ci: install .NET and NuGet packages on a faster drive on Windows

.github/actions/environment/action.yml

@@ -93,8 +93,11 @@ runs:
         dotnet workload restore \
           --temp-dir "${{ runner.temp }}" \
           --skip-sign-check
-        dotnet workload restore test/AndroidTestApp/AndroidTestApp.csproj \
-          --temp-dir "${{ runner.temp }}" \
-          --skip-sign-check
-        # Restore the Android test app explicitly to ensure runtime packs are available
-        dotnet restore test/AndroidTestApp/AndroidTestApp.csproj -r android-x64 --nologo || true
+        # The Windows solution filters exclude the Android test app and the tests that build it
+        if [[ "$RUNNER_OS" != "Windows" ]]; then
+          dotnet workload restore test/AndroidTestApp/AndroidTestApp.csproj \
+            --temp-dir "${{ runner.temp }}" \
+            --skip-sign-check
+          # Restore the Android test app explicitly to ensure runtime packs are available
+          dotnet restore test/AndroidTestApp/AndroidTestApp.csproj -r android-x64 --nologo || true
+        fi

.github/actions/windows-dotnet-drive/action.yml

@@ -0,0 +1,42 @@
+name: Windows .NET drive
+description: Installs .NET and the NuGet packages on a fast drive on Windows runners
+runs:
+  using: composite
+
+  steps:
+    # The Windows images keep .NET under Program Files, where workloads install as MSI packages, and the NuGet cache
+    # in the user profile on C:. So .NET goes next to the workspace, where workloads install as plain files. The x64
+    # runners put the workspace on D:, so the NuGet packages go there too. The arm64 runners only have C:, so the
+    # NuGet packages and TEMP go on a Dev Drive there. Defender already excludes C:\ on these images.
+    - name: Install .NET and NuGet packages on a fast drive
+      shell: pwsh
+      run: |
+        $root = Split-Path $env:GITHUB_WORKSPACE
+        "DOTNET_INSTALL_DIR=$root\.dotnet" >> $env:GITHUB_ENV
+        if ($root.StartsWith('C:'))
+        {
+            # Only volumes mounted after this get no antivirus filters
+            fsutil devdrv enable /disallowAv | Out-Host
+            'create vdisk file="C:\devdrive.vhdx" maximum=81920 type=expandable', 'select vdisk file="C:\devdrive.vhdx"', 'attach vdisk', 'convert gpt', 'create partition primary' |
+                Set-Content "$env:RUNNER_TEMP\diskpart.txt"
+            diskpart /s "$env:RUNNER_TEMP\diskpart.txt" | Out-Host
+            if ($LASTEXITCODE -ne 0) { throw "diskpart failed with exit code $LASTEXITCODE" }
+            $partition = Get-DiskImage -ImagePath 'C:\devdrive.vhdx' | Get-Disk | Get-Partition | Where-Object Type -eq 'Basic'
+            $partition | Format-Volume -DevDrive -Confirm:$false -Force | Out-Host
+            $partition | Add-PartitionAccessPath -AccessPath 'X:\'
+            # Right after the mount, trust can fail with "Access is denied" while the volume is still in use
+            for ($attempt = 1; $attempt -le 5; $attempt++)
+            {
+                fsutil devdrv trust X: | Out-Host
+                if ($LASTEXITCODE -eq 0) { break }
+                Start-Sleep -Seconds 3
+            }
+            if ($LASTEXITCODE -ne 0) { Write-Warning "Couldn't mark X: as a trusted Dev Drive, so antivirus filters may still scan it" }
+            fsutil devdrv query X: | Out-Host
+            $root = 'X:'
+            New-Item -ItemType Directory "$root\tmp" | Out-Null
+            "TEMP=$root\tmp" >> $env:GITHUB_ENV
+            "TMP=$root\tmp" >> $env:GITHUB_ENV
+        }
+        "NUGET_PACKAGES=$root\.nuget\packages" >> $env:GITHUB_ENV
+        $global:LASTEXITCODE = 0

.github/workflows/build.yml

@@ -143,6 +143,10 @@ jobs:
         if: ${{ !matrix.container }}
         uses: ./.github/actions/freediskspace
 
+      - name: Install .NET and NuGet packages on a fast drive
+        if: runner.os == 'Windows'
+        uses: ./.github/actions/windows-dotnet-drive
+
       - name: Setup Environment
         uses: ./.github/actions/environment
 
@@ -347,6 +351,9 @@ jobs:
         with:
           submodules: recursive
 
+      - name: Install .NET and NuGet packages on a fast drive
+        uses: ./.github/actions/windows-dotnet-drive
+
       - name: Download sentry-native (win-x64)
         uses: actions/cache/restore@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/verify-api.yml

@@ -42,6 +42,10 @@ jobs:
       - name: Remove unused applications
         uses: ./.github/actions/freediskspace
 
+      - name: Install .NET and NuGet packages on a fast drive
+        if: runner.os == 'Windows'
+        uses: ./.github/actions/windows-dotnet-drive
+
       - name: Setup Environment
         uses: ./.github/actions/environment