From 5d7556ad3d556e09fce30c5645eb63692d7921bf Mon Sep 17 00:00:00 2001
From: tidwall <joshbaker77@gmail.com>
Date: Sat, 16 Feb 2019 14:50:53 -0700
Subject: [PATCH] Valid json optimization

Added ~20% performance boost be removing extra allocation when
Valid() is called with a json string.
---
 gjson.go      |  2 +-
 gjson_gae.go  |  4 ++++
 gjson_ngae.go |  8 ++++++++
 gjson_test.go | 20 ++++++++++++++++++++
 4 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/gjson.go b/gjson.go
index 2c9325f..7722ad9 100644
--- a/gjson.go
+++ b/gjson.go
@@ -2038,7 +2038,7 @@ func validnull(data []byte, i int) (outi int, ok bool) {
 //  value := gjson.Get(json, "name.last")
 //
 func Valid(json string) bool {
-	_, ok := validpayload([]byte(json), 0)
+	_, ok := validpayload(stringBytes(json), 0)
 	return ok
 }
 
diff --git a/gjson_gae.go b/gjson_gae.go
index 3a2b251..6a316e5 100644
--- a/gjson_gae.go
+++ b/gjson_gae.go
@@ -8,3 +8,7 @@ func getBytes(json []byte, path string) Result {
 func fillIndex(json string, c *parseContext) {
 	// noop. Use zero for the Index value.
 }
+
+func stringBytes(s string) []byte {
+	return []byte(s)
+}
diff --git a/gjson_ngae.go b/gjson_ngae.go
index 59e944b..f606581 100644
--- a/gjson_ngae.go
+++ b/gjson_ngae.go
@@ -67,3 +67,11 @@ func fillIndex(json string, c *parseContext) {
 		}
 	}
 }
+
+func stringBytes(s string) []byte {
+	return *(*[]byte)(unsafe.Pointer(&reflect.SliceHeader{
+		Data: (*reflect.StringHeader)(unsafe.Pointer(&s)).Data,
+		Len:  len(s),
+		Cap:  len(s),
+	}))
+}
diff --git a/gjson_test.go b/gjson_test.go
index 31bd31f..d718ba0 100644
--- a/gjson_test.go
+++ b/gjson_test.go
@@ -1431,3 +1431,23 @@ func TestArrayValues(t *testing.T) {
 	}
 
 }
+
+func BenchmarkValid(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Valid(complicatedJSON)
+	}
+}
+
+func BenchmarkValidBytes(b *testing.B) {
+	complicatedJSON := []byte(complicatedJSON)
+	for i := 0; i < b.N; i++ {
+		ValidBytes(complicatedJSON)
+	}
+}
+
+func BenchmarkGoStdlibValidBytes(b *testing.B) {
+	complicatedJSON := []byte(complicatedJSON)
+	for i := 0; i < b.N; i++ {
+		json.Valid(complicatedJSON)
+	}
+}