@Test
    @LoadGraphWith(MODERN)
    public void g_withSideEffectXa__marko_666_noone_blahX_V_groupXaX_byXnameX_byXoutE_label_foldX_capXaX() {
        final Map<String, List<Object>> m = new HashMap<>();
        m.put("marko", new ArrayList<>(Collections.singleton(666)));
        m.put("noone", new ArrayList<>(Collections.singleton("blah")));

        final Traversal<Vertex, Map<String, List<Object>>> traversal = get_g_withSideEffectXa__marko_666_noone_blahX_V_groupXaX_byXnameX_byXoutE_label_foldX_capXaX(m);
        printTraversalForm(traversal);
        final Map<String, List<Object>> map = traversal.next();
        assertEquals(7, map.size());
        assertEquals(Collections.singleton("blah"), new HashSet<>(map.get("noone")));
        assertEquals(new HashSet<>(Arrays.asList("created", "knows", 666)), new HashSet<>(map.get("marko")));
        assertEquals(Collections.singleton("created"), new HashSet<>(map.get("josh")));
        assertEquals(Collections.singleton("created"), new HashSet<>(map.get("peter")));
        assertEquals(Collections.emptySet(), new HashSet<>(map.get("vadas")));
        assertEquals(Collections.emptySet(), new HashSet<>(map.get("lop")));
        assertEquals(Collections.emptySet(), new HashSet<>(map.get("ripple")));
        checkSideEffects(traversal.asAdmin().getSideEffects(), "a", HashMap.class);
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/GroupTest.java