From: Feross Aboukhadijeh <feross@feross.org>
Date: Wed, 4 Nov 2020 21:17:24 +0000 (-1000)
Subject: avoid unnecessary buffer copy
X-Git-Url: https://zoso.dev/?a=commitdiff_plain;h=411bd9a88158c488c99b624882c563f777442c63;p=buffer.git

avoid unnecessary buffer copy
---

diff --git a/index.js b/index.js
index 96a4acb..7a0e9c2 100644
--- a/index.js
+++ b/index.js
@@ -407,10 +407,11 @@ Buffer.concat = function concat (list, length) {
   const buffer = Buffer.allocUnsafe(length)
   let pos = 0
   for (i = 0; i < list.length; ++i) {
-    const buf = list[i]
+    let buf = list[i]
     if (isInstance(buf, Uint8Array)) {
       if (pos + buf.length > buffer.length) {
-        Buffer.from(buf).copy(buffer, pos)
+        if (!Buffer.isBuffer(buf)) buf = Buffer.from(buf)
+        buf.copy(buffer, pos)
       } else {
         Uint8Array.prototype.set.call(
           buffer,