Reimplement MD051/link-fragments using micromark tokens, report reference link issues for definition and fix when possible, handle reporting multiple violations on the same line better.

2025-12-16 22:10:13 +01:00 · 2023-08-04 20:53:38 -07:00 · 2023-08-04 20:53:38 -07:00 · ef1bd286a9
commit ef1bd286a9
parent dd73b0ad7f
14 changed files with 458 additions and 346 deletions
--- a/.eslintrc.json
+++ b/.eslintrc.json
@ -223,6 +223,7 @@
    "unicorn/no-new-array": "off",
    "unicorn/no-null": "off",
    "unicorn/no-unsafe-regex": "off",
+    "unicorn/no-useless-undefined": "off",
    "unicorn/prefer-at": "off",
    "unicorn/prefer-module": "off",
    "unicorn/prefer-string-replace-all": "off",
--- a/demo/markdownlint-browser.js
+++ b/demo/markdownlint-browser.js
@ -60,10 +60,6 @@ var inlineCommentStartRe =
 /(<!--\s*markdownlint-(disable|enable|capture|restore|disable-file|enable-file|disable-line|disable-next-line|configure-file))(?:\s|-->)/gi;
 module.exports.inlineCommentStartRe = inlineCommentStartRe;

-// Regular expression for matching HTML elements
-var htmlElementRe = /<(([A-Za-z][A-Za-z\d-]*)(?:\s[^`>]*)?)\/?>/g;
-module.exports.htmlElementRe = htmlElementRe;
-
 // Regular expressions for range matching
 module.exports.listItemMarkerRe = /^([\s>]*)(?:[*+-]|\d+[.)])\s+/;
 module.exports.orderedListItemMarkerRe = /^[\s>]*0*(\d+)[.)]/;
@ -495,42 +491,14 @@ module.exports.flattenLists = function flattenLists(tokens) {
  return flattenedLists;
 };

-/**
- * Calls the provided function for each specified inline child token.
- *
- * @param {Object} params RuleParams instance.
- * @param {string} type Token type identifier.
- * @param {Function} handler Callback function.
- * @returns {void}
- */
-function forEachInlineChild(params, type, handler) {
-  filterTokens(params, "inline", function (token) {
-    var _iterator4 = _createForOfIteratorHelper(token.children.filter(function (c) {
-        return c.type === type;
-      })),
-      _step4;
-    try {
-      for (_iterator4.s(); !(_step4 = _iterator4.n()).done;) {
-        var child = _step4.value;
-        handler(child, token);
-      }
-    } catch (err) {
-      _iterator4.e(err);
-    } finally {
-      _iterator4.f();
-    }
-  });
-}
-module.exports.forEachInlineChild = forEachInlineChild;
-
 // Calls the provided function for each heading's content
 module.exports.forEachHeading = function forEachHeading(params, handler) {
  var heading = null;
-  var _iterator5 = _createForOfIteratorHelper(params.parsers.markdownit.tokens),
-    _step5;
+  var _iterator4 = _createForOfIteratorHelper(params.parsers.markdownit.tokens),
+    _step4;
  try {
-    for (_iterator5.s(); !(_step5 = _iterator5.n()).done;) {
-      var token = _step5.value;
+    for (_iterator4.s(); !(_step4 = _iterator4.n()).done;) {
+      var token = _step4.value;
      if (token.type === "heading_open") {
        heading = token;
      } else if (token.type === "heading_close") {
@ -540,9 +508,9 @@ module.exports.forEachHeading = function forEachHeading(params, handler) {
      }
    }
  } catch (err) {
-    _iterator5.e(err);
+    _iterator4.e(err);
  } finally {
-    _iterator5.f();
+    _iterator4.f();
  }
 };

@ -677,19 +645,19 @@ module.exports.codeBlockAndSpanRanges = function (params, lineMetadata) {
      var tokenLines = params.lines.slice(token.map[0], token.map[1]);
      forEachInlineCodeSpan(tokenLines.join("\n"), function (code, lineIndex, columnIndex) {
        var codeLines = code.split(newLineRe);
-        var _iterator6 = _createForOfIteratorHelper(codeLines.entries()),
-          _step6;
+        var _iterator5 = _createForOfIteratorHelper(codeLines.entries()),
+          _step5;
        try {
-          for (_iterator6.s(); !(_step6 = _iterator6.n()).done;) {
-            var _step6$value = _slicedToArray(_step6.value, 2),
-              i = _step6$value[0],
-              line = _step6$value[1];
+          for (_iterator5.s(); !(_step5 = _iterator5.n()).done;) {
+            var _step5$value = _slicedToArray(_step5.value, 2),
+              i = _step5$value[0],
+              line = _step5$value[1];
            exclusions.push([token.lineNumber - 1 + lineIndex + i, i ? 0 : columnIndex, line.length]);
          }
        } catch (err) {
-          _iterator6.e(err);
+          _iterator5.e(err);
        } finally {
-          _iterator6.f();
+          _iterator5.f();
        }
      });
    }
@ -756,11 +724,11 @@ function getReferenceLinkImageData(params) {
  "definitionLabelString", "gfmFootnoteDefinitionLabelString",
  // references and shortcuts
  "gfmFootnoteCall", "image", "link"]);
-  var _iterator7 = _createForOfIteratorHelper(filteredTokens),
-    _step7;
+  var _iterator6 = _createForOfIteratorHelper(filteredTokens),
+    _step6;
  try {
-    for (_iterator7.s(); !(_step7 = _iterator7.n()).done;) {
-      var token = _step7.value;
+    for (_iterator6.s(); !(_step6 = _iterator6.n()).done;) {
+      var token = _step6.value;
      var labelPrefix = "";
      // eslint-disable-next-line default-case
      switch (token.type) {
@ -827,9 +795,9 @@ function getReferenceLinkImageData(params) {
      }
    }
  } catch (err) {
-    _iterator7.e(err);
+    _iterator6.e(err);
  } finally {
-    _iterator7.f();
+    _iterator6.f();
  }
  return {
    references: references,
@ -853,11 +821,11 @@ function getPreferredLineEnding(input, os) {
  var lf = 0;
  var crlf = 0;
  var endings = input.match(newLineRe) || [];
-  var _iterator8 = _createForOfIteratorHelper(endings),
-    _step8;
+  var _iterator7 = _createForOfIteratorHelper(endings),
+    _step7;
  try {
-    for (_iterator8.s(); !(_step8 = _iterator8.n()).done;) {
-      var ending = _step8.value;
+    for (_iterator7.s(); !(_step7 = _iterator7.n()).done;) {
+      var ending = _step7.value;
      // eslint-disable-next-line default-case
      switch (ending) {
        case "\r":
@ -872,9 +840,9 @@ function getPreferredLineEnding(input, os) {
      }
    }
  } catch (err) {
-    _iterator8.e(err);
+    _iterator7.e(err);
  } finally {
-    _iterator8.f();
+    _iterator7.f();
  }
  var preferredLineEnding = null;
  if (!cr && !lf && !crlf) {
@ -957,11 +925,11 @@ function applyFixes(input, errors) {
  lastFixInfo = {
    "lineNumber": -1
  };
-  var _iterator9 = _createForOfIteratorHelper(fixInfos),
-    _step9;
+  var _iterator8 = _createForOfIteratorHelper(fixInfos),
+    _step8;
  try {
-    for (_iterator9.s(); !(_step9 = _iterator9.n()).done;) {
-      var fixInfo = _step9.value;
+    for (_iterator8.s(); !(_step8 = _iterator8.n()).done;) {
+      var fixInfo = _step8.value;
      if (fixInfo.lineNumber === lastFixInfo.lineNumber && fixInfo.editColumn === lastFixInfo.editColumn && !fixInfo.insertText && fixInfo.deleteCount > 0 && lastFixInfo.insertText && !lastFixInfo.deleteCount) {
        fixInfo.insertText = lastFixInfo.insertText;
        lastFixInfo.lineNumber = 0;
@ -969,9 +937,9 @@ function applyFixes(input, errors) {
      lastFixInfo = fixInfo;
    }
  } catch (err) {
-    _iterator9.e(err);
+    _iterator8.e(err);
  } finally {
-    _iterator9.f();
+    _iterator8.f();
  }
  fixInfos = fixInfos.filter(function (fixInfo) {
    return fixInfo.lineNumber;
@ -979,11 +947,11 @@ function applyFixes(input, errors) {
  // Apply all (remaining/updated) fixes
  var lastLineIndex = -1;
  var lastEditIndex = -1;
-  var _iterator10 = _createForOfIteratorHelper(fixInfos),
-    _step10;
+  var _iterator9 = _createForOfIteratorHelper(fixInfos),
+    _step9;
  try {
-    for (_iterator10.s(); !(_step10 = _iterator10.n()).done;) {
-      var _fixInfo = _step10.value;
+    for (_iterator9.s(); !(_step9 = _iterator9.n()).done;) {
+      var _fixInfo = _step9.value;
      var lineNumber = _fixInfo.lineNumber,
        editColumn = _fixInfo.editColumn,
        deleteCount = _fixInfo.deleteCount;
@ -998,9 +966,9 @@ function applyFixes(input, errors) {
    }
    // Return corrected input
  } catch (err) {
-    _iterator10.e(err);
+    _iterator9.e(err);
  } finally {
-    _iterator10.f();
+    _iterator9.f();
  }
  return lines.filter(function (line) {
    return line !== null;
@ -1348,6 +1316,39 @@ function filterByTypes(tokens, allowed) {
  });
 }

+/**
+ * Filter a list of Micromark tokens for HTML tokens.
+ *
+ * @param {Token[]} tokens Micromark tokens.
+ * @returns {Token[]} Filtered tokens.
+ */
+function filterByHtmlTokens(tokens) {
+  var result = [];
+  var pending = [tokens];
+  var current = null;
+  while (current = pending.shift()) {
+    var _iterator2 = _createForOfIteratorHelper(filterByTypes(current, ["htmlFlow", "htmlText"])),
+      _step2;
+    try {
+      for (_iterator2.s(); !(_step2 = _iterator2.n()).done;) {
+        var token = _step2.value;
+        if (token.type === "htmlText") {
+          result.push(token);
+        } else {
+          // token.type === "htmlFlow"
+          // @ts-ignore
+          pending.push(token.htmlFlowChildren);
+        }
+      }
+    } catch (err) {
+      _iterator2.e(err);
+    } finally {
+      _iterator2.f();
+    }
+  }
+  return result;
+}
+
 /**
 * Returns a list of all nested child tokens.
 *
@ -1438,6 +1439,7 @@ function tokenIfType(token, type) {
 }
 module.exports = {
  "parse": micromarkParse,
+  filterByHtmlTokens: filterByHtmlTokens,
  filterByPredicate: filterByPredicate,
  filterByTypes: filterByTypes,
  flattenedChildren: flattenedChildren,
@ -4855,7 +4857,7 @@ function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len
 var _require = __webpack_require__(/*! ../helpers */ "../helpers/helpers.js"),
  addError = _require.addError;
 var _require2 = __webpack_require__(/*! ../helpers/micromark.cjs */ "../helpers/micromark.cjs"),
-  filterByTypes = _require2.filterByTypes,
+  filterByHtmlTokens = _require2.filterByHtmlTokens,
  getHtmlTagInfo = _require2.getHtmlTagInfo;
 var nextLinesRe = /[\r\n][\s\S]*$/;
 module.exports = {
@ -4868,31 +4870,21 @@ module.exports = {
    allowedElements = allowedElements.map(function (element) {
      return element.toLowerCase();
    });
-    var pending = [params.parsers.micromark.tokens];
-    var current = null;
-    while (current = pending.shift()) {
-      var tokens = current;
-      var _iterator = _createForOfIteratorHelper(filterByTypes(tokens, ["htmlFlow", "htmlText"])),
-        _step;
-      try {
-        for (_iterator.s(); !(_step = _iterator.n()).done;) {
-          var token = _step.value;
-          if (token.type === "htmlText") {
-            var htmlTagInfo = getHtmlTagInfo(token);
-            if (htmlTagInfo && !htmlTagInfo.close && !allowedElements.includes(htmlTagInfo.name.toLowerCase())) {
-              var range = [token.startColumn, token.text.replace(nextLinesRe, "").length];
-              addError(onError, token.startLine, "Element: " + htmlTagInfo.name, undefined, range);
-            }
-          } else {
-            // token.type === "htmlFlow"
-            pending.push(token.htmlFlowChildren);
-          }
+    var _iterator = _createForOfIteratorHelper(filterByHtmlTokens(params.parsers.micromark.tokens)),
+      _step;
+    try {
+      for (_iterator.s(); !(_step = _iterator.n()).done;) {
+        var token = _step.value;
+        var htmlTagInfo = getHtmlTagInfo(token);
+        if (htmlTagInfo && !htmlTagInfo.close && !allowedElements.includes(htmlTagInfo.name.toLowerCase())) {
+          var range = [token.startColumn, token.text.replace(nextLinesRe, "").length];
+          addError(onError, token.startLine, "Element: " + htmlTagInfo.name, undefined, range);
        }
-      } catch (err) {
-        _iterator.e(err);
-      } finally {
-        _iterator.f();
      }
+    } catch (err) {
+      _iterator.e(err);
+    } finally {
+      _iterator.f();
    }
  }
 };
@ -6098,18 +6090,18 @@ function _iterableToArray(iter) { if (typeof Symbol !== "undefined" && iter[Symb
 function _arrayWithoutHoles(arr) { if (Array.isArray(arr)) return _arrayLikeToArray(arr); }
 function _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _unsupportedIterableToArray(arr, i) || _nonIterableRest(); }
 function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
-function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
-function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) arr2[i] = arr[i]; return arr2; }
 function _iterableToArrayLimit(arr, i) { var _i = null == arr ? null : "undefined" != typeof Symbol && arr[Symbol.iterator] || arr["@@iterator"]; if (null != _i) { var _s, _e, _x, _r, _arr = [], _n = !0, _d = !1; try { if (_x = (_i = _i.call(arr)).next, 0 === i) { if (Object(_i) !== _i) return; _n = !1; } else for (; !(_n = (_s = _x.call(_i)).done) && (_arr.push(_s.value), _arr.length !== i); _n = !0); } catch (err) { _d = !0, _e = err; } finally { try { if (!_n && null != _i["return"] && (_r = _i["return"](), Object(_r) !== _r)) return; } finally { if (_d) throw _e; } } return _arr; } }
 function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }
+function _createForOfIteratorHelper(o, allowArrayLike) { var it = typeof Symbol !== "undefined" && o[Symbol.iterator] || o["@@iterator"]; if (!it) { if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") { if (it) o = it; var i = 0; var F = function F() {}; return { s: F, n: function n() { if (i >= o.length) return { done: true }; return { done: false, value: o[i++] }; }, e: function e(_e2) { throw _e2; }, f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } var normalCompletion = true, didErr = false, err; return { s: function s() { it = it.call(o); }, n: function n() { var step = it.next(); normalCompletion = step.done; return step; }, e: function e(_e3) { didErr = true; err = _e3; }, f: function f() { try { if (!normalCompletion && it["return"] != null) it["return"](); } finally { if (didErr) throw err; } } }; }
+function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
+function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) arr2[i] = arr[i]; return arr2; }
 var _require = __webpack_require__(/*! ../helpers */ "../helpers/helpers.js"),
  addError = _require.addError,
-  addErrorDetailIf = _require.addErrorDetailIf,
-  escapeForRegExp = _require.escapeForRegExp,
-  filterTokens = _require.filterTokens,
-  forEachInlineChild = _require.forEachInlineChild,
-  forEachHeading = _require.forEachHeading,
-  htmlElementRe = _require.htmlElementRe;
+  addErrorDetailIf = _require.addErrorDetailIf;
+var _require2 = __webpack_require__(/*! ../helpers/micromark.cjs */ "../helpers/micromark.cjs"),
+  filterByHtmlTokens = _require2.filterByHtmlTokens,
+  filterByTypes = _require2.filterByTypes,
+  getHtmlTagInfo = _require2.getHtmlTagInfo;

 // Regular expression for identifying HTML anchor names
 var idRe = /[\t-\r \xA0\u1680\u2000-\u200A\u2028\u2029\u202F\u205F\u3000\uFEFF]id[\t-\r \xA0\u1680\u2000-\u200A\u2028\u2029\u202F\u205F\u3000\uFEFF]*=[\t-\r \xA0\u1680\u2000-\u200A\u2028\u2029\u202F\u205F\u3000\uFEFF]*["']?((?:(?![\t-\r "'>\xA0\u1680\u2000-\u200A\u2028\u2029\u202F\u205F\u3000\uD800-\uDFFF\uFEFF])[\s\S]|[\uD800-\uDBFF][\uDC00-\uDFFF])+)/i;
@ -6120,14 +6112,12 @@ var anchorRe = /\{(#[0-9a-z]+(?:[\x2D_][0-9a-z]+)*)\}/g;
 * Converts a Markdown heading into an HTML fragment according to the rules
 * used by GitHub.
 *
- * @param {Object} inline Inline token for heading.
+ * @param {Object} headingText Heading text token.
 * @returns {string} Fragment string for heading.
 */
-function convertHeadingToHTMLFragment(inline) {
-  var inlineText = inline.children.filter(function (token) {
-    return token.type !== "html_inline";
-  }).map(function (token) {
-    return token.content;
+function convertHeadingToHTMLFragment(headingText) {
+  var inlineText = filterByTypes(headingText.children, ["codeTextData", "data"]).map(function (token) {
+    return token.text;
  }).join("");
  return "#" + encodeURIComponent(inlineText.toLowerCase()
  // RegExp source with Ruby's \p{Word} expanded into its General Categories
@ -6141,81 +6131,116 @@ module.exports = {
  "description": "Link fragments should be valid",
  "tags": ["links"],
  "function": function MD051(params, onError) {
+    var tokens = params.parsers.micromark.tokens;
    var fragments = new Map();
+
    // Process headings
-    forEachHeading(params, function (heading, content, inline) {
-      var fragment = convertHeadingToHTMLFragment(inline);
-      var count = fragments.get(fragment) || 0;
-      if (count) {
-        fragments.set("".concat(fragment, "-").concat(count), 0);
-      }
-      fragments.set(fragment, count + 1);
-      var match = null;
-      while ((match = anchorRe.exec(content)) !== null) {
-        var _match = match,
-          _match2 = _slicedToArray(_match, 2),
-          anchor = _match2[1];
-        if (!fragments.has(anchor)) {
-          fragments.set(anchor, 1);
+    var headingTexts = filterByTypes(tokens, ["atxHeadingText", "setextHeadingText"]);
+    var _iterator = _createForOfIteratorHelper(headingTexts),
+      _step;
+    try {
+      for (_iterator.s(); !(_step = _iterator.n()).done;) {
+        var headingText = _step.value;
+        var fragment = convertHeadingToHTMLFragment(headingText);
+        var count = fragments.get(fragment) || 0;
+        if (count) {
+          fragments.set("".concat(fragment, "-").concat(count), 0);
+        }
+        fragments.set(fragment, count + 1);
+        var match = null;
+        while ((match = anchorRe.exec(headingText.text)) !== null) {
+          var _match = match,
+            _match2 = _slicedToArray(_match, 2),
+            anchor = _match2[1];
+          if (!fragments.has(anchor)) {
+            fragments.set(anchor, 1);
+          }
        }
      }
-    });
-    // Process HTML anchors
-    var processHtmlToken = function processHtmlToken(token) {
-      var match = null;
-      while ((match = htmlElementRe.exec(token.content)) !== null) {
-        var _match3 = match,
-          _match4 = _slicedToArray(_match3, 3),
-          tag = _match4[0],
-          element = _match4[2];
-        var anchorMatch = idRe.exec(tag) || element.toLowerCase() === "a" && nameRe.exec(tag);
-        if (anchorMatch) {
-          fragments.set("#".concat(anchorMatch[1]), 0);
+
+      // Process HTML anchors
+    } catch (err) {
+      _iterator.e(err);
+    } finally {
+      _iterator.f();
+    }
+    var _iterator2 = _createForOfIteratorHelper(filterByHtmlTokens(tokens)),
+      _step2;
+    try {
+      for (_iterator2.s(); !(_step2 = _iterator2.n()).done;) {
+        var token = _step2.value;
+        var htmlTagInfo = getHtmlTagInfo(token);
+        if (htmlTagInfo && !htmlTagInfo.close) {
+          var anchorMatch = idRe.exec(token.text) || htmlTagInfo.name.toLowerCase() === "a" && nameRe.exec(token.text);
+          if (anchorMatch) {
+            fragments.set("#".concat(anchorMatch[1]), 0);
+          }
        }
      }
-    };
-    filterTokens(params, "html_block", processHtmlToken);
-    forEachInlineChild(params, "html_inline", processHtmlToken);
-    // Process link fragments
-    forEachInlineChild(params, "link_open", function (token) {
-      var attrs = token.attrs,
-        lineNumber = token.lineNumber,
-        line = token.line;
-      var href = attrs.find(function (attr) {
-        return attr[0] === "href";
-      });
-      var id = href && href[1];
-      if (id && id.length > 1 && id[0] === "#" && !fragments.has(id)) {
-        var context = id;
-        var range = null;
-        var fixInfo = null;
-        var match = line.match(new RegExp("\\[.*?\\]\\(".concat(escapeForRegExp(context), "\\)")));
-        if (match) {
-          var _match5 = _slicedToArray(match, 1);
-          context = _match5[0];
-          var index = match.index;
-          var length = context.length;
-          range = [index + 1, length];
-          fixInfo = {
-            "editColumn": index + (length - id.length),
-            "deleteCount": id.length,
-            "insertText": null
-          };
-        }
-        var idLower = id.toLowerCase();
-        var mixedCaseKey = _toConsumableArray(fragments.keys()).find(function (key) {
-          return idLower === key.toLowerCase();
-        });
-        if (mixedCaseKey) {
-          (fixInfo || {}).insertText = mixedCaseKey;
-          addErrorDetailIf(onError, lineNumber, mixedCaseKey, id, undefined, context, range, fixInfo);
-        } else {
-          addError(onError, lineNumber, undefined, context,
-          // @ts-ignore
-          range);
+
+      // Process link and definition fragments
+    } catch (err) {
+      _iterator2.e(err);
+    } finally {
+      _iterator2.f();
+    }
+    var parentChilds = [["link", "resourceDestinationString"], ["definition", "definitionDestinationString"]];
+    for (var _i = 0, _parentChilds = parentChilds; _i < _parentChilds.length; _i++) {
+      var _parentChilds$_i = _slicedToArray(_parentChilds[_i], 2),
+        parentType = _parentChilds$_i[0],
+        definitionType = _parentChilds$_i[1];
+      var links = filterByTypes(tokens, [parentType]);
+      var _iterator3 = _createForOfIteratorHelper(links),
+        _step3;
+      try {
+        for (_iterator3.s(); !(_step3 = _iterator3.n()).done;) {
+          var link = _step3.value;
+          var definitions = filterByTypes(link.children, [definitionType]);
+          var _iterator4 = _createForOfIteratorHelper(definitions),
+            _step4;
+          try {
+            var _loop = function _loop() {
+              var definition = _step4.value;
+              if (definition.text.length > 1 && definition.text.startsWith("#") && !fragments.has(definition.text)) {
+                // eslint-disable-next-line no-undef-init
+                var range = undefined;
+                // eslint-disable-next-line no-undef-init
+                var fixInfo = undefined;
+                if (link.startLine === link.endLine) {
+                  range = [link.startColumn, link.endColumn - link.startColumn];
+                  fixInfo = {
+                    "editColumn": definition.startColumn,
+                    "deleteCount": definition.endColumn - definition.startColumn
+                  };
+                }
+                var definitionTextLower = definition.text.toLowerCase();
+                var mixedCaseKey = _toConsumableArray(fragments.keys()).find(function (key) {
+                  return definitionTextLower === key.toLowerCase();
+                });
+                if (mixedCaseKey) {
+                  // @ts-ignore
+                  (fixInfo || {}).insertText = mixedCaseKey;
+                  addErrorDetailIf(onError, link.startLine, mixedCaseKey, definition.text, undefined, link.text, range, fixInfo);
+                } else {
+                  addError(onError, link.startLine, undefined, link.text, range);
+                }
+              }
+            };
+            for (_iterator4.s(); !(_step4 = _iterator4.n()).done;) {
+              _loop();
+            }
+          } catch (err) {
+            _iterator4.e(err);
+          } finally {
+            _iterator4.f();
+          }
        }
+      } catch (err) {
+        _iterator3.e(err);
+      } finally {
+        _iterator3.f();
      }
-    });
+    }
  }
 };

--- a/doc-build/md051.md
+++ b/doc-build/md051.md
@ -26,8 +26,8 @@ letters, numbers, `-`, and `_`):
 [Link](#custom-name)
 ```

-Alternatively, an HTML `a` tag with an `id` or a `name` attribute can be used to
-define a fragment:
+Alternatively, any HTML tag with an `id` attribute or an `a` tag with a `name`
+attribute can be used to define a fragment:

 ```markdown
 <a id="bookmark"></a>
--- a/doc/Rules.md
+++ b/doc/Rules.md
@ -2176,8 +2176,8 @@ letters, numbers, `-`, and `_`):
 [Link](#custom-name)
 ```

-Alternatively, an HTML `a` tag with an `id` or a `name` attribute can be used to
-define a fragment:
+Alternatively, any HTML tag with an `id` attribute or an `a` tag with a `name`
+attribute can be used to define a fragment:

 ```markdown
 <a id="bookmark"></a>
--- a/doc/md051.md
+++ b/doc/md051.md
@ -34,8 +34,8 @@ letters, numbers, `-`, and `_`):
 [Link](#custom-name)
 ```

-Alternatively, an HTML `a` tag with an `id` or a `name` attribute can be used to
-define a fragment:
+Alternatively, any HTML tag with an `id` attribute or an `a` tag with a `name`
+attribute can be used to define a fragment:

 ```markdown
 <a id="bookmark"></a>
--- a/helpers/helpers.js
+++ b/helpers/helpers.js
@ -18,10 +18,6 @@ const inlineCommentStartRe =
  /(<!--\s*markdownlint-(disable|enable|capture|restore|disable-file|enable-file|disable-line|disable-next-line|configure-file))(?:\s|-->)/gi;
 module.exports.inlineCommentStartRe = inlineCommentStartRe;

-// Regular expression for matching HTML elements
-const htmlElementRe = /<(([A-Za-z][A-Za-z\d-]*)(?:\s[^`>]*)?)\/?>/g;
-module.exports.htmlElementRe = htmlElementRe;
-
 // Regular expressions for range matching
 module.exports.listItemMarkerRe = /^([\s>]*)(?:[*+-]|\d+[.)])\s+/;
 module.exports.orderedListItemMarkerRe = /^[\s>]*0*(\d+)[.)]/;
@ -444,23 +440,6 @@ module.exports.flattenLists = function flattenLists(tokens) {
  return flattenedLists;
 };

-/**
- * Calls the provided function for each specified inline child token.
- *
- * @param {Object} params RuleParams instance.
- * @param {string} type Token type identifier.
- * @param {Function} handler Callback function.
- * @returns {void}
- */
-function forEachInlineChild(params, type, handler) {
-  filterTokens(params, "inline", (token) => {
-    for (const child of token.children.filter((c) => c.type === type)) {
-      handler(child, token);
-    }
-  });
-}
-module.exports.forEachInlineChild = forEachInlineChild;
-
 // Calls the provided function for each heading's content
 module.exports.forEachHeading = function forEachHeading(params, handler) {
  let heading = null;
--- a/helpers/micromark.cjs
+++ b/helpers/micromark.cjs
@ -204,6 +204,30 @@ function filterByTypes(tokens, allowed) {
  );
 }

+/**
+ * Filter a list of Micromark tokens for HTML tokens.
+ *
+ * @param {Token[]} tokens Micromark tokens.
+ * @returns {Token[]} Filtered tokens.
+ */
+function filterByHtmlTokens(tokens) {
+  const result = [];
+  const pending = [ tokens ];
+  let current = null;
+  while ((current = pending.shift())) {
+    for (const token of filterByTypes(current, [ "htmlFlow", "htmlText" ])) {
+      if (token.type === "htmlText") {
+        result.push(token);
+      } else {
+        // token.type === "htmlFlow"
+        // @ts-ignore
+        pending.push(token.htmlFlowChildren);
+      }
+    }
+  }
+  return result;
+}
+
 /**
 * Returns a list of all nested child tokens.
 *
@ -293,6 +317,7 @@ function tokenIfType(token, type) {

 module.exports = {
  "parse": micromarkParse,
+  filterByHtmlTokens,
  filterByPredicate,
  filterByTypes,
  flattenedChildren,
--- a/lib/md033.js
+++ b/lib/md033.js
@ -3,7 +3,8 @@
 "use strict";

 const { addError } = require("../helpers");
-const { filterByTypes, getHtmlTagInfo } = require("../helpers/micromark.cjs");
+const { filterByHtmlTokens, getHtmlTagInfo } =
+  require("../helpers/micromark.cjs");

 const nextLinesRe = /[\r\n][\s\S]*$/;

@ -15,34 +16,24 @@ module.exports = {
    let allowedElements = params.config.allowed_elements;
    allowedElements = Array.isArray(allowedElements) ? allowedElements : [];
    allowedElements = allowedElements.map((element) => element.toLowerCase());
-    const pending = [ params.parsers.micromark.tokens ];
-    let current = null;
-    while ((current = pending.shift())) {
-      const tokens = current;
-      for (const token of filterByTypes(tokens, [ "htmlFlow", "htmlText" ])) {
-        if (token.type === "htmlText") {
-          const htmlTagInfo = getHtmlTagInfo(token);
-          if (
-            htmlTagInfo &&
-            !htmlTagInfo.close &&
-            !allowedElements.includes(htmlTagInfo.name.toLowerCase())
-          ) {
-            const range = [
-              token.startColumn,
-              token.text.replace(nextLinesRe, "").length
-            ];
-            addError(
-              onError,
-              token.startLine,
-              "Element: " + htmlTagInfo.name,
-              undefined,
-              range
-            );
-          }
-        } else {
-          // token.type === "htmlFlow"
-          pending.push(token.htmlFlowChildren);
-        }
+    for (const token of filterByHtmlTokens(params.parsers.micromark.tokens)) {
+      const htmlTagInfo = getHtmlTagInfo(token);
+      if (
+        htmlTagInfo &&
+        !htmlTagInfo.close &&
+        !allowedElements.includes(htmlTagInfo.name.toLowerCase())
+      ) {
+        const range = [
+          token.startColumn,
+          token.text.replace(nextLinesRe, "").length
+        ];
+        addError(
+          onError,
+          token.startLine,
+          "Element: " + htmlTagInfo.name,
+          undefined,
+          range
+        );
      }
    }
  }
--- a/lib/md051.js
+++ b/lib/md051.js
@ -2,8 +2,9 @@

 "use strict";

-const { addError, addErrorDetailIf, escapeForRegExp, filterTokens,
-  forEachInlineChild, forEachHeading, htmlElementRe } = require("../helpers");
+const { addError, addErrorDetailIf } = require("../helpers");
+const { filterByHtmlTokens, filterByTypes, getHtmlTagInfo } =
+  require("../helpers/micromark.cjs");

 // Regular expression for identifying HTML anchor names
 const idRe = /\sid\s*=\s*['"]?([^'"\s>]+)/iu;
@ -14,14 +15,14 @@ const anchorRe = /\{(#[a-z\d]+(?:[-_][a-z\d]+)*)\}/gu;
 * Converts a Markdown heading into an HTML fragment according to the rules
 * used by GitHub.
 *
- * @param {Object} inline Inline token for heading.
+ * @param {Object} headingText Heading text token.
 * @returns {string} Fragment string for heading.
 */
-function convertHeadingToHTMLFragment(inline) {
-  const inlineText = inline.children
-    .filter((token) => token.type !== "html_inline")
-    .map((token) => token.content)
-    .join("");
+function convertHeadingToHTMLFragment(headingText) {
+  const inlineText =
+    filterByTypes(headingText.children, [ "codeTextData", "data" ])
+      .map((token) => token.text)
+      .join("");
  return "#" + encodeURIComponent(
    inlineText
      .toLowerCase()
@ -42,86 +43,96 @@ module.exports = {
  "description": "Link fragments should be valid",
  "tags": [ "links" ],
  "function": function MD051(params, onError) {
+    const { tokens } = params.parsers.micromark;
    const fragments = new Map();
+
    // Process headings
-    forEachHeading(params, (heading, content, inline) => {
-      const fragment = convertHeadingToHTMLFragment(inline);
+    const headingTexts = filterByTypes(
+      tokens,
+      [ "atxHeadingText", "setextHeadingText" ]
+    );
+    for (const headingText of headingTexts) {
+      const fragment = convertHeadingToHTMLFragment(headingText);
      const count = fragments.get(fragment) || 0;
      if (count) {
        fragments.set(`${fragment}-${count}`, 0);
      }
      fragments.set(fragment, count + 1);
      let match = null;
-      while ((match = anchorRe.exec(content)) !== null) {
+      while ((match = anchorRe.exec(headingText.text)) !== null) {
        const [ , anchor ] = match;
        if (!fragments.has(anchor)) {
          fragments.set(anchor, 1);
        }
      }
-    });
+    }
+
    // Process HTML anchors
-    const processHtmlToken = (token) => {
-      let match = null;
-      while ((match = htmlElementRe.exec(token.content)) !== null) {
-        const [ tag, , element ] = match;
-        const anchorMatch = idRe.exec(tag) ||
-            (element.toLowerCase() === "a" && nameRe.exec(tag));
+    for (const token of filterByHtmlTokens(tokens)) {
+      const htmlTagInfo = getHtmlTagInfo(token);
+      if (htmlTagInfo && !htmlTagInfo.close) {
+        const anchorMatch = idRe.exec(token.text) ||
+          (htmlTagInfo.name.toLowerCase() === "a" && nameRe.exec(token.text));
        if (anchorMatch) {
          fragments.set(`#${anchorMatch[1]}`, 0);
        }
      }
-    };
-    filterTokens(params, "html_block", processHtmlToken);
-    forEachInlineChild(params, "html_inline", processHtmlToken);
-    // Process link fragments
-    forEachInlineChild(params, "link_open", (token) => {
-      const { attrs, lineNumber, line } = token;
-      const href = attrs.find((attr) => attr[0] === "href");
-      const id = href && href[1];
-      if (id && (id.length > 1) && (id[0] === "#") && !fragments.has(id)) {
-        let context = id;
-        let range = null;
-        let fixInfo = null;
-        const match = line.match(
-          new RegExp(`\\[.*?\\]\\(${escapeForRegExp(context)}\\)`)
-        );
-        if (match) {
-          [ context ] = match;
-          const index = match.index;
-          const length = context.length;
-          range = [ index + 1, length ];
-          fixInfo = {
-            "editColumn": index + (length - id.length),
-            "deleteCount": id.length,
-            "insertText": null
-          };
-        }
-        const idLower = id.toLowerCase();
-        const mixedCaseKey = [ ...fragments.keys() ]
-          .find((key) => idLower === key.toLowerCase());
-        if (mixedCaseKey) {
-          (fixInfo || {}).insertText = mixedCaseKey;
-          addErrorDetailIf(
-            onError,
-            lineNumber,
-            mixedCaseKey,
-            id,
-            undefined,
-            context,
-            range,
-            fixInfo
-          );
-        } else {
-          addError(
-            onError,
-            lineNumber,
-            undefined,
-            context,
-            // @ts-ignore
-            range
-          );
+    }
+
+    // Process link and definition fragments
+    const parentChilds = [
+      [ "link", "resourceDestinationString" ],
+      [ "definition", "definitionDestinationString" ]
+    ];
+    for (const [ parentType, definitionType ] of parentChilds) {
+      const links = filterByTypes(tokens, [ parentType ]);
+      for (const link of links) {
+        const definitions = filterByTypes(link.children, [ definitionType ]);
+        for (const definition of definitions) {
+          if (
+            (definition.text.length > 1) &&
+            definition.text.startsWith("#") &&
+            !fragments.has(definition.text)
+          ) {
+            // eslint-disable-next-line no-undef-init
+            let range = undefined;
+            // eslint-disable-next-line no-undef-init
+            let fixInfo = undefined;
+            if (link.startLine === link.endLine) {
+              range = [ link.startColumn, link.endColumn - link.startColumn ];
+              fixInfo = {
+                "editColumn": definition.startColumn,
+                "deleteCount": definition.endColumn - definition.startColumn
+              };
+            }
+            const definitionTextLower = definition.text.toLowerCase();
+            const mixedCaseKey = [ ...fragments.keys() ]
+              .find((key) => definitionTextLower === key.toLowerCase());
+            if (mixedCaseKey) {
+              // @ts-ignore
+              (fixInfo || {}).insertText = mixedCaseKey;
+              addErrorDetailIf(
+                onError,
+                link.startLine,
+                mixedCaseKey,
+                definition.text,
+                undefined,
+                link.text,
+                range,
+                fixInfo
+              );
+            } else {
+              addError(
+                onError,
+                link.startLine,
+                undefined,
+                link.text,
+                range
+              );
+            }
+          }
        }
      }
-    });
+    }
  }
 };
--- a/test/link-fragments.md
+++ b/test/link-fragments.md
@ -12,6 +12,8 @@

 [Valid](#valid-heading-with-emphasis)

+[Valid](#valid-heading-with-code)
+
 [Valid](#valid-heading-with-quotes--and-double-quotes-)

 [Valid](#-valid-heading-with-emoji)
@ -70,6 +72,10 @@ Text

 Text

+### Valid Heading With `Code`
+
+Text
+
 ### Valid Heading With Quotes ' And Double Quotes "

 Text
@ -157,9 +163,12 @@ Text

 [Invalid](#not-an-id-should-be-ignored) {MD051}

-[Invalid][badref] {MD051}
+[Invalid {MD051}](#multi-line
+"Title")

-[badref]: #missing
+[Invalid][badref]
+
+[badref]: #missing "{MD051}"

 ## Inconsistent Case Fragments

@ -167,9 +176,12 @@ Text

 [ALL CAPS](#NAMEDLINK) {MD051}

-[MiXeD][mixedref] {MD051}
+[Multi-line {MD051}](#NAMEDLINK
+"Title")

-[mixedref]: #idLINK
+[MiXeD][mixedref]
+
+[mixedref]: #idLINK "{MD051}"

 ## Valid Named Fragments

--- a/test/snapshots/markdownlint-test-repos.js.md
+++ b/test/snapshots/markdownlint-test-repos.js.md
@ -55,10 +55,10 @@ Generated by [AVA](https://avajs.dev).
 > Expected linting violations

    `test-repos/mochajs-mocha/.github/CODE_OF_CONDUCT.md: 58: MD034/no-bare-urls Bare URL used [Context: "report@lists.openjsf.org"]␊
-    test-repos/mochajs-mocha/.github/CONTRIBUTING.md: 11: MD051/link-fragments Link fragments should be valid [Context: "[search](https://github.com/mochajs/mocha/issues/) to see if it's already been reported**. Otherwise, create a [new issue](https://github.com/mochajs/mocha/issues/new). If you can fix the bug yourself, feel free to create a [pull request](#propose-a-change)"]␊
+    test-repos/mochajs-mocha/.github/CONTRIBUTING.md: 11: MD051/link-fragments Link fragments should be valid [Context: "[pull request](#propose-a-change)"]␊
    test-repos/mochajs-mocha/.github/CONTRIBUTING.md: 41: MD051/link-fragments Link fragments should be valid [Context: "[ask for help](#got-a-question)"]␊
    test-repos/mochajs-mocha/MAINTAINERS.md: 34: MD051/link-fragments Link fragments should be valid [Context: "[Projects](#projects)"]␊
-    test-repos/mochajs-mocha/PROJECT_CHARTER.md: 51: MD051/link-fragments Link fragments should be valid [Context: "[mochajs organization](https://github.com/mochajs) unless explicitly stated in [§2: Scope](#%c2%a72-scope)"]␊
+    test-repos/mochajs-mocha/PROJECT_CHARTER.md: 51: MD051/link-fragments Link fragments should be valid [Context: "[§2: Scope](#%c2%a72-scope)"]␊
    test-repos/mochajs-mocha/PROJECT_CHARTER.md: 56: MD051/link-fragments Link fragments should be valid [Context: "[§2: Scope](#%c2%a72-scope)"]␊
    test-repos/mochajs-mocha/docs/index.md: 32: MD051/link-fragments Link fragments should be valid [Context: "[global variable leak detection](#-check-leaks)"]␊
    test-repos/mochajs-mocha/docs/index.md: 33: MD051/link-fragments Link fragments should be valid [Context: "[optionally run tests that match a regexp](#-grep-regexp-g-regexp)"]␊
@ -72,7 +72,7 @@ Generated by [AVA](https://avajs.dev).
    test-repos/mochajs-mocha/docs/index.md: 1257: MD051/link-fragments Link fragments should be valid [Context: "[\`--node-option\`](#-node-option-name-n-name)"]␊
    test-repos/mochajs-mocha/docs/index.md: 1263: MD051/link-fragments Link fragments should be valid [Context: "[\`--parallel\`](#-parallel-p)"]␊
    test-repos/mochajs-mocha/docs/index.md: 1288: MD051/link-fragments Link fragments should be valid [Context: "[\`--grep\`](#-grep-regexp-g-regexp)"]␊
-    test-repos/mochajs-mocha/docs/index.md: 1288: MD051/link-fragments Link fragments should be valid [Context: "[\`--grep\`](#-grep-regexp-g-regexp) or [\`--fgrep\`](#-fgrep-string-f-string)"]␊
+    test-repos/mochajs-mocha/docs/index.md: 1288: MD051/link-fragments Link fragments should be valid [Context: "[\`--fgrep\`](#-fgrep-string-f-string)"]␊
    test-repos/mochajs-mocha/docs/index.md: 1299: MD051/link-fragments Link fragments should be valid [Context: "[\`--file\`](#-file-filedirectoryglob)"]␊
    test-repos/mochajs-mocha/docs/index.md: 1300: MD051/link-fragments Link fragments should be valid [Context: "[\`--sort\`](#-sort-s)"]␊
    test-repos/mochajs-mocha/docs/index.md: 1306: MD051/link-fragments Link fragments should be valid [Context: "[globally](#-timeout-ms-t-ms)"]␊
--- a/test/snapshots/markdownlint-test-repos.js.snap
+++ b/test/snapshots/markdownlint-test-repos.js.snap
--- a/test/snapshots/markdownlint-test-scenarios.js.md
+++ b/test/snapshots/markdownlint-test-scenarios.js.md
@ -23472,7 +23472,7 @@ Generated by [AVA](https://avajs.dev).
            31,
          ],
          fixInfo: null,
-          lineNumber: 144,
+          lineNumber: 150,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23488,7 +23488,7 @@ Generated by [AVA](https://avajs.dev).
            36,
          ],
          fixInfo: null,
-          lineNumber: 146,
+          lineNumber: 152,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23504,7 +23504,7 @@ Generated by [AVA](https://avajs.dev).
            28,
          ],
          fixInfo: null,
-          lineNumber: 148,
+          lineNumber: 154,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23520,7 +23520,7 @@ Generated by [AVA](https://avajs.dev).
            18,
          ],
          fixInfo: null,
-          lineNumber: 150,
+          lineNumber: 156,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23540,7 +23540,7 @@ Generated by [AVA](https://avajs.dev).
            editColumn: 11,
            insertText: '#HREFandID',
          },
-          lineNumber: 152,
+          lineNumber: 158,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23556,7 +23556,7 @@ Generated by [AVA](https://avajs.dev).
            34,
          ],
          fixInfo: null,
-          lineNumber: 154,
+          lineNumber: 160,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23572,7 +23572,7 @@ Generated by [AVA](https://avajs.dev).
            34,
          ],
          fixInfo: null,
-          lineNumber: 156,
+          lineNumber: 162,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23588,7 +23588,7 @@ Generated by [AVA](https://avajs.dev).
            39,
          ],
          fixInfo: null,
-          lineNumber: 158,
+          lineNumber: 164,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23597,11 +23597,28 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#missing',
+          errorContext: `[Invalid {MD051}](#multi-line␊
+          "Title")`,
          errorDetail: null,
          errorRange: null,
          fixInfo: null,
-          lineNumber: 160,
+          lineNumber: 166,
+          ruleDescription: 'Link fragments should be valid',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
+          ruleNames: [
+            'MD051',
+            'link-fragments',
+          ],
+        },
+        {
+          errorContext: '[badref]: #missing "{MD051}"',
+          errorDetail: null,
+          errorRange: [
+            1,
+            28,
+          ],
+          fixInfo: null,
+          lineNumber: 171,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23621,7 +23638,7 @@ Generated by [AVA](https://avajs.dev).
            editColumn: 9,
            insertText: '#valid-fragments',
          },
-          lineNumber: 166,
+          lineNumber: 175,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23641,7 +23658,7 @@ Generated by [AVA](https://avajs.dev).
            editColumn: 12,
            insertText: '#namedlink',
          },
-          lineNumber: 168,
+          lineNumber: 177,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23650,11 +23667,32 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#idLINK',
-          errorDetail: 'Expected: #idlink; Actual: #idLINK',
+          errorContext: `[Multi-line {MD051}](#NAMEDLINK␊
+          "Title")`,
+          errorDetail: 'Expected: #namedlink; Actual: #NAMEDLINK',
          errorRange: null,
          fixInfo: null,
-          lineNumber: 170,
+          lineNumber: 179,
+          ruleDescription: 'Link fragments should be valid',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
+          ruleNames: [
+            'MD051',
+            'link-fragments',
+          ],
+        },
+        {
+          errorContext: '[mixedref]: #idLINK "{MD051}"',
+          errorDetail: 'Expected: #idlink; Actual: #idLINK',
+          errorRange: [
+            1,
+            29,
+          ],
+          fixInfo: {
+            deleteCount: 7,
+            editColumn: 13,
+            insertText: '#idlink',
+          },
+          lineNumber: 184,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23670,7 +23708,7 @@ Generated by [AVA](https://avajs.dev).
            26,
          ],
          fixInfo: null,
-          lineNumber: 207,
+          lineNumber: 219,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23686,7 +23724,7 @@ Generated by [AVA](https://avajs.dev).
            26,
          ],
          fixInfo: null,
-          lineNumber: 209,
+          lineNumber: 221,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23702,7 +23740,7 @@ Generated by [AVA](https://avajs.dev).
            20,
          ],
          fixInfo: null,
-          lineNumber: 211,
+          lineNumber: 223,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23718,7 +23756,7 @@ Generated by [AVA](https://avajs.dev).
            23,
          ],
          fixInfo: null,
-          lineNumber: 213,
+          lineNumber: 225,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23734,7 +23772,7 @@ Generated by [AVA](https://avajs.dev).
            22,
          ],
          fixInfo: null,
-          lineNumber: 215,
+          lineNumber: 227,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23750,7 +23788,7 @@ Generated by [AVA](https://avajs.dev).
            42,
          ],
          fixInfo: null,
-          lineNumber: 217,
+          lineNumber: 229,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23766,7 +23804,7 @@ Generated by [AVA](https://avajs.dev).
            21,
          ],
          fixInfo: null,
-          lineNumber: 219,
+          lineNumber: 231,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23782,7 +23820,7 @@ Generated by [AVA](https://avajs.dev).
            21,
          ],
          fixInfo: null,
-          lineNumber: 221,
+          lineNumber: 233,
          ruleDescription: 'Link fragments should be valid',
          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md051.md',
          ruleNames: [
@ -23805,6 +23843,8 @@ Generated by [AVA](https://avajs.dev).
      ␊
      [Valid](#valid-heading-with-emphasis)␊
      ␊
+      [Valid](#valid-heading-with-code)␊
+      ␊
      [Valid](#valid-heading-with-quotes--and-double-quotes-)␊
      ␊
      [Valid](#-valid-heading-with-emoji)␊
@ -23863,6 +23903,10 @@ Generated by [AVA](https://avajs.dev).
      ␊
      Text␊
      ␊
+      ### Valid Heading With \`Code\`␊
+      ␊
+      Text␊
+      ␊
      ### Valid Heading With Quotes ' And Double Quotes "␊
      ␊
      Text␊
@ -23950,9 +23994,12 @@ Generated by [AVA](https://avajs.dev).
      ␊
      [Invalid](#not-an-id-should-be-ignored) {MD051}␊
      ␊
-      [Invalid][badref] {MD051}␊
+      [Invalid {MD051}](#multi-line␊
+      "Title")␊
      ␊
-      [badref]: #missing␊
+      [Invalid][badref]␊
+      ␊
+      [badref]: #missing "{MD051}"␊
      ␊
      ## Inconsistent Case Fragments␊
      ␊
@ -23960,9 +24007,12 @@ Generated by [AVA](https://avajs.dev).
      ␊
      [ALL CAPS](#namedlink) {MD051}␊
      ␊
-      [MiXeD][mixedref] {MD051}␊
+      [Multi-line {MD051}](#NAMEDLINK␊
+      "Title")␊
      ␊
-      [mixedref]: #idLINK␊
+      [MiXeD][mixedref]␊
+      ␊
+      [mixedref]: #idlink "{MD051}"␊
      ␊
      ## Valid Named Fragments␊
      ␊
@ -41804,9 +41854,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%60link',
+          errorContext: '[link](#link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            6,
+            18,
+          ],
          fixInfo: null,
          lineNumber: 81,
          ruleDescription: 'Link fragments should be valid',
@ -41817,9 +41870,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%60link',
+          errorContext: '[link](#link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            11,
+            18,
+          ],
          fixInfo: null,
          lineNumber: 85,
          ruleDescription: 'Link fragments should be valid',
@ -41830,9 +41886,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%60link',
+          errorContext: '[link(link](#link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            6,
+            23,
+          ],
          fixInfo: null,
          lineNumber: 87,
          ruleDescription: 'Link fragments should be valid',
@ -41843,9 +41902,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%60link',
+          errorContext: '[link)link](#link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            6,
+            23,
+          ],
          fixInfo: null,
          lineNumber: 89,
          ruleDescription: 'Link fragments should be valid',
@ -41856,9 +41918,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%5Blink%60link',
+          errorContext: '[link](#link[link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            6,
+            23,
+          ],
          fixInfo: null,
          lineNumber: 91,
          ruleDescription: 'Link fragments should be valid',
@ -41869,9 +41934,12 @@ Generated by [AVA](https://avajs.dev).
          ],
        },
        {
-          errorContext: '#link%5Dlink%60link',
+          errorContext: '[link](#link]link`link)',
          errorDetail: null,
-          errorRange: null,
+          errorRange: [
+            6,
+            23,
+          ],
          fixInfo: null,
          lineNumber: 93,
          ruleDescription: 'Link fragments should be valid',
--- a/test/snapshots/markdownlint-test-scenarios.js.snap
+++ b/test/snapshots/markdownlint-test-scenarios.js.snap