fix(bundler): inline runtime body, drop bare-semi joins, drop empty catch binding

packages/cli/src/commands/layout.ts

@@ -1,6 +1,6 @@
 import { defineCommand } from "citty";
 import { existsSync, readFileSync } from "node:fs";
-import { dirname, join, resolve } from "node:path";
+import { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
 import type { Example } from "./_examples.js";
 import { c } from "../ui/colors.js";
@@ -107,27 +107,10 @@ async function seekTo(page: import("puppeteer-core").Page, time: number): Promis
 }
 
 async function bundleProjectHtml(projectDir: string): Promise<string> {
+  // `bundleToSingleHtml` now inlines the runtime IIFE by default, so the
+  // previous post-bundle runtime substitution is no longer needed.
   const { bundleToSingleHtml } = await import("@hyperframes/core/compiler");
-  let html = await bundleToSingleHtml(projectDir);
-
-  const runtimePath = resolve(
-    __dirname,
-    "..",
-    "..",
-    "..",
-    "core",
-    "dist",
-    "hyperframe.runtime.iife.js",
-  );
-  if (existsSync(runtimePath)) {
-    const runtimeSource = readFileSync(runtimePath, "utf-8");
-    html = html.replace(
-      /<script[^>]*data-hyperframes-preview-runtime[^>]*src="[^"]*"[^>]*><\/script>/,
-      () => `<script data-hyperframes-preview-runtime="1">${runtimeSource}</script>`,
-    );
-  }
-
-  return html;
+  return bundleToSingleHtml(projectDir);
 }
 
 async function alignViewportToComposition(

packages/cli/src/commands/snapshot.ts

@@ -97,20 +97,9 @@ async function captureSnapshots(
 
   const numFrames = opts.frames ?? 5;
 
-  // 1. Bundle
-  let html = await bundleToSingleHtml(projectDir);
-
-  // Inject local runtime if available.
-  // Uses the same multi-strategy resolver as the studio preview server
-  // (runtimeSource.ts) so snapshot works in dev (tsx), built CLI, and npx.
-  const { loadRuntimeSource } = await import("../server/runtimeSource.js");
-  const runtimeSource = await loadRuntimeSource();
-  if (runtimeSource) {
-    html = html.replace(
-      /<script[^>]*data-hyperframes-preview-runtime[^>]*src="[^"]*"[^>]*><\/script>/,
-      () => `<script data-hyperframes-preview-runtime="1">${runtimeSource}</script>`,
-    );
-  }
+  // 1. Bundle. `bundleToSingleHtml` now inlines the runtime IIFE by default,
+  // so the previous post-bundle runtime substitution is no longer needed.
+  const html = await bundleToSingleHtml(projectDir);
 
   const server = await serveStaticProjectHtml(projectDir, html);
 

packages/cli/src/commands/validate.ts

@@ -1,6 +1,6 @@
 import { defineCommand } from "citty";
 import { existsSync, readFileSync } from "node:fs";
-import { resolve, join, dirname } from "node:path";
+import { join, dirname } from "node:path";
 import { fileURLToPath } from "node:url";
 import { resolveProject } from "../utils/project.js";
 import { resolveCompositionViewportFromHtml } from "../utils/compositionViewport.js";
@@ -113,24 +113,10 @@ async function validateInBrowser(
   const { bundleToSingleHtml } = await import("@hyperframes/core/compiler");
   const { ensureBrowser } = await import("../browser/manager.js");
 
-  let html = await bundleToSingleHtml(projectDir);
-
-  const runtimePath = resolve(
-    __dirname,
-    "..",
-    "..",
-    "..",
-    "core",
-    "dist",
-    "hyperframe.runtime.iife.js",
-  );
-  if (existsSync(runtimePath)) {
-    const runtimeSource = readFileSync(runtimePath, "utf-8");
-    html = html.replace(
-      /<script[^>]*data-hyperframes-preview-runtime[^>]*src="[^"]*"[^>]*><\/script>/,
-      () => `<script data-hyperframes-preview-runtime="1">${runtimeSource}</script>`,
-    );
-  }
+  // `bundleToSingleHtml` now inlines the runtime IIFE by default, so the
+  // previous post-bundle regex substitution (which matched `src="..."` on the
+  // runtime tag) is no longer needed — there's no `src` attribute to match.
+  const html = await bundleToSingleHtml(projectDir);
 
   const { createServer } = await import("node:http");
   const { getMimeType } = await import("@hyperframes/core/studio-api");

packages/cli/src/server/studioServer.ts

@@ -153,8 +153,11 @@ export function createStudioServer(options: StudioServerOptions): StudioServer {
     async bundle(dir: string): Promise<string | null> {
       try {
         const { bundleToSingleHtml } = await import("@hyperframes/core/compiler");
-        let html = await bundleToSingleHtml(dir);
-        // Fix empty runtime src from bundler — point to the local runtime endpoint
+        // Studio dev server: ask the bundler for an empty `src=""` placeholder so
+        // we can point it at our hot-reloadable local runtime endpoint. Inlining
+        // ~150 KB of runtime body on every preview render would defeat browser
+        // caching across composition edits.
+        let html = await bundleToSingleHtml(dir, { runtime: "placeholder" });
         html = html.replace(
           'data-hyperframes-preview-runtime="1" src=""',
           'data-hyperframes-preview-runtime="1" src="/api/runtime.js"',

packages/core/src/compiler/compositionScoping.ts

@@ -212,7 +212,11 @@ export function wrapScopedCompositionScript(
         value: __hfFindRoot(),
         configurable: true,
       });
-    } catch (_err) {}
+    } catch {
+      // Best-effort: timelines coming from user code may have a frozen target
+      // or a non-extensible defineProperty path. Swallow — the scoped root
+      // is an enrichment, not a correctness invariant for playback.
+    }
     return timeline;
   };
   var __hfBaseGsap = typeof gsap === "undefined" ? window.gsap : gsap;
@@ -282,5 +286,5 @@ ${source}
   };
   __hfFindRoot();
   __hfRun();
-})()`;
+})();`;
 }

packages/core/src/compiler/htmlBundler.test.ts

@@ -38,10 +38,116 @@ describe("bundleToSingleHtml", () => {
     )?.[0];
 
     expect(runtimeBlock).toBeDefined();
-    expect(runtimeBlock).not.toContain("getElementById");
+    // The runtime block must contain the inlined HF runtime IIFE — bundled
+    // output is self-contained, so the bundle's runtime body is loaded inline,
+    // not referenced via src.
+    expect(runtimeBlock).toMatch(/data-hyperframes-preview-runtime="1">/);
+    expect(runtimeBlock).not.toMatch(/src=""/);
+    // The author's specific composition script must NOT be merged INTO the
+    // runtime tag — it stays as its own <script> elsewhere in the document.
+    expect(runtimeBlock).not.toContain("window.__timelines.main = { duration:");
     expect(bundled).toContain('document.getElementById("scene")');
   });
 
+  it("produces a self-contained runtime script when no HYPERFRAME_RUNTIME_URL is set", async () => {
+    // Regression guard: hf#XXX. The bundler used to emit
+    // <script ... src=""></script> when no runtime URL was configured. An
+    // empty src resolves to the page URL itself, which Chrome flags as an
+    // infinite-fetch hazard. Verify that bundleToSingleHtml inlines the
+    // runtime body so the bundle is genuinely self-contained.
+    const dir = makeTempProject({
+      "index.html": `<!doctype html>
+<html><body>
+  <div data-composition-id="root" data-width="320" data-height="180"></div>
+</body></html>`,
+    });
+
+    const previousUrl = process.env.HYPERFRAME_RUNTIME_URL;
+    delete process.env.HYPERFRAME_RUNTIME_URL;
+    let bundled: string;
+    try {
+      bundled = await bundleToSingleHtml(dir);
+    } finally {
+      if (previousUrl !== undefined) process.env.HYPERFRAME_RUNTIME_URL = previousUrl;
+    }
+
+    const runtimeBlock = bundled.match(
+      /<script\b[^>]*data-hyperframes-preview-runtime[^>]*>[\s\S]*?<\/script>/i,
+    )?.[0];
+    expect(runtimeBlock).toBeDefined();
+    // Must NOT have an empty src attribute (would self-fetch).
+    expect(runtimeBlock).not.toMatch(/src=""/);
+    // Must have a non-trivial inlined body (the runtime IIFE is ~150KB).
+    const innerLength = (runtimeBlock!.match(/>([\s\S]*?)<\/script>/)?.[1] ?? "").length;
+    expect(innerLength).toBeGreaterThan(1000);
+  });
+
+  it("preserves chunk integrity when a chunk ends with a line comment (ASI hazard guard)", async () => {
+    // Regression guard for the joinJsChunks helper. If a chunk ends with `// ...`
+    // and we naively appended `;` on the same line, the appended semicolon would
+    // be eaten by the comment, leaving the next chunk's first statement attached
+    // to the previous chunk's last expression. Verify the helper appends `\n;`
+    // instead so the comment terminates and the semicolon stands alone.
+    const dir = makeTempProject({
+      "index.html": `<!doctype html>
+<html><body>
+  <div data-composition-id="root" data-width="320" data-height="180"></div>
+  <script src="local-a.js"></script>
+  <script src="local-b.js"></script>
+  <script>window.__timelines = window.__timelines || {}; window.__timelines.root = {}</script>
+</body></html>`,
+      // Chunk A ends with a // line comment — without the \n separator before
+      // the appended ;, that ; would be eaten by the comment.
+      "local-a.js": "window.__a = 1 // trailing line comment",
+      "local-b.js": "window.__b = 2",
+    });
+
+    const bundled = await bundleToSingleHtml(dir);
+    // Run every inline script body through esbuild; if the line comment ate
+    // the separator, parse would fail with an unexpected-token error somewhere
+    // around the chunk boundary. Use a real HTML parser (CodeQL flags regex-
+    // based script extraction as bad-tag-filter).
+    const { transformSync } = await import("esbuild");
+    const { document } = parseHTML(bundled);
+    for (const script of document.querySelectorAll("script")) {
+      const body = script.textContent;
+      if (!body || !body.trim()) continue;
+      expect(() => transformSync(body, { loader: "js", minify: false })).not.toThrow();
+    }
+  });
+
+  it("does not produce stray bare-semicolon lines between concatenated JS chunks", async () => {
+    // Regression guard: hf#XXX. Earlier the bundler joined script chunks with
+    // `\n;\n`, which produces a lone `;` on its own line between chunks. Valid
+    // JS but reads as a code smell. Each chunk should end in `;` and chunks
+    // should join with `\n`.
+    const dir = makeTempProject({
+      "index.html": `<!doctype html>
+<html><body>
+  <div data-composition-id="root" data-width="320" data-height="180">
+    <div id="child-host"
+         data-composition-id="child"
+         data-composition-src="compositions/child.html"
+         data-start="0" data-duration="2"></div>
+  </div>
+  <script src="local-a.js"></script>
+  <script src="local-b.js"></script>
+  <script>window.__timelines = window.__timelines || {}; window.__timelines.root = {}</script>
+</body></html>`,
+      "local-a.js": "window.__a = 1",
+      "local-b.js": "window.__b = 2",
+      "compositions/child.html": `<template id="child-template">
+  <div data-composition-id="child" data-width="320" data-height="180">
+    <script>window.__c = 3</script>
+  </div>
+</template>`,
+    });
+
+    const bundled = await bundleToSingleHtml(dir);
+    // No line is JUST a bare semicolon (with optional surrounding whitespace).
+    expect(bundled).not.toMatch(/\n\s*;\s*\n/);
+  });
+
   it("hoists external CDN scripts from sub-compositions into the bundle", async () => {
     const dir = makeTempProject({
       "index.html": `<!doctype html>
@@ -84,8 +190,14 @@ describe("bundleToSingleHtml", () => {
     // GSAP CDN from main doc should still be present
     expect(bundled).toContain("cdn.jsdelivr.net/npm/gsap");
 
-    // data-composition-src should be stripped (composition was inlined)
-    expect(bundled).not.toContain("data-composition-src");
+    // data-composition-src should be stripped from the host element (composition
+    // was inlined). The literal string may still appear inside the inlined
+    // runtime IIFE that knows how to look up that attribute — so check the DOM,
+    // not the raw text.
+    const { document: doc } = parseHTML(bundled);
+    const hostEl = doc.getElementById("rockets-host");
+    expect(hostEl).toBeTruthy();
+    expect(hostEl?.hasAttribute("data-composition-src")).toBe(false);
   });
 
   it("does not duplicate CDN scripts already present in the main document", async () => {