From 273ae636f579ae3f8b63985702abe4e28382b1dd Mon Sep 17 00:00:00 2001
From: "Kamat, Trivikram" <16024985+trivikr@users.noreply.github.com>
Date: Wed, 27 May 2026 17:27:50 -0700
Subject: [PATCH] stream: settle pending broadcast reads on return

Resolve pending next() calls when broadcast consumers are returned,
so the promise does not remain pending after iterator cleanup.

Fixes: https://github.com/nodejs/node/issues/63519

Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>
Assisted-by: openai:gpt-5.5
---
 lib/internal/streams/iter/broadcast.js            |  1 +
 test/parallel/test-stream-iter-broadcast-basic.js | 13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/lib/internal/streams/iter/broadcast.js b/lib/internal/streams/iter/broadcast.js
index e6a404729d6e0b..aa83c9636598ea 100644
--- a/lib/internal/streams/iter/broadcast.js
+++ b/lib/internal/streams/iter/broadcast.js
@@ -165,6 +165,7 @@ class BroadcastImpl {
 
     function detach() {
       state.detached = true;
+      state.resolve?.({ __proto__: null, done: true, value: undefined });
       state.resolve = null;
       state.reject = null;
       if (self.#deleteConsumer(state)) {
diff --git a/test/parallel/test-stream-iter-broadcast-basic.js b/test/parallel/test-stream-iter-broadcast-basic.js
index ab2c81304ec2ac..32c1750fb4cbfd 100644
--- a/test/parallel/test-stream-iter-broadcast-basic.js
+++ b/test/parallel/test-stream-iter-broadcast-basic.js
@@ -161,6 +161,18 @@ async function testCancelWithReason() {
   assert.strictEqual(result.message, 'cancelled');
 }
 
+async function testPendingNextSettlesAfterReturn() {
+  const { broadcast: bc } = broadcast();
+  const iter = bc.push()[Symbol.asyncIterator]();
+
+  const pendingNext = iter.next();
+  await iter.return();
+
+  const result = await pendingNext;
+  assert.strictEqual(result.done, true);
+  assert.strictEqual(result.value, undefined);
+}
+
 // =============================================================================
 // Writer fail detaches consumers
 // =============================================================================
@@ -254,6 +266,7 @@ Promise.all([
   testCancelWithoutReason(),
   testCancelWithReason(),
   testCancelWithFalsyReason(),
+  testPendingNextSettlesAfterReturn(),
   testFailDetachesConsumers(),
   testWriterFailIdempotent(),
   testLateJoinerSeesBufferedData(),