public override void SerializeAsXml(XmlWriter xmlWriter)
        {
            if (xmlWriter == null)
            {
                throw new ArgumentNullException($"{nameof(xmlWriter)} cannot be null.");
            }

            if (this.expressionStr == null)
            {
                this.expressionStr = LinqTestInput.FilterInputExpression(this.Expression.Body.ToString());
            }


            xmlWriter.WriteStartElement("Description");
            xmlWriter.WriteCData(this.Description);
            xmlWriter.WriteEndElement();
            xmlWriter.WriteStartElement("Expression");
            xmlWriter.WriteCData(expressionStr);
            xmlWriter.WriteEndElement();
            if (this.errorMessage != null)
            {
                xmlWriter.WriteStartElement("ErrorMessage");
                xmlWriter.WriteCData(this.errorMessage);
                xmlWriter.WriteEndElement();
            }
        }