if err != nil {
		return err
	}

	wk, err := workers.New(workerSize)
	if err != nil {
		// invalid worker size.
		return err
	}

	ctx, cancelCause := context.WithCancelCause(ctx)
	defer cancelCause(nil)

	results := make(chan itemOrErr[ObjectInfo], workerSize)
	go func() {
		prefixes := r.Prefix.F()
		if len(prefixes) == 0 {
			prefixes = []string{""}
		}