fix(lint): avoid unproven media and head leaks

packages/lint/src/project.test.ts

@@ -235,3 +235,36 @@ describe("template shell style sources", () => {
     expect(findings.some((finding) => finding.code === "texture_mask_asset_not_found")).toBe(true);
   });
 });
+
+describe("duplicate_audio_track", () => {
+  async function duplicateAudioFindings(audioMarkup: string): Promise<HyperframeLintFinding[]> {
+    const project = makeProject(`<html><body>
+      <div data-composition-id="main" data-width="1920" data-height="1080" data-start="0" data-duration="20">
+        ${audioMarkup}
+      </div>
+      <script>window.__timelines = {};</script>
+    </body></html>`);
+    const { results } = await lintProject(project);
+    return results
+      .flatMap((entry) => entry.result.findings)
+      .filter((finding) => finding.code === "duplicate_audio_track");
+  }
+
+  it("does not infer overlap when same-track clips omit data-duration", async () => {
+    const findings = await duplicateAudioFindings(`
+      <audio id="first" src="voice.wav" data-track-index="0" data-start="0"></audio>
+      <audio id="second" src="voice.wav" data-track-index="0" data-start="10"></audio>
+    `);
+
+    expect(findings).toHaveLength(0);
+  });
+
+  it("still reports overlap when explicit clip durations overlap", async () => {
+    const findings = await duplicateAudioFindings(`
+      <audio id="first" src="voice.wav" data-track-index="0" data-start="0" data-duration="12"></audio>
+      <audio id="second" src="voice.wav" data-track-index="0" data-start="10" data-duration="5"></audio>
+    `);
+
+    expect(findings).toHaveLength(1);
+  });
+});

packages/lint/src/project.ts

@@ -503,11 +503,11 @@ function lintDuplicateAudioTracks(htmlSources: HtmlSource[]): HyperframeLintFind
       const startStr = extractAttr(tag, "data-start");
       const durStr = extractAttr(tag, "data-duration");
       const src = extractAttr(tag, "src") ?? "unknown";
-      if (!trackStr || !startStr) continue;
+      if (!trackStr || !startStr || !durStr) continue;
 
       const trackIndex = parseInt(trackStr, 10);
       const start = parseFloat(startStr);
-      const duration = durStr ? parseFloat(durStr) : Infinity;
+      const duration = parseFloat(durStr);
       const key = `${src}:${start}:${duration}:${trackIndex}`;
       if (seen.has(key)) continue;
       seen.add(key);

packages/lint/src/rules/core.test.ts

@@ -464,6 +464,17 @@ body {
     expect(finding).toBeUndefined();
   });
 
+  it("does not treat a head tag literal inside a template script comment as document head", async () => {
+    const html = compositionWithBodyPrefix(
+      "",
+      `<template><script>// Explain the literal <head> marker.</script></template>`,
+    );
+    const result = await lintHyperframeHtml(html);
+    const finding = result.findings.find((f) => f.code === "head_leaked_text");
+
+    expect(finding).toBeUndefined();
+  });
+
   it("does not report CSS-looking educational text inside the composition root", async () => {
     const html = compositionWithBodyPrefix(
       "",

packages/lint/src/rules/core.ts

@@ -107,12 +107,14 @@ function findLeakedTextInHeadContent(headContent: string): string | null {
 }
 
 function findLeakedTextInHead(rawSource: string): string | null {
-  const headMatches = [...rawSource.matchAll(HEAD_CONTENT_PATTERN)];
-  for (const match of headMatches) {
-    const leakedText = findLeakedTextInHeadContent(match[1] ?? "");
-    if (leakedText) return leakedText;
-  }
-  return null;
+  const headPattern = new RegExp(HEAD_CONTENT_PATTERN.source, "i");
+  const match = headPattern.exec(rawSource);
+  if (!match) return null;
+
+  const bodyIndex = rawSource.search(/<body\b/i);
+  if (bodyIndex >= 0 && match.index > bodyIndex) return null;
+
+  return findLeakedTextInHeadContent(match[1] ?? "");
 }
 
 function findLeakedTextBetweenHeadAndBody(rawSource: string): string | null {