Mocking HTTP Request inside methods in Golang

main.go

package main

import (
	"io"
	"log"
	"net/http"
)

type httpClient interface {
	Get(string) (*http.Response, error)
}

type myStruct struct {
	httpClient httpClient
}

// example method
func (m myStruct) getExample() ([]byte, error) {
	resp, err := m.httpClient.Get("https://example.com")
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	return io.ReadAll(resp.Body)
}

func main() {
	log.Print("inicializando")
}

main_test.go

package main

import (
	"fmt"
	"io"
	"net/http"
	"strings"
	"testing"
)

func TestOne(t *testing.T) {

	client := new(mockedClient)

	s := myStruct{httpClient: client}

	client.On(
		"Get", "https://example.com",
	).Return(
		&http.Response{
			StatusCode: 200,
			Body:       io.NopCloser(strings.NewReader(`{"userId": 2,"id": 2,"title": "test title2","body": "test body2"}`)),
		}, nil,
	)

	body, err := s.getExample()
	if err != nil {
		println(err.Error())

	}
	fmt.Println(body)
}

mock.go

package main

import (
	"net/http"

	"github.com/stretchr/testify/mock"
)

type mockedClient struct {
	mock.Mock
}

func (m mockedClient) Get(url string) (*http.Response, error) {
	args := m.Called(url)
	if args.Get(0) == nil {
		return nil, args.Error(1)
	} else {
		return args.Get(0).(*http.Response), args.Error(1)
	}
}