public void Test_empty_element()
        {
            var xsd    = XsdNamespace;
            var ns     = "uri:test-schema";
            var schema = new Schema("test", ns);

            schema
            .CreateRootElement("DesignModels")
            .CreateElement("Element");

            var outputXsd = new SchemaConverter().Convert(schema);

            outputXsd.Should().NotBeNull();

            var outputXsdStr = outputXsd.Element.ToTestString().FixNewlines().Trim();

            outputXsdStr.Should().Be(@"
<xs:schema elementFormDefault='qualified' targetNamespace='uri:test-schema' xmlns:tns='uri:test-schema' xmlns:xs='http://www.w3.org/2001/XMLSchema'>
    <xs:element name='DesignModels'>
        <xs:complexType>
            <xs:sequence>
                <xs:element maxOccurs='1' minOccurs='0' name='Element'/>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>
".FixNewlines().Trim());
        }