@Test
    @LoadGraphWith(MODERN)
    public void g_V_constantXnullX() {
        final Traversal<Vertex, Void> traversal = get_g_V_constantXnullX();
        printTraversalForm(traversal);
        assertEquals(Arrays.asList(null, null, null, null, null, null), traversal.toList());
    }
@author Matt Frantz (http://github.com/mhfrantz)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/ConstantTest.java