Fix up NativeAoT tests for OpenApi

Author: captainsafia

eng/testing/linker/project.csproj.template

@@ -12,6 +12,10 @@
     <NETCoreAppMaximumVersion>99.9</NETCoreAppMaximumVersion>
     <_ExtraTrimmerArgs>{ExtraTrimmerArgs} $(_ExtraTrimmerArgs)</_ExtraTrimmerArgs>
     <InterceptorsPreviewNamespaces>$(InterceptorsPreviewNamespaces);{InterceptorsPreviewNamespacesArgs}</InterceptorsPreviewNamespaces>
+    <!-- Ensure individual warnings are shown when publishing -->
+    <TrimmerSingleWarn>false</TrimmerSingleWarn>
+    <!-- But ignore the single warn files marked below to suppress their known warnings. -->
+    <NoWarn>$(NoWarn);IL2104</NoWarn>
     {AdditionalProperties}
   </PropertyGroup>
 
@@ -23,4 +27,13 @@
     {AdditionalProjectReferences}
   </ItemGroup>
 
+  <Target Name="ConfigureTrimming"
+          BeforeTargets="PrepareForILLink">
+    <!-- Single warn the following assemblies, which have known warnings, so the warnings can be suppressed for now. -->
+    <ItemGroup>
+      <!-- Remove once https://github.com/microsoft/OpenAPI.NET/pull/1717 is merged. -->
+      <IlcArg Include="--singlewarnassembly:Microsoft.OpenApi" />
+    </ItemGroup>
+  </Target>
+
 </Project>

src/OpenApi/test/Microsoft.AspNetCore.OpenApi.NativeAotTests/Microsoft.AspNetCore.OpenApi.NativeAotTests.proj

@@ -1,13 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <ItemGroup>
-    <!-- Disable tests in production until https://github.com/microsoft/OpenAPI.NET/pull/1717 is merged and
-    released in Microsoft.OpenApi -->
-    <_TestConsoleAppSourceFiles Include="BasicMinimalApiWithOpenApiDependency.cs">
+    <TestConsoleAppSourceFiles Include="BasicMinimalApiWithOpenApiDependency.cs">
       <EnabledProperties>EnableRequestDelegateGenerator</EnabledProperties>
       <InterceptorNamespaces>Microsoft.AspNetCore.Http.Generated</InterceptorNamespaces>
       <DisabledFeatureSwitches>Microsoft.AspNetCore.Mvc.ApiExplorer.IsEnhancedModelMetadataSupported</DisabledFeatureSwitches>
-    </_TestConsoleAppSourceFiles>
+    </TestConsoleAppSourceFiles>
   </ItemGroup>
 
 </Project>