@Test
    public void shouldApplyLabelOnElement() {
        final Element e = mock(Element.class);
        when(e.label()).thenReturn("knows");

        assertEquals("knows", T.label.apply(e));
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/structure/TTest.java