3 files changed, 55 insertions, 0 deletions
diff --git a/tests/integration/worker_tests.rs b/tests/integration/worker_tests.rs
index 65c34aa15..aa1c9656e 100644
--- a/tests/integration/worker_tests.rs
+++ b/tests/integration/worker_tests.rs
@@ -137,3 +137,16 @@ itest!(node_worker_transfer_port {
   output: "workers/node_worker_transfer_port.mjs.out",
   exit_code: 0,
 });
+
+itest!(node_worker_message_port_unref {
+  args: "run --quiet --allow-env --allow-read workers/node_worker_message_port_unref.mjs",
+  output: "workers/node_worker_message_port_unref.mjs.out",
+  exit_code: 0,
+});
+
+itest!(node_worker_parent_port_unref {
+  envs: vec![("PARENT_PORT".into(), "1".into())],
+  args: "run --quiet --allow-env --allow-read workers/node_worker_message_port_unref.mjs",
+  output: "workers/node_worker_message_port_unref.mjs.out",
+  exit_code: 0,
+});
diff --git a/tests/testdata/workers/node_worker_message_port_unref.mjs b/tests/testdata/workers/node_worker_message_port_unref.mjs
new file mode 100644
index 000000000..a12be1ec8
--- /dev/null
+++ b/tests/testdata/workers/node_worker_message_port_unref.mjs
@@ -0,0 +1,40 @@
+import {
+  isMainThread,
+  MessageChannel,
+  parentPort,
+  Worker,
+  workerData,
+} from "node:worker_threads";
+
+const useParentPort = Deno.env.get("PARENT_PORT") === "1";
+
+if (useParentPort) {
+  if (isMainThread) {
+    const worker = new Worker(import.meta.filename);
+    worker.postMessage("main says hi!");
+    worker.on("message", (msg) => console.log(msg));
+  } else {
+    parentPort.on("message", (msg) => {
+      console.log(msg);
+      parentPort.postMessage("worker says hi!");
+      parentPort.unref();
+    });
+  }
+} else {
+  if (isMainThread) {
+    const { port1, port2 } = new MessageChannel();
+    const worker = new Worker(import.meta.filename, {
+      workerData: port2,
+      transferList: [port2],
+    });
+    port1.postMessage("main says hi!");
+    port1.on("message", (msg) => console.log(msg));
+  } else {
+    const port = workerData;
+    port.on("message", (msg) => {
+      console.log(msg);
+      port.postMessage("worker says hi!");
+      port.unref();
+    });
+  }
+}
diff --git a/tests/testdata/workers/node_worker_message_port_unref.mjs.out b/tests/testdata/workers/node_worker_message_port_unref.mjs.out
new file mode 100644
index 000000000..c9d5325bc
--- /dev/null
+++ b/tests/testdata/workers/node_worker_message_port_unref.mjs.out
@@ -0,0 +1,2 @@
+main says hi!
+worker says hi!