@Override
    public <K, V> Predicate<K, V> optimize(Predicate<K, V> predicate, IndexRegistry indexes) {
        return predicate;
    }
@Test
    public void optimize_returnsOriginalPredicate() {
        EmptyOptimizer emptyOptimizer = new EmptyOptimizer();
        Predicate predicate = mock(Predicate.class);
        IndexRegistry indexes = mock(IndexRegistry.class);

        Predicate result = emptyOptimizer.optimize(predicate, indexes);
        assertSame(predicate, result);
    }