Convert language server project into .NET tool by dibarbet · Pull Request #82154 · dotnet/roslyn

dibarbet · 2026-01-26T20:23:19Z

Enable the language server to be published and consumed as a .NET tool. This simplifies publishing (removing custom targets) and simplifies consumption as a plugin

Both the tool package name and command used to invoke it will be roslyn-language-server
e.g.
dotnet tool install roslyn-language-server
dotnet tool run roslyn-language-server

CyrusNajmabadi · 2026-01-26T20:28:29Z

Love the simplification. Could you put something in the PR stating why this is being done?

CyrusNajmabadi · 2026-01-26T21:00:57Z

a simple dotnet tool install command

Nice! what would be put in the <tool> part in this case?

dibarbet · 2026-01-26T21:03:57Z

Nice! what would be put in the <tool> part in this case?

Currently under bikeshedding 😆

Tentatively thinking roslyn-ls but we're open to other ideas. In this PR right now its Microsoft.CodeAnalysis.LanguageServer

...ageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj

dibarbet · 2026-01-27T01:54:49Z

...ageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj

+    Verify that the SymbolPublishingExclusionsFile.txt contains the required entries for the native SQLite library.
+    These don't have symbols we need to publish and they cause symbol check to fail.
+  -->
+  <Target Name="ValidateSymbolPublishingExclusions"


SymbolPublishingExclusionsFile excludes a couple of binaries that we don't own from symbol publishing (they cause symbol check to fail with cryptic errors). Exclusion is based on the path in the nuget package.

Previously that path was quite static, but .NET tool packaging includes the tfm in that path. This target ensures the path in SymbolPublishingExclusionsFile matches the TFM, with a nice error message.

dibarbet · 2026-01-27T01:55:34Z

@jasonmalinowski this has changed a bit, so probably should get a re-review

dibarbet · 2026-01-27T19:51:43Z

...ageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj

+    <IsPackable>true</IsPackable>
+    <PackAsTool>true</PackAsTool>
+    <PackageId>roslyn-language-server</PackageId>
+    <ToolCommandName>roslyn-language-server</ToolCommandName>


The user visible nuget package and tool command will both be roslyn-language-server.

The project name here and the actual executable will still be Microsoft.CodeAnalysis.LanguageServer - I did not rename those as

Generally they aren't user visible (other than the process name)

Its a more complicated with outside impacts (e.g. telemetry).

Thanks. roslyn-language-server makes sense to me :)

eng/config/PublishData.json

...ageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj

dotnet/roslyn#82154

@ViktorHofer

#82387) Mono runtime does not support ReadyToRun compilation. VMR builds with Mono were failing with `NETSDK1094: Unable to optimize assemblies for performance` because `PublishReadyToRun` was unconditionally enabled for Release builds. ## Changes - Add `DotNetBuildUseMonoRuntime` check to `PublishReadyToRun` condition in LanguageServer project - R2R remains enabled for Release builds with standard runtimes - R2R is now disabled when building with Mono runtime ```xml  <PublishReadyToRun Condition="'$(Configuration)' == 'Release' ">true</PublishReadyToRun>  <PublishReadyToRun Condition="'$(Configuration)' == 'Release' AND '$(DotNetBuildUseMonoRuntime)' != 'true' ">true</PublishReadyToRun> ``` > [!WARNING] > > <details> > <summary>Firewall rules blocked me from connecting to one or more addresses (expand for details)</summary> > > #### I tried to connect to the following addresses, but was blocked by firewall rules: > > - `bcnvsblobprodcus378.vsblob.vsassets.io` > - Triggering command: `/usr/share/dotnet/dotnet /usr/share/dotnet/dotnet /usr/share/dotnet/sdk/10.0.102/NuGet.Build.Tasks.Console.dll Recursive=True;CleanupAssetsForUnsupportedProjects=True;DisableParallel=False;Force=False;ForceEvaluate=False;HideWarningsAndErrors=False;IgnoreFailedSources=False;Interactive=False;NoCache=False;NoHttpCache=False;RestorePackagesConfig=False /usr/share/dotnet/sdk/10.0.102/MSBuild.dll /home/REDACTED/work/roslyn/roslyn/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj Configuration=Release;NuGetInteractive=false;EnableDefaultCompileItems=false;EnableDefaultEmbeddedResourceItems=false;EnableDefaultNoneItems=false;MSBuildRestoreSessionId=7ffb2b8c-a068-4049-94e1-0a9559ccf395;MSBuildIsRestoring=True;ExcludeRestorePackageIm` (dns block) > - `vb4vsblobprodcus33.vsblob.vsassets.io` > - Triggering command: `/usr/share/dotnet/dotnet dotnet build src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj -c Release` (dns block) > > If you need me to access, download, or install something from one of these locations, you can either: > > - Configure [Actions setup steps](https://gh.io/copilot/actions-setup-steps) to set up my environment, which run before the firewall is enabled > - Add the appropriate URLs or hosts to the custom allowlist in this repository's [Copilot coding agent settings](https://github.com/dotnet/roslyn/settings/copilot/coding_agent) (admins only) > > </details>  <details> <summary>Original prompt</summary> > > ---- > > *This section details on the original issue you should resolve* > > <issue_title>Mono builds fail due to missing R2R while compiling Roslyn</issue_title> > <issue_description>Mono builds don't do R2R. The vmr builds started failing because Roslyn tries to find a pack for doing R2R: > > ``` > /home/tester/workdir/dotnet/sdk/sdk/11.0.100-preview.2.26081.104/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.FrameworkReferenceResolution.targets(122,5): error NETSDK1094: Unable to optimize assemblies for performance: a valid runtime package was not found. Either set the PublishReadyToRun property to false, or use a supported runtime identifier when publishing. When targeting .NET 6 or higher, make sure to restore packages with the PublishReadyToRun property set to true. [/home/tester/workdir/dotnet/src/roslyn/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj] > ``` > The regression probably happened in #82154 where `PublishReadyToRun` changed from: > ``` > <PublishReadyToRun Condition="'$(RuntimeIdentifier)' != '' AND '$(Configuration)' == 'Release' ">true</PublishReadyToRun> > ``` > to > ``` > <PublishReadyToRun Condition="'$(Configuration)' == 'Release' ">true</PublishReadyToRun> > ``` > > cc @ViktorHofer @dibarbet @omajid </issue_description> > > <agent_instructions>please fix this by checking DotNetBuildUseMonoRuntime before r2r publishing in the roslyn language server</agent_instructions> > > ## Comments on the Issue (you are @copilot in this section) > > <comments> > <comment_new><author>@dibarbet</author><body> > > can we change back to include the `'$(RuntimeIdentifier)' != ''`? > > If I recall correctly, no, with the runtimeidentifier check publishing as a tool did not correctly run R2R. > > > If not, we need to handle the Mono case specially (using DotNetBuildUseMonoRuntime)? > > @tmds to confirm, you mean in the condition check to make sure `DotNetBuildUseMonoRuntime` is not true before setting `PublishReadyToRun`? > </body></comment_new> > </comments> > </details>  - Fixes #82385  --- ✨ Let Copilot coding agent [set things up for you](https://github.com/dotnet/roslyn/issues/new?title=✨+Set+up+Copilot+instructions&body=Configure%20instructions%20for%20this%20repository%20as%20documented%20in%20%5BBest%20practices%20for%20Copilot%20coding%20agent%20in%20your%20repository%5D%28https://gh.io/copilot-coding-agent-tips%29%2E%0A%0A%3COnboard%20this%20repo%3E&assignees=copilot) — coding agent works faster and does higher quality work when set up for your repo.

Convert language server project into .NET tool

0a42508

dibarbet requested a review from a team as a code owner January 26, 2026 20:23

github-actions bot added the Area-Infrastructure label Jan 26, 2026

CyrusNajmabadi approved these changes Jan 26, 2026

View reviewed changes

davidwengier approved these changes Jan 26, 2026

View reviewed changes

jasonmalinowski mentioned this pull request Jan 26, 2026

Overbuilding in roslyn - Microsoft.CodeAnalysis.Workspaces.MSBuild.BuildHost dotnet/dotnet#4416

Closed

jasonmalinowski approved these changes Jan 26, 2026

View reviewed changes

...ageServer/Microsoft.CodeAnalysis.LanguageServer/Microsoft.CodeAnalysis.LanguageServer.csproj Outdated Show resolved Hide resolved

Update package and tool name to roslyn-ls

3874450

dibarbet requested a review from a team as a code owner January 27, 2026 01:50

dibarbet commented Jan 27, 2026

View reviewed changes

build-analysis bot mentioned this pull request Jan 27, 2026

Sometimes the helix SDK uses GetWorkItemsAsync when workitems aren't done processing. dotnet/dnceng#6011

Open

3 tasks

Change to roslyn-language-server

e8e2143

dibarbet commented Jan 27, 2026

View reviewed changes

JoeRobich approved these changes Jan 27, 2026

View reviewed changes

jasonmalinowski approved these changes Jan 27, 2026

View reviewed changes

dibarbet merged commit 73d940f into dotnet:main Jan 28, 2026
28 checks passed

dibarbet deleted the tool branch January 28, 2026 00:01

dotnet-policy-service bot added this to the Next milestone Jan 28, 2026

This was referenced Jan 28, 2026

[release/11.0.1xx-preview1] Source code updates from dotnet/roslyn dotnet/dotnet#4463

Closed

[release/10.0.3xx] Source code updates from dotnet/roslyn dotnet/dotnet#4462

Merged

[main] Source code updates from dotnet/roslyn dotnet/dotnet#4505

Merged

dotnet-bot mentioned this pull request Feb 1, 2026

[Automated] PRs inserted in VS build main-11431.33 #82246

Closed

mmitche added a commit to mmitche/dotnet that referenced this pull request Feb 2, 2026

Update symbol publising exclusions

801f83a

dotnet/roslyn#82154

mmitche mentioned this pull request Feb 2, 2026

[release/10.0.3xx] Update symbol publising exclusions dotnet/dotnet#4602

Merged

github-actions bot pushed a commit to dotnet/dotnet that referenced this pull request Feb 3, 2026

Update symbol publising exclusions dotnet/roslyn#82154

0a19a31

tmds mentioned this pull request Feb 12, 2026

Mono builds fail due to missing R2R while compiling Roslyn #82385

Closed

Copilot AI mentioned this pull request Feb 12, 2026

Fix Mono builds by disabling R2R when DotNetBuildUseMonoRuntime is set #82387

Merged

dotnet-bot mentioned this pull request Feb 18, 2026

[Automated] PRs inserted in VS build feature.debugger.wix5-11517.161 #82436

Closed

akhera99 modified the milestones: Next, 18.5 Feb 24, 2026

dibarbet mentioned this pull request Mar 16, 2026

Add documentation for roslyn-language-server Copilot plugin #82797

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Convert language server project into .NET tool#82154

Convert language server project into .NET tool#82154
dibarbet merged 3 commits intodotnet:mainfrom
dibarbet:tool

dibarbet commented Jan 26, 2026 •

edited

Loading

Uh oh!

CyrusNajmabadi commented Jan 26, 2026

Uh oh!

CyrusNajmabadi commented Jan 26, 2026

Uh oh!

dibarbet commented Jan 26, 2026

Uh oh!

Uh oh!

dibarbet Jan 27, 2026

Uh oh!

dibarbet commented Jan 27, 2026

Uh oh!

dibarbet Jan 27, 2026 •

edited

Loading

Uh oh!

CyrusNajmabadi Jan 27, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

6 participants

Conversation

dibarbet commented Jan 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

CyrusNajmabadi commented Jan 26, 2026

Uh oh!

CyrusNajmabadi commented Jan 26, 2026

Uh oh!

dibarbet commented Jan 26, 2026

Uh oh!

Uh oh!

dibarbet Jan 27, 2026

Choose a reason for hiding this comment

Uh oh!

dibarbet commented Jan 27, 2026

Uh oh!

dibarbet Jan 27, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

CyrusNajmabadi Jan 27, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

6 participants

dibarbet commented Jan 26, 2026 •

edited

Loading

dibarbet Jan 27, 2026 •

edited

Loading