NewWriterF with sync.Pool

多次写入，需要扩容时速度提升

binary/writer.go

@@ -4,12 +4,12 @@ import (
 	"bytes"
 	"encoding/binary"
 	"encoding/hex"
+	"sync"
 )
 
 type Writer bytes.Buffer
 
-/*
+var bufferPool = sync.Pool{
-var bufferPool = sync.Pool{ // todo sync.Pool 无法通过单元测试
 	New: func() interface{} {
 		return new(bytes.Buffer)
 	},
@@ -27,7 +27,6 @@ func PutBuffer(buf *bytes.Buffer) {
 		bufferPool.Put(buf)
 	}
 }
-*/
 
 func NewWriter() *Writer {
 	return new(Writer)
@@ -40,9 +39,11 @@ func PutWriter(w *Writer) {
 */
 
 func NewWriterF(f func(writer *Writer)) []byte {
-	w := new(bytes.Buffer)
+	w := NewBuffer()
 	f((*Writer)(w))
-	return w.Bytes()
+	b := append([]byte(nil), w.Bytes()...)
+	PutBuffer(w)
+	return b
 }
 
 func (w *Writer) Write(b []byte) {

binary/writer_test.go

@@ -10,8 +10,8 @@ import (
 )
 
 func NewWriterFOld(f func(writer *Writer)) []byte {
-	w := (*Writer)(new(bytes.Buffer))
+	w := new(bytes.Buffer)
-	f(w)
+	f((*Writer)(w))
 	return w.Bytes()
 }
 
@@ -53,8 +53,8 @@ func TestNewWriterF(t *testing.T) {
 	wg.Wait()
 }
 
-func BenchmarkNewWriterFOld256(b *testing.B) {
+func BenchmarkNewWriterFOld128(b *testing.B) {
-	test := make([]byte, 256)
+	test := make([]byte, 128)
 	rand.Read(test)
 	b.StartTimer()
 	b.RunParallel(func(pb *testing.PB) {
@@ -66,8 +66,8 @@ func BenchmarkNewWriterFOld256(b *testing.B) {
 	})
 }
 
-func BenchmarkNewWriterF256(b *testing.B) {
+func BenchmarkNewWriterF128(b *testing.B) {
-	test := make([]byte, 256)
+	test := make([]byte, 128)
 	rand.Read(test)
 	b.StartTimer()
 	b.RunParallel(func(pb *testing.PB) {
@@ -79,27 +79,31 @@ func BenchmarkNewWriterF256(b *testing.B) {
 	})
 }
 
-func BenchmarkNewWriterFOld1024(b *testing.B) {
+func BenchmarkNewWriterFOld128_3(b *testing.B) {
-	test := make([]byte, 1024)
+	test := make([]byte, 128)
 	rand.Read(test)
 	b.StartTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			NewWriterFOld(func(w *Writer) {
 				w.Write(test)
+				w.Write(test)
+				w.Write(test)
 			})
 		}
 	})
 }
 
-func BenchmarkNewWriterF1024(b *testing.B) {
+func BenchmarkNewWriterF128_3(b *testing.B) {
-	test := make([]byte, 1024)
+	test := make([]byte, 128)
 	rand.Read(test)
 	b.StartTimer()
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
 			NewWriterF(func(w *Writer) {
 				w.Write(test)
+				w.Write(test)
+				w.Write(test)
 			})
 		}
 	})