golang 字符串拼接方法对比分析

package test
import (
    "bytes"
    "fmt"
    "strings"
    "testing"
)
func BenchmarkFmtSprintf(b *testing.B) {
    for i := 0; i < b.N; i++ {
        s := fmt.Sprintf("%s%s", "abcdefghijklmnopqrstuvwxyz", "123456789")
        fmt.Errorf(s)
    }
}
func BenchmarkAdd(b *testing.B) {
    for i := 0; i < b.N; i++ {
        s := "abcdefghijklmnopqrstuvwxyz" +"123456789"
        fmt.Errorf(s)
    }
}
func BenchmarkStringsJoin(b *testing.B) {
    for i := 0; i < b.N; i++ {
        s := strings.Join([]string{"abcdefghijklmnopqrstuvwxyz","123456789"}, "")
        fmt.Errorf(s)
    }
}
func BenchmarkBuffer(b *testing.B) {
    for i := 0; i < b.N; i++ {
        buf := bytes.Buffer{}
        buf.WriteString("abcdefghijklmnopqrstuvwxyz")
        buf.WriteString("123456789")
        fmt.Errorf(buf.String())
    }
}
func BenchmarkBuilder(b *testing.B) {
    for i := 0; i < b.N; i++ {
        builder := strings.Builder{}
        builder.WriteString("abcdefghijklmnopqrstuvwxyz")
        builder.WriteString("123456789")
        fmt.Errorf(builder.String())
    }
}

go test string_test.go -benchmem -bench=".*"

package test
import (
    "bytes"
    "fmt"
    "strings"
    "testing"
)
func BenchmarkAdd2(b *testing.B) {
    s:= "abcdefghijklmnopqrstuvwxyz"
    for i := 0; i < b.N; i++ {
        s += "abcdefghijklmnopqrstuvwxyz"
    }
    fmt.Errorf(s)
}
func BenchmarkBuffer2(b *testing.B) {
    buf := bytes.Buffer{}
    for i := 0; i < b.N; i++ {
        buf.WriteString("abcdefghijklmnopqrstuvwxyz")
    }
    fmt.Errorf(buf.String())
}
func BenchmarkBuilder2(b *testing.B) {
    builder := strings.Builder{}
    for i := 0; i < b.N; i++ {
        builder.WriteString("abcdefghijklmnopqrstuvwxyz")
    }
    fmt.Errorf(builder.String())
}

go test string2_test.go -benchmem -bench=".*"