@Test
 public void toMap() {
   MutableList<Integer> integers = SingletonListTest.newWith(1);
   MutableMap<Integer, Integer> map =
       integers.toMap(Functions.getIntegerPassThru(), Functions.getIntegerPassThru());
   Verify.assertContainsAll(map.keySet(), 1);
   Verify.assertContainsAll(map.values(), 1);
 }
 @Test
 public void toSortedListBy() {
   MutableList<Integer> integers = SingletonListTest.newWith(1);
   MutableList<Integer> list = integers.toSortedListBy(Functions.getIntegerPassThru());
   Assert.assertEquals(FastList.newListWith(1), list);
   Assert.assertNotSame(integers, list);
 }
 @Test
 public void betweenExclusiveNumber() {
   assertBetweenExclusive(Predicates.betweenExclusive(1, 3));
   assertBetweenExclusive(
       Predicates.attributeBetweenExclusive(Functions.getIntegerPassThru(), 1, 3));
 }
 @Override
 @Test(expected = UnsupportedOperationException.class)
 public void getIfAbsentPutWithKey() {
   this.newMapWithKeysValues(1, 1, 2, 2, 3, 3)
       .getIfAbsentPutWithKey(4, Functions.getIntegerPassThru());
 }