Refactor some code to reduce code size

Author: Ruben Bridgewater

README.md

@@ -90,7 +90,7 @@ To handle protocol errors (this is very unlikely to happen) gracefully you shoul
 
 ## Contribute
 
-The parser is highly optimized but there may still be further optimizations possible. 
+The parser is highly optimized but there may still be further optimizations possible.
 
 ```
 npm install

lib/parser.js

@@ -65,6 +65,7 @@ function parseStringNumbers (parser) {
  */
 function convertBufferRange (parser, start, end) {
   // If returnBuffers is active, all return values are returned as buffers besides numbers and errors
+  parser.offset = end + 2
   if (parser.optionReturnBuffers === true) {
     return parser.buffer.slice(start, end)
   }
@@ -82,10 +83,10 @@ function parseSimpleStringViaOffset (parser) {
   var start = parser.offset
   var offset = parser.offset
   var length = parser.buffer.length
+  var buffer = parser.buffer
 
   while (offset < length) {
-    if (parser.buffer[offset++] === 10) { // \r\n
-      parser.offset = offset
+    if (buffer[offset++] === 10) { // \r\n
       return convertBufferRange(parser, start, offset - 2)
     }
   }
@@ -140,10 +141,7 @@ function parseBulkString (parser) {
     return
   }
 
-  var offsetBegin = parser.offset
-  parser.offset = offsetEnd + 2
-
-  return convertBufferRange(parser, offsetBegin, offsetEnd)
+  return convertBufferRange(parser, parser.offset, offsetEnd)
 }
 
 /**
@@ -284,23 +282,22 @@ function JavascriptRedisParser (options) {
 function concatBulkString (parser) {
   var list = parser.bufferCache
   // The first chunk might contain the whole bulk string including the \r
-  var end = parser.totalChunkSize - parser.bigStrSize === -1
   var chunks = list.length
-  if (end) {
-    parser.offset = 1
+  var offset = parser.bigStrSize - parser.totalChunkSize
+  parser.offset = offset
+  if (offset === 1) {
     if (chunks === 2) {
       return list[0].toString('utf8', parser.bigOffset, list[0].length - 1)
     }
   } else {
-    parser.offset = parser.bigStrSize - parser.totalChunkSize
     chunks++
   }
   var res = list[0].toString('utf8', parser.bigOffset)
   for (var i = 1; i < chunks - 2; i++) {
     // We are only safe to fully add up elements that are neither the first nor any of the last two elements
     res += list[i].toString()
   }
-  res += list[i].toString('utf8', 0, end ? list[i].length - 1 : parser.offset - 2)
+  res += list[i].toString('utf8', 0, offset === 1 ? list[i].length - 1 : offset - 2)
   return res
 }
 
@@ -357,17 +354,15 @@ JavascriptRedisParser.prototype.execute = function (buffer) {
     if (bufferPool.length < newLength) { // We can't rely on the chunk size
       bufferPool = new Buffer(newLength)
     }
-    var newBuffer = bufferPool
-    this.buffer.copy(newBuffer, 0, this.offset, oldLength)
-    buffer.copy(newBuffer, remainingLength, 0, buffer.length)
-    this.buffer = newBuffer.slice(0, newLength)
+    this.buffer.copy(bufferPool, 0, this.offset, oldLength)
+    buffer.copy(bufferPool, remainingLength, 0, buffer.length)
+    this.buffer = bufferPool.slice(0, newLength)
     this.offset = 0
   } else if (this.totalChunkSize + buffer.length >= this.bigStrSize) {
     this.bufferCache.push(buffer)
     // The returned type might be Array * (42) and in that case we can't improve the parsing currently
     if (this.optionReturnBuffers === false && this.buffer[this.offset] === 36) {
       this.returnReply(concatBulkString(this))
-      this.bigOffset = 0
       this.buffer = buffer
     } else { // This applies for arrays too
       this.buffer = concatBuffer(this, this.totalChunkSize + buffer.length)