chore: initial plan

2026-07-24 16:23:24 +07:00
commit d47a07af46
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+# Mocking and Test Fixtures
+
+## Mocks with testify/mock
+
+Create interfaces for your dependencies, then mock them.
+
+> For the full testify/mock API (argument matchers, call modifiers, verification), see the `samber/cc-skills-golang@golang-stretchr-testify` skill.
+
+```go
+// Define the interface
+type Database interface {
+    GetUser(id string) (*User, error)
+    CreateUser(user *User) error
+}
+
+// Mock implementation
+type MockDatabase struct {
+    mock.Mock
+}
+
+func (m *MockDatabase) GetUser(id string) (*User, error) {
+    args := m.Called(id)
+    if args.Get(0) == nil {
+        return nil, args.Error(1)
+    }
+    return args.Get(0).(*User), args.Error(1)
+}
+
+func (m *MockDatabase) CreateUser(user *User) error {
+    args := m.Called(user)
+    return args.Error(0)
+}
+
+// Usage in tests
+func TestService_GetUser(t *testing.T) {
+    is := assert.New(t)
+
+    mockDB := new(MockDatabase)
+    service := NewService(mockDB)
+
+    expectedUser := &User{ID: "1", Name: "John"}
+    mockDB.On("GetUser", "1").Return(expectedUser, nil)
+
+    user, err := service.GetUser("1")
+
+    is.NoError(err)
+    is.Equal(expectedUser, user)
+    mockDB.AssertExpectations(t)
+}
+
+func TestService_GetUser_NotFound(t *testing.T) {
+    is := assert.New(t)
+
+    mockDB := new(MockDatabase)
+    service := NewService(mockDB)
+
+    mockDB.On("GetUser", "999").Return(nil, ErrNotFound)
+
+    user, err := service.GetUser("999")
+
+    is.Error(err)
+    is.ErrorIs(err, ErrNotFound)
+    is.Nil(user)
+    mockDB.AssertExpectations(t)
+}
+```
+
+## Mock Organization
+
+For larger codebases, organize mocks alongside the code they mock:
+
+```go
+// user_service.go
+type UserService struct {
+    db    Database
+    email EmailService
+}
+type Database interface {
+    GetUser(id string) (*User, error)
+    CreateUser(user *User) error
+}
+type EmailService interface {
+    SendWelcomeEmail(to string) error
+}
+```
+
+```go
+// user_service_test.go
+package mypackage_test
+
+import (
+    "testing"
+    "github.com/stretchr/testify/assert"
+    "github.com/stretchr/testify/mock"
+    "path/to/mypackage"
+)
+
+// MockDatabase implements mypackage.Database
+type MockDatabase struct {
+    mock.Mock
+}
+func (m *MockDatabase) GetUser(id string) (*mypackage.User, error) {
+    args := m.Called(id)
+    if args.Get(0) == nil { return nil, args.Error(1) }
+    return args.Get(0).(*mypackage.User), args.Error(1)
+}
+func (m *MockDatabase) CreateUser(user *mypackage.User) error {
+    return m.Called(user).Error(0)
+}
+
+// MockEmailService implements mypackage.EmailService
+type MockEmailService struct {
+    mock.Mock
+}
+func (m *MockEmailService) SendWelcomeEmail(to string) error {
+    return m.Called(to).Error(0)
+}
+
+func TestUserService_CreateUser(t *testing.T) {
+    mockDB := new(MockDatabase)
+    mockEmail := new(MockEmailService)
+    service := mypackage.NewUserService(mockDB, mockEmail)
+
+    user := &mypackage.User{Name: "Test", Email: "test@example.com"}
+    mockDB.On("CreateUser", user).Return(nil)
+    mockEmail.On("SendWelcomeEmail", "test@example.com").Return(nil)
+
+    err := service.CreateUser(user)
+
+    assert.NoError(t, err)
+    mockDB.AssertExpectations(t)
+    mockEmail.AssertExpectations(t)
+}
+```
+
+## Test Fixtures
+
+Create reusable test data in a separate package or file:
+
+```go
+package fixtures
+
+import "time"
+
+var (
+    DefaultUser = &User{
+        ID:        "user-123",
+        Name:      "Jane Doe",
+        Email:     "jane@example.com",
+        CreatedAt: time.Date(2024, 1, 1, 0, 0, 0, 0, time.UTC),
+    }
+
+    AdminUser = &User{
+        ID:        "admin-1",
+        Name:      "Admin User",
+        Email:     "admin@example.com",
+        Role:      "admin",
+        CreatedAt: time.Date(2024, 1, 1, 0, 0, 0, 0, time.UTC),
+    }
+)
+
+func NewUser(name, email string) *User {
+    return &User{
+        ID:        "user-" + uuid.New().String(),
+        Name:      name,
+        Email:     email,
+        CreatedAt: time.Now(),
+    }
+}
+```
+
+## Time Mocking
+
+Use `clockwork` to test time-dependent code without `time.Sleep()`:
+
+```go
+import (
+    "testing"
+    "time"
+    "github.com/jonboulle/clockwork"
+    "github.com/stretchr/testify/assert"
+)
+
+func TestScheduler_AddJob(t *testing.T) {
+    is := assert.New(t)
+
+    fakeClock := clockwork.NewFakeClock()
+    scheduler := NewScheduler(fakeClock)
+
+    job := &Job{ID: "1", RunAt: time.Now().Add(1 * time.Hour)}
+    scheduler.AddJob(job)
+
+    is.Equal(1, scheduler.PendingCount())
+
+    // Advance fake time
+    fakeClock.Advance(2 * time.Hour)
+
+    is.Equal(0, scheduler.PendingCount())
+}
+```
+
+Install clockwork:
+
+```bash
+go get github.com/jonboulle/clockwork
+```