@Test
 public void tree_ret_1() {
   int[] keys = {1, 2, 3, 4, 5};
   RangeIndex rIndex = makeRangeIndex(2);
   add(rIndex, keys);
   boolean b = rIndex.insert(intToRecord(3));
   assertFalse(b);
   b = rIndex.insert(intToRecord(9));
   assertTrue(b);
 }