Skip ARM64 tests automatically with warning, and improved cleanup

cibuildwheel/windows.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import atexit
 import os
 import platform as platform_module
 import shutil
@@ -10,7 +9,7 @@ import textwrap
 from dataclasses import dataclass
 from functools import lru_cache
 from pathlib import Path
-from typing import Sequence
+from typing import Callable, Sequence
 from zipfile import ZipFile
 
 from filelock import FileLock
@@ -133,6 +132,7 @@ def setup_setuptools_cross_compile(
     python_configuration: PythonConfiguration,
     python_libs_base: Path,
     env: dict[str, str],
+    cleanup_command_list: list[Callable[[], None]],
 ) -> None:
     # We write to distutils_cfg for distutils-based builds to override some
     # settings. Ideally, we'd pass them on the command line, but since we don't
@@ -168,14 +168,14 @@ def setup_setuptools_cross_compile(
                 f"Unable to configure setuptools for cross-compiling because existing {distutils_cfg} file cannot be backed up. Error was {exc}"
             )
             return
-        atexit.register(lambda: distutils_bak.replace(distutils_cfg))
+        cleanup_command_list.append(lambda: distutils_bak.replace(distutils_cfg))
     elif distutils_cfg.is_dir():
         log.warning(
             f"Unable to configure setuptools for cross-compiling because {distutils_cfg} is a directory"
         )
         return
     else:
-        atexit.register(lambda: distutils_cfg.unlink())
+        cleanup_command_list.append(lambda: distutils_cfg.unlink())
 
     # Ensure our additional import libraries are made available, and explicitly
     # set the platform name
@@ -220,6 +220,7 @@ def setup_rust_cross_compile(
     python_configuration: PythonConfiguration,
     python_libs_base: Path,
     env: dict[str, str],
+    cleanup_command_list: list[Callable[[], None]],
 ) -> None:
     # Assume that MSVC will be used, because we already know that we are
     # cross-compiling. MinGW users can set CARGO_BUILD_TARGET themselves
@@ -250,6 +251,7 @@ def setup_python(
     dependency_constraint_flags: Sequence[PathOrStr],
     environment: ParsedEnvironment,
     build_frontend: BuildFrontend,
+    cleanup_command_list: list[Callable[[], None]],
 ) -> dict[str, str]:
     tmp.mkdir()
     implementation_id = python_configuration.identifier.split("-")[0]
@@ -371,8 +373,8 @@ def setup_python(
 
     if python_libs_base:
         # Set up the environment for various backends to enable cross-compilation
-        setup_setuptools_cross_compile(python_configuration, python_libs_base, env)
+        setup_setuptools_cross_compile(python_configuration, python_libs_base, env, cleanup_command_list)
-        setup_rust_cross_compile(python_configuration, python_libs_base, env)
+        setup_rust_cross_compile(python_configuration, python_libs_base, env, cleanup_command_list)
 
     return env
 
@@ -415,6 +417,9 @@ def build(options: Options, tmp_path: Path) -> None:
                     build_options.dependency_constraints.get_for_python_version(config.version),
                 ]
 
+            # list of callables to do any urgent cleanup, for example,
+            # config files that may bleed into other builds
+            cleanup_command_list = []
             # install Python
             env = setup_python(
                 identifier_tmp_dir / "build",
@@ -422,8 +427,10 @@ def build(options: Options, tmp_path: Path) -> None:
                 dependency_constraint_flags,
                 build_options.environment,
                 build_options.build_frontend,
+                cleanup_command_list,
             )
 
+            try:
                 compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)
                 if compatible_wheel:
                     log.step_end()
@@ -515,7 +522,24 @@ def build(options: Options, tmp_path: Path) -> None:
                     if repaired_wheel.name in {wheel.name for wheel in built_wheels}:
                         raise AlreadyBuiltWheelError(repaired_wheel.name)
 
+            finally:
+                while cleanup_command_list:
+                    cleanup_command_list.pop(0)()
+
             if build_options.test_command and options.globals.test_selector(config.identifier):
+                if config.arch == "ARM64" != platform_module.machine():
+                    log.warning(
+                        unwrap(
+                            """
+                            While arm64 wheels can be built on other platforms, they cannot
+                            be tested. An arm64 runner is required. To silence this warning,
+                            set `CIBW_TEST_SKIP: *-win_arm64`.
+                            """
+                        )
+                    )
+                    # skip this test
+                    continue
+
                 log.step("Testing wheel...")
                 # set up a virtual environment to install and test from, to make sure
                 # there are no dependencies that were pulled in at build time.

test/test_testing.py

@@ -72,13 +72,6 @@ class TestSpam(TestCase):
 '''
 
 
-ADD_ENV: dict[str, str] = {}
-
-if utils.platform == "windows":
-    if platform.machine() != "ARM64":
-        ADD_ENV["CIBW_TEST_SKIP"] = "*-win_arm64 " + ADD_ENV.get("CIBW_TEST_SKIP", "")
-
-
 def test(tmp_path):
     project_dir = tmp_path / "project"
     project_with_a_test.generate(project_dir)
@@ -92,7 +85,6 @@ def test(tmp_path):
             # mac/linux.
             "CIBW_TEST_COMMAND": "false || pytest {project}/test",
             "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || pytest {project}/test",
-            **ADD_ENV,
         },
     )
 
@@ -114,7 +106,6 @@ def test_extras_require(tmp_path):
             # mac/linux.
             "CIBW_TEST_COMMAND": "false || pytest {project}/test",
             "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || pytest {project}/test",
-            **ADD_ENV,
         },
     )
 
@@ -152,7 +143,6 @@ def test_failing_test(tmp_path):
                 # problems with this, so let's check that.
                 "CIBW_MANYLINUX_I686_IMAGE": "manylinux1",
                 "CIBW_MANYLINUX_X86_64_IMAGE": "manylinux1",
-                **ADD_ENV,
             },
         )