feat: Windows filtering and sets

Co-authored-by: Matthieu Darbois <mayeut@users.noreply.github.com>

cibuildwheel/windows.py

@@ -5,7 +5,7 @@ import sys
 import tempfile
 import textwrap
 from pathlib import Path
-from typing import Dict, List, NamedTuple, Optional, Sequence
+from typing import Dict, List, NamedTuple, Optional, Sequence, Set
 from zipfile import ZipFile
 
 import toml
@@ -48,7 +48,12 @@ class PythonConfiguration(NamedTuple):
     url: Optional[str]
 
 
-def get_python_configurations(build_selector: BuildSelector) -> List[PythonConfiguration]:
+def get_python_configurations(build_selector: BuildSelector, architectures: Set[Architecture]) -> List[PythonConfiguration]:
+    map_arch = {
+        '32': Architecture.x86,
+        '64': Architecture.AMD64,
+    }
+
     python_configurations = [
         # CPython
         PythonConfiguration(version='2.7.18', arch='32', identifier='cp27-win32', url=None),
@@ -75,7 +80,10 @@ def get_python_configurations(build_selector: BuildSelector) -> List[PythonConfi
         python_configurations = [c for c in python_configurations if not c.version.startswith('2.7')]
 
     # skip builds as required
-    python_configurations = [c for c in python_configurations if build_selector(c.identifier)]
+    python_configurations = [
+        c for c in python_configurations
+        if build_selector(c.identifier) and map_arch[c.arch] in architectures
+    ]
 
     return python_configurations
 
@@ -202,11 +210,12 @@ def pep_518_cp35_workaround(package_dir: Path, env: Dict[str, str]) -> None:
 
 
 def build(options: BuildOptions) -> None:
-    if options.architectures != [Architecture.AMD64, Architecture.x86]:
+    allowed_architectures = {Architecture.AMD64, Architecture.x86}
+    if not options.architectures <= allowed_architectures:
         raise ValueError(textwrap.dedent(f'''
-            Invalid archs option {options.architectures}. Windows only supports 'amd64,x86' for the
-            moment. If you want to set emulation architectures on Linux, use CIBW_ARCHS_LINUX
-            instead.
+            Invalid archs option {options.architectures}. Windows only supports
+            {sorted(allowed_architectures)}. If you want to set emulation
+            architectures on Linux, use CIBW_ARCHS_LINUX instead.
         '''))
 
     temp_dir = Path(tempfile.mkdtemp(prefix='cibuildwheel'))
@@ -220,7 +229,7 @@ def build(options: BuildOptions) -> None:
             before_all_prepared = prepare_command(options.before_all, project='.', package=options.package_dir)
             shell(before_all_prepared, env=env)
 
-        python_configurations = get_python_configurations(options.build_selector)
+        python_configurations = get_python_configurations(options.build_selector, options.architectures)
 
         for config in python_configurations:
             log.build_start(config.identifier)