package ut

// Deopter describes an action that can be opted-out. This can be used in combination with defer to clean up
type Deopter interface {
	Add(...DeoptFunc)
	Deopt()
	Invoke() error
}

// DeoptFunc describes the action signature for the Deopter.
type DeoptFunc func() error

// NewDeopter creates a deopter for the functions supplied.
func NewDeopter(fn ...DeoptFunc) Deopter {
	return &deopter{fn}
}

type deopter struct {
	fn []DeoptFunc
}

func (d *deopter) Add(fn ...DeoptFunc) {
	d.fn = append(d.fn, fn...)
}

func (d *deopter) Deopt() {
	d.fn = nil
}

func (d *deopter) Invoke() error {
	var err error
	for _, fn := range d.fn {
		err = ErrCombine(err, fn())
	}
	return err
}