@Test
 void addTest() {
   final HopscotchCollection<Integer> hopscotchCollection =
       new HopscotchCollection<>(testVals.size());
   testVals.stream().forEach(hopscotchCollection::add);
   Assert.assertEquals(hopscotchCollection.size(), testVals.size());
   Assert.assertTrue(hopscotchCollection.containsAll(testVals));
 }
 @Test
 void containsTest() {
   final HopscotchCollection<Integer> hopscotchCollection = new HopscotchCollection<>(testVals);
   Assert.assertTrue(hopscotchCollection.containsAll(testVals));
   Assert.assertFalse(hopscotchCollection.contains(notInTestVals));
 }
 @Test
 void createFromCollectionTest() {
   final HopscotchCollection<Integer> hopscotchCollection = new HopscotchCollection<>(testVals);
   Assert.assertEquals(hopscotchCollection.size(), testVals.size());
   Assert.assertTrue(hopscotchCollection.containsAll(testVals));
 }