improve variable names and add Refs

Author: thisalihassan

lib/buffer.js

@@ -1171,30 +1171,30 @@ function _fill(buf, value, offset, end, encoding) {
 }
 
 Buffer.prototype.write = function write(string, offset, length, encoding) {
-  const len = this.length;
+  const bufferLength = this.length;
   // Buffer#write(string);
   if (offset === undefined) {
-    return utf8Write(this, string, 0, len);
+    return utf8Write(this, string, 0, bufferLength);
   }
   // Buffer#write(string, encoding)
   if (length === undefined && typeof offset === 'string') {
     encoding = offset;
-    length = len;
+    length = bufferLength;
     offset = 0;
 
   // Buffer#write(string, offset[, length][, encoding])
   } else {
-    validateOffset(offset, 'offset', 0, len);
+    validateOffset(offset, 'offset', 0, bufferLength);
 
-    const remaining = len - offset;
+    const remaining = bufferLength - offset;
 
     if (length === undefined) {
       length = remaining;
     } else if (typeof length === 'string') {
       encoding = length;
       length = remaining;
     } else {
-      validateOffset(length, 'length', 0, len);
+      validateOffset(length, 'length', 0, bufferLength);
       if (length > remaining)
         length = remaining;
     }
@@ -1258,6 +1258,7 @@ function swap(b, n, m) {
 }
 
 Buffer.prototype.swap16 = function swap16() {
+  // Ref: https://github.com/nodejs/node/pull/61871#discussion_r2889557696
   // For Buffer.length <= 32, it's generally faster to
   // do the swap in javascript. For larger buffers,
   // dropping down to the native code is faster.
@@ -1274,6 +1275,7 @@ Buffer.prototype.swap16 = function swap16() {
 };
 
 Buffer.prototype.swap32 = function swap32() {
+  // Ref: https://github.com/nodejs/node/pull/61871#discussion_r2889557696
   // For Buffer.length <= 32, it's generally faster to
   // do the swap in javascript. For larger buffers,
   // dropping down to the native code is faster.
@@ -1292,9 +1294,12 @@ Buffer.prototype.swap32 = function swap32() {
 };
 
 Buffer.prototype.swap64 = function swap64() {
+  // Ref: https://github.com/nodejs/node/pull/61871#discussion_r2889557696
   // For Buffer.length < 48, it's generally faster to
   // do the swap in javascript. For larger buffers,
   // dropping down to the native code is faster.
+  // Threshold differs from swap16/swap32 (<=32) because swap64's
+  // crossover is between 40 and 48 (native wins at 48, loses at 40).
   const len = TypedArrayPrototypeGetLength(this);
   if (len % 8 !== 0)
     throw new ERR_INVALID_BUFFER_SIZE('64-bits');