string 连接基准测试

go-strings-bench.go

package test

import (
	"fmt"
	"strconv"
	"testing"
)

const (
	str        = "abc"
	sep        = "123"
	intA int   = 123456
	intB int64 = 1098765
)

func BenchmarkFmtreflect(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = fmt.Sprintf("%v%v%v%v%v%v", str, str, str, sep, sep, sep)
	}
}

// string fmt 连接，只含 string
func BenchmarkFmt(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = fmt.Sprintf("%s%s%s%s%s%s", str, str, str, sep, sep, sep)
	}
}

// string + 连接，只含 string
func BenchmarkPlus(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = str + str + str + sep + sep + sep
	}
}

func BenchmarkFmtWithInt(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = fmt.Sprintf("%d%s%s%s%s%d", intA, str, str, sep, sep, intB)
	}
}

// string + 连接带数字
func BenchmarkPlusWithInt(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = strconv.Itoa(intA) + str + str + sep + sep + strconv.FormatInt(intB, 10)
	}
}

// goos: darwin
// goarch: amd64
// pkg: xx
// BenchmarkFmtreflect-4    	 5000000	       275 ns/op	      32 B/op	       1 allocs/op
// BenchmarkFmt-4           	 5000000	       276 ns/op	      32 B/op	       1 allocs/op
// BenchmarkPlus-4          	2000000000	         0.35 ns/op	       0 B/op	       0 allocs/op
// BenchmarkFmtWithInt-4    	 5000000	       305 ns/op	      32 B/op	       1 allocs/op
// BenchmarkPlusWithInt-4   	10000000	       133 ns/op	      16 B/op	       2 allocs/op
// PASS
// coverage: 0.0% of statements
// ok  	xx	7.491s
// Success: Benchmarks passed.