List catIds = cg.collectFromCategoryLinks( new IdBlock() );
List catIds = cg.eachLinkedCategory( new IdBlock() );
    private void check_cgc_ids(List ids)    {        for (CategoryGroup cg: (List<CategoryGroup>) list)        {            List catIds = cg.collectFromCategoryLinks( new IdBlock() );            assertTrue( "And our categories weren't there",                     catIds.containsAll( ids ));        }    }