1、单元测试 + Mock 测试 + 基准测试

加上 -gcflags=all=-l gomonkey 库就不会受到内联优化的干扰

package main

import "strconv"

type ST struct {
}

func Hello() string {
	return "Hello"
}

func MockFunction(id int) string {
	return "MockFunction:" + strconv.Itoa(id)
}

func (t *ST) MockMethod(id int) string {
	return "MockMethod:" + strconv.Itoa(id)
}

package main

import (
	"fmt"
	"reflect"
	"testing"

	"github.com/agiledragon/gomonkey"
	"github.com/smartystreets/goconvey/convey"
	"github.com/stretchr/testify/assert"
)

func TestMain(m *testing.M) {
	// Before
	fmt.Println("Before")
	m.Run()
	// After
	fmt.Println("After")
}

func TestHello(t *testing.T) {
	assert.Equal(t, "Hello", Hello())
}

func TestMockFunctionAndMockMethod(t *testing.T) {
	convey.Convey("MockFunction", t, func() {
                // mock func
		patches := gomonkey.ApplyFunc(MockFunction, func(int) string {
			return "mock-function"
		})
		defer patches.Reset()
		assert.Equal(t, "mock-function", MockFunction(10086))
                // mock method
		patches = gomonkey.ApplyMethod(reflect.TypeOf(&ST{}), "MockMethod", func(t *ST, id int) string {
			return "mock-method"
		})
		defer patches.Reset()
		st := &ST{}
		assert.Equal(t, "mock-method", st.MockMethod(10086))
	})
}

func BenchmarkRand(b *testing.B) {
	// init
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		rand.Intn(1000)
	}
}

func BenchmarkParallel(b *testing.B) {
	// init
	b.ResetTimer()
	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			rand.Intn(1000)
		}
	})
}