add test

tests/sphinx_custom_md/index.markdown

@@ -13,3 +13,10 @@ A paragraph
 
 Another paragraph
 
+
+```eval_rst
+.. contents:: Contents
+```
+
+Header 2
+----------

tests/test_sphinx.py

@@ -210,3 +210,13 @@ class CustomExtensionTests(SphinxIntegrationTests):
         self.assertIn('<th class="head">abc</th>', output)
         self.assertIn('<th class="head">data</th>', output)
         self.assertIn('</table>', output)
+
+        self.assertIn(
+            ('<div class="contents topic" id="contents">\n'
+             '<p class="topic-title first">Contents</p>\n'
+             '<ul class="simple">\n'
+             '<li><a class="reference internal" href="#header" id="id1">Header</a><ul>\n'
+             '<li><a class="reference internal" href="#header-2" id="id2">Header 2</a></li>\n'
+             '</ul>\n</li>\n</ul>'),
+            output
+            )