@Test
public void testPutAll() {

    IncrementalSortMap<Integer, String> empty = IncrementalSortMap.create();
    IncrementalSortMap<Integer, String> map = map5();
    empty.putAll(map);
    assertEquals(5, empty.size());
    assertTrue(empty.containsKey(one));
    assertTrue(empty.containsKey(two));
    assertTrue(empty.containsKey(three));
    assertTrue(empty.containsKey(four));
    assertTrue(empty.containsKey(five));
}