Add tests for data contract serialization of System.Type

test/IntegrationTests/MSTest.IntegrationTests/Parameterized tests/DataRowTests.cs

@@ -167,7 +167,9 @@ public async Task DataRowsShouldHandleNonSerializableValues()
         // Assert
         VerifyE2E.TestsDiscovered(
             testCases,
-            "DataRowNonSerializable");
+            "DataRowNonSerializable (System.String)",
+            "DataRowNonSerializable (System.Int32)",
+            "DataRowNonSerializable (DataRowTestProject.DataRowTests_DerivedClass)");
 
         VerifyE2E.TestsPassed(
             testResults,

test/UnitTests/MSTestAdapter.PlatformServices.UnitTests/Helpers/DataSerializationHelperTests.cs

@@ -81,4 +81,32 @@
         actual[0]!.Equals(source).Should().BeTrue();
     }
 #endif
+
+    public void DataSerializerShouldRoundTripSystemType()
+    {
+        Type[] source = [typeof(Console), typeof(DataSerializationHelperTests), typeof(DataSerializationHelper)];
+
+        foreach (Type type in source)
+        {
+            object?[]? actual = DataSerializationHelper.Deserialize(DataSerializationHelper.Serialize([type]));
+
+            actual!.Length.Should().Be(1);
+            actual[0].Should().Be(type);
+        }
+    }
+
+    public void DataSerializerShouldRoundTripMixedPayloadIncludingSystemType()
+    {
+        object?[] source = [typeof(string), 42, "hello", null, new DateTime(638450000000000000)];
+
+        object?[]? actual = DataSerializationHelper.Deserialize(DataSerializationHelper.Serialize(source));
+
+        actual.Should().NotBeNull();
+        actual!.Length.Should().Be(source.Length);
+        actual[0].Should().Be(typeof(string));
+        actual[1].Should().Be(42);
+        actual[2].Should().Be("hello");
+        actual[3].Should().BeNull();
+        actual[4].Should().Be(source[4]);
+    }
 }