Revert of Check in a simple pure-python based Markdown previewer.

third_party/Python-Markdown/markdown/extensions/headerid.py

-"""
-HeaderID Extension for Python-Markdown
-======================================
-
-Auto-generate id attributes for HTML headers.
-
-See <https://pythonhosted.org/Markdown/extensions/header_id.html>
-for documentation.
-
-Original code Copyright 2007-2011 [Waylan Limberg](http://achinghead.com/).
-
-All changes Copyright 2011-2014 The Python Markdown Project
-
-License: [BSD](http://www.opensource.org/licenses/bsd-license.php)
-
-"""
-
-from __future__ import absolute_import
-from __future__ import unicode_literals
-from . import Extension
-from ..treeprocessors import Treeprocessor
-from ..util import parseBoolValue
-from .toc import slugify, unique, stashedHTML2text
-import warnings
-
-
-class HeaderIdTreeprocessor(Treeprocessor):
-    """ Assign IDs to headers. """
-
-    IDs = set()
-
-    def run(self, doc):
-        start_level, force_id = self._get_meta()
-        slugify = self.config['slugify']
-        sep = self.config['separator']
-        for elem in doc:
-            if elem.tag in ['h1', 'h2', 'h3', 'h4', 'h5', 'h6']:
-                if force_id:
-                    if "id" in elem.attrib:
-                        id = elem.get('id')
-                    else:
-                        id = stashedHTML2text(''.join(elem.itertext()), self.md)
-                        id = slugify(id, sep)
-                    elem.set('id', unique(id, self.IDs))
-                if start_level:
-                    level = int(elem.tag[-1]) + start_level
-                    if level > 6:
-                        level = 6
-                    elem.tag = 'h%d' % level
-
-    def _get_meta(self):
-        """ Return meta data suported by this ext as a tuple """
-        level = int(self.config['level']) - 1
-        force = parseBoolValue(self.config['forceid'])
-        if hasattr(self.md, 'Meta'):
-            if 'header_level' in self.md.Meta:
-                level = int(self.md.Meta['header_level'][0]) - 1
-            if 'header_forceid' in self.md.Meta:
-                force = parseBoolValue(self.md.Meta['header_forceid'][0])
-        return level, force
-
-
-class HeaderIdExtension(Extension):
-    def __init__(self, *args, **kwargs):
-        # set defaults
-        self.config = {
-            'level': ['1', 'Base level for headers.'],
-            'forceid': ['True', 'Force all headers to have an id.'],
-            'separator': ['-', 'Word separator.'],
-            'slugify': [slugify, 'Callable to generate anchors']
-        }
-
-        super(HeaderIdExtension, self).__init__(*args, **kwargs)
-
-        warnings.warn(
-            'The HeaderId Extension is pending deprecation. Use the TOC Extension instead.',
-            PendingDeprecationWarning
-        )
-
-    def extendMarkdown(self, md, md_globals):
-        md.registerExtension(self)
-        self.processor = HeaderIdTreeprocessor()
-        self.processor.md = md
-        self.processor.config = self.getConfigs()
-        if 'attr_list' in md.treeprocessors.keys():
-            # insert after attr_list treeprocessor
-            md.treeprocessors.add('headerid', self.processor, '>attr_list')
-        else:
-            # insert after 'prettify' treeprocessor.
-            md.treeprocessors.add('headerid', self.processor, '>prettify')
-
-    def reset(self):
-        self.processor.IDs = set()
-
-
-def makeExtension(*args, **kwargs):
-    return HeaderIdExtension(*args, **kwargs)