Add reset support to TOC extension.

Now, whenever the TOC extensiuon is loaded, the Markdown class instance
will always have a toc attribute (md.toc). Calling md.reset() will also
reset the toc attribute which defaults to an empty string.

2 files changed, 14 insertions, 0 deletions

diff --git a/markdown/extensions/toc.py b/markdown/extensions/toc.py
index 99542ed..db6659c 100644
--- a/markdown/extensions/toc.py
+++ b/markdown/extensions/toc.py
@@ -234,6 +234,9 @@ class TocExtension(Extension):
         super(TocExtension, self).__init__(*args, **kwargs)
 
     def extendMarkdown(self, md, md_globals):
+        md.registerExtension(self)
+        self.md = md
+        self.reset()
         tocext = self.TreeProcessorClass(md)
         tocext.config = self.getConfigs()
         # Headerid ext is set to '>prettify'. With this set to '_end',
@@ -243,6 +246,9 @@ class TocExtension(Extension):
         # to redefine ids after toc is created. But we do want toc prettified.
         md.treeprocessors.add("toc", tocext, "_end")
 
+    def reset(self):
+        self.md.toc = ''
+
 
 def makeExtension(*args, **kwargs):
     return TocExtension(*args, **kwargs)
diff --git a/tests/test_extensions.py b/tests/test_extensions.py
index e24118f..2380f17 100644
--- a/tests/test_extensions.py
+++ b/tests/test_extensions.py
@@ -733,6 +733,14 @@ class TestTOC(unittest.TestCase):
             '</div>\n'
         )
 
+    def testReset(self):
+        """ Test TOC Reset. """
+        self.assertEqual(self.md.toc, '')
+        self.md.convert('# Header 1\n\n## Header 2')
+        self.assertTrue(self.md.toc.startswith('<div class="toc">'))
+        self.md.reset()
+        self.assertEqual(self.md.toc, '')
+
 
 class TestSmarty(unittest.TestCase):
     def setUp(self):