// Each group is a List of items, each item has a list of factory args.
    List<List<List<Object>>> argGroups = new ArrayList<>();
    argGroups.add(ImmutableList.of(args, equalArgs));
    EqualsTester tester =
        new EqualsTester(
            /* itemReporter= */ item -> {
              List<Object> factoryArgs = argGroups.get(item.groupNumber).get(item.itemNumber);
              return factory.getName()