Refactor Token.parent() to Token.parent, add validation tests for parent, fix parent in htmlFlow scenario, improve type saftey slightly.

.eslintrc.json

@@ -87,6 +87,7 @@
     "id-length": "off",
     "indent": ["error", 2, { "SwitchCase": 1 }],
     "linebreak-style": "off",
+    "lines-around-comment": "off",
     "logical-assignment-operators": "off",
     "max-depth": "off",
     "max-lines": "off",

demo/markdownlint-browser.js

@@ -1219,14 +1219,7 @@ var flatTokensSymbol = Symbol("flat-tokens");
  * @property {number} endColumn End column (1-based).
  * @property {string} text Token text.
  * @property {Token[]} children Child tokens.
- * @property {GetTokenParent} parent Parent token.
+ * @property {Token | null} parent Parent token.
- */
-
-/**
- * Returns parent Token of a Token.
- *
- * @typedef {Function} GetTokenParent
- * @returns {Token} Parent token.
  */
 
 /**
@@ -1290,17 +1283,26 @@ function getMicromarkEvents(markdown) {
  * @param {Object} micromarkOptions Options for micromark.
  * @param {boolean} referencesDefined Treat references as defined.
  * @param {number} lineDelta Offset to apply to start/end line.
+ * @param {Token} [ancestor] Parent of top-most tokens.
  * @returns {Token[]} Micromark tokens (frozen).
  */
-function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined, lineDelta) {
+function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined, lineDelta, ancestor) {
   // Use micromark to parse document into Events
   var events = getMicromarkEvents(markdown, micromarkOptions, referencesDefined);
 
   // Create Token objects
   var document = [];
   var flatTokens = [];
+  /** @type {Token} */
   var root = {
-    "children": document
+    "type": "ROOT",
+    "startLine": -1,
+    "startColumn": -1,
+    "endLine": -1,
+    "endColumn": -1,
+    "text": "ROOT",
+    "children": document,
+    "parent": null
   };
   var history = [root];
   var current = root;
@@ -1310,7 +1312,7 @@ function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined,
   var _iterator = _createForOfIteratorHelper(events),
     _step;
   try {
-    var _loop = function _loop() {
+    for (_iterator.s(); !(_step = _iterator.n()).done;) {
       var event = _step.value;
       var _event = _slicedToArray(event, 3),
         kind = _event[0],
@@ -1335,13 +1337,10 @@ function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined,
           endColumn: endColumn,
           text: text,
           "children": [],
-          "parent": function parent() {
+          "parent": previous === root ? ancestor || null : previous
-            return previous === root ? null : previous;
-          }
         };
         previous.children.push(current);
         flatTokens.push(current);
-        // @ts-ignore
         if (current.type === "htmlFlow" && !isHtmlFlowComment(current)) {
           skipHtmlFlowChildren = true;
           if (!reparseOptions || !lines) {
@@ -1355,7 +1354,7 @@ function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined,
             lines = markdown.split(newLineRe);
           }
           var reparseMarkdown = lines.slice(current.startLine - 1, current.endLine).join("\n");
-          var tokens = micromarkParseWithOffset(reparseMarkdown, reparseOptions, referencesDefined, current.startLine - 1);
+          var tokens = micromarkParseWithOffset(reparseMarkdown, reparseOptions, referencesDefined, current.startLine - 1, current);
           current.children = tokens;
           // Avoid stack overflow of Array.push(...spread)
           // eslint-disable-next-line unicorn/prefer-spread
@@ -1372,9 +1371,6 @@ function micromarkParseWithOffset(markdown, micromarkOptions, referencesDefined,
           current = history.pop();
         }
       }
-    };
-    for (_iterator.s(); !(_step = _iterator.n()).done;) {
-      _loop();
     }
 
     // Return document
@@ -3575,6 +3571,11 @@ var _require = __webpack_require__(/*! ../helpers */ "../helpers/helpers.js"),
   addErrorDetailIf = _require.addErrorDetailIf;
 var _require2 = __webpack_require__(/*! ../helpers/micromark.cjs */ "../helpers/micromark.cjs"),
   filterByTypes = _require2.filterByTypes;
+
+/**
+ * @typedef {import("../helpers/micromark.cjs").Token} Token
+ */
+
 module.exports = {
   "names": ["MD007", "ul-indent"],
   "description": "Unordered list indentation",
@@ -3591,15 +3592,17 @@ module.exports = {
     try {
       for (_iterator.s(); !(_step = _iterator.n()).done;) {
         var token = _step.value;
-        var startColumn = token.startColumn,
+        var parent = token.parent,
+          startColumn = token.startColumn,
           startLine = token.startLine,
           type = token.type;
         if (type === "blockQuotePrefix") {
           lastBlockQuotePrefix = token;
         } else if (type === "listUnordered") {
           var nesting = 0;
+          /** @type {Token | null} */
           var current = token;
-          while (current = current.parent()) {
+          while (current = current.parent) {
             if (current.type === "listUnordered") {
               nesting++;
             } else if (current.type === "listOrdered") {
@@ -3614,7 +3617,7 @@ module.exports = {
           }
         } else {
           // listItemPrefix
-          var _nesting = unorderedListNesting.get(token.parent());
+          var _nesting = unorderedListNesting.get(parent);
           if (_nesting !== undefined) {
             var _lastBlockQuotePrefix;
             // listItemPrefix for listUnordered

helpers/micromark.cjs

@@ -23,14 +23,7 @@ const flatTokensSymbol = Symbol("flat-tokens");
  * @property {number} endColumn End column (1-based).
  * @property {string} text Token text.
  * @property {Token[]} children Child tokens.
- * @property {GetTokenParent} parent Parent token.
+ * @property {Token | null} parent Parent token.
- */
-
-/**
- * Returns parent Token of a Token.
- *
- * @typedef {Function} GetTokenParent
- * @returns {Token} Parent token.
  */
 
 /**
@@ -105,13 +98,15 @@ function getMicromarkEvents(
  * @param {Object} micromarkOptions Options for micromark.
  * @param {boolean} referencesDefined Treat references as defined.
  * @param {number} lineDelta Offset to apply to start/end line.
+ * @param {Token} [ancestor] Parent of top-most tokens.
  * @returns {Token[]} Micromark tokens (frozen).
  */
 function micromarkParseWithOffset(
   markdown,
   micromarkOptions,
   referencesDefined,
-  lineDelta
+  lineDelta,
+  ancestor
 ) {
   // Use micromark to parse document into Events
   const events = getMicromarkEvents(
@@ -121,8 +116,16 @@ function micromarkParseWithOffset(
   // Create Token objects
   const document = [];
   let flatTokens = [];
+  /** @type {Token} */
   const root = {
-    "children": document
+    "type": "ROOT",
+    "startLine": -1,
+    "startColumn": -1,
+    "endLine": -1,
+    "endColumn": -1,
+    "text": "ROOT",
+    "children": document,
+    "parent": null
   };
   const history = [ root ];
   let current = root;
@@ -146,11 +149,10 @@ function micromarkParseWithOffset(
         endColumn,
         text,
         "children": [],
-        "parent": () => (previous === root ? null : previous)
+        "parent": ((previous === root) ? (ancestor || null) : previous)
       };
       previous.children.push(current);
       flatTokens.push(current);
-      // @ts-ignore
       if ((current.type === "htmlFlow") && !isHtmlFlowComment(current)) {
         skipHtmlFlowChildren = true;
         if (!reparseOptions || !lines) {
@@ -173,7 +175,8 @@ function micromarkParseWithOffset(
           reparseMarkdown,
           reparseOptions,
           referencesDefined,
-          current.startLine - 1
+          current.startLine - 1,
+          current
         );
         current.children = tokens;
         // Avoid stack overflow of Array.push(...spread)

lib/md007.js

@@ -5,6 +5,10 @@
 const { addErrorDetailIf } = require("../helpers");
 const { filterByTypes } = require("../helpers/micromark.cjs");
 
+/**
+ * @typedef {import("../helpers/micromark.cjs").Token} Token
+ */
+
 module.exports = {
   "names": [ "MD007", "ul-indent" ],
   "description": "Unordered list indentation",
@@ -20,13 +24,14 @@ module.exports = {
       [ "blockQuotePrefix", "listItemPrefix", "listUnordered" ]
     );
     for (const token of tokens) {
-      const { startColumn, startLine, type } = token;
+      const { parent, startColumn, startLine, type } = token;
       if (type === "blockQuotePrefix") {
         lastBlockQuotePrefix = token;
       } else if (type === "listUnordered") {
         let nesting = 0;
+        /** @type {Token | null} */
         let current = token;
-        while ((current = current.parent())) {
+        while ((current = current.parent)) {
           if (current.type === "listUnordered") {
             nesting++;
           } else if (current.type === "listOrdered") {
@@ -41,7 +46,7 @@ module.exports = {
         }
       } else {
         // listItemPrefix
-        const nesting = unorderedListNesting.get(token.parent());
+        const nesting = unorderedListNesting.get(parent);
         if (nesting !== undefined) {
           // listItemPrefix for listUnordered
           const expectedIndent =

test/markdownlint-test-custom-rules.js

@@ -1489,7 +1489,11 @@ test("customRulesParamsAreFrozen", (t) => {
               t.true(Object.isFrozen(current) || (current === params));
               for (const name of Object.getOwnPropertyNames(current)) {
                 const value = current[name];
-                if (value && (typeof value === "object")) {
+                if (
+                  value &&
+                  (typeof value === "object") &&
+                  (name !== "parent")
+                ) {
                   pending.push(value);
                 }
               }

test/markdownlint-test-micromark.mjs

@@ -17,9 +17,26 @@ const testTokens = new Promise((resolve, reject) => {
   testContent.then(parse).then(resolve, reject);
 });
 
+const cloneToken = (token) => {
+  for (const child of token.children) {
+    const expectedParent = (token.type ? token : null);
+    if (child.parent !== expectedParent) {
+      throw new Error("Unexpected parent.");
+    }
+  }
+  const clone = { ...token };
+  delete clone.parent;
+  clone.children = clone.children.map(cloneToken);
+  return clone;
+};
+
+const cloneTokens = (tokens) => (
+  cloneToken({ "children": tokens }).children
+);
+
 test("parse", async(t) => {
   t.plan(1);
-  t.snapshot(await testTokens, "Unexpected tokens");
+  t.snapshot(cloneTokens(await testTokens), "Unexpected tokens");
 });
 
 test("getMicromarkEvents/filterByPredicate", async(t) => {