svoid test_CompactHashMap() {
  new CompactHashMap<S> map1;
  new HashMap<S> map2;
  
  embedded void check {
    assertEqualsVerbose(map2.size(), map1.size());
    assertEquals(sorted(keys(map2)), sorted(keys(map1)));
    assertEquals(sorted(values(map2)), sorted(values(map1)));
    for (S key : keys(map1))
      assertEquals(map2.get(key), map1.get(key));
    assertNull(map1.get("unknown"));
  }
  
  check();
  repeat 100 {
    repeat 10 {
      putInTwoMaps(map1, map2, aGlobalID(), aGlobalID());
    }
    removeFromTwoMaps(map1, map2, random(keys(map2)));
    check();
  }
}

Began life as a copy of #1013304