Deduplicate the cross-platform CI jobs

The Linux and macOS jobs were near-identical copies; their shared head
(checkout, SDK setup, version, restore, build, both test steps, test-log
upload) drifts the moment one is edited and the other is not. Collapse
them into a single platform-parameterized matrix job, and hoist the .NET
SDK version/quality and the staging directory to workflow-level env so an
SDK bump is a one-line change across all jobs.

The Windows job keeps its id (Build) so internal references stay stable,
but gains a display name to read as "Desktop (Windows)" alongside the
matrix "Desktop (linux)/(macos)" checks. Branch-protection required
checks must be repointed to the new check names.

Assisted-by: Claude:claude-opus-4-8:Claude Code

.github/workflows/build-ilspy.yml

@@ -9,8 +9,14 @@ on:
 permissions:
   contents: read
 
+env:
+  DOTNET_SDK_VERSION: '11.0.x'
+  DOTNET_SDK_QUALITY: 'preview'
+  StagingDirectory: buildartifacts
+
 jobs:
   Build:
+    name: Desktop (Windows)
     permissions:
       packages: write  # for dotnet nuget push
     runs-on: windows-2025-vs2026
@@ -20,7 +26,6 @@ jobs:
         Configuration: [ Debug, Release ]
     env:
       BuildPlatform: Any CPU
-      StagingDirectory: buildartifacts
       BuildAndPublishVsix: true
 
     defaults:
@@ -39,8 +44,8 @@ jobs:
 
     - uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '11.0.x'
-        dotnet-quality: 'preview'
+        dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
+        dotnet-quality: ${{ env.DOTNET_SDK_QUALITY }}
         cache: true
         cache-dependency-path: '**/packages.lock.json'
       env:
@@ -268,10 +273,16 @@ jobs:
   # 32-bit, roundtrip) self-exclude via Tester.SupportedOnCurrentPlatform and
   # [Platform("Win")]. ILSpy.Tests.Windows runs only in the Windows job by design.
 
-  Linux:
-    runs-on: ubuntu-latest
-    env:
-      StagingDirectory: buildartifacts
+  Desktop:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+            platform: linux
+          - os: macos-15
+            platform: macos
+    runs-on: ${{ matrix.os }}
 
     defaults:
       run:
@@ -288,8 +299,8 @@ jobs:
 
     - uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '11.0.x'
-        dotnet-quality: 'preview'
+        dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
+        dotnet-quality: ${{ env.DOTNET_SDK_QUALITY }}
         cache: true
         cache-dependency-path: '**/packages.lock.json'
       env:
@@ -333,7 +344,7 @@ jobs:
       uses: actions/upload-artifact@v7
       if: success() || failure()
       with:
-        name: test-results-linux
+        name: test-results-${{ matrix.platform }}
         path: 'test-results/*.trx'
 
     - name: Create Test Report
@@ -343,13 +354,14 @@ jobs:
         paths: "test-results/*.trx"
         folded: true
 
-    - name: Publish (linux-x64 self-contained)
-      run: ./publish.ps1 -Configuration Release -Platform linux
+    - name: Publish (self-contained)
+      run: ./publish.ps1 -Configuration Release -Platform ${{ matrix.platform }}
 
-    - name: Package (zip, deb, rpm)
-      run: ./BuildTools/package-linux.ps1 -Configuration Release -Version "${{ steps.version.outputs.ILSPY_VERSION_NUMBER }}" -StagingDirectory $env:StagingDirectory
+    - name: Package
+      run: ./BuildTools/package-${{ matrix.platform }}.ps1 -Configuration Release -Version "${{ steps.version.outputs.ILSPY_VERSION_NUMBER }}" -StagingDirectory $env:StagingDirectory
 
-    - name: Upload zip build artifact
+    - name: Upload zip build artifact (Linux)
+      if: matrix.platform == 'linux'
       uses: actions/upload-artifact@v7
       with:
         name: ILSpy Linux x64 ${{ steps.version.outputs.ILSPY_VERSION_NUMBER }} (Release)
@@ -357,6 +369,7 @@ jobs:
         if-no-files-found: error
 
     - name: Upload deb build artifact
+      if: matrix.platform == 'linux'
       uses: actions/upload-artifact@v7
       with:
         name: ILSpy Linux x64 deb ${{ steps.version.outputs.ILSPY_VERSION_NUMBER }} (Release)
@@ -364,94 +377,15 @@ jobs:
         if-no-files-found: error
 
     - name: Upload rpm build artifact
+      if: matrix.platform == 'linux'
       uses: actions/upload-artifact@v7
       with:
         name: ILSpy Linux x64 rpm ${{ steps.version.outputs.ILSPY_VERSION_NUMBER }} (Release)
         path: ${{ env.StagingDirectory }}/*.rpm
         if-no-files-found: error
 
-  macOS:
-    runs-on: macos-15
-    env:
-      StagingDirectory: buildartifacts
-
-    defaults:
-      run:
-        shell: pwsh
-
-    steps:
-    - run: mkdir -p $env:StagingDirectory
-
-    - uses: actions/checkout@v6
-      with:
-        submodules: true
-        fetch-depth: 0
-        persist-credentials: false
-
-    - uses: actions/setup-dotnet@v5
-      with:
-        dotnet-version: '11.0.x'
-        dotnet-quality: 'preview'
-        cache: true
-        cache-dependency-path: '**/packages.lock.json'
-      env:
-        DOTNET_INSTALL_DIR: ${{ runner.temp }}/.dotnet
-        DOTNET_ROOT: ${{ runner.temp }}/.dotnet
-
-    - name: Get Version
-      id: version
-      run: |
-        ./BuildTools/ghactions-install.ps1
-        Get-ChildItem Env: | Where-Object {$_.Name -Match "^ILSPY_"} | %{ echo "$($_.Name)=$($_.Value)" } | Out-File -FilePath $Env:GITHUB_OUTPUT -Encoding utf8 -Append
-
-    - name: Restore the application
-      run: >
-        dotnet restore ILSpy.Desktop.slnf
-        /p:RestoreEnablePackagePruning=false
-        /p:Configuration=Release
-        /p:Platform="Any CPU"
-
-    - name: Build
-      run: >
-        dotnet build ILSpy.Desktop.slnf --no-restore
-        -c Release
-        /p:Platform="Any CPU" /m
-
-    - name: Execute UI tests
-      run: >
-        dotnet test --project ILSpy.Tests/ILSpy.Tests.csproj
-        --configuration Release
-        --no-build --report-trx
-        --results-directory test-results
-
-    - name: Execute decompiler tests
-      run: >
-        dotnet test --project ICSharpCode.Decompiler.Tests/ICSharpCode.Decompiler.Tests.csproj
-        --configuration Release
-        --no-build --report-trx
-        --results-directory test-results
-
-    - name: Upload Test Logs
-      uses: actions/upload-artifact@v7
-      if: success() || failure()
-      with:
-        name: test-results-macos
-        path: 'test-results/*.trx'
-
-    - name: Create Test Report
-      uses: test-summary/action@v2
-      if: always()
-      with:
-        paths: "test-results/*.trx"
-        folded: true
-
-    - name: Publish (osx-arm64 self-contained app bundle)
-      run: ./publish.ps1 -Configuration Release -Platform macos
-
-    - name: Package (zipped ILSpy.app)
-      run: ./BuildTools/package-macos.ps1 -Configuration Release -Version "${{ steps.version.outputs.ILSPY_VERSION_NUMBER }}" -StagingDirectory $env:StagingDirectory
-
-    - name: Upload app bundle build artifact
+    - name: Upload app bundle build artifact (macOS)
+      if: matrix.platform == 'macos'
       uses: actions/upload-artifact@v7
       with:
         name: ILSpy macOS arm64 ${{ steps.version.outputs.ILSPY_VERSION_NUMBER }} (Release)