presto-spi/src/main/java/io/prestosql/spi/type/TypeSignature.java/TypeSignature/rowType
class TypeSignature:    public static TypeSignature rowType(List<TypeSignatureParameter> fields)
    {
        checkArgument(fields.stream().allMatch(parameter -> parameter.getKind() == ParameterKind.NAMED_TYPE), "Parameters for ROW type must be NAMED_TYPE parameters");

        return new TypeSignature(StandardTypes.ROW, fields);
    }