@Test
    public void testFilterExpression() throws IOException {
        try (SerializationTester t = new SerializationTester("testFilterExpression")) {
            t.assertMatch(new RegexPredicateNode("^foo.*", new AttributeNode("attributeA")));
            t.assertMatch(new RegexPredicateNode("^foo.*", null));
        }
    }
Tests serialization compatibility across Java and C++. The comparison is performed by comparing serialized Java
object graphs with the content of specific binary files. C++ unit tests serializes
identical data structures into these files.
Note: This test relies heavily on proper implementation of {@link Object#equals(Object)}!
searchlib/src/test/java/com/yahoo/searchlib/aggregation/GroupingSerializationTest.java