1

tests/browser-worker-node-shim.mjs

@@ -0,0 +1,41 @@
+import { parentPort, Worker as NodeWorker } from "node:worker_threads";
+
+if (!parentPort) throw new Error("browser-worker-node-shim requires a worker_threads parent port.");
+
+class BrowserStyleNestedWorker {
+  constructor(url) {
+    const moduleUrl = url instanceof URL ? url.href : new URL(String(url), import.meta.url).href;
+    this.onmessage = null;
+    this.onerror = null;
+    this._worker = new NodeWorker(new URL("./browser-nested-worker-node-shim.mjs", import.meta.url), {
+      type: "module",
+      workerData: { moduleUrl },
+    });
+    this._worker.on("message", (data) => this.onmessage?.({ data }));
+    this._worker.on("error", (error) => this.onerror?.({ message: error?.message || String(error), error }));
+  }
+
+  postMessage(message, transfer = []) {
+    this._worker.postMessage(message, transfer);
+  }
+
+  terminate() {
+    return this._worker.terminate();
+  }
+}
+
+globalThis.Worker = BrowserStyleNestedWorker;
+globalThis.self = {
+  onmessage: null,
+  postMessage(message, transfer = []) {
+    parentPort.postMessage(message, transfer);
+  },
+};
+
+await import("../src/mapPatchWorker.js");
+
+if (typeof globalThis.self.onmessage !== "function") {
+  throw new Error("mapPatchWorker did not install its browser Worker message handler.");
+}
+
+parentPort.on("message", (data) => globalThis.self.onmessage({ data }));