Correctly escape as for the spec.

Updated benchmarks

Fixes #13

Author: mcollina

README.md

@@ -1,20 +1,20 @@
 # fast-json-stringify  [![Build Status](https://travis-ci.org/mcollina/fast-json-stringify.svg)](https://travis-ci.org/mcollina/fast-json-stringify)
 
-__fast-json-stringify__ is x1-5 times faster than `JSON.stringify()`.
+__fast-json-stringify__ is x1-4 times faster than `JSON.stringify()`.
 It is particularly suited if you are sending small JSON payloads, the
 advantages reduces on large payloads.
 
 Benchmarks:
 
 ```
-JSON.stringify array x 3,500 ops/sec ±0.91% (85 runs sampled)
-fast-json-stringify array x 4,456 ops/sec ±1.68% (87 runs sampled)
-JSON.stringify long string x 13,395 ops/sec ±0.88% (91 runs sampled)
-fast-json-stringify long string x 95,488 ops/sec ±1.04% (90 runs sampled)
-JSON.stringify short string x 5,059,316 ops/sec ±0.86% (92 runs sampled)
-fast-json-stringify short string x 12,219,967 ops/sec ±1.16% (91 runs sampled)
-JSON.stringify obj x 1,763,980 ops/sec ±1.30% (88 runs sampled)
-fast-json-stringify obj x 5,085,148 ops/sec ±1.56% (89 runs sampled)
+JSON.stringify array x 3,679 ops/sec ±1.01% (85 runs sampled)
+fast-json-stringify array x 4,618 ops/sec ±1.64% (87 runs sampled)
+JSON.stringify long string x 13,303 ops/sec ±1.01% (89 runs sampled)
+fast-json-stringify long string x 13,489 ops/sec ±0.88% (90 runs sampled)
+JSON.stringify short string x 4,974,749 ops/sec ±1.14% (86 runs sampled)
+fast-json-stringify short string x 11,030,700 ops/sec ±0.82% (89 runs sampled)
+JSON.stringify obj x 1,774,593 ops/sec ±1.07% (90 runs sampled)
+fast-json-stringify obj x 4,976,369 ops/sec ±1.00% (89 runs sampled)
 ```
 
 #### Table of contents:

index.js

@@ -16,7 +16,6 @@ function build (schema, options) {
   code += `
     ${$asString.toString()}
     ${$asStringSmall.toString()}
-    ${$asStringLong.toString()}
     ${$asNumber.toString()}
     ${$asNull.toString()}
     ${$asBoolean.toString()}
@@ -89,35 +88,24 @@ function $asString (str) {
   if (str.length < 42) {
     return $asStringSmall(str)
   } else {
-    return $asStringLong(str)
+    return JSON.stringify(str)
   }
 }
 
-function $asStringLong (str) {
-  var result = ''
-  var l = str.length
-  var i
-
-  for (;(i = str.indexOf('"')) >= 0 && i < l;) {
-    result += str.slice(0, i) + '\\"'
-    str = str.slice(i + 1)
-    l = str.length
-  }
-
-  if (l > 0) {
-    result += str
-  }
-
-  return '"' + result + '"'
-}
-
+// magically escape strings for json
+// relying on their charCodeAt
+// everything below 32 needs JSON.stringify()
+// 34 and 92 happens all the time, so we
+// have a fast case for them
 function $asStringSmall (str) {
   var result = ''
   var last = 0
   var l = str.length
-  for (var i = 0; i < l; i++) {
-    if (str[i] === '"') {
-      result += str.slice(last, i) + '\\"'
+  var point = 255
+  for (var i = 0; i < l && point >= 32; i++) {
+    point = str.charCodeAt(i)
+    if (point === 34 || point === 92) {
+      result += str.slice(last, i) + '\\' + str[i]
       last = i + 1
     }
   }
@@ -126,7 +114,7 @@ function $asStringSmall (str) {
   } else {
     result += str.slice(last)
   }
-  return '"' + result + '"'
+  return point < 32 ? JSON.stringify(str) : '"' + result + '"'
 }
 
 function $asRegExp (reg) {

test/basic.test.js

@@ -50,6 +50,11 @@ buildTest({
   type: 'string'
 }, 'hello world')
 
+buildTest({
+  title: 'string',
+  type: 'string'
+}, 'hello\nworld')
+
 buildTest({
   title: 'string with quotes',
   type: 'string'