presto-hive/src/main/java/io/prestosql/plugin/hive/HiveAnalyzeProperties.java/HiveAnalyzeProperties/decodePartitionLists
class HiveAnalyzeProperties:    private static List<List<String>> decodePartitionLists(Object object)
    {
        if (object == null) {
            return null;
        }

        // replace null partition value with hive default partition
        return ((Collection<?>) object).stream()
                .peek(partition -> throwIfNull(partition, "partitions"))
                .map(partition -> ((Collection<?>) partition).stream()
                        .map(name -> firstNonNull((String) name, HIVE_DEFAULT_DYNAMIC_PARTITION))
                        .collect(toImmutableList()))
                .distinct()
                .collect(toImmutableList());
    }