Move bootstrap logic into MSBuild targets

.github/copilot-instructions.md

@@ -27,26 +27,24 @@ Plan your task:
 
 Always run the core command. Always verify exit codes. No assumptions.
 
-## 1. Core Command
+## 1. Build
 ```
-./build.sh -c Release --testcoreclr
+dotnet build FSharp.sln -c Release
 ```
-Non‑zero → classify & stop.
 
-## 2. Bootstrap (Failure Detection Only)
-Two-phase build. No separate bootstrap command.  
-Early proto/tool errors (e.g. "Error building tools") → `BootstrapFailure` (capture key lines). Stop.
+## 2. Test
+```
+dotnet test tests/FSharp.Compiler.ComponentTests -c Release
+dotnet test tests/FSharp.Compiler.Service.Tests -c Release
+```
 
 ## 3. Build Failure
-Proto ok but solution build fails → `BuildFailure`.  
 Capture exit code, ≤15 error lines (`error FS`, `error F#`, `error MSB`), binlog path: `artifacts/log/Release/Build.*.binlog`.  
 Do not proceed to tests.
 
-## 4. Tests
-Core command runs CoreCLR tests:
+## 4. Tests (Full Suite)
+Additional CoreCLR tests:
 - FSharp.Test.Utilities
-- FSharp.Compiler.ComponentTests
-- FSharp.Compiler.Service.Tests
 - FSharp.Compiler.Private.Scripting.UnitTests
 - FSharp.Build.UnitTests
 - FSharp.Core.UnitTests

.github/workflows/copilot-setup-steps.yml

@@ -14,19 +14,12 @@ jobs:
     # You can define any steps you want, and they will run before the agent starts.
     # If you do not check out your code, Copilot will do this for you.
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: actions/checkout@v4
       - uses: actions/setup-dotnet@v4
         with:
           global-json-file: global.json
-      - name: Restore the compiler service solution
-        env:
-          CI: false
-        run: ./build.sh -c Release --verbosity quiet || true
-      - name: Restore the language server solution
-        env:
-          CI: false
-        run: dotnet build ./LSPSolutionSlim.sln -c Release --verbosity quiet || true
-      - name: Restore dotnet tools
-        env:
-          CI: false
-        run: dotnet tool restore
+      - name: Restore
+        run: |
+          dotnet restore FSharp.sln || true
+          dotnet restore LSPSolutionSlim.sln || true
+          dotnet tool restore || true

Directory.Build.targets

@@ -1,4 +1,5 @@
 <Project>
+  <Import Project="eng/targets/Bootstrap.targets" Condition="'$(DISABLE_ARCADE)' != 'true'" />
   <Import Project="FSharpBuild.Directory.Build.targets" Condition = " '$(FSharpTestCompilerVersion)' == '' "/>
   <Import Project="FSharpTests.Directory.Build.targets" Condition = " '$(FSharpTestCompilerVersion)' != '' "/>
   <Import Project="CoordinateXliff.targets" Condition = " '$(FSharpBuildAssemblyFile)' != '' and '$(XliffTasksAssembly)' != '' "/>

eng/targets/Bootstrap.targets

@@ -0,0 +1,92 @@
+<Project>
+
+  <!--
+    Bootstrap.targets
+
+    Automatically builds the bootstrap compiler when needed for FSharp.sln.
+
+    Goals:
+    - dotnet build FSharp.sln works without scripts
+    - Bootstrap runs automatically on first build (if missing)
+    - Bootstrap errors surface as proper MSBuild errors
+    - Bootstrap output is silent on success
+    - Skips bootstrap when not needed (Proto config, SDK compiler mode, etc.)
+  -->
+
+  <PropertyGroup>
+    <!-- Bootstrap output directory -->
+    <BootstrapDir>$(ArtifactsDir)Bootstrap\</BootstrapDir>
+
+    <!-- Bootstrap tool paths -->
+    <FsLexBootstrapPath>$(BootstrapDir)fslex\fslex.dll</FsLexBootstrapPath>
+    <FsYaccBootstrapPath>$(BootstrapDir)fsyacc\fsyacc.dll</FsYaccBootstrapPath>
+    <FscBootstrapPath>$(BootstrapDir)fsc\fsc.dll</FscBootstrapPath>
+
+    <!-- Skip bootstrap when:
+         - Configuration is Proto (we ARE the bootstrap)
+         - DisableCompilerRedirection is true (user wants SDK compiler)
+         - BUILDING_USING_DOTNET is true (FSharp.Compiler.Service.sln uses SDK compiler)
+         - MSBuildProjectDirectory is under artifacts (test/temp projects, build outputs)
+    -->
+    <_SkipBootstrap Condition="'$(Configuration)' == 'Proto'">true</_SkipBootstrap>
+    <_SkipBootstrap Condition="'$(DisableCompilerRedirection)' == 'true'">true</_SkipBootstrap>
+    <_SkipBootstrap Condition="'$(BUILDING_USING_DOTNET)' == 'true'">true</_SkipBootstrap>
+    <_SkipBootstrap Condition="$(MSBuildProjectDirectory.StartsWith('$(ArtifactsDir)'))">true</_SkipBootstrap>
+  </PropertyGroup>
+
+  <!--
+    Target: _CheckBootstrapNeeded
+
+    Runs before Restore and Build to check if bootstrap compiler exists.
+    If any of the bootstrap tools are missing, triggers bootstrap build.
+  -->
+  <Target Name="_CheckBootstrapNeeded" 
+          BeforeTargets="Restore;Build" 
+          Condition="'$(_SkipBootstrap)' != 'true'">
+
+    <PropertyGroup>
+      <_BootstrapNeeded>false</_BootstrapNeeded>
+      <_BootstrapNeeded Condition="!Exists('$(FsLexBootstrapPath)')">true</_BootstrapNeeded>
+      <_BootstrapNeeded Condition="!Exists('$(FsYaccBootstrapPath)')">true</_BootstrapNeeded>
+      <_BootstrapNeeded Condition="!Exists('$(FscBootstrapPath)')">true</_BootstrapNeeded>
+    </PropertyGroup>
+
+    <CallTarget Targets="_RunBootstrap" Condition="'$(_BootstrapNeeded)' == 'true'" />
+  </Target>
+
+  <!--
+    Target: _RunBootstrap
+
+    Builds the bootstrap compiler by publishing proto.proj.
+    Uses minimal verbosity for clean CI logs.
+    On failure, emits MSBuild error that stops the build.
+  -->
+  <Target Name="_RunBootstrap">
+    <Message Text="Building bootstrap compiler..." Importance="high" />
+
+    <Exec Command="dotnet publish &quot;$(RepoRoot)proto.proj&quot; -c Proto -v:minimal"
+          IgnoreExitCode="true"
+          ConsoleToMSBuild="true">
+      <Output TaskParameter="ExitCode" PropertyName="_BootstrapExitCode" />
+    </Exec>
+
+    <Error Text="Bootstrap build failed. Check output above." 
+           Condition="'$(_BootstrapExitCode)' != '0'" />
+
+    <Message Text="Bootstrap complete." 
+             Importance="high" 
+             Condition="'$(_BootstrapExitCode)' == '0'" />
+  </Target>
+
+  <!--
+    Target: RebuildBootstrap
+
+    Public target to force rebuild of bootstrap compiler.
+    Usage: dotnet build /t:RebuildBootstrap
+  -->
+  <Target Name="RebuildBootstrap">
+    <RemoveDir Directories="$(BootstrapDir)" />
+    <CallTarget Targets="_RunBootstrap" />
+  </Target>
+
+</Project>

proto.proj

@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <RootDir Condition="'$(RootDir)'==''">Bootstrap</RootDir>
+    <NETCORE_ENGINEERING_TELEMETRY>Bootstrap</NETCORE_ENGINEERING_TELEMETRY>
   </PropertyGroup>
 
   <ItemGroup>