From 6eb53e5611da070c00f2a2acd6e09fda7fd202a4 Mon Sep 17 00:00:00 2001
From: Matteo Collina <hello@matteocollina.com>
Date: Tue, 27 Jun 2017 19:03:00 +0200
Subject: [PATCH] stream: avoid possible slow path w UInt8Array
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A chunk validity checks verifie if a chunk is a UInt8Array.
We should defer it as it might be very expensive in older Node.js
platforms.

PR-URL: https://github.com/nodejs/node/pull/13956
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
---
 lib/_stream_writable.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 78ab13d9063c67..334f492ba68eef 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -248,7 +248,7 @@ function validChunk(stream, state, chunk, cb) {
 Writable.prototype.write = function(chunk, encoding, cb) {
   var state = this._writableState;
   var ret = false;
-  var isBuf = Stream._isUint8Array(chunk) && !state.objectMode;
+  var isBuf = !state.objectMode && Stream._isUint8Array(chunk);
 
   if (isBuf && Object.getPrototypeOf(chunk) !== Buffer.prototype) {
     chunk = Stream._uint8ArrayToBuffer(chunk);