package cleanup

// Stack holds deferred cleanup functions and runs them in LIFO order.
// Errors are collected; one cleanup failure does not stop later ones.
type Stack struct {
	fns []func() error
}

// Add registers fn to run on Run().
func (s *Stack) Add(fn func() error) {
	s.fns = append(s.fns, fn)
}

// Run executes all registered functions in reverse order and returns
// every error produced.
func (s *Stack) Run() []error {
	var errs []error
	for i := len(s.fns) - 1; i >= 0; i-- {
		if err := s.fns[i](); err != nil {
			errs = append(errs, err)
		}
	}
	return errs
}