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

Index: third_party/Python-Markdown/markdown/extensions/headerid.py
diff --git a/third_party/Python-Markdown/markdown/extensions/headerid.py b/third_party/Python-Markdown/markdown/extensions/headerid.py
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index 0000000000000000000000000000000000000000..2cb20b97ab6c4901bc3626643e869236d2961e6b
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+++ b/third_party/Python-Markdown/markdown/extensions/headerid.py
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+"""
+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)