strings_benchmark.go

package main

import (
	"fmt"
	"math/rand"
	"strings"
	"testing"
)

var (
	a string
	b string
)

func init() {
	a = randomString(10)
	b = randomString(10)
}

func main() {
	result := testing.Benchmark(BenchmarkSprintf)
	fmt.Printf("%-20s\t%s\n", "BenchmarkSprintf", result)

	result = testing.Benchmark(BenchmarkStringsJoin)
	fmt.Printf("%-20s\t%s\n", "BenchmarkStringsJoin", result)
	/**
	Prints...
	BenchmarkSprintf    	16642424	        70.95 ns/op
	BenchmarkStringsJoin	53095192	        22.19 ns/op
	 */
}

func BenchmarkSprintf(bm *testing.B) {
	for i := 0; i < bm.N; i++ {
		_ = fmt.Sprintf("%s:%s", a, b)
	}
}

func BenchmarkStringsJoin(bm *testing.B) {
	for i := 0; i < bm.N; i++ {
		_ = strings.Join([]string{a, b}, ":")
	}
}

// Helper to generate a random string of length n
func randomString(n int) string {
	letters := []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
	b := make([]rune, n)
	for i := range b {
		b[i] = letters[rand.Intn(len(letters))]
	}
	return string(b)
}