LOCogroup cogroup = (LOCogroup)lp.getSuccessors(loada).get(0);
List<RequiredFields> cogroupRequiredFields = cogroup.getRequiredFields();
assertTrue(cogroupRequiredFields.size() == 1);
requiredField = cogroupRequiredFields.get(0);
assertTrue(requiredField.needNoFields() == true);
assertTrue(requiredField.needAllFields() == false);
assertTrue(requiredField.getFields() == null);
//check that the foreach required fields contain [<0, 1>]
LOForEach foreach = (LOForEach)lp.getLeaves().get(0);