如何在Golang中建立模拟类？

Question

I'm trying to build mock class for unit test in golang; does anyone know how to do that? For example, in the following code slice, I'd like to print FakeMyClass.Object's return value.

package main

import (
    "fmt"
)

type MyClass struct {
}

func (*MyClass) Object() (int) {
    return 0
}

func (mc *MyClass) PrintInfo() {
    fmt.Printf("%v
", mc.Object())
}

type FakeMyClass struct {
    MyClass
}

func (*FakeMyClass) Object() (int) {
    return 1
}

func main() {
    mc := &FakeMyClass{}
    mc.PrintInfo()
}

Answer 1

I prefer to use github.com/stretchr/testify/tree/master/mock

package main

import (
    "fmt"
    "github.com/stretchr/testify/mock"
)

type MyClass struct {
}

func (*MyClass) Object() (int) {
    return 0
}

func (mc *MyClass) PrintInfo() {
    fmt.Printf("%v
", mc.Object())
}

type FakeMyClass struct {
    mock.Mock
}

func (fmc *FakeMyClass) Object() (int) {
    args := fmc.Called()
    return args.Int(0)
}
func (fmc *FakeMyClass) PrintInfo() {
    fmt.Printf("%v
", fmc.Object())
}

func main() {
    mc := &FakeMyClass{}
    mc.On("Object").Return(1)
    mc.PrintInfo()
    //mc.AssertExpectations(t)
}