3 files changed, 25 insertions, 3 deletions
diff --git a/cli/dts/lib.deno.shared_globals.d.ts b/cli/dts/lib.deno.shared_globals.d.ts
index 849f9f835..26e3d1d5b 100644
--- a/cli/dts/lib.deno.shared_globals.d.ts
+++ b/cli/dts/lib.deno.shared_globals.d.ts
@@ -411,7 +411,7 @@ declare class Worker extends EventTarget {
     options?: WorkerOptions,
   );
   postMessage(message: any, transfer: Transferable[]): void;
-  postMessage(message: any, options?: PostMessageOptions): void;
+  postMessage(message: any, options?: StructuredSerializeOptions): void;
   addEventListener<K extends keyof WorkerEventMap>(
     type: K,
     listener: (this: Worker, ev: WorkerEventMap[K]) => any,
diff --git a/cli/dts/lib.deno.worker.d.ts b/cli/dts/lib.deno.worker.d.ts
index d35828135..34865b251 100644
--- a/cli/dts/lib.deno.worker.d.ts
+++ b/cli/dts/lib.deno.worker.d.ts
@@ -70,7 +70,7 @@ declare class DedicatedWorkerGlobalScope extends WorkerGlobalScope {
     | null;
   close(): void;
   postMessage(message: any, transfer: Transferable[]): void;
-  postMessage(message: any, options?: PostMessageOptions): void;
+  postMessage(message: any, options?: StructuredSerializeOptions): void;
   addEventListener<K extends keyof DedicatedWorkerGlobalScopeEventMap>(
     type: K,
     listener: (
@@ -108,7 +108,10 @@ declare var onmessageerror:
   | null;
 declare function close(): void;
 declare function postMessage(message: any, transfer: Transferable[]): void;
-declare function postMessage(message: any, options?: PostMessageOptions): void;
+declare function postMessage(
+  message: any,
+  options?: StructuredSerializeOptions,
+): void;
 declare var navigator: WorkerNavigator;
 declare var onerror:
   | ((this: DedicatedWorkerGlobalScope, ev: ErrorEvent) => any)
diff --git a/cli/tests/unit/structured_clone_test.ts b/cli/tests/unit/structured_clone_test.ts
new file mode 100644
index 000000000..f25276165
--- /dev/null
+++ b/cli/tests/unit/structured_clone_test.ts
@@ -0,0 +1,19 @@
+import { assert, assertEquals } from "./test_util.ts";
+
+// Basic tests for the structured clone algorithm. Mainly tests TypeScript
+// typings. Actual functionality is tested in WPT.
+
+Deno.test("self.structuredClone", async () => {
+  const arrayOriginal = ["hello world"];
+  const channelOriginal = new MessageChannel();
+  const [arrayCloned, portTransferred] = self
+    .structuredClone([arrayOriginal, channelOriginal.port2], {
+      transfer: [channelOriginal.port2],
+    });
+  assert(arrayOriginal !== arrayCloned); // not the same identity
+  assertEquals(arrayCloned, arrayOriginal); // but same value
+  channelOriginal.port1.postMessage("1");
+  await new Promise((resolve) => portTransferred.onmessage = () => resolve(1));
+  channelOriginal.port1.close();
+  portTransferred.close();
+});