@Test
public void testHashMap() {

    Map<Smell, Smell> myMap = new HashMap<>();
    myMap.put(first, third);
    assertEquals(third, myMap.get(first));
    assertEquals(third, myMap.get(second));
    assertEquals(third, myMap.get(Smell.copyWithoutParent(first)));
    second.parent = first;
    third.parent = second;
    myMap.put(third, first);
    assertEquals(first, myMap.get(third));
    assertTrue(myMap.containsKey(myMap.keySet().toArray()[0]));
}