Link checker parses headers inside component

scripts/js/lib/links/extractLinks.test.ts

@@ -29,22 +29,43 @@ test("parseAnchors()", () => {
 
   ## \`code-header\`
 
+  ## Header.with periods-and wild! punctuation?? and numbers 1234 8 (parentheses)
+
+  ## header_using\_underscores
+
+  ## UpperCase Should Be lowercase
+
+  ## repeated
+  ## repeated
+  ## repeated
+
   <Function id="mdx.component.testId" name="testId" signature="testId">
     Convert to dictionary.
 
     **Return type**
 
     \`Dict\`
   </Function>
+
+  <Class>
+      ### Header inside a component
+  </Class>
   `);
   expect(result).toEqual(
     new Set([
       "#my-top-level-heading",
       "#header-2",
       "#code-header",
+      "#headerwith-periods-and-wild-punctuation-and-numbers-1234-8-parentheses",
+      "#header_using_underscores",
+      "#uppercase-should-be-lowercase",
       "#this-is-a-hardcoded-anchor",
       "#another_span",
       "#mdx.component.testId",
+      "#header-inside-a-component",
+      "#repeated",
+      "#repeated-1",
+      "#repeated-2",
     ]),
   );
 });

scripts/js/lib/links/extractLinks.ts

@@ -35,11 +35,28 @@ export type ParsedFile = {
 };
 
 export function parseAnchors(markdown: string): Set<string> {
-  // Anchors generated from markdown titles.
-  const mdAnchors = markdownLinkExtractor(markdown).anchors;
-  // Anchors from HTML id tags.
-  const idAnchors = markdown.match(/(?<=id=")(.+?)(?=")/gm) || [];
-  return new Set([...mdAnchors, ...idAnchors.map((id) => `#${id}`)]);
+  const lines = markdown.split("\n");
+  const anchors = new Set<string>();
+  for (const line of lines) {
+    const heading = line.match(/^\s*#{1,6}\s+(.+?)\s*$/);
+    if (heading) {
+      const normalized = heading[1]
+        .toLowerCase()
+        .trim()
+        .replaceAll(" ", "-")
+        .replaceAll(/[\.,;!?`\\\(\)]/g, "");
+      let deduplicated = normalized;
+      let i = 1;
+      while (anchors.has(`#${deduplicated}`)) {
+        deduplicated = `${normalized}-${i}`;
+        i += 1;
+      }
+      anchors.add(`#${deduplicated}`);
+    }
+    const id = line.match(/(?<=id=")(.+?)(?=")/);
+    if (id) anchors.add(`#${id[1]}`);
+  }
+  return anchors;
 }
 
 export async function parseLinks(