{"ast_node_type":"other","tokens":[{"end":79,"kind":"keyword","start":0,"text":"assert_eq!(t,"}]}
    assert_eq!(t, MdTree::Heading(1, vec![MdTree::PlainText("Empty")].into()));
    let (t, r) = parse_heading(buf1.as_bytes()).unwrap();
    assert_eq!(r, b"");