Deduplicate footnotes

lib/renderer.js

@@ -278,8 +278,12 @@ rules.abbr_close = function (/* tokens, idx, options, env */) {
 
 
 rules.footnote_ref = function (tokens, idx) {
-  var id = Number(tokens[idx].id + 1).toString();
-  return '<a href="#fn' + id + '" class="footnoteRef" id="fnref' + id + '"><sup>' + id + '</sup></a>';
+  var n = Number(tokens[idx].id + 1).toString();
+  var id = 'fnref' + n;
+  if (tokens[idx].subId > 0) {
+    id += ':' + tokens[idx].subId;
+  }
+  return '<a href="#fn' + n + '" class="footnoteRef" id="' + id + '"><sup>' + n + '</sup></a>';
 };
 rules.footnote_block_open = function (tokens, idx, options) {
   return '<div class="footnotes">\n' + (options.xhtmlOut ? '<hr />' : '<hr>') + '\n<ol>\n';
@@ -295,8 +299,12 @@ rules.footnote_close = function () {
   return '</li>\n';
 };
 rules.footnote_anchor = function (tokens, idx) {
-  var id = Number(tokens[idx].id + 1).toString();
-  return '<a href="#fnref' + id + '">↩</a>';
+  var n = Number(tokens[idx].id + 1).toString();
+  var id = 'fnref' + n;
+  if (tokens[idx].subId > 0) {
+    id += ':' + tokens[idx].subId;
+  }
+  return '<a href="#' + id + '">↩</a>';
 };
 
 

lib/rules_block/footnote.js

@@ -28,9 +28,9 @@ module.exports = function footnote(state, startLine, endLine, silent) {
   pos++;
 
   if (!state.env.footnotes) { state.env.footnotes = {}; }
-  if (!state.env.footnotes.available) { state.env.footnotes.available = Object.create(null); }
+  if (!state.env.footnotes.refs) { state.env.footnotes.refs = Object.create(null); }
   label = state.src.slice(start + 2, pos - 2);
-  state.env.footnotes.available[label] = true;
+  state.env.footnotes.refs[label] = -1;
 
   state.tokens.push({
     type: 'footnote_reference_open',

lib/rules_core/footnote_tail.js

@@ -2,7 +2,7 @@
 
 
 module.exports = function footnote_block(state) {
-  var i, l, t, list, tokens, current, currentLabel, anchor,
+  var i, l, j, t, lastParagraph, list, tokens, current, currentLabel,
       level = 0,
       insideRef = false,
       refTokens = Object.create(null);
@@ -61,19 +61,25 @@ module.exports = function footnote_block(state) {
       tokens = refTokens[list[i].label];
     }
 
-    anchor = {
-      type: 'footnote_anchor',
-      id: i,
-      level: level
-    };
-
     state.tokens = state.tokens.concat(tokens);
     if (state.tokens[state.tokens.length - 1].type === 'paragraph_close') {
-      t = state.tokens.pop();
-      state.tokens.push(anchor);
-      state.tokens.push(t);
+      lastParagraph = state.tokens.pop();
     } else {
-      state.tokens.push(anchor);
+      lastParagraph = null;
+    }
+
+    t = list[i].count > 0 ? list[i].count : 1;
+    for (j = 0; j < t; j++) {
+      state.tokens.push({
+        type: 'footnote_anchor',
+        id: i,
+        subId: j,
+        level: level
+      });
+    }
+
+    if (lastParagraph) {
+      state.tokens.push(lastParagraph);
     }
 
     state.tokens.push({

lib/rules_inline/footnote_ref.js

@@ -7,13 +7,14 @@ module.exports = function footnote_ref(state, silent) {
   var label,
       pos,
       footnoteId,
+      footnoteSubId,
       max = state.posMax,
       start = state.pos;
 
   // should be at least 4 chars - "[^x]"
   if (start + 3 > max) { return false; }
 
-  if (!state.env.footnotes || !state.env.footnotes.available) { return false; }
+  if (!state.env.footnotes || !state.env.footnotes.refs) { return false; }
   if (state.src.charCodeAt(start) !== 0x5B/* [ */) { return false; }
   if (state.src.charCodeAt(start + 1) !== 0x5E/* ^ */) { return false; }
   if (state.level >= state.options.maxNesting) { return false; }
@@ -31,19 +32,28 @@ module.exports = function footnote_ref(state, silent) {
   pos++;
 
   label = state.src.slice(start + 2, pos - 1);
-  if (!state.env.footnotes.available[label]) { return false; }
+  if (state.env.footnotes.refs[label] === undefined) { return false; }
 
   if (!silent) {
     if (!state.env.footnotes.list) { state.env.footnotes.list = []; }
-    footnoteId = state.env.footnotes.list.length;
+
+    if (state.env.footnotes.refs[label] < 0) {
+      footnoteId = state.env.footnotes.list.length;
+      state.env.footnotes.list[footnoteId] = { label: label, count: 0 };
+      state.env.footnotes.refs[label] = footnoteId;
+    } else {
+      footnoteId = state.env.footnotes.refs[label];
+    }
+
+    footnoteSubId = state.env.footnotes.list[footnoteId].count;
+    state.env.footnotes.list[footnoteId].count++;
 
     state.push({
       type: 'footnote_ref',
       id: footnoteId,
+      subId: footnoteSubId,
       level: state.level
     });
-
-    state.env.footnotes.list[footnoteId] = { label: label };
   }
 
   state.pos = pos;