Add missing eng/SetApexRoslynVersion.ps1 for the Apex Roslyn detectio…

…n step The azure-pipelines-PR.yml 'Detect CI VS Roslyn version' step and the FSHARP_APEX_ROSLYN_VERSION override in eng/Versions.props were committed, but the script itself was left untracked, so on CI 'powershell: eng\SetApexRoslynVersion.ps1' could not find the file and failed with 'The module ''eng'' could not be loaded'. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: fe2b3239-4176-4f13-b6f6-486c8799765a
abonie · Oct 8, 2026 · Jul 12, 2026 · Jul 15, 2026 · Jul 22, 2026 · Jul 23, 2026
commit 1596a31e2de1c5c30c9090e20c924cb70c7b6a38
diff --git a/eng/SetApexRoslynVersion.ps1 b/eng/SetApexRoslynVersion.ps1
@@ -0,0 +1,82 @@
+# Detects the Roslyn version of the *installed* Visual Studio and exports it as the pipeline variable
+# FSHARP_APEX_ROSLYN_VERSION so the Apex integration-test leg builds the F# VSIX against it.
+#
+# Why: the repo pins Roslyn forward (to the VS being inserted into), which is newer than any VS on the CI
+# scout image. A VSIX built against that pin cannot bind Microsoft.VisualStudio.LanguageServices at
+# runtime in the older CI VS, so FSharpPackage/FSharpProjectPackage fail to load and every Apex test
+# fails. The F# editor references Roslyn compile-only (ExcludeAssets=runtime), so building against the
+# VS's own Roslyn version is sufficient and ships nothing extra. The eng/Versions.props override consumes
+# this variable; the committed pin is unchanged. If detection fails we leave the variable unset (the
+# build falls back to the committed pin) rather than break the build.
+[CmdletBinding()]
+param()
+
+$ErrorActionPreference = 'Stop'
+
+function Write-Skip([string] $message) {
+    Write-Host "##vso[task.logissue type=warning]$message"
+    Write-Host "Apex Roslyn override not set; the VSIX will build against the repo's pinned Roslyn."
+}
+
+$vswhere = Join-Path ${env:ProgramFiles(x86)} 'Microsoft Visual Studio\Installer\vswhere.exe'
+if (-not (Test-Path $vswhere)) {
+    Write-Skip "vswhere.exe not found; cannot detect the installed VS Roslyn version."
+    return
+}
+
+# Select the same install the Apex gate runs against: the lowest matching (default major '18') VS that
+# actually has devenv.exe. On CI there is a single VS, so any selection resolves to it.
+$prefix = if (${env:FSHARP_APEX_VS_VERSION}) { ${env:FSHARP_APEX_VS_VERSION} } else { '18' }
+$versions = @(& $vswhere -all -prerelease -products * -property installationVersion)
+$paths    = @(& $vswhere -all -prerelease -products * -property installationPath)
+
+$candidates = for ($i = 0; $i -lt $versions.Count; $i++) {
+    if ($versions[$i] -like "$prefix.*") {
+        [PSCustomObject]@{ Version = $versions[$i]; Path = $paths[$i] }
+    }
+}
+$candidates = @($candidates | Sort-Object { [version]$_.Version })
+
+$vsDir = $null
+foreach ($c in $candidates) {
+    if (Test-Path (Join-Path $c.Path 'Common7\IDE\devenv.exe')) { $vsDir = $c.Path.TrimEnd('\'); break }
+}
+if (-not $vsDir) {
+    Write-Skip "No installed VS $prefix.x with devenv.exe found; cannot detect the Roslyn version."
+    return
+}
+
+$lsDll = Join-Path $vsDir 'Common7\IDE\CommonExtensions\Microsoft\VBCSharp\LanguageServices\Microsoft.VisualStudio.LanguageServices.dll'
+if (-not (Test-Path $lsDll)) {
+    $lsDll = Get-ChildItem -Path $vsDir -Recurse -Filter 'Microsoft.VisualStudio.LanguageServices.dll' -ErrorAction SilentlyContinue |
+        Select-Object -First 1 -ExpandProperty FullName
+}
+if (-not $lsDll -or -not (Test-Path $lsDll)) {
+    Write-Skip "Microsoft.VisualStudio.LanguageServices.dll not found under '$vsDir'."
+    return
+}
+
+$asmVersion = [System.Reflection.AssemblyName]::GetAssemblyName($lsDll).Version
+$majorMinor = "$($asmVersion.Major).$($asmVersion.Minor)"
+Write-Host "Installed VS '$vsDir' ships Roslyn assembly $asmVersion (major.minor $majorMinor)."
+
+# Resolve a matching Microsoft.CodeAnalysis NuGet version. The whole Roslyn family is published together
+# with the same version, and every '<major>.<minor>.0-*' build has assembly version <major>.<minor>.0.0,
+# so any such package binds to the installed VS at runtime; pick the newest for freshness.
+$feed = 'https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3'
+try {
+    $allVersions = (Invoke-RestMethod -Uri "$feed/flat2/microsoft.codeanalysis.externalaccess.fsharp/index.json" -UseBasicParsing).versions
+} catch {
+    Write-Skip "Failed to query the dotnet-tools feed for Roslyn versions: $($_.Exception.Message)"
+    return
+}
+
+$selected = @($allVersions | Where-Object { $_ -match "^$([regex]::Escape($majorMinor))\.0-" }) |
+    Sort-Object | Select-Object -Last 1
+if (-not $selected) {
+    Write-Skip "No Roslyn package '$majorMinor.0-*' found on the feed to match the installed VS."
+    return
+}
+
+Write-Host "Selected Roslyn NuGet version '$selected' for the Apex VSIX build (matches VS Roslyn $majorMinor)."
+Write-Host "##vso[task.setvariable variable=FSHARP_APEX_ROSLYN_VERSION]$selected"