Check available features in Windows wheels

.github/workflows/test-windows.yml

@@ -235,6 +235,12 @@ jobs:
         %pythonLocation%\python.exe -m pip wheel -v -C raqm=vendor -C fribidi=vendor -C imagequant=disable .
       shell: cmd
 
+    - name: Test Wheel
+      if: "github.event_name != 'pull_request'"
+      run: |
+        docker run --rm -v ${env:GITHUB_WORKSPACE}:C:\pillow mcr.microsoft.com/windows/servercore:ltsc2022 powershell C:\pillow\winbuild\test_docker.ps1 ${{ matrix.python-version }}
+      shell: pwsh
+
     - name: Upload wheel
       uses: actions/upload-artifact@v3
       if: "github.event_name != 'pull_request'"

Tests/check_wheel.py

@@ -0,0 +1,24 @@
+import sys
+
+import pytest
+
+from PIL import features
+
+
+@pytest.mark.skipif(sys.platform != "win32", reason="requires Windows")
+def test_windows_wheel_features():
+    expected_modules = ["pil", "tkinter", "freetype2", "littlecms2", "webp"]
+    expected_codecs = ["jpg", "jpg_2000", "zlib", "libtiff"]
+    expected_features = [
+        "webp_anim",
+        "webp_mux",
+        "transp_webp",
+        "raqm",
+        "fribidi",
+        "harfbuzz",
+        "libjpeg_turbo",
+    ]
+
+    assert features.get_supported_modules() == expected_modules
+    assert features.get_supported_codecs() == expected_codecs
+    assert features.get_supported_features() == expected_features

Tests/test_imagegrab.py

@@ -15,6 +15,8 @@
         sys.platform not in ("win32", "darwin"), reason="requires Windows or macOS"
     )
     def test_grab(self):
+        if os.environ.get("USERNAME") == "ContainerAdministrator":
+            pytest.skip("can't grab screen when running in Docker")
         ImageGrab.grab()
         ImageGrab.grab(include_layered_windows=True)
         ImageGrab.grab(all_screens=True)

winbuild/test_docker.ps1

@@ -0,0 +1,38 @@
+param ([string]$python)
+$ErrorActionPreference  = 'Stop'
+$ProgressPreference = 'SilentlyContinue'
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+if ($python -like "pypy*") {
+    echo "Downloading https://aka.ms/vs/15/release/vc_redist.x64.exe"
+    Invoke-WebRequest -Uri 'https://aka.ms/vs/15/release/vc_redist.x64.exe' -OutFile 'vc_redist.x64.exe'
+    C:\vc_redist.x64.exe /install /quiet /norestart | Out-Null
+    $url = 'https://downloads.python.org/pypy/{0}-v7.3.13-win64.zip' -f $python
+    echo "Downloading $url"
+    Invoke-WebRequest -Uri $url -OutFile 'pypy.zip'
+    tar -xf 'pypy.zip'
+    mv pypy*-win64 C:\Python
+} else {
+    $url = 'https://www.python.org/ftp/python/{0}.0/python-{0}.0-amd64.exe' -f $python
+    echo "Downloading $url"
+    Invoke-WebRequest -Uri $url -OutFile 'setup.exe'
+    Start-Process setup.exe -Wait -NoNewWindow -PassThru -ArgumentList @(
+            '/quiet',
+            'InstallAllUsers=0',
+            'TargetDir=C:\Python',
+            'PrependPath=1',
+            'Shortcuts=0',
+            'Include_doc=0',
+            'Include_pip=1',
+            'Include_test=0'
+        )
+}
+$env:CI = "true"
+$env:path += ";C:\Python\;C:\pillow\winbuild\build\bin\"
+cd C:\pillow
+& python -VV
+& python -m ensurepip
+& python -m pip install -U pip
+& python -m pip install pytest pytest-timeout
+& python -m pip install "$(Get-ChildItem *.whl -Name)"
+& python -m pytest -vx Tests\check_wheel.py Tests
+if ((Test-Path -LiteralPath variable:\LASTEXITCODE)) { exit $LASTEXITCODE }