optimize Buffer#toString()

From
https://github.com/nodejs/io.js/commit/8350f3a3a291fcd19df3261c3db3fe07c
7590bb7

diff --git a/index.js b/index.js
index 5f66a3fbe6271f88dc851d7dd391b993cf82dc0b..fac60da0a7f479506e12fafc3f36c083c0508b95 100644 (file)
--- a/index.js
+++ b/index.js
@@ -336,8 +336,7 @@ Buffer.byteLength = byteLength
 Buffer.prototype.length = undefined
 Buffer.prototype.parent = undefined
 
-// toString(encoding, start=0, end=buffer.length)
-Buffer.prototype.toString = function toString (encoding, start, end) {
+function slowToString (encoding, start, end) {
   var loweredCase = false
 
   start = start | 0
@@ -380,6 +379,13 @@ Buffer.prototype.toString = function toString (encoding, start, end) {
   }
 }
 
+Buffer.prototype.toString = function toString () {
+  var length = this.length | 0
+  if (length === 0) return ''
+  if (arguments.length === 0) return utf8Slice(this, 0, length)
+  return slowToString.apply(this, arguments)
+}
+
 Buffer.prototype.equals = function equals (b) {
   if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
   if (this === b) return true