Install Windows Python 3.16+ from release manifest packages

builders/win-python-builder.psm1

@@ -25,6 +25,7 @@ class WinPythonBuilder : PythonBuilder {
     [string] $InstallationTemplateName
     [string] $InstallationScriptName
     [string] $OutputArtifactName
+    [string] $PackageLocation
 
     WinPythonBuilder(
         [semver] $version,
@@ -36,6 +37,80 @@ class WinPythonBuilder : PythonBuilder {
         $this.OutputArtifactName = "python-$Version-$Platform-$Architecture.zip"
     }
 
+    [bool] UsesPackageManifest() {
+        <#
+        .SYNOPSIS
+        Python 3.16+ no longer ships legacy Windows installers (PEP 773), only packages listed in a release manifest.
+        #>
+
+        return $this.Version.Major -eq 3 -and $this.Version.Minor -ge 16
+    }
+
+    [string] GetManifestPackageId([string] $package, [bool] $freethreaded) {
+        <#
+        .SYNOPSIS
+        Return the id of a package ("pythoncore" or "pythontest") in the Windows release manifest for this architecture.
+        #>
+
+        $hardware = switch ($this.GetHardwareArchitecture()) {
+            "x86" { "32" }
+            "x64" { "64" }
+            "arm64" { "arm64" }
+            default { throw "Unsupported architecture: $($this.Architecture)" }
+        }
+        $suffix = if ($freethreaded) { "t" } else { "" }
+
+        return "${package}-$($this.Version.Major).$($this.Version.Minor)${suffix}-${hardware}"
+    }
+
+    [uri] GetManifestUri() {
+        <#
+        .SYNOPSIS
+        Return URI of the Windows release manifest, e.g. windows-3.16.0a1.json
+        #>
+
+        $base = $this.GetBaseUri()
+        $versionName = $this.GetBaseVersion()
+        $nativeVersion = Convert-Version -version $this.Version
+
+        return "${base}/${versionName}/windows-${nativeVersion}.json"
+    }
+
+    [object] GetManifest() {
+        <#
+        .SYNOPSIS
+        Download and parse the Windows release manifest.
+        #>
+
+        $manifestUri = $this.GetManifestUri()
+        Write-Host "Manifest URI: $manifestUri"
+
+        return Invoke-RestMethod -Uri $manifestUri
+    }
+
+    [string] DownloadPackage([object] $manifest, [string] $packageId) {
+        <#
+        .SYNOPSIS
+        Download a package listed in the Windows release manifest and validate its SHA-256 hash.
+        #>
+
+        $package = $manifest.versions | Where-Object { $_.id -eq $packageId }
+        if ($null -eq $package) {
+            throw "Package '$packageId' not found in the Windows release manifest"
+        }
+
+        Write-Host "Sources URI: $($package.url)"
+        $packagePath = Download-File -Uri $package.url -OutputFolder $this.WorkFolderLocation
+        Write-Debug "Done; Sources location: $packagePath"
+
+        $actualHash = (Get-FileHash -Path $packagePath -Algorithm SHA256).Hash
+        if ($actualHash -ne $package.hash.sha256) {
+            throw "SHA-256 mismatch for $($package.url): expected $($package.hash.sha256), got $actualHash"
+        }
+
+        return $packagePath
+    }
+
     [string] GetPythonExtension() {
         <#
         .SYNOPSIS
@@ -84,6 +159,21 @@ class WinPythonBuilder : PythonBuilder {
         Download Python installation executable into artifact location.
         #>
 
+        if ($this.UsesPackageManifest()) {
+            $manifest = $this.GetManifest()
+
+            # The "pythontest" package is "pythoncore" plus Lib/test, for consistency with the legacy installers.
+            $packageId = $this.GetManifestPackageId("pythontest", $this.IsFreeThreaded())
+
+            # 3.16.0a1 has no free-threaded "pythontest" package, so fall back to "pythoncore" (no Lib/test) for those.
+            if (-not ($manifest.versions | Where-Object { $_.id -eq $packageId })) {
+                Write-Host "Package '$packageId' not found, using 'pythoncore' instead"
+                $packageId = $this.GetManifestPackageId("pythoncore", $this.IsFreeThreaded())
+            }
+
+            return $this.DownloadPackage($manifest, $packageId)
+        }
+
         $sourceUri = $this.GetSourceUri()
 
         Write-Host "Sources URI: $sourceUri"
@@ -99,8 +189,12 @@ class WinPythonBuilder : PythonBuilder {
         Create Python artifact installation script based on specified template.
         #>
 
-        $sourceUri = $this.GetSourceUri()
-        $pythonExecName = [IO.path]::GetFileName($sourceUri.AbsoluteUri)
+        if ($this.UsesPackageManifest()) {
+            $pythonExecName = [IO.path]::GetFileName($this.PackageLocation)
+        } else {
+            $sourceUri = $this.GetSourceUri()
+            $pythonExecName = [IO.path]::GetFileName($sourceUri.AbsoluteUri)
+        }
         $installationTemplateLocation = Join-Path -Path $this.InstallationTemplatesLocation -ChildPath $this.InstallationTemplateName
         $installationTemplateContent = Get-Content -Path $installationTemplateLocation -Raw
         $installationScriptLocation = New-Item -Path $this.WorkFolderLocation -Name $this.InstallationScriptName -ItemType File
@@ -129,7 +223,7 @@ class WinPythonBuilder : PythonBuilder {
         #>
 
         Write-Host "Download Python $($this.Version) [$($this.Architecture)] executable..."
-        $this.Download()
+        $this.PackageLocation = $this.Download()
 
         Write-Host "Create installation script..."
         $this.CreateInstallationScript()

installers/win-setup-template.ps1

@@ -83,6 +83,7 @@ $PythonToolcachePath = Join-Path -Path $ToolcacheRoot -ChildPath "Python"
 $PythonVersionPath = Join-Path -Path $PythonToolcachePath -ChildPath $Version
 $PythonArchPath = Join-Path -Path $PythonVersionPath -ChildPath $Architecture
 
+$IsZip = $PythonExecName -match "\.zip$"
 $IsMSI = $PythonExecName -match "msi"
 $IsFreeThreaded = $Architecture -match "-freethreaded"
 
@@ -114,27 +115,38 @@ if ($null -ne $InstalledVersions) {
     Write-Host "No Python$MajorVersion.$MinorVersion.* found"
 }
 
-Write-Host "Remove registry entries for Python ${MajorVersion}.${MinorVersion}(${Architecture})..."
-Remove-RegistryEntries -Architecture $Architecture -MajorVersion $MajorVersion -MinorVersion $MinorVersion
+if (-not $IsZip) {
+    Write-Host "Remove registry entries for Python ${MajorVersion}.${MinorVersion}(${Architecture})..."
+    Remove-RegistryEntries -Architecture $Architecture -MajorVersion $MajorVersion -MinorVersion $MinorVersion
+}
 
 Write-Host "Create Python $Version folder in $PythonToolcachePath"
 New-Item -ItemType Directory -Path $PythonArchPath -Force | Out-Null
 
-Write-Host "Copy Python binaries to $PythonArchPath"
-Copy-Item -Path ./$PythonExecName -Destination $PythonArchPath | Out-Null
+if ($IsZip) {
+    # Python 3.16+ is distributed as a package (PEP 773) that can be extracted and run as-is
+    Write-Host "Extract Python $Version in $PythonToolcachePath..."
+    Expand-Archive -Path ./$PythonExecName -DestinationPath $PythonArchPath -Force
 
-Write-Host "Install Python $Version in $PythonToolcachePath..."
-$ExecParams = Get-ExecParams -IsMSI $IsMSI -IsFreeThreaded $IsFreeThreaded -PythonArchPath $PythonArchPath
+    # Debug symbols are only in the "pythontest" package and were not installed by the legacy installers
+    Get-ChildItem -Path $PythonArchPath -Recurse -Filter "*.pdb" | Remove-Item -Force
+} else {
+    Write-Host "Copy Python binaries to $PythonArchPath"
+    Copy-Item -Path ./$PythonExecName -Destination $PythonArchPath | Out-Null
 
-cmd.exe /c "cd $PythonArchPath && call $PythonExecName $ExecParams /quiet"
-if ($LASTEXITCODE -ne 0) {
-    Throw "Error happened during Python installation"
-}
+    Write-Host "Install Python $Version in $PythonToolcachePath..."
+    $ExecParams = Get-ExecParams -IsMSI $IsMSI -IsFreeThreaded $IsFreeThreaded -PythonArchPath $PythonArchPath
 
-if ($IsFreeThreaded) {
-    # Delete python.exe and create a symlink to free-threaded exe
-    Remove-Item -Path "$PythonArchPath\python.exe" -Force
-    New-Item -Path "$PythonArchPath\python.exe" -ItemType SymbolicLink -Value "$PythonArchPath\python${MajorVersion}.${MinorVersion}t.exe"
+    cmd.exe /c "cd $PythonArchPath && call $PythonExecName $ExecParams /quiet"
+    if ($LASTEXITCODE -ne 0) {
+        Throw "Error happened during Python installation"
+    }
+
+    if ($IsFreeThreaded) {
+        # Delete python.exe and create a symlink to free-threaded exe
+        Remove-Item -Path "$PythonArchPath\python.exe" -Force
+        New-Item -Path "$PythonArchPath\python.exe" -ItemType SymbolicLink -Value "$PythonArchPath\python${MajorVersion}.${MinorVersion}t.exe"
+    }
 }
 
 Write-Host "Create `python3` symlink"

tests/python-tests.ps1

@@ -66,6 +66,32 @@ Describe "Tests" {
         }
     }
 
+    # Windows free-threaded Python 3.16+ is installed from a "PythonCore" package, as there is no free-threaded "PythonTest" package with Lib/test
+    $SkipTestSuite = ($Platform -eq "win32") -and ($Architecture -match "-freethreaded") -and ([semver]$Version -ge [semver]"3.16.0-alpha.1")
+    It "Check if the standard library test suite (Lib/test) is installed" -Skip:$SkipTestSuite {
+        "python ./sources/stdlib-test-suite.py" | Should -ReturnZeroExitCode
+    }
+
+    if ($Platform -eq "win32") {
+        It "pip.exe is from the toolcache" {
+            $pipLocation = (Get-Command "pip").Path
+            $pipLocation | Should -Not -BeNullOrEmpty
+            $expectedPath = Join-Path -Path $env:RUNNER_TOOL_CACHE -ChildPath "Python"
+            $pipLocation.startsWith($expectedPath) | Should -BeTrue
+        }
+
+        # TODO: Python 3.16+ is extracted from a package, so it is not registered for the legacy py.exe launcher
+        $SkipPyLauncher = [semver]$Version -ge [semver]"3.16.0-alpha.1"
+        It "py.exe finds Python" -Skip:$SkipPyLauncher {
+            $suffix = if ($Architecture -match "-freethreaded") { "t" } else { "" }
+            $major, $minor = "$Version".Split(".")[0..1]
+            $pyLocation = py "-$major.$minor$suffix" -c "import sys; print(sys.executable)"
+            $LASTEXITCODE | Should -Be 0
+            $expectedPath = Join-Path -Path $env:RUNNER_TOOL_CACHE -ChildPath "Python"
+            $pyLocation.startsWith($expectedPath) | Should -BeTrue
+        }
+    }
+
     It "Run pip" {
         "pip install requests" | Should -ReturnZeroExitCode
         "pip uninstall requests -y" | Should -ReturnZeroExitCode

tests/sources/stdlib-test-suite.py

@@ -0,0 +1,19 @@
+import importlib.util
+import os.path
+import sys
+
+
+def check_test_suite():
+    spec = importlib.util.find_spec("test")
+    if spec is None or not spec.submodule_search_locations:
+        print("The 'test' package (Lib/test) is not installed")
+        sys.exit(1)
+
+    test_dir = list(spec.submodule_search_locations)[0]
+    for name in ("support", "libregrtest"):
+        if not os.path.isdir(os.path.join(test_dir, name)):
+            print("Missing test.{} in {}".format(name, test_dir))
+            sys.exit(1)
+
+
+check_test_suite()