format(
              "estimated size of spliterator after trySplit (%s) is larger than original size (%s)",
              spliterator.estimateSize(), originalSize));
    }
    if (trySplit != null) {
      if (trySplit.estimateSize() > originalSize) {
        fail(
            format(
                "estimated size of trySplit result (%s) is larger than original size (%s)",
                trySplit.estimateSize(), originalSize));