Markdownlint TOP007 bug: Account for non-codepen closing </p> tags (#…

…27876)

* Fix bug with non-codepen closing </p> tags

Bug affected files with </p> tags somewhere before (or without) any
codepen embeds, due to trying to push to undefined.

* Add example of </p> exception fixed by this change to test file

markdownlint/TOP007_useMarkdownLinks/TOP007_useMarkdownLinks.js

@@ -23,12 +23,14 @@ module.exports = {
       .map((token) => token.map);
 
     const codepenLineRanges = params.lines.reduce((lineRanges, currentLine, index) => {
-      const range = [];
       const lineNumber = index + 1;
-      if (currentLine.includes('class="codepen"')) {
-        range.push(lineNumber);
-        lineRanges.push(range);
-      } else if (currentLine.trim().startsWith("</p>")) {
+      const isCodepenOpeningTag = currentLine.includes('class="codepen"');
+      const isCodepenClosingTag =
+        currentLine.trim().startsWith("</p>") && lineRanges.at(-1)?.length < 2;
+
+      if (isCodepenOpeningTag) {
+        lineRanges.push([lineNumber]);
+      } else if (isCodepenClosingTag) {
         lineRanges.at(-1).push(lineNumber);
       }
 

markdownlint/TOP007_useMarkdownLinks/tests/TOP007_test.md

@@ -18,6 +18,12 @@ Assignment section
 
 #### Custom section
 
+```html
+<p>
+    The following  &lt;/p&gt; should be ignored by this rule as it does not belong to a codepen embed.
+</p>
+```
+
 [Markdown links are desired in most cases](#custom-section)
 
 <a href="#custom-section">Link should flag as we should be using a markdown link instead</a>.