1 files changed, 27 insertions, 2 deletions
diff --git a/cli/tests/unit/spawn_test.ts b/cli/tests/unit/spawn_test.ts
index 42df23b1f..51664e3d1 100644
--- a/cli/tests/unit/spawn_test.ts
+++ b/cli/tests/unit/spawn_test.ts
@@ -723,8 +723,29 @@ Deno.test(
     const program = `
 const child = await Deno.spawnChild(Deno.execPath(), {
   cwd: Deno.args[0],
+  stdout: "piped",
   args: ["run", "-A", "--unstable", Deno.args[1]],
 });
+const readable = child.stdout.pipeThrough(new TextDecoderStream());
+const reader = readable.getReader();
+// set up an interval that will end after reading a few messages from stdout, 
+// to verify that stdio streams are properly unrefed
+let count = 0;
+let interval;
+interval = setInterval(async () => {
+  count += 1;
+  if (count > 10) {
+    clearInterval(interval);
+    console.log("cleared interval");
+  }
+  const res = await reader.read();
+  if (res.done) {
+    throw new Error("stream shouldn't be done");
+  }
+  if (res.value.trim() != "hello from interval") {
+    throw new Error("invalid message received");
+  }
+}, 120);
 console.log("spawned pid", child.pid);
 child.unref();
 `;
@@ -740,15 +761,19 @@ setInterval(() => {
     // In this subprocess we are spawning another subprocess which has
     // an infite interval set. Following call would never resolve unless
     // child process gets unrefed.
-    const { success, stdout } = await Deno.spawn(Deno.execPath(), {
+    const { success, stdout, stderr } = await Deno.spawn(Deno.execPath(), {
       cwd,
       args: ["run", "-A", "--unstable", programFile, cwd, childProgramFile],
     });
 
     assert(success);
     const stdoutText = new TextDecoder().decode(stdout);
-    const pidStr = stdoutText.split(" ").at(-1);
+    const stderrText = new TextDecoder().decode(stderr);
+    assert(stderrText.length == 0);
+    const [line1, line2] = stdoutText.split("\n");
+    const pidStr = line1.split(" ").at(-1);
     assert(pidStr);
+    assertEquals(line2, "cleared interval");
     const pid = Number.parseInt(pidStr, 10);
     await Deno.remove(cwd, { recursive: true });
     // Child process should have been killed when parent process exits.