md_tw.py: Add TWMarkdown.output_heading.

Add prefix, if it exists, to heading.

* md_tw.py (TWMarkdown.output_heading): Override super class's method.
* tests/data/renderer-heading-w.md: Update file.
* tests/data/renderer-heading.md: Update file.

1 files changed, 8 insertions, 0 deletions

diff --git a/md_tw.py b/md_tw.py
index b61c409..866f1fa 100644
--- a/md_tw.py
+++ b/md_tw.py
@@ -356,6 +356,14 @@ class TWMarkdown(mistune.Markdown):
         if subseq:
             self.renderer.tw_set(subsequent_indent=p)
 
+    def output_heading(self):
+        rendered_heading = '{}{}'.format(
+            self.renderer.tw_get('initial_indent'),
+            super(TWMarkdown, self).output_heading()
+        )
+
+        return rendered_heading
+
     def output_block_quote(self):
         # Add prefix
         self._add_prefix('> ')