dotnet · eiriktsarpalis · Dec 16, 2022 · Dec 13, 2022 · Dec 13, 2022 · Dec 13, 2022
diff --git a/Directory.Build.props b/Directory.Build.props
@@ -349,6 +349,7 @@
                                 '$(IsPublishedAppTestProject)' != 'true' and
                                 '$(IsTestSupportProject)' != 'true' and
                                 '$(UsingMicrosoftDotNetSharedFrameworkSdk)' != 'true' and
+                                '$(MSBuildProjectExtension)' != '.pkgproj' and
                                 '$(UsingMicrosoftNoTargetsSdk)' != 'true' and
                                 '$(UsingMicrosoftTraversalSdk)' != 'true'">true</IsSourceProject>
   </PropertyGroup>

diff --git a/Directory.Build.targets b/Directory.Build.targets
@@ -77,7 +77,7 @@
     <!-- Keep in sync as required by the Packaging SDK in Arcade. -->
     <Description>$(PackageDescription)</Description>
   </PropertyGroup>
-  
+
   <ItemDefinitionGroup>
     <TargetPathWithTargetPlatformMoniker>
       <IsReferenceAssemblyProject>$(IsReferenceAssemblyProject)</IsReferenceAssemblyProject>
@@ -118,14 +118,15 @@
       <_analyzerPath Condition="'$(AnalyzerLanguage)' != ''">$(_analyzerPath)/$(AnalyzerLanguage)</_analyzerPath>
     </PropertyGroup>
 
+    <!-- Filter on netstandard2.0 so that generator projects can multi-target for the purpose of enabling nullable reference type compiler checks. -->
     <ItemGroup>
-      <_AnalyzerPackFile Include="@(_BuildOutputInPackage)" IsSymbol="false" />
-      <_AnalyzerPackFile Include="@(_TargetPathsToSymbols)" IsSymbol="true" />
+      <_AnalyzerPackFile Include="@(_BuildOutputInPackage->WithMetadataValue('TargetFramework', 'netstandard2.0'))" IsSymbol="false" />
+      <_AnalyzerPackFile Include="@(_TargetPathsToSymbols->WithMetadataValue('TargetFramework', 'netstandard2.0'))" IsSymbol="true" />
       <_AnalyzerPackFile PackagePath="$(_analyzerPath)/%(TargetPath)" />
     </ItemGroup>
 
-    <Error Condition="'%(_AnalyzerPackFile.TargetFramework)' != 'netstandard2.0'"
-           Text="Analyzers must only target netstandard2.0 since they run in the compiler which targets netstandard2.0. The following files were found to target '%(_AnalyzerPackFile.TargetFramework)': @(_AnalyzerPackFile)" />
+    <Error Text="Analyzers must target netstandard2.0 since they run in the compiler which targets netstandard2.0. $(MSBuildProjectFullPath) targets '$([MSBuild]::ValueOrDefault('$(TargetFrameworks)', '$(TargetFramework)'))' instead."
+           Condition="'@(_AnalyzerPackFile)' == ''" />
   </Target>
 
   <!-- Allows building against source assemblies when the 'SkipUseReferenceAssembly' attribute is present on ProjectReference items. -->
@@ -161,6 +162,35 @@
     </ItemGroup>
   </Target>
 
+  <!-- Filter out conflicting implicit assembly references. -->
+  <Target Name="FilterImplicitAssemblyReferences"
+          Condition="'$(DisableImplicitFrameworkReferences)' != 'true'"
+          DependsOnTargets="ResolveProjectReferences"
+          AfterTargets="ResolveTargetingPackAssets">
+    <ItemGroup>
+      <_targetingPackReferenceExclusion Include="$(TargetName)" />
+      <_targetingPackReferenceExclusion Include="@(_ResolvedProjectReferencePaths->Metadata('Filename'))" />
+      <_targetingPackReferenceExclusion Include="@(DefaultReferenceExclusion)" />
+    </ItemGroup>
+
+    <!-- Filter out shims from the targeting pack references as an opt-in. -->
+    <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp' and
+                          '$(SkipTargetingPackShimReferences)' == 'true'">
+      <_targetingPackReferenceExclusion Include="@(NetFxReference)" />
+      <_targetingPackReferenceExclusion Include="netstandard" />
+    </ItemGroup>
+
+    <ItemGroup>
+      <_targetingPackReferenceWithProjectName Include="@(Reference->WithMetadataValue('ExternallyResolved', 'true')->Metadata('Filename'))"
+                                              OriginalIdentity="%(Identity)" />
+      <_targetingPackIncludedReferenceWithProjectName Include="@(_targetingPackReferenceWithProjectName)"
+                                                      Exclude="@(_targetingPackReferenceExclusion)" />
+      <_targetingPackExcludedReferenceWithProjectName Include="@(_targetingPackReferenceWithProjectName)"
+                                                      Exclude="@(_targetingPackIncludedReferenceWithProjectName)" />
+      <Reference Remove="@(_targetingPackExcludedReferenceWithProjectName->Metadata('OriginalIdentity'))" />
+    </ItemGroup>
+  </Target>
+
   <!--
     Arcade SDK versioning is defined by static properties in a targets file: work around this by
     moving properties based on versioning into a target.

diff --git a/docs/coding-guidelines/project-guidelines.md b/docs/coding-guidelines/project-guidelines.md
@@ -190,6 +190,8 @@ All test outputs should be under
 In the gen directory any source generator related to the assembly should exist. This does not mean the source generator is only used for that assembly only that it is conceptually apart of that assembly. For example, the assembly may provide attributes or low-level types the source generator uses.
 To consume a source generator, simply add a `<ProjectReference Include="..." ReferenceOutputAssembly="false" OutputItemType="Analyzer" />` item to the project, usually next to the `Reference` and `ProjectReference` items.
 
+A source generator must target `netstandard2.0` as such assemblies are loaded into the compiler's process which might run on either .NET Framework or modern .NET depending on the tooling being used (CLI vs Visual Studio). While that's true, a source project can still multi-target and include `$(NetCoreAppToolCurrent)` (which is the latest non live-built .NETCoreApp tfm that is supported by the SDK) to benefit from the ehancanced nullable reference type warnings emitted by the compiler. For an example see [System.Text.Json's roslyn4.4 source generator](/src/libraries/System.Text.Json/gen/System.Text.Json.SourceGeneration.Roslyn4.4.csproj). While the repository's infrastructure makes sure that only the source generator's `netstandard2.0` build output is included in packages, to consume such a multi-targeting source generator via a `ProjectReference` (as described above), you need to add the `ReferringTargetFramework=netstandard2.0` metadata to the ProjectReference item to guarantee that the netstandard2.0 asset is chosen.
+
 ## Facades
 Facade are unique in that they don't have any code and instead are generated by finding a contract reference assembly with the matching identity and generating type forwards for all the types to where they live in the implementation assemblies (aka facade seeds). There are also partial facades which contain some type forwards as well as some code definitions. All the various build configurations should be contained in the one csproj file per library.
 

diff --git a/eng/Versions.props b/eng/Versions.props
@@ -55,7 +55,7 @@
       The exact version is a moving target until we ship.
       It should never go ahead of the Roslyn version included in the SDK version in dotnet/arcade's global.json to avoid causing breaks in product construction.
     -->
-    <MicrosoftCodeAnalysisVersion_4_4>4.4.0-2.22423.18</MicrosoftCodeAnalysisVersion_4_4>
+    <MicrosoftCodeAnalysisVersion_4_4>4.4.0</MicrosoftCodeAnalysisVersion_4_4>
     <!-- Compatibility with the latest Visual Studio Preview release -->
     <!--
       The exact version is always a moving target. This version should never go ahead of the version of Roslyn that is included in the most recent
@@ -64,7 +64,7 @@
       When we are building from source, we care more about reducing pre-built requirements than inner-loop dev experience, so we update this to be the same version
       as MicrosoftCodeAnalysisVersion.
     -->
-    <MicrosoftCodeAnalysisVersion_LatestVS>4.4.0-2.22423.18</MicrosoftCodeAnalysisVersion_LatestVS>
+    <MicrosoftCodeAnalysisVersion_LatestVS>4.4.0</MicrosoftCodeAnalysisVersion_LatestVS>
     <MicrosoftCodeAnalysisVersion_LatestVS Condition="'$(DotNetBuildFromSource)' == 'true'">$(MicrosoftCodeAnalysisVersion)</MicrosoftCodeAnalysisVersion_LatestVS>
     <!-- Some of the analyzer dependencies used by ILLink project -->
     <MicrosoftCodeAnalysisCSharpAnalyzerTestingXunitVersion>1.0.1-beta1.21265.1</MicrosoftCodeAnalysisCSharpAnalyzerTestingXunitVersion>

diff --git a/eng/packaging.targets b/eng/packaging.targets
@@ -150,7 +150,8 @@
   <Target Name="IncludeAnalyzersInPackage"
           Condition="'@(ProjectReference)' != '' and @(ProjectReference->AnyHaveMetadataValue('PackAsAnalyzer', 'true'))">
     <MSBuild Projects="@(ProjectReference->WithMetadataValue('PackAsAnalyzer', 'true'))"
-             Targets="GetAnalyzerPackFiles">
+             Targets="GetAnalyzerPackFiles"
+             RemoveProperties="SetTargetFramework">
       <Output TaskParameter="TargetOutputs" ItemName="_AnalyzerFile" />
     </MSBuild>
 

diff --git a/eng/targetingpacks.targets b/eng/targetingpacks.targets
@@ -19,7 +19,7 @@
                             '$(TargetFrameworkIdentifier)' == '.NETCoreApp' and
                             '$(TargetFrameworkVersion)' == 'v$(NetCoreAppCurrentVersion)'">
     <UseLocalTargetingRuntimePack Condition="'$(UseLocalTargetingRuntimePack)' == ''">true</UseLocalTargetingRuntimePack>
-    <UseLocalAppHostPack Condition="'$(UseLocalAppHostPack)' == ''">true</UseLocalAppHostPack>
+    <UseLocalAppHostPack Condition="'$(UseLocalAppHostPack)' == ''">$(UseLocalTargetingRuntimePack)</UseLocalAppHostPack>
     <EnableTargetingPackDownload>false</EnableTargetingPackDownload>
     <!-- TODO: Enable when a 8.0.100 SDK is consumed
     <EnableRuntimePackDownload>false</EnableRuntimePackDownload>
@@ -171,33 +171,4 @@
                         Condition="'%(RuntimeFramework.FrameworkName)' == '$(LocalFrameworkOverrideName)'" />
     </ItemGroup>
   </Target>
-
-  <!-- Filter out conflicting implicit assembly references. -->
-  <Target Name="FilterImplicitAssemblyReferences"
-          Condition="'$(DisableImplicitFrameworkReferences)' != 'true'"
-          DependsOnTargets="ResolveProjectReferences"
-          AfterTargets="ResolveTargetingPackAssets">
-    <ItemGroup>
-      <_targetingPackReferenceExclusion Include="$(TargetName)" />
-      <_targetingPackReferenceExclusion Include="@(_ResolvedProjectReferencePaths->Metadata('Filename'))" />
-      <_targetingPackReferenceExclusion Include="@(DefaultReferenceExclusion)" />
-    </ItemGroup>
-
-    <!-- Filter out shims from the targeting pack references as an opt-in. -->
-    <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp' and
-                          '$(SkipTargetingPackShimReferences)' == 'true'">
-      <_targetingPackReferenceExclusion Include="@(NetFxReference)" />
-      <_targetingPackReferenceExclusion Include="netstandard" />
-    </ItemGroup>
-
-    <ItemGroup>
-      <_targetingPackReferenceWithProjectName Include="@(Reference->WithMetadataValue('ExternallyResolved', 'true')->Metadata('Filename'))"
-                                              OriginalIdentity="%(Identity)" />
-      <_targetingPackIncludedReferenceWithProjectName Include="@(_targetingPackReferenceWithProjectName)"
-                                                      Exclude="@(_targetingPackReferenceExclusion)" />
-      <_targetingPackExcludedReferenceWithProjectName Include="@(_targetingPackReferenceWithProjectName)"
-                                                      Exclude="@(_targetingPackIncludedReferenceWithProjectName)" />
-      <Reference Remove="@(_targetingPackExcludedReferenceWithProjectName->Metadata('OriginalIdentity'))" />
-    </ItemGroup>
-  </Target>
 </Project>
diff --git a/src/libraries/Common/src/Roslyn/SyntaxValueProvider_ForAttributeWithSimpleName.cs b/src/libraries/Common/src/Roslyn/SyntaxValueProvider_ForAttributeWithSimpleName.cs
@@ -36,10 +36,10 @@ public SyntaxTreeInfo(SyntaxTree tree, bool containsGlobalAliases, bool contains
             ContainsAttributeList = containsAttributeList;
         }
 
-        public bool Equals(SyntaxTreeInfo other)
+        public bool Equals(SyntaxTreeInfo? other)
             => Tree == other?.Tree;
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
             => this.Equals(obj as SyntaxTreeInfo);
 
         public override int GetHashCode()

diff --git a/src/libraries/Directory.Build.targets b/src/libraries/Directory.Build.targets
@@ -55,6 +55,8 @@
                                 !$(NetCoreAppLibraryNoReference.Contains('$(AssemblyName);'))">true</IsNETCoreAppRef>
     <IsNETCoreAppAnalyzer Condition="'$(IsGeneratorProject)' == 'true' and
                                      $(NetCoreAppLibraryGenerator.Contains('$(MSBuildProjectName);'))">true</IsNETCoreAppAnalyzer>
+    <!-- Inbox analyzers shouldn't use the live targeting / runtime pack. They better depend on an LKG to avoid layering concerns. -->
+    <UseLocalTargetingRuntimePack Condition="'$(IsNETCoreAppAnalyzer)' == 'true'">false</UseLocalTargetingRuntimePack>
     <!-- By default, disable implicit framework references for NetCoreAppCurrent libraries. -->
     <DisableImplicitFrameworkReferences Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp' and
                                                    $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '$(NETCoreAppCurrentVersion)')) and
@@ -95,8 +97,10 @@
       <RuntimePath>$(LibrariesAllBinArtifactsPath)</RuntimePath>
     </BinPlaceTargetFrameworks>
 
+    <!-- Source generator projects might multi-target. Make sure that only the netstandard2.0 compiled assets get binplaced. -->
     <BinPlaceDir Include="$(MicrosoftNetCoreAppRefPackDir)analyzers\dotnet\$(AnalyzerLanguage)"
-                 Condition="'$(IsNETCoreAppAnalyzer)' == 'true'" />
+                 Condition="'$(IsNETCoreAppAnalyzer)' == 'true' and
+                            '$(TargetFramework)' == 'netstandard2.0'" />
 
     <!-- Setup the shared framework directory for testing -->
     <BinPlaceTargetFrameworks Include="$(NetCoreAppCurrent)-$(TargetOS)">

diff --git a/src/libraries/System.Text.Json/Common/ReflectionExtensions.cs b/src/libraries/System.Text.Json/Common/ReflectionExtensions.cs
@@ -41,9 +41,14 @@ internal static partial class ReflectionExtensions
 
         public static Type? GetCompatibleGenericBaseClass(
             this Type type,
-            Type baseType,
+            Type? baseType,
             bool sourceGenType = false)
         {
+            if (baseType is null)
+            {
+                return null;
+            }
+
             Debug.Assert(baseType.IsGenericType);
             Debug.Assert(!baseType.IsInterface);
             Debug.Assert(baseType == baseType.GetGenericTypeDefinition());

diff --git a/src/libraries/System.Text.Json/System.Text.Json.sln b/src/libraries/System.Text.Json/System.Text.Json.sln
@@ -43,7 +43,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "System.Text.Json", "ref\Sys
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "System.Text.Json", "src\System.Text.Json.csproj", "{1285FF43-F491-4BE0-B92C-37DA689CBD4B}"
 EndProject
-Project("{F2A71F9B-5D33-465A-A702-920D77279786}") = "System.Text.Json.FSharp.Tests", "tests\System.Text.Json.FSharp.Tests\System.Text.Json.FSharp.Tests.fsproj", "{5720BF06-2031-4AD8-B9B4-31A01E27ABB8}"
+Project("{6EC3EE1D-3C4E-46DD-8F32-0CC8E7565705}") = "System.Text.Json.FSharp.Tests", "tests\System.Text.Json.FSharp.Tests\System.Text.Json.FSharp.Tests.fsproj", "{5720BF06-2031-4AD8-B9B4-31A01E27ABB8}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "System.Text.Json.TestLibrary.Roslyn3.11", "tests\System.Text.Json.SourceGeneration.TestLibrary\System.Text.Json.TestLibrary.Roslyn3.11.csproj", "{5C0CE30B-DD4A-4F7A-87C0-5243F0C86885}"
 EndProject
@@ -199,35 +199,35 @@ Global
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 		{102945CA-3736-4B2C-8E68-242A0B247F2B} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{5720BF06-2031-4AD8-B9B4-31A01E27ABB8} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{5C0CE30B-DD4A-4F7A-87C0-5243F0C86885} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{FCA21178-0411-45D6-B597-B7BE145CEE33} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{66AD4B7E-CF15-4A8F-8BF8-7E1BC6176D07} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{33599A6C-F340-4E1B-9B4D-CB8946C22140} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{256A4653-4287-44B3-BDEF-67FC1522ED2F} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{F6A18EB5-A8CC-4A39-9E85-5FA226019C3D} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
-		{A0178BAA-A1AF-4C69-8E4A-A700A2723DDC} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
 		{73D5739C-E382-4E22-A7D3-B82705C58C74} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{E9AA0AEB-AEAE-4B28-8D4D-17A6D7C89D17} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
 		{282400DF-F3D8-4419-90F1-1E2F2D8B760C} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{6E9E4359-44F8-45AA-AEC5-D0F9FFBB13D6} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
 		{09F77672-101E-4495-9D88-29376919C121} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
 		{BE27618A-2916-4269-9AD5-6BC5EDC32B30} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{1C8262DB-7355-40A8-A2EC-4EED7363134A} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
 		{C2C7BA09-F9EE-4E43-8EE4-871CC000342C} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
 		{4774F56D-16A8-4ABB-8C73-5F57609F1773} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{D05FD93A-BC51-466E-BD56-3F3D6BBE6B06} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
 		{B6D364E7-E5DB-4CF4-B87F-3CEDA3FF7478} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{B815304D-502E-402C-ACE1-878DB4985CCC} = {F254F143-4704-4432-9995-20D87FA8BF8D}
+		{E4B72517-C694-486A-950E-6AB03C651FDC} = {F254F143-4704-4432-9995-20D87FA8BF8D}
 		{FAB4FFF2-964D-45FF-89CC-8BB9CE618ED1} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
 		{C56337BB-8CBC-4EE5-AB4D-8BB0A922813E} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
-		{7015E94D-D20D-48C8-86D7-6A996BE99E0E} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
-		{E9AA0AEB-AEAE-4B28-8D4D-17A6D7C89D17} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
-		{6E9E4359-44F8-45AA-AEC5-D0F9FFBB13D6} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
-		{1C8262DB-7355-40A8-A2EC-4EED7363134A} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
-		{D05FD93A-BC51-466E-BD56-3F3D6BBE6B06} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
 		{9BCCDA15-8907-4AE3-8871-2F17775DDE4C} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
-		{1285FF43-F491-4BE0-B92C-37DA689CBD4B} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
-		{B815304D-502E-402C-ACE1-878DB4985CCC} = {F254F143-4704-4432-9995-20D87FA8BF8D}
-		{E4B72517-C694-486A-950E-6AB03C651FDC} = {F254F143-4704-4432-9995-20D87FA8BF8D}
 		{04AEB008-EE4F-44DE-A361-2DBD2D0FD6A4} = {F254F143-4704-4432-9995-20D87FA8BF8D}
 		{6485EED4-C313-4551-9865-8ADCED603629} = {F254F143-4704-4432-9995-20D87FA8BF8D}
 		{143AFE8A-3490-444C-A82D-6A375EB59F01} = {F254F143-4704-4432-9995-20D87FA8BF8D}
+		{7015E94D-D20D-48C8-86D7-6A996BE99E0E} = {0371C5D8-D5F5-4747-9810-D91D71D8C0E4}
+		{1285FF43-F491-4BE0-B92C-37DA689CBD4B} = {E49881A9-09F6-442F-9E1D-6D87F5F837F1}
+		{5720BF06-2031-4AD8-B9B4-31A01E27ABB8} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{5C0CE30B-DD4A-4F7A-87C0-5243F0C86885} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{FCA21178-0411-45D6-B597-B7BE145CEE33} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{66AD4B7E-CF15-4A8F-8BF8-7E1BC6176D07} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{33599A6C-F340-4E1B-9B4D-CB8946C22140} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{256A4653-4287-44B3-BDEF-67FC1522ED2F} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{F6A18EB5-A8CC-4A39-9E85-5FA226019C3D} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
+		{A0178BAA-A1AF-4C69-8E4A-A700A2723DDC} = {E07C6980-EB71-4D19-A80A-7BEB80B635B1}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {5868B757-D821-41FC-952E-2113A0519506}

diff --git a/src/libraries/System.Text.Json/gen/ContextGenerationSpec.cs b/src/libraries/System.Text.Json/gen/ContextGenerationSpec.cs
@@ -16,17 +16,17 @@ namespace System.Text.Json.SourceGeneration
     [DebuggerDisplay("ContextTypeRef={ContextTypeRef}")]
     internal sealed class ContextGenerationSpec
     {
-        public Location Location { get; init; }
+        public required Location Location { get; init; }
 
-        public JsonSourceGenerationOptionsAttribute GenerationOptions { get; init; }
+        public required JsonSourceGenerationOptionsAttribute GenerationOptions { get; init; }
 
-        public Type ContextType { get; init; }
+        public required Type ContextType { get; init; }
 
         public List<TypeGenerationSpec> RootSerializableTypes { get; } = new();
 
-        public HashSet<TypeGenerationSpec>? ImplicitlyRegisteredTypes { get; } = new();
+        public HashSet<TypeGenerationSpec> ImplicitlyRegisteredTypes { get; } = new();
 
-        public List<string> ContextClassDeclarationList { get; init; }
+        public required List<string> ContextClassDeclarationList { get; init; }
 
         /// <summary>
         /// Types that we have initiated serialization metadata generation for. A type may be discoverable in the object graph,