Add getter tests to TypeFieldsTests

Author: mythz

src/ServiceStack.Text/TypeFields.cs

@@ -78,7 +78,7 @@ public static TypeFields Get(Type type)
             return instance;
         }
 
-        public Type Type;
+        public Type Type { get; protected set; }
 
         public readonly Dictionary<string, PropertyGetterDelegate> PublicGetters =
             new Dictionary<string, PropertyGetterDelegate>(PclExport.Instance.InvariantComparerIgnoreCase);

tests/ServiceStack.Text.Tests/TypeFieldReflectorTests.cs

@@ -0,0 +1,35 @@
+using NUnit.Framework;
+
+namespace ServiceStack.Text.Tests
+{
+    public class TypeFieldsTests
+    {
+        (string s, int i, long l, double d) CreateValueTuple() =>
+            ("foo", 1, 2, 3.3);
+
+        [Test]
+        public void Can_cache_ValueTuple_field_accessors()
+        {
+            var typeFields = TypeFields.Get(typeof((string s, int i, long l, double d)));
+
+            var oTuple = (object)CreateValueTuple();
+
+            typeFields.GetPublicSetterRef("Item1")(ref oTuple, "bar");
+            typeFields.GetPublicSetterRef("Item2")(ref oTuple, 10);
+            typeFields.GetPublicSetterRef("Item3")(ref oTuple, 20L);
+            typeFields.GetPublicSetterRef("Item4")(ref oTuple, 4.4d);
+
+            Assert.That(typeFields.GetPublicGetter("Item1")(oTuple), Is.EqualTo("bar"));
+            Assert.That(typeFields.GetPublicGetter("Item2")(oTuple), Is.EqualTo(10));
+            Assert.That(typeFields.GetPublicGetter("Item3")(oTuple), Is.EqualTo(20));
+            Assert.That(typeFields.GetPublicGetter("Item4")(oTuple), Is.EqualTo(4.4));
+
+            var tuple = ((string s, int i, long l, double d))oTuple;
+
+            Assert.That(tuple.s, Is.EqualTo("bar"));
+            Assert.That(tuple.i, Is.EqualTo(10));
+            Assert.That(tuple.l, Is.EqualTo(20));
+            Assert.That(tuple.d, Is.EqualTo(4.4));
+        }
+    }
+}