@Override
            public void vertexPropertyPropertyChanged(final VertexProperty element, final Property oldValue, final Object setValue) {
                assertThat(element, instanceOf(ReferenceVertexProperty.class));
                assertEquals(label, element.label());
                assertEquals(value, element.value());
                assertEquals("dah", oldValue.value());
                assertEquals("to-change", oldValue.key());
                assertEquals("bah", setValue);
                triggered.set(true);
            }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/EventStrategyProcessTest.java