DateTime <-> DateTimeGraphType mapping (graphql-dotnet#1629)

Author: sungam3r

src/GraphQL.Tests/Bugs/Issue1082.cs

@@ -0,0 +1,41 @@
+using System;
+using GraphQL.Types;
+using Xunit;
+
+namespace GraphQL.Tests.Bugs
+{
+    public class Issue1082 : QueryTestBase<Issue1082Schema>
+    {
+        [Fact]
+        public void Should_Return_DateTime_With_Time_Component()
+        {
+            var query = "{ dateTimeField }";
+            AssertQuerySuccess(query, @"{""dateTimeField"": ""1000-10-10T01:02:03""}");
+        }
+
+        [Fact]
+        public void Should_Return_Date_Without_Time_Component()
+        {
+            var query = "{ dateField }";
+            AssertQuerySuccess(query, @"{""dateField"": ""1000-10-10""}");
+        }
+    }
+
+    public class Issue1082Schema : Schema
+    {
+        public Issue1082Schema()
+        {
+            var query = new ObjectGraphType<Model>();
+            query.Field(f => f.DateTimeField).Resolve(_ => new DateTime(1000, 10, 10, 1, 2, 3));
+            query.Field(f => f.DateField, type: typeof(DateGraphType)).Resolve(_ => new DateTime(1000, 10, 10, 1, 2, 3).Date);
+            Query = query;
+        }
+
+        private class Model
+        {
+            public DateTime DateTimeField { get; set; }
+
+            public DateTime DateField { get; set; }
+        }
+    }
+}

src/GraphQL/Utilities/GraphTypeTypeRegistry.cs

@@ -17,7 +17,7 @@ public static class GraphTypeTypeRegistry
             [typeof(decimal)] = typeof(DecimalGraphType),
             [typeof(string)] = typeof(StringGraphType),
             [typeof(bool)] = typeof(BooleanGraphType),
-            [typeof(DateTime)] = typeof(DateGraphType),
+            [typeof(DateTime)] = typeof(DateTimeGraphType),
             [typeof(DateTimeOffset)] = typeof(DateTimeOffsetGraphType),
             [typeof(TimeSpan)] = typeof(TimeSpanSecondsGraphType),
             [typeof(Guid)] = typeof(IdGraphType),