From 6214286757a98b398792b8c4d88c732b45aca302 Mon Sep 17 00:00:00 2001
From: tdakkota <tanc13@yandex.ru>
Date: Mon, 3 Jan 2022 02:08:24 +0300
Subject: [PATCH 1/2] test(json): add UUID decode/encode benchmark

---
 json/uuid_test.go | 56 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 json/uuid_test.go

diff --git a/json/uuid_test.go b/json/uuid_test.go
new file mode 100644
index 000000000..583ecdac4
--- /dev/null
+++ b/json/uuid_test.go
@@ -0,0 +1,56 @@
+package json
+
+import (
+	"testing"
+
+	"github.com/go-faster/jx"
+	"github.com/google/uuid"
+)
+
+func BenchmarkDecodeUUID(b *testing.B) {
+	e := jx.GetEncoder()
+	defer jx.PutEncoder(e)
+
+	u, err := uuid.NewUUID()
+	if err != nil {
+		b.Fatal(err)
+	}
+	EncodeUUID(e, u)
+	data := e.Bytes()
+
+	d := jx.GetDecoder()
+	defer jx.PutDecoder(d)
+
+	b.ReportAllocs()
+	b.SetBytes(int64(len(data)))
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		d.ResetBytes(data)
+		if _, err := DecodeUUID(d); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+
+func BenchmarkEncodeUUID(b *testing.B) {
+	e := jx.GetEncoder()
+	defer jx.PutEncoder(e)
+
+	u, err := uuid.NewUUID()
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	EncodeUUID(e, u)
+	data := e.Bytes()
+
+	b.ReportAllocs()
+	b.SetBytes(int64(len(data)))
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		e.Reset()
+		EncodeUUID(e, u)
+	}
+}

From 8904bc2040b61c2ed2d2129e42dabd0ac1e43d01 Mon Sep 17 00:00:00 2001
From: tdakkota <tanc13@yandex.ru>
Date: Mon, 3 Jan 2022 02:37:29 +0300
Subject: [PATCH 2/2] feat(json): optimize UUID encode/decode

---
 json/uuid.go      | 51 ++++++++++++++++++++++++++++++++++++++++++++---
 json/uuid_test.go | 12 +++++++++++
 2 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/json/uuid.go b/json/uuid.go
index 9690a4c25..9db569066 100644
--- a/json/uuid.go
+++ b/json/uuid.go
@@ -7,14 +7,59 @@ import (
 
 // DecodeUUID decodes UUID from json.
 func DecodeUUID(i *jx.Decoder) (v uuid.UUID, err error) {
-	s, err := i.Str()
+	s, err := i.StrBytes()
 	if err != nil {
 		return v, err
 	}
-	return uuid.Parse(s)
+	return uuid.ParseBytes(s)
 }
 
 // EncodeUUID encodes UUID to json.
 func EncodeUUID(s *jx.Encoder, v uuid.UUID) {
-	s.Str(v.String())
+	const (
+		// Hexed length (16 * 2) + 4 hyphens
+		length       = len(v)*2 + 4
+		quotedLength = length + 2
+	)
+	var dst = [quotedLength]byte{
+		0:                '"',
+		quotedLength - 1: '"',
+	}
+	hexEncode((*[length]byte)(dst[1:length+1]), v)
+	s.Raw(dst[:])
+}
+
+func hexEncode(dst *[36]byte, v uuid.UUID) {
+	const hextable = "0123456789abcdef"
+
+	{
+		dst[0], dst[1] = hextable[v[0]>>4], hextable[v[0]&0x0f]
+		dst[2], dst[3] = hextable[v[1]>>4], hextable[v[1]&0x0f]
+		dst[4], dst[5] = hextable[v[2]>>4], hextable[v[2]&0x0f]
+		dst[6], dst[7] = hextable[v[3]>>4], hextable[v[3]&0x0f]
+	}
+	dst[8] = '-'
+	{
+		dst[9+0], dst[9+1] = hextable[v[4+0]>>4], hextable[v[4+0]&0x0f]
+		dst[9+2], dst[9+3] = hextable[v[4+1]>>4], hextable[v[4+1]&0x0f]
+	}
+	dst[13] = '-'
+	{
+		dst[14+0], dst[14+1] = hextable[v[6+0]>>4], hextable[v[6+0]&0x0f]
+		dst[14+2], dst[14+3] = hextable[v[6+1]>>4], hextable[v[6+1]&0x0f]
+	}
+	dst[18] = '-'
+	{
+		dst[19+0], dst[19+1] = hextable[v[8+0]>>4], hextable[v[8+0]&0x0f]
+		dst[19+2], dst[19+3] = hextable[v[8+1]>>4], hextable[v[8+1]&0x0f]
+	}
+	dst[23] = '-'
+	{
+		dst[24+0], dst[24+1] = hextable[v[10+0]>>4], hextable[v[10+0]&0x0f]
+		dst[24+2], dst[24+3] = hextable[v[10+1]>>4], hextable[v[10+1]&0x0f]
+		dst[24+4], dst[24+5] = hextable[v[10+2]>>4], hextable[v[10+2]&0x0f]
+		dst[24+6], dst[24+7] = hextable[v[10+3]>>4], hextable[v[10+3]&0x0f]
+		dst[24+8], dst[24+9] = hextable[v[10+4]>>4], hextable[v[10+4]&0x0f]
+		dst[24+10], dst[24+11] = hextable[v[10+5]>>4], hextable[v[10+5]&0x0f]
+	}
 }
diff --git a/json/uuid_test.go b/json/uuid_test.go
index 583ecdac4..0f13591c7 100644
--- a/json/uuid_test.go
+++ b/json/uuid_test.go
@@ -5,6 +5,7 @@ import (
 
 	"github.com/go-faster/jx"
 	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
 )
 
 func BenchmarkDecodeUUID(b *testing.B) {
@@ -54,3 +55,14 @@ func BenchmarkEncodeUUID(b *testing.B) {
 		EncodeUUID(e, u)
 	}
 }
+
+func Test_hexEncode(t *testing.T) {
+	a := require.New(t)
+
+	u, err := uuid.NewUUID()
+	a.NoError(err)
+
+	var dst [36]byte
+	hexEncode(&dst, u)
+	a.Equal(u.String(), string(dst[:]))
+}