md_tw: Add TWBlockLexer.parse_heading.

* md_tw.py
(TWBlockLexer.parse_heading): New method.
* tests/data/blexer-heading.md: New file.
* tests/test_md_tw.py
(TestTWBlockLexer.test_parse_heading): New test.

1 files changed, 7 insertions, 0 deletions

diff --git a/md_tw.py b/md_tw.py
index 218d324..64c9ced 100644
--- a/md_tw.py
+++ b/md_tw.py
@@ -52,6 +52,13 @@ class TWBlockLexer(mistune.BlockLexer):
             'text': m.group(0),
         })
 
+    def parse_heading(self, m):
+        self.tokens.append({
+            'type': 'heading',
+            'level': len(m.group(1)),
+            'text': m.group(0),
+        })
+
 
 class TWInlineLexer(mistune.InlineLexer):
     """Text Wrap Inline level lexer for inline gramars."""