Add test case for footnote with non-number label

org/testdata/footnotes.html

@@ -12,7 +12,7 @@ Using some footnotes
 <ul>
 <li>
 <p>
-normal footnote reference <sup class="footnote-reference"><a id="footnote-reference-0" href="#footnote-0">0</a></sup> <sup class="footnote-reference"><a id="footnote-reference-1" href="#footnote-1">1</a></sup>
+normal footnote reference <sup class="footnote-reference"><a id="footnote-reference-0" href="#footnote-0">0</a></sup> <sup class="footnote-reference"><a id="footnote-reference-1" href="#footnote-1">1</a></sup> <sup class="footnote-reference"><a id="footnote-reference-2" href="#footnote-2">2</a></sup> (footnote names can be anything in the format <code class="verbatim">[\w-]</code>)
 </p>
 </li>
 <li>
@@ -22,18 +22,18 @@ further references to the same footnote should not <sup class="footnote-referenc
 </li>
 <li>
 <p>
-inline footnotes are also supported via <sup class="footnote-reference"><a id="footnote-reference-2" href="#footnote-2">2</a></sup>.
+inline footnotes are also supported via <sup class="footnote-reference"><a id="footnote-reference-3" href="#footnote-3">3</a></sup>.
 </p>
 </li>
 <li>
 <p>
-anonymous inline footnotes are also supported via <sup class="footnote-reference"><a id="footnote-reference-3" href="#footnote-3">3</a></sup>.
+anonymous inline footnotes are also supported via <sup class="footnote-reference"><a id="footnote-reference-4" href="#footnote-4">4</a></sup>.
 </p>
 </li>
 <li>
 <p>
 Footnote definitions are not printed where they appear.
-Rather, they are gathered and exported at the end of the document in the footnote section. <sup class="footnote-reference"><a id="footnote-reference-4" href="#footnote-4">4</a></sup>
+Rather, they are gathered and exported at the end of the document in the footnote section. <sup class="footnote-reference"><a id="footnote-reference-5" href="#footnote-5">5</a></sup>
 </p>
 </li>
 </ul>
@@ -41,10 +41,10 @@ Rather, they are gathered and exported at the end of the document in the footnot
 Footnotes
 </h1>
 <p>
-Please note that the footnotes section is not automatically excluded from the export like in emacs. <sup class="footnote-reference"><a id="footnote-reference-5" href="#footnote-5">5</a></sup>
+Please note that the footnotes section is not automatically excluded from the export like in emacs. <sup class="footnote-reference"><a id="footnote-reference-6" href="#footnote-6">6</a></sup>
 </p>
 <p>
-this is not part of <sup class="footnote-reference"><a id="footnote-reference-5" href="#footnote-5">5</a></sup> anymore as there are 2 blank lines in between!
+this is not part of <sup class="footnote-reference"><a id="footnote-reference-6" href="#footnote-6">6</a></sup> anymore as there are 2 blank lines in between!
 </p>
 <div class="footnotes">
 <hr class="footnotes-separatator">
@@ -115,7 +115,7 @@ This shouldn&#39;t happen when the definition line and the line after that are e
 <sup id="footnote-2"><a href="#footnote-reference-2">2</a></sup>
 <div class="footnote-body">
 <p>
-the inline footnote definition
+yolo
 </p>
 </div>
 </div>
@@ -123,7 +123,7 @@ the inline footnote definition
 <sup id="footnote-3"><a href="#footnote-reference-3">3</a></sup>
 <div class="footnote-body">
 <p>
-the anonymous inline footnote definition
+the inline footnote definition
 </p>
 </div>
 </div>
@@ -131,13 +131,21 @@ the anonymous inline footnote definition
 <sup id="footnote-4"><a href="#footnote-reference-4">4</a></sup>
 <div class="footnote-body">
 <p>
+the anonymous inline footnote definition
+</p>
+</div>
+</div>
+<div class="footnote-definition">
+<sup id="footnote-5"><a href="#footnote-reference-5">5</a></sup>
+<div class="footnote-body">
+<p>
 so this definition will not be at the end of this section in the exported document.
 Rather, it will be somewhere down below in the footnotes section.
 </p>
 </div>
 </div>
 <div class="footnote-definition">
-<sup id="footnote-5"><a href="#footnote-reference-5">5</a></sup>
+<sup id="footnote-6"><a href="#footnote-reference-6">6</a></sup>
 <div class="footnote-body">
 <p>
 There&#39;s multiple reasons for that. Among others, doing so requires i18n (to recognize the section) and silently

org/testdata/footnotes.org

@@ -1,5 +1,5 @@
 * Using some footnotes
-- normal footnote reference [fn:1] [fn:6]
+- normal footnote reference [fn:1] [fn:6] [fn:foo-bar] (footnote names can be anything in the format =[\w-]=)
 - further references to the same footnote should not [fn:1] render duplicates in the footnote list
 - inline footnotes are also supported via [fn:2:the inline footnote definition].
 - anonymous inline footnotes are also supported via [fn::the anonymous inline footnote definition].
@@ -14,6 +14,8 @@ of the same name later on in the document. That will log a warning but carry on
 * Footnotes
 Please note that the footnotes section is not automatically excluded from the export like in emacs. [fn:7]
 
+[fn:foo-bar] yolo
+
 [fn:1] https://www.example.com
 - footnotes can contain *markup*
 - and other elements

org/testdata/footnotes.pretty_org

@@ -1,5 +1,5 @@
 * Using some footnotes
-- normal footnote reference [fn:1] [fn:6]
+- normal footnote reference [fn:1] [fn:6] [fn:foo-bar] (footnote names can be anything in the format =[\w-]=)
 - further references to the same footnote should not [fn:1] render duplicates in the footnote list
 - inline footnotes are also supported via [fn:2:the inline footnote definition].
 - anonymous inline footnotes are also supported via [fn::the anonymous inline footnote definition].
@@ -14,6 +14,8 @@ of the same name later on in the document. That will log a warning but carry on
 * Footnotes
 Please note that the footnotes section is not automatically excluded from the export like in emacs. [fn:7]
 
+[fn:foo-bar] yolo
+
 [fn:1] https://www.example.com
 - footnotes can contain *markup*
 - and other elements