Add md-footnote

crates/lib/md-footnote/tests/fixtures/9.md

@@ -0,0 +1,37 @@
+Nested blocks
+
+......
+
+[^a]
+
+[^a]: abc
+
+    def
+hij
+
+    - list
+
+    > block
+
+terminates here
+
+......
+
+<p data-sourcepos="1:1-1:4"><sup data-sourcepos="1:1-1:4" class="footnote-ref"><a href="#fn1" id="fnref1">[1]</a></sup></p>
+<p data-sourcepos="12:1-12:15">terminates here</p>
+<hr class="footnotes-sep">
+<section class="footnotes">
+<ol class="footnotes-list">
+<li data-sourcepos="3:1-11:0" id="fn1" class="footnote-item">
+<p data-sourcepos="3:7-3:9">abc</p>
+<p data-sourcepos="5:5-6:3">def
+hij</p>
+<ul data-sourcepos="8:5-9:0">
+<li data-sourcepos="8:5-9:0">list</li>
+</ul>
+<blockquote data-sourcepos="10:5-10:11">
+<p data-sourcepos="10:7-10:11">block</p>
+</blockquote>
+ <a href="#fnref1" class="footnote-backref">↩︎</a></li>
+</ol>
+</section>