From 816c3a24924a4594a173afbb44728e8cb8b06520 Mon Sep 17 00:00:00 2001
From: Brendan Burns <bburns@microsoft.com>
Date: Sat, 24 Oct 2020 08:36:10 -0700
Subject: [PATCH] Fix deserialization for Nullable types.

---
 YamlDotNet.Test/Serialization/SerializationTests.cs       | 8 ++++++++
 .../NodeDeserializers/ScalarNodeDeserializer.cs           | 3 ++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/YamlDotNet.Test/Serialization/SerializationTests.cs b/YamlDotNet.Test/Serialization/SerializationTests.cs
index 2851dfa2d..eea6138fb 100644
--- a/YamlDotNet.Test/Serialization/SerializationTests.cs
+++ b/YamlDotNet.Test/Serialization/SerializationTests.cs
@@ -137,6 +137,14 @@ public void DeserializeScalarOctalNumber()
             result.Should().Be(29418);
         }
 
+        [Fact]
+        public void DeserializeNullableScalarOctalNumber()
+        {
+            var result = Deserializer.Deserialize<int?>(UsingReaderFor("+071_352"));
+
+            result.Should().Be(29418);
+        }
+
         [Fact]
         public void DeserializeScalarHexNumber()
         {
diff --git a/YamlDotNet/Serialization/NodeDeserializers/ScalarNodeDeserializer.cs b/YamlDotNet/Serialization/NodeDeserializers/ScalarNodeDeserializer.cs
index 62c9acf65..9bcb584df 100644
--- a/YamlDotNet/Serialization/NodeDeserializers/ScalarNodeDeserializer.cs
+++ b/YamlDotNet/Serialization/NodeDeserializers/ScalarNodeDeserializer.cs
@@ -48,7 +48,8 @@ bool INodeDeserializer.Deserialize(IParser parser, Type expectedType, Func<IPars
             }
             else
             {
-                var typeCode = expectedType.GetTypeCode();
+                var underlyingType = Nullable.GetUnderlyingType(expectedType);
+                var typeCode = underlyingType != null ? underlyingType.GetTypeCode() : expectedType.GetTypeCode();
                 switch (typeCode)
                 {
                     case TypeCode.Boolean: