Extension differences

UnitTestFhirNet19.cs

using System;
using System.Linq;
using Hl7.Fhir.Introspection;
using Hl7.Fhir.Model;
using Hl7.Fhir.Serialization;
using Xunit;

namespace TestProject1
{
    public class UnitTest1
    {
        [Fact]
        public void Test1()
        {
            var element = BaseFhirParser.Inspector.FindClassMappingByType("Extension");
            var valueProp = element.PropertyMappings.First(x => x.Name == "value");

            Assert.Equal(ChoiceType.DatatypeChoice, valueProp.Choice);
            Assert.Equal(49, valueProp.FhirType.Length);
        }
    }
}

UnitTestFhirNet20.cs

using System;
using System.Linq;
using System.Reflection;
using Hl7.Fhir.Introspection;
using Hl7.Fhir.Model;
using Xunit;

namespace TestProject2
{
    public class UnitTest1
    {
        [Fact]
        public void Test1()
        {
            var extension = GetModelInspector().FindClassMapping("Extension");
            var valueProp = extension.PropertyMappings.First(x => x.Name == "value");

            Assert.Equal(ChoiceType.DatatypeChoice, valueProp.Choice);

            // Why is this now 1?
            Assert.Equal(1, valueProp.FhirType.Length);
        }

        private static ModelInspector GetModelInspector()
        {
            string methodName = "GetStructureDefinitionSummaryProvider";
            MethodInfo modelInspectorMethod = typeof(ModelInfo).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Static);

            if (modelInspectorMethod == null)
            {
                throw new MissingMethodException(nameof(ModelInfo), methodName);
            }

            return (ModelInspector)modelInspectorMethod.Invoke(null, null);
        }
    }
}