From e48f1c6d342084177f35783b448207ec9b7787f2 Mon Sep 17 00:00:00 2001
From: Dominique Schuppli <stakx@eml.cc>
Date: Thu, 12 May 2022 13:45:43 +0200
Subject: [PATCH 1/3] `NullReferenceException` when setting up task `.Result`
 to return `null`

---
 .../Regressions/IssueReportsFixture.cs        | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tests/Moq.Tests/Regressions/IssueReportsFixture.cs b/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
index 428615aef..c4dc04dd2 100644
--- a/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
+++ b/tests/Moq.Tests/Regressions/IssueReportsFixture.cs
@@ -3802,6 +3802,29 @@ public void No_ArgumentException_due_to_parameter_refness()
 
 		#endregion
 
+		#region 1253
+
+		public class Issue1253
+		{
+			public interface IFoo
+			{
+				Task<string> Bar();
+			}
+
+			[Fact]
+			public async Task Test()
+			{
+				var mock = new Mock<IFoo>();
+				mock.Setup(x => x.Bar().Result).Returns((string)null);
+
+				var result = await mock.Object.Bar();
+
+				Assert.Null(result);
+			}
+		}
+
+		#endregion
+
 		// Old @ Google Code
 
 		#region #47

From ac4b6897e659df5cd7fd9ea60a0c75f796043d2b Mon Sep 17 00:00:00 2001
From: Dominique Schuppli <stakx@eml.cc>
Date: Thu, 12 May 2022 13:46:22 +0200
Subject: [PATCH 2/3] `null` is a valid `.Result` value, don't exclude it

---
 src/Moq/Invocation.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Moq/Invocation.cs b/src/Moq/Invocation.cs
index b859d11f0..d6d52422e 100644
--- a/src/Moq/Invocation.cs
+++ b/src/Moq/Invocation.cs
@@ -97,7 +97,7 @@ public void ConvertResultToAwaitable(IAwaitableFactory awaitableFactory)
 			{
 				this.result = awaitableFactory.CreateFaulted(r.Exception);
 			}
-			else if (this.result != null && !this.method.ReturnType.IsAssignableFrom(this.result.GetType()))
+			else if (!this.method.ReturnType.IsAssignableFrom(this.result?.GetType()))
 			{
 				this.result = awaitableFactory.CreateCompleted(this.result);
 			}

From 2cfc109f98d13e7736c0865c43614148afd344a3 Mon Sep 17 00:00:00 2001
From: Dominique Schuppli <stakx@eml.cc>
Date: Thu, 12 May 2022 13:47:37 +0200
Subject: [PATCH 3/3] Update changelog

---
 CHANGELOG.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1db6d256c..9be8f1824 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,13 @@ All notable changes to this project will be documented in this file.
 The format is loosely based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 
+## Unreleased
+
+#### Fixed
+
+* Difference in behavior when mocking async method using `.Result` vs without (@cyungmann, #1253)
+
+
 ## 4.18.0 (2022-05-12)
 
 New major version of DynamicProxy (you may get better performance!), so please update with care.