stream: fix readable stream as async iterator function

Since v19.2 it's not possible to use readableStreams as async iterators (confirmed bug). This patch fixes the problem by reading the Stream.Duplex property from 'streams/duplex' instead of 'streams/legacy' module Fixes: #46141 PR-URL: #46147 Reviewed-By: Benjamin Gruenbaum <[email protected]> Reviewed-By: Robert Nagy <[email protected]> Reviewed-By: Matteo Collina <[email protected]>
nodejs · Jan 20, 2023 · 5d0946a · 5d0946a
1 parent babe6d7
commit 5d0946a
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diff --git a/lib/stream/promises.js b/lib/stream/promises.js
@@ -13,6 +13,8 @@ const {
 const { pipelineImpl: pl } = require('internal/streams/pipeline');
 const { finished } = require('internal/streams/end-of-stream');
 
+require('stream');
+
 function pipeline(...streams) {
   return new Promise((resolve, reject) => {
     let signal;

diff --git a/test/parallel/test-stream3-pipeline-async-iterator.js b/test/parallel/test-stream3-pipeline-async-iterator.js
@@ -0,0 +1,27 @@
+/* eslint-disable node-core/require-common-first, require-yield */
+'use strict';
+const { pipeline } = require('node:stream/promises');
+{
+  // Ensure that async iterators can act as readable and writable streams
+  async function* myCustomReadable() {
+    yield 'Hello';
+    yield 'World';
+  }
+
+  const messages = [];
+  async function* myCustomWritable(stream) {
+    for await (const chunk of stream) {
+      messages.push(chunk);
+    }
+  }
+
+  (async () => {
+    await pipeline(
+      myCustomReadable,
+      myCustomWritable,
+    );
+    // Importing here to avoid initializing streams
+    require('assert').deepStrictEqual(messages, ['Hello', 'World']);
+  })()
+  .then(require('../common').mustCall());
+}