func slowCaller(ctx context.Context) error {
	sl := time.NewTimer(time.Second)
	defer sl.Stop()

	select {
	case <-sl.C:
	case <-ctx.Done():
		return ctx.Err()
	}

	return nil
}

func TestCacheCtx(t *testing.T) {
	cache := New[time.Time]()
	t.Parallel()
	cache.InitOnce(2*time.Second, Opts{},
		func(ctx context.Context) (time.Time, error) {
			return time.Now(), slowCaller(ctx)
		},
	)