From f3ab106750b1e461f0dfca0d2495897bff76ec24 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Tue, 13 Feb 2018 00:58:22 +0100
Subject: [PATCH] buffer: remove obsolete NaN check
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These two NaN entries are not necessary and we can safely remove them.

PR-URL: https://github.com/nodejs/node/pull/18744
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Yuta Hiroto <hello@about-hiroppy.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
---
 lib/buffer.js                            | 7 ++-----
 test/parallel/test-buffer-arraybuffer.js | 3 +++
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/buffer.js b/lib/buffer.js
index 95d41206c67142..fa966b27a7a009 100644
--- a/lib/buffer.js
+++ b/lib/buffer.js
@@ -377,10 +377,7 @@ function fromArrayBuffer(obj, byteOffset, length) {
   } else {
     // convert length to non-negative integer
     length = +length;
-    // Check for NaN
-    if (length !== length) {
-      length = 0;
-    } else if (length > 0) {
+    if (length > 0) {
       if (length > maxLength)
         throw new errors.RangeError('ERR_BUFFER_OUT_OF_BOUNDS', 'length');
     } else {
@@ -403,7 +400,7 @@ function fromObject(obj) {
   }
 
   if (obj.length !== undefined || isAnyArrayBuffer(obj.buffer)) {
-    if (typeof obj.length !== 'number' || obj.length !== obj.length) {
+    if (typeof obj.length !== 'number') {
       return new FastBuffer();
     }
     return fromArrayLike(obj);
diff --git a/test/parallel/test-buffer-arraybuffer.js b/test/parallel/test-buffer-arraybuffer.js
index 5ecf0279e02c88..41af1eecbea4b2 100644
--- a/test/parallel/test-buffer-arraybuffer.js
+++ b/test/parallel/test-buffer-arraybuffer.js
@@ -148,3 +148,6 @@ b.writeDoubleBE(11.11, 0, true);
     message: '"length" is outside of buffer bounds'
   });
 }
+
+// Test an array like entry with the length set to NaN.
+assert.deepStrictEqual(Buffer.from({ length: NaN }), Buffer.alloc(0));