1 files changed, 105 insertions, 0 deletions
diff --git a/mdx_fenced_code.py b/mdx_fenced_code.py
new file mode 100644
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+++ b/mdx_fenced_code.py
@@ -0,0 +1,105 @@
+#!/usr/bin/env python
+
+"""
+Fenced Code Extension for Python Markdown
+=========================================
+
+This extension adds Fenced Code Blocks to Python-Markdown.
+
+    >>> import markdown
+    >>> text = '''
+    ... A paragraph before a fenced code block:
+    ... 
+    ... ~~~
+    ... Fenced code block
+    ... ~~~
+    ... '''
+    >>> html = markdown.markdown(text, extensions=['fenced_code'])
+    >>> html
+    u'<p>A paragraph before a fenced code block:\\n</p>\\n<pre><code>Fenced code block\\n<code><pre>'
+
+Works with safe_mode also (we check this because we are using the HtmlStash):
+
+    >>> markdown.markdown(text, extensions=['fenced_code'], safe_mode='replace')
+    u'<p>A paragraph before a fenced code block:\\n</p>\\n<pre><code>Fenced code block\\n<code><pre>'
+    
+Include tilde's in a code block and wrap with blank lines:
+
+    >>> text = '''
+    ... ~~~~~~~~
+    ... 
+    ... ~~~~
+    ... 
+    ... ~~~~~~~~'''
+    >>> markdown.markdown(text, extensions=['fenced_code'])
+    u'<pre><code>\\n~~~~\\n\\n<code><pre>'
+
+Multiple blocks and language tags:
+
+    >>> text = '''
+    ... ~~~~
+    ... block one
+    ... ~~~~{.python}
+    ... 
+    ... ~~~~
+    ... <p>block two</p>
+    ... ~~~~{.html}'''
+    >>> markdown.markdown(text, extensions=['fenced_code'])
+    u'<pre><code class="python">block one\\n<code><pre>\\n\\n<pre><code class="html">&lt;p&gt;block two&lt;/p&gt;\\n<code><pre>'
+
+"""
+
+import markdown, re
+
+# Global vars
+FENCED_BLOCK_RE = re.compile( \
+    r'(?P<fence>^~{3,})[ ]*\n(?P<code>.*?)(?P=fence)[ ]*(\{\.(?P<lang>[a-zA-Z0-9_-]*)\})?[ ]*$', 
+    re.MULTILINE|re.DOTALL
+    )
+CODE_WRAP = '<pre><code%s>%s<code><pre>'
+LANG_TAG = ' class="%s"'
+
+
+class FencedCodeExtension(markdown.Extension):
+
+    def extendMarkdown(self, md, md_globals):
+        """ Add FencedBlockPreprocessor to the Markdown instance. """
+
+        FENCED_BLOCK_PREPROCESSOR = FencedBlockPreprocessor()
+        FENCED_BLOCK_PREPROCESSOR.md = md
+        md.textPreprocessors.insert(0, FENCED_BLOCK_PREPROCESSOR)
+
+
+class FencedBlockPreprocessor(markdown.TextPreprocessor):
+    
+    def run(self, text):
+        """ Match and store Fenced Code Blocks in the HtmlStash. """
+        while 1:
+            m = FENCED_BLOCK_RE.search(text)
+            if m:
+                lang = ''
+                if m.group('lang'):
+                    lang = LANG_TAG % m.group('lang')
+                code = CODE_WRAP % (lang, self._escape(m.group('code')))
+                placeholder = self.md.htmlStash.store(code, safe=True)
+                text = '%s\n%s\n%s'% (text[:m.start()], placeholder, text[m.end():])
+            else:
+                break
+        return text
+
+    def _escape(self, txt):
+        """ basic html escaping """
+        txt = txt.replace('&', '&amp;')
+        txt = txt.replace('<', '&lt;')
+        txt = txt.replace('>', '&gt;')
+        txt = txt.replace('"', '&quot;')
+        return txt
+
+
+def makeExtension(configs=None):
+    return FencedCodeExtension()
+
+
+if __name__ == "__main__":
+    import doctest
+    doctest.testmod()