Refactored HeaderId extension to no longer include defining ids. It only autogenerates ids. If you want to define your own, use the attr_list extension. Also expanded HeaderId extension to use the same algorithm as the TOC extension (which is better) for slugifying the header text. Added config settings to override the default word separator and the slugify callable. Closes #16 as the reported bug is for a removed feature.

1 files changed, 75 insertions, 77 deletions

diff --git a/markdown/extensions/headerid.py b/markdown/extensions/headerid.py
index 9c36a2b..e967648 100644
--- a/markdown/extensions/headerid.py
+++ b/markdown/extensions/headerid.py
@@ -4,25 +4,25 @@
 HeaderID Extension for Python-Markdown
 ======================================
 
-Adds ability to set HTML IDs for headers.
+Auto-generate id attributes for HTML headers.
 
 Basic usage:
 
     >>> import markdown
-    >>> text = "# Some Header # {#some_id}"
+    >>> text = "# Some Header #"
     >>> md = markdown.markdown(text, ['headerid'])
     >>> md
-    u'<h1 id="some_id">Some Header</h1>'
+    u'<h1 id="some-header">Some Header</h1>'
 
 All header IDs are unique:
 
     >>> text = '''
     ... #Header
-    ... #Another Header {#header}
-    ... #Third Header {#header}'''
+    ... #Header
+    ... #Header'''
     >>> md = markdown.markdown(text, ['headerid'])
     >>> md
-    u'<h1 id="header">Header</h1>\\n<h1 id="header_1">Another Header</h1>\\n<h1 id="header_2">Third Header</h1>'
+    u'<h1 id="header">Header</h1>\\n<h1 id="header_1">Header</h1>\\n<h1 id="header_2">Header</h1>'
 
 To fit within a html template's hierarchy, set the header base level:
 
@@ -31,16 +31,23 @@ To fit within a html template's hierarchy, set the header base level:
     ... ## Next Level'''
     >>> md = markdown.markdown(text, ['headerid(level=3)'])
     >>> md
-    u'<h3 id="some_header">Some Header</h3>\\n<h4 id="next_level">Next Level</h4>'
+    u'<h3 id="some-header">Some Header</h3>\\n<h4 id="next-level">Next Level</h4>'
+
+Works with inline markup.
+
+    >>> text = '#Some *Header* with [markup](http://example.com).'
+    >>> md = markdown.markdown(text, ['headerid'])
+    >>> md
+    u'<h1 id="some-header-with-markup">Some <em>Header</em> with <a href="http://example.com">markup</a>.</h1>'
 
 Turn off auto generated IDs:
 
     >>> text = '''
     ... # Some Header
-    ... # Header with ID # { #foo }'''
+    ... # Another Header'''
     >>> md = markdown.markdown(text, ['headerid(forceid=False)'])
     >>> md
-    u'<h1>Some Header</h1>\\n<h1 id="foo">Header with ID</h1>'
+    u'<h1>Some Header</h1>\\n<h1>Another Header</h1>'
 
 Use with MetaData extension:
 
@@ -52,7 +59,7 @@ Use with MetaData extension:
     >>> md
     u'<h2>A Header</h2>'
 
-Copyright 2007-2008 [Waylan Limberg](http://achinghead.com/).
+Copyright 2007-2011 [Waylan Limberg](http://achinghead.com/).
 
 Project website: <http://www.freewisdom.org/project/python-markdown/HeaderId>
 Contact: markdown@freewisdom.org
@@ -70,59 +77,70 @@ from markdown.util import etree
 import re
 from string import ascii_lowercase, digits, punctuation
 import logging
+import unicodedata
 
 logger = logging.getLogger('MARKDOWN')
 
-ID_CHARS = ascii_lowercase + digits + '-_.'
 IDCOUNT_RE = re.compile(r'^(.*)_([0-9]+)$')
 
 
-class HeaderIdProcessor(markdown.blockprocessors.BlockProcessor):
-    """ Replacement BlockProcessor for Header IDs. """
+def slugify(value, separator):
+    """ Slugify a string, to make it URL friendly. """
+    value = unicodedata.normalize('NFKD', value).encode('ascii', 'ignore')
+    value = unicode(re.sub('[^\w\s-]', '', value).strip().lower())
+    return re.sub('[%s\s]+' % separator, separator, value)
 
-    # Detect a header at start of any line in block
-    RE = re.compile(r"""(^|\n)
-                        (?P<level>\#{1,6})  # group('level') = string of hashes
-                        (?P<header>.*?)     # group('header') = Header text
-                        \#*                 # optional closing hashes
-                        (?:[ \t]*\{[ \t]*\#(?P<id>[-_.:a-zA-Z0-9]+)[ \t]*\})?
-                        (\n|$)              #  ^^ group('id') = id attribute
-                     """,
-                     re.VERBOSE)
 
-    IDs = []
-
-    def test(self, parent, block):
-        return bool(self.RE.search(block))
-
-    def run(self, parent, blocks):
-        block = blocks.pop(0)
-        m = self.RE.search(block)
+def unique(id, ids):
+    """ Ensure id is unique in set of ids. Append '_1', '_2'... if not """
+    while id in ids:
+        m = IDCOUNT_RE.match(id)
         if m:
-            before = block[:m.start()] # All lines before header
-            after = block[m.end():]    # All lines after header
-            if before:
-                # As the header was not the first line of the block and the
-                # lines before the header must be parsed first,
-                # recursively parse this lines as a block.
-                self.parser.parseBlocks(parent, [before])
-            # Create header using named groups from RE
-            start_level, force_id = self._get_meta()
-            level = len(m.group('level')) + start_level
-            if level > 6: 
-                level = 6
-            h = etree.SubElement(parent, 'h%d' % level)
-            h.text = m.group('header').strip()
-            if m.group('id'):
-                h.set('id', self._unique_id(m.group('id')))
-            elif force_id:
-                h.set('id', self._create_id(m.group('header').strip()))
-            if after:
-                # Insert remaining lines as first block for future parsing.
-                blocks.insert(0, after)
+            id = '%s_%d'% (m.group(1), int(m.group(2))+1)
         else:
-            # This should never happen, but just in case...
-            logger.warn("We've got a problem header: %r" % block)
+            id = '%s_%d'% (id, 1)
+    ids.append(id)
+    return id
+
+
+def itertext(elem):
+    """ Loop through all children and return text only. 
+    
+    Reimplements method of same name added to ElementTree in Python 2.7
+    
+    """
+    if elem.text:
+        yield elem.text
+    for e in elem:
+        for s in itertext(e):
+            yield s
+        if e.tail:
+            yield e.tail
+
+
+class HeaderIdTreeprocessor(markdown.treeprocessors.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.getiterator():
+            if elem.tag in ['h1', 'h2', 'h3', 'h4', 'h5', 'h6']:
+                if force_id:
+                    if "id" in elem.attrib:
+                        id = elem.id
+                    else:
+                        id = slugify(''.join(itertext(elem)), 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 """
@@ -144,27 +162,6 @@ class HeaderIdProcessor(markdown.blockprocessors.BlockProcessor):
             return True
         return default
 
-    def _unique_id(self, id):
-        """ Ensure ID is unique. Append '_1', '_2'... if not """
-        while id in self.IDs:
-            m = IDCOUNT_RE.match(id)
-            if m:
-                id = '%s_%d'% (m.group(1), int(m.group(2))+1)
-            else:
-                id = '%s_%d'% (id, 1)
-        self.IDs.append(id)
-        return id
-
-    def _create_id(self, header):
-        """ Return ID from Header text. """
-        h = ''
-        for c in header.lower().replace(' ', self.config['separator']):
-            if c in ID_CHARS:
-                h += c
-            elif c not in punctuation:
-                h += '+'
-        return self._unique_id(h)
-
 
 class HeaderIdExtension (markdown.Extension):
     def __init__(self, configs):
@@ -172,7 +169,8 @@ class HeaderIdExtension (markdown.Extension):
         self.config = {
                 'level' : ['1', 'Base level for headers.'],
                 'forceid' : ['True', 'Force all headers to have an id.'],
-                'separator' : ['_', 'Word separator.'],
+                'separator' : ['-', 'Word separator.'],
+                'slugify' : [slugify, 'Callable to generate anchors'], 
             }
 
         for key, value in configs:
@@ -180,11 +178,11 @@ class HeaderIdExtension (markdown.Extension):
 
     def extendMarkdown(self, md, md_globals):
         md.registerExtension(self)
-        self.processor = HeaderIdProcessor(md.parser)
+        self.processor = HeaderIdTreeprocessor()
         self.processor.md = md
         self.processor.config = self.getConfigs()
         # Replace existing hasheader in place.
-        md.parser.blockprocessors['hashheader'] = self.processor
+        md.treeprocessors.add('headerid', self.processor, '>inline')
 
     def reset(self):
         self.processor.IDs = []