From 0a8d27b2071d0773a52b17b862da6e6d042ed9ac Mon Sep 17 00:00:00 2001
From: Eric Erhardt <eric.erhardt@microsoft.com>
Date: Thu, 4 Feb 2021 13:21:43 -0600
Subject: [PATCH 1/2] Add nullablePublicOnly Roslyn Feature

This tells Roslyn to not add [AllowNull] attributes in IL to non-public APIs. The same feature is set for dotnet/runtime.
---
 eng/targets/CSharp.Common.props | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/eng/targets/CSharp.Common.props b/eng/targets/CSharp.Common.props
index bddce450d74d..75bbfcc7743c 100644
--- a/eng/targets/CSharp.Common.props
+++ b/eng/targets/CSharp.Common.props
@@ -4,7 +4,7 @@
     <LangVersion>9.0</LangVersion>
 
     <!-- Enables Strict mode for Roslyn compiler -->
-    <Features>strict</Features>
+    <Features>strict;nullablePublicOnly</Features>
   </PropertyGroup>
 
   <ItemGroup>

From 28c70138b2573e84a626eeee684f9f49cd09b527 Mon Sep 17 00:00:00 2001
From: Eric Erhardt <eric.erhardt@microsoft.com>
Date: Fri, 5 Feb 2021 10:20:23 -0600
Subject: [PATCH 2/2] Fix tests that rely on nullability to be preserved on
 non-public types.

---
 .../test/Microsoft.AspNetCore.Mvc.DataAnnotations.Test.csproj   | 2 ++
 .../Microsoft.AspNetCore.Mvc.IntegrationTests.csproj            | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/src/Mvc/Mvc.DataAnnotations/test/Microsoft.AspNetCore.Mvc.DataAnnotations.Test.csproj b/src/Mvc/Mvc.DataAnnotations/test/Microsoft.AspNetCore.Mvc.DataAnnotations.Test.csproj
index 1372cf33ea00..b77a56dc7b43 100644
--- a/src/Mvc/Mvc.DataAnnotations/test/Microsoft.AspNetCore.Mvc.DataAnnotations.Test.csproj
+++ b/src/Mvc/Mvc.DataAnnotations/test/Microsoft.AspNetCore.Mvc.DataAnnotations.Test.csproj
@@ -3,6 +3,8 @@
   <PropertyGroup>
     <TargetFramework>$(DefaultNetCoreTargetFramework)</TargetFramework>
     <UseSharedCompilation>false</UseSharedCompilation>
+    <!-- This project has tests that rely on nullability on non-public types. Undo nullablePublicOnly configured by default -->
+    <Features>$(Features.Replace('nullablePublicOnly', ''))</Features>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/Mvc/test/Mvc.IntegrationTests/Microsoft.AspNetCore.Mvc.IntegrationTests.csproj b/src/Mvc/test/Mvc.IntegrationTests/Microsoft.AspNetCore.Mvc.IntegrationTests.csproj
index 219c48691150..2645610a14bb 100644
--- a/src/Mvc/test/Mvc.IntegrationTests/Microsoft.AspNetCore.Mvc.IntegrationTests.csproj
+++ b/src/Mvc/test/Mvc.IntegrationTests/Microsoft.AspNetCore.Mvc.IntegrationTests.csproj
@@ -3,6 +3,8 @@
   <PropertyGroup>
     <TargetFramework>$(DefaultNetCoreTargetFramework)</TargetFramework>
     <UseSharedCompilation>false</UseSharedCompilation>
+    <!-- This project has tests that rely on nullability on non-public types. Undo nullablePublicOnly configured by default -->
+    <Features>$(Features.Replace('nullablePublicOnly', ''))</Features>
   </PropertyGroup>
 
   <ItemGroup>