teamai-test/.teamai/skills/common/golang-samber-do/references/testing.md

Testing with samber/do

Container Cloning

Clone containers for isolated tests:

func TestUserService(t *testing.T) {
    // Create test container by cloning main container
    testInjector := mainInjector.Clone()

    // Override with mocks
    mockDB := &MockDatabase{}
    do.OverrideValue(testInjector, mockDB)

    // Test with mocked dependencies
    service := do.MustInvoke[UserService](testInjector)
    // ... test code
}

Reusable Test Helpers

func SetupTestContainer(t *testing.T) do.Injector {
    injector := do.New()

    do.Provide(injector, func(i do.Injector) (Database, error) {
        return &MockDatabase{}, nil
    })

    return injector
}

Quick Reference

Testing & Overrides

Function	Purpose
injector.Clone()	Clone container for testing
injector.CloneWithOpts()	Clone with custom options
do.Override[T]()	Replace service (use in tests)
do.OverrideNamed[T]()	Replace named service
do.OverrideValue[T]()	Replace value service
do.OverrideNamedValue[T]()	Replace named value
do.OverrideTransient[T]()	Replace transient factory
do.OverrideNamedTransient[T]()	Replace named transient factory