From 1db0d51ab2ef90e23e64f77486a0f4d6e15e2c5b Mon Sep 17 00:00:00 2001
From: Robert Nagy <ronagy@icloud.com>
Date: Wed, 13 May 2020 21:14:30 +0200
Subject: [PATCH] stream: forward writableObjectMode

Duplex did not properly forward writableObjectMode.

Fixes: https://github.com/nodejs/node/issues/33388

PR-URL: https://github.com/nodejs/node/pull/33390
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
---
 lib/_stream_duplex.js                     |  2 ++
 test/parallel/test-stream-duplex-props.js | 31 +++++++++++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 test/parallel/test-stream-duplex-props.js

diff --git a/lib/_stream_duplex.js b/lib/_stream_duplex.js
index ced361c8d60898..2b92959a2c3d6c 100644
--- a/lib/_stream_duplex.js
+++ b/lib/_stream_duplex.js
@@ -75,6 +75,8 @@ ObjectDefineProperties(Duplex.prototype, {
     ObjectGetOwnPropertyDescriptor(Writable.prototype, 'writable'),
   writableHighWaterMark:
     ObjectGetOwnPropertyDescriptor(Writable.prototype, 'writableHighWaterMark'),
+  writableObjectMode:
+    ObjectGetOwnPropertyDescriptor(Writable.prototype, 'writableObjectMode'),
   writableBuffer:
     ObjectGetOwnPropertyDescriptor(Writable.prototype, 'writableBuffer'),
   writableLength:
diff --git a/test/parallel/test-stream-duplex-props.js b/test/parallel/test-stream-duplex-props.js
new file mode 100644
index 00000000000000..aa6b23125a9d9d
--- /dev/null
+++ b/test/parallel/test-stream-duplex-props.js
@@ -0,0 +1,31 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+const { Duplex } = require('stream');
+
+{
+  const d = new Duplex({
+    objectMode: true,
+    highWaterMark: 100
+  });
+
+  assert.strictEqual(d.writableObjectMode, true);
+  assert.strictEqual(d.writableHighWaterMark, 100);
+  assert.strictEqual(d.readableObjectMode, true);
+  assert.strictEqual(d.readableHighWaterMark, 100);
+}
+
+{
+  const d = new Duplex({
+    readableObjectMode: false,
+    readableHighWaterMark: 10,
+    writableObjectMode: true,
+    writableHighWaterMark: 100
+  });
+
+  assert.strictEqual(d.writableObjectMode, true);
+  assert.strictEqual(d.writableHighWaterMark, 100);
+  assert.strictEqual(d.readableObjectMode, false);
+  assert.strictEqual(d.readableHighWaterMark, 10);
+}