Add Oxpecker repository to build check

UseLocalCompiler.Directory.Build.props

@@ -39,7 +39,28 @@
     <FSharpOverridesTargetsShim>$(LocalFSharpBuildBinPath)/Microsoft.FSharp.Overrides.NetSdk.targets</FSharpOverridesTargetsShim>
   </PropertyGroup>
 
-  <ItemGroup>
-    <Reference Include="$(LocalFSharpCompilerPath)/artifacts/bin/FSharp.Core/$(LocalFSharpCompilerConfiguration)/netstandard2.0/FSharp.Core.dll" />
-  </ItemGroup>
+  <!--
+    Reference the locally built FSharp.Core, picking the assembly that matches how NuGet would
+    resolve the FSharp.Core package for the consuming project's target framework:
+      - .NET Framework and netstandard2.0 consumers get the netstandard2.0 assembly.
+      - Everything else (.NET Core / .NET 5+, netstandard2.1) gets the netstandard2.1 assembly,
+        which exposes the IAsyncDisposable-based members (e.g. the task builder 'Using' overload).
+    This runs in a target (rather than a plain ItemGroup) because TargetFramework is not yet known
+    while Directory.Build.props is being evaluated. It runs before ResolvePackageAssets so the
+    reference participates in package conflict resolution and suppresses any older FSharp.Core
+    pulled in transitively by third-party packages.
+  -->
+  <Target Name="AddLocalFSharpCoreReference"
+          Condition="'$(LocalFSharpCompilerPath)' != ''"
+          BeforeTargets="ResolvePackageAssets;ResolveAssemblyReferences;CollectPackageReferences;CoreCompile">
+    <PropertyGroup>
+      <_LocalFSharpCoreTfm Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'">netstandard2.0</_LocalFSharpCoreTfm>
+      <_LocalFSharpCoreTfm Condition="'$(_LocalFSharpCoreTfm)' == '' and $(TargetFramework.StartsWith('net4'))">netstandard2.0</_LocalFSharpCoreTfm>
+      <_LocalFSharpCoreTfm Condition="'$(_LocalFSharpCoreTfm)' == '' and '$(TargetFramework)' == 'netstandard2.0'">netstandard2.0</_LocalFSharpCoreTfm>
+      <_LocalFSharpCoreTfm Condition="'$(_LocalFSharpCoreTfm)' == ''">netstandard2.1</_LocalFSharpCoreTfm>
+    </PropertyGroup>
+    <ItemGroup>
+      <Reference Include="$(LocalFSharpCompilerPath)/artifacts/bin/FSharp.Core/$(LocalFSharpCompilerConfiguration)/$(_LocalFSharpCoreTfm)/FSharp.Core.dll" />
+    </ItemGroup>
+  </Target>
 </Project>

azure-pipelines-PR.yml

@@ -562,6 +562,11 @@ stages:
           - script: .\Build.cmd -c Release -pack
             env:
               NativeToolsOnMachine: true
+              # This step runs Build.cmd without -ci, so Arcade treats it as a local build and
+              # re-enables UpdateXlfOnBuild. That intermittently fails on the multi-targeted
+              # FSharp.Core build with 'The target "UpdateXlf" does not exist ... [TargetFramework=netstandard2.1]'
+              # (dotnet/fsharp#19961). Updating xlf files is never needed in CI, so disable it here.
+              UpdateXlfOnBuild: 'false'
           - script: .\tests\EndToEndBuildTests\EndToEndBuildTests.cmd -c Release
             displayName: End to end build tests
 
@@ -818,6 +823,14 @@ stages:
           commit: e81e00a464b9d35d272f61708a1a0bfbf487b6d5
           buildScript: dotnet build Nu.sln --configuration Release
           displayName: Nu_Build
+        - repo: Lanayx/Oxpecker
+          commit: cb7e4b83e3f2aba7ded46b17a36d1aea8c13c292
+          buildScript: dotnet build .\Oxpecker.slnx -bl
+          displayName: Oxpecker_Build
+        - repo: Lanayx/Oxpecker
+          commit: cb7e4b83e3f2aba7ded46b17a36d1aea8c13c292
+          buildScript: dotnet build .\Oxpecker.Solid.slnx -bl
+          displayName: Oxpecker_Solid_Build
         # Design-time provider packaging oracle. Pin d8aba70 (pre-workaround base of FSharp.Data.GraphQL#583):
         # it uses the bare IsFSharpDesignTimeProvider gesture, so the client pack drops the provider without this fix.
         # Linux-only: the $PWD local feed and the grep content assertion need bash. (nupkg entry names are stored

src/Microsoft.CommonLanguageServerProtocol.Framework.Proxy/Microsoft.CommonLanguageServerProtocol.Framework.Proxy.csproj

@@ -9,6 +9,8 @@
 	<ItemGroup>
 		<PackageReference Include="Microsoft.CommonLanguageServerProtocol.Framework" PrivateAssets="all" Version="4.13.0-3.24579.1" />
 		<PackageReference Include="Microsoft.VisualStudio.Threading" Version="17.12.21" />
+		<!-- Pin the transitive MessagePack (via StreamJsonRpc) to a patched version. Older versions (< 2.5.301) have known vulnerabilities (NU1902/NU1903). -->
+		<PackageReference Include="MessagePack" Version="2.5.302" />
 	</ItemGroup>
 
 	<ItemGroup>

tests/FSharp.Compiler.Service.Tests/ErrorList/ScriptDiagnosticsTests.fs

@@ -1,4 +1,9 @@
-[<FSharp.Test.RunTestCasesInSequence>]
+// Serialized (NotThreadSafeResourceCollection => DisableParallelization) because the #r/#load
+// script tests resolve references through the shared checker and process-global reference
+// resolver. Running concurrently with other collections intermittently drops closure
+// diagnostics (e.g. a missing '#r' surfacing as 0 diagnostics). RunTestCasesInSequence alone
+// is a no-op marker and does not prevent cross-collection parallelism.
+[<Xunit.Collection(nameof FSharp.Test.NotThreadSafeResourceCollection)>]
 module FSharp.Compiler.Service.Tests.ScriptDiagnosticsTests
 
 open System