@SuppressFBWarnings(value = "EI_EXPOSE_REP", justification = "lookupConstraints is ImmutableList")
  public List<LookupConstraint> getLookupConstraints() {
    return lookupConstraints;
  }
@Test
  public void shouldReturnNonKeyConstraintIntGreater() {
    // Given:
    final Expression expression = new ComparisonExpression(
            Type.GREATER_THAN,
            new UnqualifiedColumnReferenceExp(ColumnName.of("K")),
            new IntegerLiteral(1)
    );
    QueryFilterNode filterNode = new QueryFilterNode(
            NODE_ID,
            source,
            expression,
            metaStore,
            ksqlConfig,
            false,
            plannerOptions
    );

    // When:
    final List<LookupConstraint> keys = filterNode.getLookupConstraints();

    // Then:
    assertThat(keys.size(), is(1));
    assertThat(keys.get(0), instanceOf(NonKeyConstraint.class));
  }