Another attempt to fix the SDK insertion issue related to runtime/apphost downloads (#77845)

Use the EnableRuntimePackDownload/EnableAppHostPackDownload flags to indicate whether the restore should download those packages./

Author: ToddGrun

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj

@@ -44,6 +44,19 @@
     <PublishDir Condition="'$(RuntimeIdentifier)' != ''">$(ArtifactsDir)/LanguageServer/$(Configuration)/$(TargetFramework)/$(RuntimeIdentifier)</PublishDir>
     <PublishDir Condition="'$(RuntimeIdentifier)' == ''">$(ArtifactsDir)/LanguageServer/$(Configuration)/$(TargetFramework)/neutral</PublishDir>
 
+    <!-- List of runtime identifiers that we want to publish an executable for. -->
+    <!-- When building a VMR vertical, we don't need to pack everything. Just pack the passed in TargetRid or BaseOS.
+         TargetRid and BaseOS are provided to roslyn via the build arguments passed in the VMR orchestrator's repo project.
+         https://github.com/dotnet/dotnet/blob/main/repo-projects/roslyn.proj. For definitions of the TargetRid
+         and other common properties, see https://github.com/dotnet/arcade/blob/main/Documentation/UnifiedBuild/Unified-Build-Controls.md -->
+    <RuntimeIdentifiers Condition="'$(TargetRid)' != ''">$(TargetRid)</RuntimeIdentifiers>
+    <RuntimeIdentifiers Condition="'$(BaseOS)' != ''">$(BaseOS)</RuntimeIdentifiers>
+    <RuntimeIdentifiers Condition="'$(TargetRid)' == '' and '$(BaseOS)' == ''">win-x64;win-arm64;linux-x64;linux-arm64;linux-musl-x64;linux-musl-arm64;osx-x64;osx-arm64</RuntimeIdentifiers>
+
+    <!-- These indicate that the runtime/apphost packages should not be downloaded as part of build/restore -->
+    <EnableRuntimePackDownload>false</EnableRuntimePackDownload>
+    <EnableAppHostPackDownload>false</EnableAppHostPackDownload>
+
     <!-- Publish ready to run executables when we're publishing platform specific executables. -->
     <PublishReadyToRun Condition="'$(RuntimeIdentifier)' != '' AND '$(Configuration)' == 'Release' ">true</PublishReadyToRun>
 

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/PackAllRids.targets

@@ -4,25 +4,6 @@
     <ImportNuGetBuildTasksPackTargetsFromSdk>false</ImportNuGetBuildTasksPackTargetsFromSdk>
     <_RoslynPublishReadyToRun>false</_RoslynPublishReadyToRun>
     <_RoslynPublishReadyToRun Condition="'$(Configuration)' == 'Release'">true</_RoslynPublishReadyToRun>
-
-    <!-- 
-      List of runtime identifiers that we want to publish an executable for.
-      This cannot be set in the base project as it will cause issues when roslyn is built
-      as a test project for SDK insertions.  The RuntimeIdentifiers property will cause the build to
-      attempt to download unpublished packages, which fails (until the packages eventually get published).
-
-      The test doesn't actually run pack, so we can instead skip setting the RuntimeIdentifiers property unless
-      we're actually trying to build packages.
-    -->
-    <!-- 
-      When building a VMR vertical, we don't need to pack everything. Just pack the passed in TargetRid or BaseOS.
-      TargetRid and BaseOS are provided to roslyn via the build arguments passed in the VMR orchestrator's repo project.
-      https://github.com/dotnet/dotnet/blob/main/repo-projects/roslyn.proj. For definitions of the TargetRid
-      and other common properties, see https://github.com/dotnet/arcade/blob/main/Documentation/UnifiedBuild/Unified-Build-Controls.md 
-    -->
-    <RuntimeIdentifiers Condition="'$(TargetRid)' != ''">$(TargetRid)</RuntimeIdentifiers>
-    <RuntimeIdentifiers Condition="'$(BaseOS)' != ''">$(BaseOS)</RuntimeIdentifiers>
-    <RuntimeIdentifiers Condition="'$(TargetRid)' == '' and '$(BaseOS)' == ''">win-x64;win-arm64;linux-x64;linux-arm64;linux-musl-x64;linux-musl-arm64;osx-x64;osx-arm64</RuntimeIdentifiers>
   </PropertyGroup>
 
   <Target Name="Pack">
@@ -43,10 +24,13 @@
 
       We also pass the RestoreUseStaticGraphEvaluation=false flag to workaround a long path issue when calling the restore target.
       See https://github.com/NuGet/Home/issues/11968
+
+      We also pass the EnableRuntimePackDownload/EnableAppHostPackDownload flags to indicate we wish for this restore/pack to download
+      the required runtime/apphost packages as those will be needed during the pack.
     -->
-    <MSBuild Projects="$(MSBuildProjectFullPath)" Targets="Restore" Properties="PublishReadyToRun=$(_RoslynPublishReadyToRun);RestoreUseStaticGraphEvaluation=false" />
+    <MSBuild Projects="$(MSBuildProjectFullPath)" Targets="Restore" Properties="EnableRuntimePackDownload=true;EnableAppHostPackDownload=true;PublishReadyToRun=$(_RoslynPublishReadyToRun);RestoreUseStaticGraphEvaluation=false" />
 
-    <MSBuild Projects="@(ProjectToPublish)" Targets="Pack" BuildInParallel="true" />
+    <MSBuild Projects="@(ProjectToPublish)" Targets="Pack" Properties="EnableRuntimePackDownload=true;EnableAppHostPackDownload=true" BuildInParallel="true" />
   </Target>
 
   <!--