3, 0):
-                    RawConfigParser.readfp(self, fp, filename)
-                else:
-                    RawConfigParser.read_file(self, fp, filename)
-            except UnicodeDecodeError:
-                self._stderr.write(self.not_utf8_error % (filename, filename))
-                fp.close()
-                continue
-            fp.close()
-            self._files.append(filename)
-            if self.has_section('options'):
-                self.handle_old_config(filename)
-            self.validate_settings(filename, option_parser)
-
-    def handle_old_config(self, filename):
-        warnings.warn_explicit(self.old_warning, ConfigDeprecationWarning,
-                               filename, 0)
-        options = self.get_section('options')
-        if not self.has_section('general'):
-            self.add_section('general')
-        for key, value in options.items():
-            if key in self.old_settings:
-                section, setting = self.old_settings[key]
-                if not self.has_section(section):
-                    self.add_section(section)
-            else:
-                section = 'general'
-                setting = key
-            if not self.has_option(section, setting):
-                self.set(section, setting, value)
-        self.remove_section('options')
-
-    def validate_settings(self, filename, option_parser):
-        """
-        Call the validator function and implement overrides on all applicable
-        settings.
-        """
-        for section in self.sections():
-            for setting in self.options(section):
-                try:
-                    option = option_parser.get_option_by_dest(setting)
-                except KeyError:
-                    continue
-                if option.validator:
-                    value = self.get(section, setting)
-                    try:
-                        new_value = option.validator(
-                            setting, value, option_parser,
-                            config_parser=self, config_section=section)
-                    except Exception as error:
-                        raise ValueError(
-                            'Error in config file "%s", section "[%s]":\n'
-                            '    %s\n'
-                            '        %s = %s'
-                            % (filename, section, ErrorString(error),
-                               setting, value))
-                    self.set(section, setting, new_value)
-                if option.overrides:
-                    self.set(section, option.overrides, None)
-
-    def optionxform(self, optionstr):
-        """
-        Transform '-' to '_' so the cmdline form of option names can be used.
-        """
-        return optionstr.lower().replace('-', '_')
-
-    def get_section(self, section):
-        """
-        Return a given section as a dictionary (empty if the section
-        doesn't exist).
-        """
-        section_dict = {}
-        if self.has_section(section):
-            for option in self.options(section):
-                section_dict[option] = self.get(section, option)
-        return section_dict
-
-
-class ConfigDeprecationWarning(DeprecationWarning):
-    """Warning for deprecated configuration file features."""