2 files changed, 78 insertions, 1 deletions
diff --git a/cli/tests/unit/net_test.ts b/cli/tests/unit/net_test.ts
index 6769f6301..c7a081bf4 100644
--- a/cli/tests/unit/net_test.ts
+++ b/cli/tests/unit/net_test.ts
@@ -7,6 +7,7 @@ import {
   assertThrows,
   deferred,
   delay,
+  execCode,
 } from "./test_util.ts";
 
 let isCI: boolean;
@@ -807,3 +808,79 @@ Deno.test(
     assertEquals(res, "hello world!");
   },
 );
+
+Deno.test(
+  { permissions: { read: true, run: true } },
+  async function netListenUnref() {
+    const [statusCode, _output] = await execCode(`
+      async function main() {
+        const listener = Deno.listen({ port: 3500 });
+        listener.unref();
+        await listener.accept(); // This doesn't block the program from exiting
+      }
+      main();
+    `);
+    assertEquals(statusCode, 0);
+  },
+);
+
+Deno.test(
+  { permissions: { read: true, run: true } },
+  async function netListenUnref() {
+    const [statusCode, _output] = await execCode(`
+      async function main() {
+        const listener = Deno.listen({ port: 3500 });
+        await listener.accept();
+        listener.unref();
+        await listener.accept(); // The program exits here
+        throw new Error(); // The program doesn't reach here
+      }
+      main();
+      const conn = await Deno.connect({ port: 3500 });
+      conn.close();
+    `);
+    assertEquals(statusCode, 0);
+  },
+);
+
+Deno.test(
+  { permissions: { read: true, run: true, net: true } },
+  async function netListenUnrefAndRef() {
+    const p = execCode(`
+      async function main() {
+        const listener = Deno.listen({ port: 3500 });
+        listener.unref();
+        listener.ref(); // This restores 'ref' state of listener
+        await listener.accept();
+        console.log("accepted")
+      }
+      main();
+    `);
+    // TODO(kt3k): This is racy. Find a correct way to
+    // wait for the server to be ready
+    setTimeout(async () => {
+      const conn = await Deno.connect({ port: 3500 });
+      conn.close();
+    }, 200);
+    const [statusCode, output] = await p;
+    assertEquals(statusCode, 0);
+    assertEquals(output.trim(), "accepted");
+  },
+);
+
+Deno.test(
+  { permissions: { net: true } },
+  async function netListenUnrefConcurrentAccept() {
+    const timer = setTimeout(() => {}, 1000);
+    const listener = Deno.listen({ port: 3500 });
+    listener.accept().catch(() => {});
+    listener.unref();
+    // Unref'd listener still causes Busy error
+    // on concurrent accept calls.
+    await assertRejects(async () => {
+      await listener.accept(); // The program exits here
+    }, Deno.errors.Busy);
+    listener.close();
+    clearTimeout(timer);
+  },
+);
diff --git a/cli/tests/unit/test_util.ts b/cli/tests/unit/test_util.ts
index b18ad9550..36ef8c0e7 100644
--- a/cli/tests/unit/test_util.ts
+++ b/cli/tests/unit/test_util.ts
@@ -30,7 +30,7 @@ export function pathToAbsoluteFileUrl(path: string): URL {
 
 const decoder = new TextDecoder();
 
-export async function execCode(code: string) {
+export async function execCode(code: string): Promise<[number, string]> {
   const p = Deno.run({
     cmd: [
       Deno.execPath(),