fix(redis-worker): guard resilient require shim

Author: carderne

packages/redis-worker/package.json

@@ -37,6 +37,7 @@
     "@internal/tracing": "workspace:*",
     "@types/lodash.omit": "^4.5.7",
     "@types/seedrandom": "^3.0.8",
+    "esbuild": "^0.23.0",
     "rimraf": "6.0.1",
     "tsdown": "0.22.10",
     "tsx": "4.17.0"

packages/redis-worker/test/build-output.test.ts

@@ -0,0 +1,44 @@
+import { build } from "esbuild";
+import { mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { createRequire } from "node:module";
+import { fileURLToPath } from "node:url";
+import { spawnSync } from "node:child_process";
+import { afterAll, expect, test } from "vitest";
+
+const packageDir = fileURLToPath(new URL("../", import.meta.url));
+const tempDir = mkdtempSync(join(tmpdir(), "redis-worker-build-output-"));
+
+const require = createRequire(import.meta.url);
+
+afterAll(() => {
+  rmSync(tempDir, { recursive: true, force: true });
+});
+
+test("the ESM output can be rebundled and loaded as CommonJS", async () => {
+  const buildResult = spawnSync("pnpm", ["exec", "tsdown"], {
+    cwd: packageDir,
+    encoding: "utf8",
+  });
+  const buildOutput = [buildResult.stdout, buildResult.stderr].filter(Boolean).join("\n");
+
+  expect(buildResult.error, buildOutput).toBeUndefined();
+  expect(buildResult.status, buildOutput).toBe(0);
+
+  const esmPath = join(packageDir, "dist/index.js");
+  const esmOutput = readFileSync(esmPath, "utf8");
+  expect(esmOutput).not.toMatch(/\b[\w$]*createRequire[\w$]*\s*\(\s*import\.meta\.url\s*\)/);
+
+  const cjsPath = join(tempDir, "index.cjs");
+  await build({
+    entryPoints: [esmPath],
+    outfile: cjsPath,
+    bundle: true,
+    format: "cjs",
+    platform: "node",
+    logLevel: "silent",
+  });
+
+  expect(() => require(cjsPath)).not.toThrow();
+}, 30_000);

packages/redis-worker/tsdown.config.ts

@@ -60,15 +60,28 @@ export default defineConfig({
     {
       name: "resilient-create-require",
       renderChunk(code: string) {
-        if (!code.includes("createRequire(import.meta.url)")) return null;
+        const unsafeCreateRequire = /(\b[\w$]*createRequire[\w$]*\s*\()\s*import\.meta\.url\s*\)/g;
+        const patched = code.replace(
+          unsafeCreateRequire,
+          "$1import.meta.url || process.cwd() + '/index.js')"
+        );
+
+        if (patched === code) return null;
+
         return {
-          code: code.replaceAll(
-            "createRequire(import.meta.url)",
-            "createRequire(import.meta.url || process.cwd() + '/index.js')"
-          ),
+          code: patched,
           map: null,
         };
       },
+      generateBundle(_options, bundle) {
+        const unsafeCreateRequire = /\b[\w$]*createRequire[\w$]*\s*\(\s*import\.meta\.url\s*\)/;
+
+        for (const output of Object.values(bundle)) {
+          if (output.type === "chunk" && unsafeCreateRequire.test(output.code)) {
+            throw new Error(`Unsafe createRequire helper remained in ${output.fileName}`);
+          }
+        }
+      },
     },
   ],
 });