@Override
        public void map(final Vertex vertex, final MapEmitter emitter) {
            assertFalse(vertex.property("v1").isPresent());
            assertFalse(vertex.property("v2").isPresent());
            assertTrue(vertex.property("v3").isPresent());
            assertTrue(vertex.property("name").isPresent());
            assertEquals(3, IteratorUtils.count(vertex.properties()));
            assertEquals(3, IteratorUtils.count(vertex.values()));
        }
Javadoc for {@code ConcurrentSkipListSet} includes this little note: "Beware that, unlike in most
collections, the size method is not a constant-time operation." Doing a traversal of elements will yield
the correct count. Java 11 upgrade seemed to force this failure consistently.
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/computer/GraphComputerTest.java