Run the CMake smoke test on Windows

This would have caught a recent regression.

Author: jakepetroules

.github/scripts/windows_pre_build.ps1

@@ -0,0 +1,37 @@
+##===----------------------------------------------------------------------===##
+##
+## This source file is part of the Swift open source project
+##
+## Copyright (c) 2025 Apple Inc. and the Swift project authors
+## Licensed under Apache License v2.0 with Runtime Library Exception
+##
+## See http://swift.org/LICENSE.txt for license information
+## See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+##
+##===----------------------------------------------------------------------===##
+
+param (
+    [switch]$SkipAndroid,
+    [switch]$InstallCMake
+)
+
+# winget isn't easily made available in containers, so use chocolatey
+Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))
+
+if ($InstallCMake) {
+    choco install -y cmake --installargs 'ADD_CMAKE_TO_PATH=System' --apply-install-arguments-to-dependencies
+    choco install -y ninja
+
+    Import-Module $env:ChocolateyInstall\helpers\chocolateyProfile.psm1
+    refreshenv
+}
+
+if (-not $SkipAndroid) {
+    choco install android-ndk
+
+    Import-Module $env:ChocolateyInstall\helpers\chocolateyProfile.psm1
+    refreshenv
+
+    # Work around a bug in the package causing the env var to be set incorrectly
+    $env:ANDROID_NDK_ROOT = $env:ANDROID_NDK_ROOT.replace('-windows.zip','')
+}

.github/workflows/pull_request.yml

@@ -29,7 +29,10 @@ jobs:
       linux_pre_build_command: SKIP_ANDROID=1 INSTALL_CMAKE=1 ./.github/scripts/linux_pre_build.sh
       linux_build_command: 'swift package -Xbuild-tools-swiftc -DUSE_PROCESS_SPAWNING_WORKAROUND cmake-smoke-test --disable-sandbox --cmake-path `which cmake` --ninja-path `which ninja` --extra-cmake-arg -DCMAKE_C_COMPILER=`which clang` --extra-cmake-arg -DCMAKE_CXX_COMPILER=`which clang++` --extra-cmake-arg -DCMAKE_Swift_COMPILER=`which swiftc`'
       linux_swift_versions: '["nightly-main"]'
-      windows_swift_versions: '[]'
+      windows_pre_build_command: 'Invoke-Program .\.github\scripts\windows_pre_build.ps1 -SkipAndroid -InstallCMake'
+      windows_swift_versions: '["nightly-main"]'
+      windows_build_command: 'Invoke-Program swift package -Xbuild-tools-swiftc cmake-smoke-test --disable-sandbox --cmake-path (Get-Command cmake).Path --ninja-path (Get-Command ninja).Path --extra-cmake-arg -DCMAKE_C_COMPILER=(Get-Command clang).Path --extra-cmake-arg -DCMAKE_CXX_COMPILER=(Get-Command clang++).Path --extra-cmake-arg -DCMAKE_Swift_COMPILER=(Get-Command swiftc).Path'
+
   soundness:
     name: Soundness
     uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main

Plugins/cmake-smoke-test/cmake-smoke-test.swift

@@ -187,7 +187,7 @@ extension Process {
 
     static func checkNonZeroExit(url: URL, arguments: [String], workingDirectory: URL, environment: [String: String]? = nil) async throws {
         Diagnostics.progress("\(url.path()) \(arguments.joined(separator: " "))")
-        #if USE_PROCESS_SPAWNING_WORKAROUND
+        #if USE_PROCESS_SPAWNING_WORKAROUND && !os(Windows)
         Diagnostics.progress("Using process spawning workaround")
         // Linux workaround for https://github.com/swiftlang/swift-corelibs-foundation/issues/4772
         // Foundation.Process on Linux seems to inherit the Process.run()-calling thread's signal mask, creating processes that even have SIGTERM blocked
@@ -246,6 +246,7 @@ extension Process {
     }
 }
 
+#if USE_PROCESS_SPAWNING_WORKAROUND && !os(Windows)
 func scan<S: Sequence, U>(_ seq: S, _ initial: U, _ combine: (U, S.Element) -> U) -> [U] {
   var result: [U] = []
   result.reserveCapacity(seq.underestimatedCount)
@@ -283,3 +284,4 @@ func withArrayOfCStrings<T>(
     }
   }
 }
+#endif