assertFalse( "retainAll(TIntSet) failed (same set): " + set,
set.retainAll( set ) );
// Contains all the original elements
assertTrue( set.toString(), set.containsAll( ints ) );
assertTrue( retain_set.toString(), retain_set.containsAll( to_retain ) );
assertTrue( "retainAll(Collection<?>) failed: " + set,
set.retainAll( retain_list ) );
// Contains just the expected elements
assertFalse( set.toString(), set.containsAll( ints ) );