From 78ff21e144922cdab1084dcf19048e12dcebb60a Mon Sep 17 00:00:00 2001
From: Ethan Shea <ethan.shea1@gmail.com>
Date: Sun, 27 Jun 2021 23:44:07 -0700
Subject: [PATCH] Fix nullable struct serialization

Addresses #360
---
 .../Serialization/SerializationTestHelper.cs   |  5 +++++
 .../Serialization/SerializationTests.cs        | 18 ++++++++++++++++++
 .../ObjectNodeDeserializer.cs                  |  7 +++++--
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/YamlDotNet.Test/Serialization/SerializationTestHelper.cs b/YamlDotNet.Test/Serialization/SerializationTestHelper.cs
index 9f43770e3..272245aae 100644
--- a/YamlDotNet.Test/Serialization/SerializationTestHelper.cs
+++ b/YamlDotNet.Test/Serialization/SerializationTestHelper.cs
@@ -141,6 +141,11 @@ public enum EnumExample
         Two
     }
 
+    public struct StructExample
+    {
+        public int Value { get; set; }
+    }
+
     public enum SByteEnum : sbyte { Default, Sbyte }
     public enum ByteEnum : byte { Default, Byte }
     public enum Int16Enum : short { Default, Short }
diff --git a/YamlDotNet.Test/Serialization/SerializationTests.cs b/YamlDotNet.Test/Serialization/SerializationTests.cs
index e27c66ba3..613a259e4 100644
--- a/YamlDotNet.Test/Serialization/SerializationTests.cs
+++ b/YamlDotNet.Test/Serialization/SerializationTests.cs
@@ -183,6 +183,24 @@ public void RoundtripNullableEnums(EnumExample? value)
             result.Should().Be(value);
         }
 
+        [Fact]
+        public void RoundtripNullableStructWithValue()
+        {
+            var value = new StructExample { Value = 2 };
+
+            var result = DoRoundtripFromObjectTo<StructExample?>(value);
+
+            result.Should().Be(value);
+        }
+
+        [Fact]
+        public void RoundtripNullableStructWithoutValue()
+        {
+            var result = DoRoundtripFromObjectTo<StructExample?>(null);
+
+            result.Should().Be(null);
+        }
+
         [Fact]
         public void SerializeCircularReference()
         {
diff --git a/YamlDotNet/Serialization/NodeDeserializers/ObjectNodeDeserializer.cs b/YamlDotNet/Serialization/NodeDeserializers/ObjectNodeDeserializer.cs
index 4c44b9fb4..559a29f46 100644
--- a/YamlDotNet/Serialization/NodeDeserializers/ObjectNodeDeserializer.cs
+++ b/YamlDotNet/Serialization/NodeDeserializers/ObjectNodeDeserializer.cs
@@ -47,11 +47,14 @@ bool INodeDeserializer.Deserialize(IParser parser, Type expectedType, Func<IPars
                 return false;
             }
 
-            value = objectFactory.Create(expectedType);
+            // Strip off the nullable type, if present. This is needed for nullable structs.
+            var implementationType = Nullable.GetUnderlyingType(expectedType) ?? expectedType;
+
+            value = objectFactory.Create(implementationType);
             while (!parser.TryConsume<MappingEnd>(out var _))
             {
                 var propertyName = parser.Consume<Scalar>();
-                var property = typeDescriptor.GetProperty(expectedType, null, propertyName.Value, ignoreUnmatched);
+                var property = typeDescriptor.GetProperty(implementationType, null, propertyName.Value, ignoreUnmatched);
                 if (property == null)
                 {
                     parser.SkipThisAndNestedEvents();