fib_test.go

package main

import "testing"

// func benchmarkFib(i int, b *testing.B) {
// 	// run the Fib function b.N times
// 	for n := 0; n < b.N; n++ {
// 		Fib(i)
// 	}
// }

// func BenchmarkFib1(b *testing.B)  { benchmarkFib(1, b) }
// func BenchmarkFib2(b *testing.B)  { benchmarkFib(2, b) }
// func BenchmarkFib3(b *testing.B)  { benchmarkFib(3, b) }
// func BenchmarkFib10(b *testing.B) { benchmarkFib(10, b) }
// func BenchmarkFib20(b *testing.B) { benchmarkFib(20, b) }
// func BenchmarkFib40(b *testing.B) { benchmarkFib(40, b) }

var result int

func BenchmarkFibComplete(b *testing.B) {
	var r int
	for n := 0; n < b.N; n++ {
		// always record the result of Fib to prevent
		// the compiler eliminating the function call.
		r = Fib(10)
	}
	// always store the result to a package level variable
	// so the compiler cannot eliminate the Benchmark itself.
	result = r
}