@Override
    public ScalarOperator visitExistsPredicate(ExistsPredicateOperator predicate, Void context) {
        return shuttleIfUpdate(predicate);
    }
@Test
    void visitExistsPredicate() {
        ExistsPredicateOperator operator = new ExistsPredicateOperator(true, ImmutableList.of());
        {
            ScalarOperator newOperator = shuttle.visitExistsPredicate(operator, null);
            assertEquals(operator, newOperator);
        }
        {
            ScalarOperator newOperator = shuttle2.visitExistsPredicate(operator, null);
            assertEquals(operator, newOperator);
        }
    }