mockgen -source=./infra/db.go -destination=./mock/mock_repository.go -package=mock
//去db.go找接口
//去mock目錄下生成mock_repository.go
//生成的包名叫mock

mockgen database/sql/driver Conn,Driver
// 表示要對database/sql/driver 包下的Conn和Driver接口生成mock

// Automatically generated by MockGen. DO NOT EDIT!
// Source: ./infra/db.go (interfaces: Repository)

package mock

import (
    gomock "github.com/golang/mock/gomock"
)

// MockRepository is a mock of Repository interface
type MockRepository struct {
    ctrl     *gomock.Controller
    recorder *MockRepositoryMockRecorder
}

// MockRepositoryMockRecorder is the mock recorder for MockRepository
type MockRepositoryMockRecorder struct {
    mock *MockRepository
}

// NewMockRepository creates a new mock instance
func NewMockRepository(ctrl *gomock.Controller) *MockRepository {
    mock := &MockRepository{ctrl: ctrl}
    mock.recorder = &MockRepositoryMockRecorder{mock}
    return mock
}

// EXPECT returns an object that allows the caller to indicate expected use
func (m *MockRepository) EXPECT() *MockRepositoryMockRecorder {
    return m.recorder
}

// Create mocks base method
func (m *MockRepository) Create(key string, value []byte) error {
    ret := m.ctrl.Call(m, "Create", key, value)
    ret0, _ := ret[0].(error)
    return ret0
}

// Create indicates an expected call of Create
func (mr *MockRepositoryMockRecorder) Create(key, value interface{}) *gomock.Call {
   return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Create", reflect.TypeOf((*MockRepository)(nil).Create), key, value)
}

// Retrieve mocks base method
func (m *MockRepository) Retrieve(key string) ([]byte, error) {
   ret := m.ctrl.Call(m, "Retrieve", key)
   ret0, _ := ret[0].([]byte)
   ret1, _ := ret[1].(error)
   return ret0, ret1
}

// Retrieve indicates an expected call of Retrieve
func (mr *MockRepositoryMockRecorder) Retrieve(key interface{}) *gomock.Call {
   return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Retrieve", reflect.TypeOf((*MockRepository)(nil).Retrieve), key)
}

// Update mocks base method
func (m *MockRepository) Update(key string, value []byte) error {
   ret := m.ctrl.Call(m, "Update", key, value)
   ret0, _ := ret[0].(error)
   return ret0
}

// Update indicates an expected call of Update
func (mr *MockRepositoryMockRecorder) Update(key, value interface{}) *gomock.Call {
   return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Update", reflect.TypeOf((*MockRepository)(nil).Update), key, value)
}

// Delete mocks base method
func (m *MockRepository) Delete(key string) error {
   ret := m.ctrl.Call(m, "Delete", key)
   ret0, _ := ret[0].(error)
   return ret0
}

// Delete indicates an expected call of Delete
func (mr *MockRepositoryMockRecorder) Delete(key interface{}) *gomock.Call {
   return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Delete", reflect.TypeOf((*MockRepository)(nil).Delete), key)
}

type Movie strcut {
    Name string
    Type string
    Score int
}

//定義一個interface類型
type Repository struct {
    // 傳進去一個空指針movie，希望返回的時候把movie填上內容，然后返回error
    // 但是真實的Retrieve要連數據庫，太重了。用GoMock雖然能攔截調用，但GoMock只能決定返回值
    // （比如只能返回nil），卻不能真正往movie里面填數據
    Retrieve(key string, movie *movie) error
}    

// ---------------------------------------------------------
func TestDemo(t *testing.T) {
    Convey("test demo", t, func() {
        Convey("retrieve movie", func() {
            ctrl := NewController(t)
            defer ctrl.Finish()
            mockRepo := mock_db.NewMockRepository(ctrl)
            mockRepo.EXPECT().Retrieve(Any(), Any()).Return(nil)
            Patch(redisrepo.GetInstance, func() Repository {
                return mockRepo
            })
            defer UnpatchAll()
            PatchInstanceMethod(reflect.TypeOf(mockRepo), "Retrieve", func(_ *mock_db.MockRepository, name string, movie *Movie) error {
                movie = &Movie{Name: name, Type: "Love", Score: 95}
                return nil
            })
            repo := redisrepo.GetInstance()
            var movie *Movie
            err := repo.Retrieve("Titanic", movie)
            So(err, ShouldBeNil)
            So(movie.Name, ShouldEqual, "Titanic")
            So(movie.Type, ShouldEqual, "Love")
            So(movie.Score, ShouldEqual, 95)
        })
        ...
    })
}

var GetUserHost = "https://account.wps.cn"
// 默認情況下，GetUser會調用https://account.wps.cn/p/auth/check這個真實的接口
// 但在測試時不想依賴外部網絡，所以要“偽造”一個接口服務器
func GetUser(wpssid, xff string) *User {
    url := fmt.Sprintf("%s/p/auth/check", GetUserHost)
    user := client.POST(url, ...)
    return user
}

func TestGetUser(t *testing.T) {
    // 用httptest.NewServer啟動了一個本地HTTP服務器
    // 它只實現一個接口POST /p/auth/check，并且返回一個固定的JSON（模擬線上接口的返回）
    svr := httptest.NewServer(func () http.HandlerFunc {
        r := gin.Default()
        r.POST("/p/auth/check", func(c *gin.Context) {
            c.JSON(http.StatusOK, gin.H{
                "result":      "ok",
                "companyid":   1,
                "nickname":    "test-account",
                "account":     "123***789@test.com",
                "phonenumber": "123***789",
                "pic":         "https://pic.test.com",
                "status":      "active",
                "userid":      currentUserID,
            })
        })

        return r.ServeHTTP
    })

    defer svr.Close()    //測試結束后關閉這個臨時服務器
    GetUserHost = svr.URL

    user := GetUser("test-wps-id", "")
    ...
}

# 匹配當前目錄下*_test.go命令的文件，執行每一個測試函數
go test -v

# 執行 calc_test.go 文件中的所有測試函數
go test -v calc_test.go calc.go

# 指定特定的測試函數（其中：-count=1用于跳過緩存）
go test -v -run TestAdd calc_test.go calc.go -count=1

#調試單元測試文件。運行命令時，當前目錄應為項目根目錄。
go test ./...     #運行所有包單元測試文件
go test ${包名}     #運行指定包的單元測試文件
go test ${指定路徑}    #運行指定路徑的單元測試文件

go test -v -covermode=set -coverprofile=cover.out -coverpkg=./...

其中，
-covermode 有三種模式：
? set 語句是否執行，默認模式
? count 每個語句執行次數
? atomic 類似于count，表示并發程序中的精確技術
-coverprofile是統計信息保存的文件。

//（1）查看每個函數的覆蓋情況
go tool cover -func=cover.out

//（2）使用網頁方式
go tool cover -html=cover.out