tests: fully type the test suite (#2794)

* tests: fully type the test suite

* chore: require more typing

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

test/conftest.py

@@ -46,7 +46,7 @@ def pytest_addoption(parser: pytest.Parser) -> None:
     )
 
 
-def pytest_configure(config):
+def pytest_configure(config: pytest.Config) -> None:
     flag_enable = config.getoption("--enable")
     flag_platform = config.getoption("--platform")
 

test/test_0_basic.py

@@ -1,4 +1,5 @@
 import textwrap
+from pathlib import Path
 
 import packaging.utils
 import pytest
@@ -21,7 +22,7 @@ basic_project = test_projects.new_c_project(
 
 
 @pytest.mark.serial
-def test_dummy_serial():
+def test_dummy_serial() -> None:
     """A no-op test to ensure that at least one serial test is always found.
 
     Without this no-op test, CI fails on CircleCI because no serial tests are
@@ -29,7 +30,9 @@ def test_dummy_serial():
     """
 
 
-def test(tmp_path, build_frontend_env, capfd):
+def test(
+    tmp_path: Path, build_frontend_env: dict[str, str], capfd: pytest.CaptureFixture[str]
+) -> None:
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
 
@@ -52,7 +55,7 @@ def test(tmp_path, build_frontend_env, capfd):
 
 
 @pytest.mark.skip(reason="to keep test output clean")
-def test_sample_build(tmp_path, capfd):
+def test_sample_build(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
 
@@ -70,7 +73,9 @@ def test_sample_build(tmp_path, capfd):
 @pytest.mark.parametrize(
     "enable_setting", ["", "cpython-prerelease", "pypy", "cpython-freethreading"]
 )
-def test_build_identifiers(tmp_path, enable_setting, monkeypatch):
+def test_build_identifiers(
+    tmp_path: Path, enable_setting: str, monkeypatch: pytest.MonkeyPatch
+) -> None:
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
 
@@ -93,7 +98,9 @@ def test_build_identifiers(tmp_path, enable_setting, monkeypatch):
         (None, {"CIBW_ALLOW_EMPTY": "1"}),
     ],
 )
-def test_allow_empty(tmp_path, add_args, env_allow_empty):
+def test_allow_empty(
+    tmp_path: Path, add_args: list[str] | None, env_allow_empty: dict[str, str]
+) -> None:
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
 

test/test_abi_variants.py

@@ -1,4 +1,7 @@
 import textwrap
+from pathlib import Path
+
+import pytest
 
 from . import test_projects, utils
 
@@ -31,7 +34,7 @@ limited_api_project = test_projects.new_c_project(
 limited_api_project.files["pyproject.toml"] = pyproject_toml
 
 
-def test_abi3(tmp_path):
+def test_abi3(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     limited_api_project.generate(project_dir)
 
@@ -178,7 +181,7 @@ ctypes_project.files["test/add_test.py"] = textwrap.dedent(
 ctypes_project.files["pyproject.toml"] = pyproject_toml
 
 
-def test_abi_none(tmp_path, capfd):
+def test_abi_none(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     project_dir = tmp_path / "project"
     ctypes_project.generate(project_dir)
 

test/test_android.py

@@ -2,6 +2,8 @@ import os
 import platform
 import re
 import sys
+import typing
+from collections.abc import Callable
 from dataclasses import dataclass
 from pathlib import Path
 from shutil import rmtree, which
@@ -52,8 +54,10 @@ if "ANDROID_HOME" not in os.environ:
 # Many CI services don't support running the Android emulator: see platforms.md.
 supports_emulator = (not ci) or ("GITHUB_ACTIONS" in os.environ and platform.system() == "Linux")
 
+T = typing.TypeVar("T", bound=Callable[..., typing.Any])
 
-def needs_emulator(test):
+
+def needs_emulator(test: T) -> T:
     # All copies of the testbed app run on the same emulator with the same
     # application ID, so these tests must be run serially.
     test = pytest.mark.serial(test)
@@ -85,7 +89,7 @@ cp313_env = {
 }
 
 
-def test_android_home(tmp_path, capfd):
+def test_android_home(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     new_c_project().generate(tmp_path)
     env = os.environ.copy()
     del env["ANDROID_HOME"]
@@ -100,7 +104,7 @@ def test_android_home(tmp_path, capfd):
 # a build, which is marked as serial so it will run before the parallel tests, but isn't
 # marked as needs_emulator so it will run on all CI platforms.
 @pytest.mark.serial
-def test_expected_wheels(tmp_path, spam_env):
+def test_expected_wheels(tmp_path: Path, spam_env: dict[str, str]) -> None:
     # Since this test covers all Python versions, check the cross venv.
     test_module = "_cross_venv_test_android"
     project = new_c_project(setup_py_add=f"import {test_module}")
@@ -119,7 +123,7 @@ def test_expected_wheels(tmp_path, spam_env):
 
 
 @needs_emulator
-def test_frontend_good(tmp_path, build_frontend_env):
+def test_frontend_good(tmp_path: Path, build_frontend_env: dict[str, str]) -> None:
     new_c_project().generate(tmp_path)
     wheels = cibuildwheel_run(
         tmp_path,
@@ -129,7 +133,7 @@ def test_frontend_good(tmp_path, build_frontend_env):
 
 
 @pytest.mark.parametrize("frontend", ["pip"])
-def test_frontend_bad(frontend, tmp_path, capfd):
+def test_frontend_bad(frontend: str, tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     new_c_project().generate(tmp_path)
     with pytest.raises(CalledProcessError):
         cibuildwheel_run(
@@ -140,7 +144,7 @@ def test_frontend_bad(frontend, tmp_path, capfd):
 
 
 @needs_emulator
-def test_archs(tmp_path, capfd):
+def test_archs(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     new_c_project().generate(tmp_path)
 
     # Build all architectures while checking the handling of the `before` commands.
@@ -189,7 +193,7 @@ def test_archs(tmp_path, capfd):
         pytest.fail(f"Unexpected line: {line!r}")
 
 
-def test_build_requires(tmp_path, capfd):
+def test_build_requires(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     # Build-time requirements should be installed for the build platform, not for Android. Prove
     # this by installing some non-pure-Python requirements and using them in setup.py.
     #
@@ -226,13 +230,13 @@ def test_build_requires(tmp_path, capfd):
 
 
 @pytest.fixture
-def spam_env(tmp_path):
+def spam_env(tmp_path: Path) -> dict[str, str]:
     project = new_c_project()
     project.files["test_spam.py"] = dedent(
         """\
         import spam
 
-        def test_spam():
+        def test_spam() -> None:
             assert spam.filter("ham")
             assert not spam.filter("spam")
             print("Spam test passed")
@@ -240,7 +244,7 @@ def spam_env(tmp_path):
     )
     project.files["test_empty.py"] = dedent(
         """\
-        def test_empty():
+        def test_empty() -> None:
             pass
         """
     )
@@ -265,7 +269,13 @@ def spam_env(tmp_path):
         ("pytest test_spam.py", "=== 1 passed in "),
     ],
 )
-def test_test_command_good(command, expected_output, tmp_path, spam_env, capfd):
+def test_test_command_good(
+    command: str,
+    expected_output: str,
+    tmp_path: Path,
+    spam_env: dict[str, str],
+    capfd: pytest.CaptureFixture[str],
+) -> None:
     cibuildwheel_run(tmp_path, add_env={**spam_env, "CIBW_TEST_COMMAND": command})
     stdout, stderr = capfd.readouterr()
     assert expected_output in stdout
@@ -300,7 +310,13 @@ BAD_PLACEHOLDER_ERROR = (
         ("pytest test_ham.py", "not found: test_ham.py"),
     ],
 )
-def test_test_command_bad(command, expected_output, tmp_path, spam_env, capfd):
+def test_test_command_bad(
+    command: str,
+    expected_output: str,
+    tmp_path: Path,
+    spam_env: dict[str, str],
+    capfd: pytest.CaptureFixture[str],
+) -> None:
     with pytest.raises(CalledProcessError):
         cibuildwheel_run(tmp_path, add_env={**spam_env, "CIBW_TEST_COMMAND": command})
     assert expected_output in capfd.readouterr().err
@@ -314,7 +330,9 @@ def test_test_command_bad(command, expected_output, tmp_path, spam_env, capfd):
         ("-E", 1),
     ],
 )
-def test_test_command_python_options(options, expected, tmp_path, capfd):
+def test_test_command_python_options(
+    options: str, expected: int, tmp_path: Path, capfd: pytest.CaptureFixture[str]
+) -> None:
     project = new_c_project()
     project.generate(tmp_path)
 
@@ -330,7 +348,9 @@ def test_test_command_python_options(options, expected, tmp_path, capfd):
 
 
 @needs_emulator
-def test_package_subdir(tmp_path, spam_env, capfd):
+def test_package_subdir(
+    tmp_path: Path, spam_env: dict[str, str], capfd: pytest.CaptureFixture[str]
+) -> None:
     spam_paths = list(tmp_path.iterdir())
     package_dir = tmp_path / "package"
     package_dir.mkdir()
@@ -345,7 +365,7 @@ def test_package_subdir(tmp_path, spam_env, capfd):
 
 
 @needs_emulator
-def test_no_test_sources(tmp_path, capfd):
+def test_no_test_sources(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     new_c_project().generate(tmp_path)
     with pytest.raises(CalledProcessError):
         cibuildwheel_run(
@@ -359,17 +379,17 @@ def test_no_test_sources(tmp_path, capfd):
 
 
 @needs_emulator
-def test_environment_markers(tmp_path):
+def test_environment_markers(tmp_path: Path) -> None:
     project = new_c_project()
     test_filename = "test_environment_markers.py"
     project.files[test_filename] = dedent(
         """\
         import pytest
 
-        def test_android():
+        def test_android() -> None:
             import certifi
 
-        def test_not_android():
+        def test_not_android() -> None:
             try:
                 import platformdirs
             except ImportError:
@@ -392,7 +412,7 @@ def test_environment_markers(tmp_path):
 
 
 @needs_emulator
-def test_verbosity(tmp_path, capfd):
+def test_verbosity(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     new_c_project().generate(tmp_path)
     test_env = {
         **cp313_env,
@@ -418,7 +438,7 @@ def test_verbosity(tmp_path, capfd):
 
 
 @needs_emulator
-def test_api_level(tmp_path, capfd):
+def test_api_level(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     project = new_c_project()
     project.files["pyproject.toml"] = dedent(
         """\
@@ -450,7 +470,7 @@ def test_api_level(tmp_path, capfd):
 
 
 @needs_emulator
-def test_libcxx(tmp_path, capfd):
+def test_libcxx(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     project_dir = tmp_path / "project"
     output_dir = tmp_path / "output"
 
@@ -499,7 +519,7 @@ def test_libcxx(tmp_path, capfd):
 
 
 @needs_emulator
-def test_setuptools_rust(tmp_path, capfd):
+def test_setuptools_rust(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """
     Test Android cross-compilation using the setuptools-rust toolchain.
     """
@@ -584,7 +604,7 @@ def test_setuptools_rust(tmp_path, capfd):
 
 
 @needs_emulator
-def test_maturin(tmp_path, capfd):
+def test_maturin(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """
     Test Android cross-compilation using the maturin backend.
     """

test/test_before_all.py

@@ -1,5 +1,6 @@
 import subprocess
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -29,7 +30,7 @@ project_with_before_build_asserts = test_projects.new_c_project(
 )
 
 
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_before_build_asserts.generate(project_dir)
 
@@ -61,7 +62,7 @@ def test(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_failing_command(tmp_path):
+def test_failing_command(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     test_projects.new_c_project().generate(project_dir)
 
@@ -75,7 +76,7 @@ def test_failing_command(tmp_path):
         )
 
 
-def test_cwd(tmp_path):
+def test_cwd(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     test_projects.new_c_project().generate(project_dir)
 

test/test_before_build.py

@@ -1,5 +1,6 @@
 import subprocess
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -36,7 +37,7 @@ project_with_before_build_asserts = test_projects.new_c_project(
 )
 
 
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_before_build_asserts.generate(project_dir)
 
@@ -65,7 +66,7 @@ def test(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_failing_command(tmp_path):
+def test_failing_command(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     test_projects.new_c_project().generate(project_dir)
 
@@ -79,7 +80,7 @@ def test_failing_command(tmp_path):
         )
 
 
-def test_cwd(tmp_path):
+def test_cwd(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     test_projects.new_c_project().generate(project_dir)
 

test/test_before_test.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 from . import test_projects, utils
 
 before_test_project = test_projects.new_c_project()
@@ -11,7 +13,7 @@ PROJECT_DIR = Path(__file__).parent.parent.resolve()
 
 
 class TestBeforeTest(TestCase):
-    def test_version(self):
+    def test_version(self) -> None:
         # assert that the Python version as written to pythonversion_bt.txt in the CIBW_BEFORE_TEST step
         # is the same one as is currently running.
         # because of use symlinks in MacOS run this test is also need
@@ -20,7 +22,7 @@ class TestBeforeTest(TestCase):
         print('sys.version', sys.version)
         assert stored_version == sys.version
 
-    def test_prefix(self):
+    def test_prefix(self) -> None:
         # check that the prefix also was written
         stored_prefix = PROJECT_DIR.joinpath('pythonprefix_bt.txt').read_text()
         print('stored_prefix', stored_prefix)
@@ -32,7 +34,7 @@ class TestBeforeTest(TestCase):
 """
 
 
-def test(tmp_path, build_frontend_env):
+def test(tmp_path: Path, build_frontend_env: dict[str, str]) -> None:
     project_dir = tmp_path / "project"
     before_test_project.generate(project_dir)
     test_project_dir = project_dir / "dependency"

test/test_build_frontend_args.py

@@ -1,4 +1,5 @@
 import subprocess
+from pathlib import Path
 
 import pytest
 
@@ -12,7 +13,9 @@ from . import test_projects, utils
         "build",
     ],
 )
-def test_build_frontend_args(tmp_path, capfd, frontend_name):
+def test_build_frontend_args(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str], frontend_name: str
+) -> None:
     project = test_projects.new_c_project()
     project_dir = tmp_path / "project"
     project.generate(project_dir)

test/test_build_skip.py

@@ -1,4 +1,5 @@
 import textwrap
+from pathlib import Path
 
 from . import test_projects, utils
 
@@ -15,7 +16,7 @@ project_with_skip_asserts = test_projects.new_c_project(
 )
 
 
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_skip_asserts.generate(project_dir)
 

test/test_container_engine.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 import pytest
 
 from . import test_projects, utils
@@ -5,7 +7,9 @@ from . import test_projects, utils
 basic_project = test_projects.new_c_project()
 
 
-def test_podman(tmp_path, capfd, request):
+def test_podman(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str], request: pytest.FixtureRequest
+) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the test is only relevant to the linux build")
 
@@ -35,7 +39,7 @@ def test_podman(tmp_path, capfd, request):
     assert "test log statement from before-all" in captured.out
 
 
-def test_create_args(tmp_path, capfd):
+def test_create_args(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the test is only relevant to the linux build")
 

test/test_container_images.py

@@ -1,5 +1,6 @@
 import platform
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -22,7 +23,7 @@ dockcross_only_project = test_projects.new_c_project(
 
 
 @pytest.mark.usefixtures("docker_cleanup")
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the test is only relevant to the linux build")
     if platform.machine() not in ["x86_64", "i686"]:

test/test_cpp_standards.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 import jinja2
 
 from . import utils
@@ -52,7 +54,7 @@ cpp_test_project.files["setup.py"] = jinja2.Template(setup_py_template)
 cpp_test_project.files["spam.cpp"] = jinja2.Template(spam_cpp_template)
 
 
-def test_cpp11(tmp_path):
+def test_cpp11(tmp_path: Path) -> None:
     # This test checks that the C++11 standard is supported
     project_dir = tmp_path / "project"
     cpp11_project = cpp_test_project.copy()
@@ -68,7 +70,7 @@ def test_cpp11(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_cpp14(tmp_path):
+def test_cpp14(tmp_path: Path) -> None:
     # This test checks that the C++14 standard is supported
     project_dir = tmp_path / "project"
     cpp14_project = cpp_test_project.copy()
@@ -84,7 +86,7 @@ def test_cpp14(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_cpp17(tmp_path):
+def test_cpp17(tmp_path: Path) -> None:
     # This test checks that the C++17 standard is supported
     project_dir = tmp_path / "project"
     cpp17_project = cpp_test_project.copy()

test/test_custom_repair_wheel.py

@@ -1,6 +1,7 @@
 import subprocess
 import textwrap
 from contextlib import nullcontext as does_not_raise
+from pathlib import Path
 
 import pytest
 
@@ -30,7 +31,7 @@ shutil.copy(wheel, dest)
 """
 
 
-def test(tmp_path, capfd):
+def test(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     # this test checks that a generated wheel name shall be unique in a given cibuildwheel run
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
@@ -68,7 +69,7 @@ def test(tmp_path, capfd):
     ],
     ids=["no-placeholder", "package-placeholder", "project-placeholder"],
 )
-def test_repair_wheel_command_structure(tmp_path, repair_command):
+def test_repair_wheel_command_structure(tmp_path: Path, repair_command: str) -> None:
     project_dir = tmp_path / "project"
     project = test_projects.new_c_project()
     project.files["repair.py"] = textwrap.dedent("""

test/test_dependency_versions.py

@@ -36,7 +36,9 @@ for name, expected_version in expected_versions.items():
 """
 
 
-def test_check_versions_script(tmp_path, build_frontend_env_nouv, capfd):
+def test_check_versions_script(
+    tmp_path: Path, build_frontend_env_nouv: dict[str, str], capfd: pytest.CaptureFixture[str]
+) -> None:
     if utils.get_platform() == "linux":
         pytest.skip("we don't test dependency versions on linux, refer to other tests")
 
@@ -76,7 +78,9 @@ def get_versions_from_constraint_file(constraint_file: Path) -> dict[str, str]:
 
 
 @pytest.mark.parametrize("python_version", ["3.8", "3.12"])
-def test_pinned_versions(tmp_path, python_version, build_frontend_env_nouv):
+def test_pinned_versions(
+    tmp_path: Path, python_version: str, build_frontend_env_nouv: dict[str, str]
+) -> None:
     if utils.get_platform() == "linux":
         pytest.skip("linux doesn't pin individual tool versions, it pins manylinux images instead")
     if python_version != "3.12" and utils.get_platform() == "pyodide":
@@ -127,7 +131,9 @@ def test_pinned_versions(tmp_path, python_version, build_frontend_env_nouv):
 
 
 @pytest.mark.parametrize("method", ["inline", "file"])
-def test_dependency_constraints(method, tmp_path, build_frontend_env_nouv):
+def test_dependency_constraints(
+    method: str, tmp_path: Path, build_frontend_env_nouv: dict[str, str]
+) -> None:
     if utils.get_platform() == "linux":
         pytest.skip("linux doesn't pin individual tool versions, it pins manylinux images instead")
 

test/test_emulation.py

@@ -1,5 +1,6 @@
 import itertools
 import subprocess
+from pathlib import Path
 
 import pytest
 
@@ -10,13 +11,13 @@ project_with_a_test = test_projects.new_c_project()
 project_with_a_test.files["test/spam_test.py"] = r"""
 import spam
 
-def test_spam():
+def test_spam() -> None:
     assert spam.filter("spam") == 0
     assert spam.filter("ham") != 0
 """
 
 
-def test(tmp_path, request):
+def test(tmp_path: Path, request: pytest.FixtureRequest) -> None:
     archs = request.config.getoption("--run-emulation")
     if archs is None:
         pytest.skip("needs --run-emulation option to run")
@@ -45,7 +46,7 @@ def test(tmp_path, request):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_setting_arch_on_other_platforms(tmp_path, capfd):
+def test_setting_arch_on_other_platforms(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     if utils.get_platform() == "linux":
         pytest.skip("this test checks the behaviour on platforms other than linux")
 

test/test_environment.py

@@ -2,6 +2,7 @@ import os
 import subprocess
 import sys
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -33,7 +34,7 @@ project_with_environment_asserts = test_projects.new_c_project(
 )
 
 
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     python_echo = f"'{sys.executable}' -c \"import sys; print(*sys.argv[1:])\""
     project_dir = tmp_path / "project"
     project_with_environment_asserts.generate(project_dir)
@@ -55,7 +56,7 @@ def test(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_overridden_path(tmp_path, capfd):
+def test_overridden_path(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     project_dir = tmp_path / "project"
     output_dir = tmp_path / "output"
 
@@ -108,7 +109,7 @@ def test_overridden_path(tmp_path, capfd):
         ),
     ],
 )
-def test_overridden_pip_constraint(tmp_path, build_frontend):
+def test_overridden_pip_constraint(tmp_path: Path, build_frontend: str) -> None:
     """
     Verify that users can use PIP_CONSTRAINT to specify a specific version of
     a build-system.requires dependency, by asserting the version of pytz in the

test/test_from_sdist.py

@@ -6,6 +6,8 @@ from collections.abc import Mapping
 from pathlib import Path
 from tempfile import TemporaryDirectory
 
+import pytest
+
 from test.test_projects.base import TestProject
 
 from . import test_projects, utils
@@ -59,7 +61,7 @@ def cibuildwheel_from_sdist_run(
 # tests
 
 
-def test_simple(tmp_path):
+def test_simple(tmp_path: Path) -> None:
     basic_project = test_projects.new_c_project()
 
     # make an sdist of the project
@@ -87,7 +89,7 @@ def test_simple(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_external_config_file_argument(tmp_path, capfd):
+def test_external_config_file_argument(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     basic_project = test_projects.new_c_project()
 
     # make an sdist of the project
@@ -118,7 +120,7 @@ def test_external_config_file_argument(tmp_path, capfd):
     assert "test log statement from before-all" in captured.out
 
 
-def test_config_in_pyproject_toml(tmp_path, capfd):
+def test_config_in_pyproject_toml(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     # make a project with a pyproject.toml
     project = test_projects.new_c_project()
     project.files["pyproject.toml"] = textwrap.dedent(
@@ -145,7 +147,7 @@ def test_config_in_pyproject_toml(tmp_path, capfd):
     assert "test log statement from before-build 8419" in captured.out
 
 
-def test_internal_config_file_argument(tmp_path, capfd):
+def test_internal_config_file_argument(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     # make a project with a config file inside
     project = test_projects.new_c_project(
         setup_cfg_add="include_package_data = True",

test/test_ios.py

@@ -3,6 +3,7 @@ import platform
 import shutil
 import subprocess
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -22,7 +23,7 @@ import platform
 from unittest import TestCase
 
 class TestPlatform(TestCase):
-    def test_platform(self):
+    def test_platform(self) -> None:
         self.assertEqual(platform.machine(), "{platform.machine()}")
 
 """
@@ -59,7 +60,12 @@ def skip_if_ios_testing_not_supported() -> None:
         {"CIBW_PLATFORM": "ios", "CIBW_BUILD_FRONTEND": "build"},
     ],
 )
-def test_ios_platforms(tmp_path, build_config, monkeypatch, capfd):
+def test_ios_platforms(
+    tmp_path: Path,
+    build_config: dict[str, str],
+    monkeypatch: pytest.MonkeyPatch,
+    capfd: pytest.CaptureFixture[str],
+) -> None:
     skip_if_ios_testing_not_supported()
 
     # Create a temporary "bin" directory, symlink a tool that we know eixsts
@@ -67,7 +73,9 @@ def test_ios_platforms(tmp_path, build_config, monkeypatch, capfd):
     # and add the temp bin directory to the PATH.
     tools_dir = tmp_path / "bin"
     tools_dir.mkdir()
-    tools_dir.joinpath("does-exist").symlink_to(shutil.which("true"))
+    true_app = shutil.which("true")
+    assert true_app is not None
+    tools_dir.joinpath("does-exist").symlink_to(true_app)
 
     monkeypatch.setenv("PATH", str(tools_dir), prepend=os.pathsep)
 
@@ -110,7 +118,7 @@ def test_ios_platforms(tmp_path, build_config, monkeypatch, capfd):
 
 
 @pytest.mark.serial
-def test_no_test_sources(tmp_path, capfd):
+def test_no_test_sources(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """Build will provide a helpful error if pytest is run and test-sources is not defined."""
     skip_if_ios_testing_not_supported()
 
@@ -138,7 +146,7 @@ def test_no_test_sources(tmp_path, capfd):
     )
 
 
-def test_ios_testing_with_placeholder(tmp_path, capfd):
+def test_ios_testing_with_placeholder(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """
     Tests with the {project} placeholder are not supported on iOS, because the test command
     is run in the simulator.
@@ -168,7 +176,7 @@ def test_ios_testing_with_placeholder(tmp_path, capfd):
 
 @pytest.mark.serial
 @pytest.mark.flaky(reruns=2)
-def test_ios_test_command_short_circuit(tmp_path, capfd):
+def test_ios_test_command_short_circuit(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     skip_if_ios_testing_not_supported()
 
     project_dir = tmp_path / "project"
@@ -196,7 +204,7 @@ def test_ios_test_command_short_circuit(tmp_path, capfd):
     assert "Zen of Python" not in captured.out + captured.err
 
 
-def test_missing_xbuild_tool(tmp_path, capfd):
+def test_missing_xbuild_tool(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """Build will fail if xbuild-tools references a non-existent tool."""
     skip_if_ios_testing_not_supported()
 
@@ -220,7 +228,7 @@ def test_missing_xbuild_tool(tmp_path, capfd):
     assert "Could not find a 'does-not-exist' executable on the path." in captured.err
 
 
-def test_no_xbuild_tool_definition(tmp_path, capfd):
+def test_no_xbuild_tool_definition(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """Build will succeed with a warning if there is no xbuild-tools definition."""
     skip_if_ios_testing_not_supported()
 
@@ -254,7 +262,7 @@ def test_no_xbuild_tool_definition(tmp_path, capfd):
     assert "Your project configuration does not define any cross-build tools." in captured.err
 
 
-def test_empty_xbuild_tool_definition(tmp_path, capfd):
+def test_empty_xbuild_tool_definition(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """Build will succeed with no warning if there is an empty xbuild-tools definition."""
     skip_if_ios_testing_not_supported()
 
@@ -286,7 +294,9 @@ def test_empty_xbuild_tool_definition(tmp_path, capfd):
 
 
 @pytest.mark.serial
-def test_ios_test_command_without_python_dash_m(tmp_path, capfd):
+def test_ios_test_command_without_python_dash_m(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str]
+) -> None:
     """pytest should be able to run without python -m, but it should warn."""
     skip_if_ios_testing_not_supported()
 
@@ -296,7 +306,7 @@ def test_ios_test_command_without_python_dash_m(tmp_path, capfd):
     project.files["tests/__init__.py"] = ""
     project.files["tests/test_spam.py"] = textwrap.dedent("""
         import spam
-        def test_spam():
+        def test_spam() -> None:
             assert spam.filter("spam") == 0
             assert spam.filter("ham") != 0
     """)
@@ -324,7 +334,7 @@ def test_ios_test_command_without_python_dash_m(tmp_path, capfd):
     assert "iOS tests configured with a test command which doesn't start with 'python -m'" in err
 
 
-def test_ios_test_command_invalid(tmp_path, capfd):
+def test_ios_test_command_invalid(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     """Test command should raise an error if it's clearly invalid."""
     skip_if_ios_testing_not_supported()
 
@@ -347,7 +357,7 @@ def test_ios_test_command_invalid(tmp_path, capfd):
     assert "iOS tests configured with a test command which doesn't start with 'python -m'" in err
 
 
-def test_repair_step(tmp_path):
+def test_repair_step(tmp_path: Path) -> None:
     """Build will succeed & the custom repair step is called."""
     skip_if_ios_testing_not_supported()
 

test/test_linux_python.py

@@ -1,12 +1,13 @@
 import platform
 import subprocess
+from pathlib import Path
 
 import pytest
 
 from . import test_projects, utils
 
 
-def test_python_exist(tmp_path, capfd):
+def test_python_exist(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the test is only relevant to the linux build")
     machine = platform.machine()

test/test_macos_archs.py

@@ -1,4 +1,5 @@
 import platform
+from pathlib import Path
 
 import pytest
 
@@ -19,7 +20,7 @@ ALL_MACOS_WHEELS = {
 DEPLOYMENT_TARGET_TOO_LOW_WARNING = "Bumping MACOSX_DEPLOYMENT_TARGET"
 
 
-def test_cross_compiled_build(tmp_path):
+def test_cross_compiled_build(tmp_path: Path) -> None:
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
     if utils.get_xcode_version() < (12, 2):
@@ -51,7 +52,12 @@ def test_cross_compiled_build(tmp_path):
         },
     ],
 )
-def test_cross_compiled_test(tmp_path, capfd, build_universal2, test_config):
+def test_cross_compiled_test(
+    tmp_path: Path,
+    capfd: pytest.CaptureFixture[str],
+    build_universal2: bool,
+    test_config: dict[str, str],
+) -> None:
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
     if utils.get_xcode_version() < (12, 2):
@@ -110,7 +116,9 @@ def test_cross_compiled_test(tmp_path, capfd, build_universal2, test_config):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_deployment_target_warning_is_firing(tmp_path, capfd):
+def test_deployment_target_warning_is_firing(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str]
+) -> None:
     # force the warning to check that we can detect it if it happens
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
@@ -133,7 +141,9 @@ def test_deployment_target_warning_is_firing(tmp_path, capfd):
 
 
 @pytest.mark.parametrize("skip_arm64_test", [False, True])
-def test_universal2_testing_on_x86_64(tmp_path, capfd, skip_arm64_test):
+def test_universal2_testing_on_x86_64(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str], skip_arm64_test: bool
+) -> None:
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
     if utils.get_xcode_version() < (12, 2):
@@ -172,7 +182,9 @@ def test_universal2_testing_on_x86_64(tmp_path, capfd, skip_arm64_test):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_universal2_testing_on_arm64(build_frontend_env, tmp_path, capfd):
+def test_universal2_testing_on_arm64(
+    build_frontend_env: dict[str, str], tmp_path: Path, capfd: pytest.CaptureFixture[str]
+) -> None:
     # cibuildwheel should test the universal2 wheel on both x86_64 and arm64, when run on arm64
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
@@ -203,7 +215,9 @@ def test_universal2_testing_on_arm64(build_frontend_env, tmp_path, capfd):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_cp38_arm64_testing(tmp_path, capfd, request):
+def test_cp38_arm64_testing(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str], request: pytest.FixtureRequest
+) -> None:
     if utils.get_platform() != "macos":
         pytest.skip("this test is only relevant to macos")
     if utils.get_xcode_version() < (12, 2):
@@ -238,7 +252,9 @@ def test_cp38_arm64_testing(tmp_path, capfd, request):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_cp38_arm64_testing_universal2_installer(tmp_path, capfd, request):
+def test_cp38_arm64_testing_universal2_installer(
+    tmp_path: Path, capfd: pytest.CaptureFixture[str], request: pytest.FixtureRequest
+) -> None:
     if not request.config.getoption("--run-cp38-universal2"):
         pytest.skip("needs --run-cp38-universal2 option to run")
 

test/test_manylinuxXXXX_only.py

@@ -1,5 +1,6 @@
 import platform
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -61,7 +62,7 @@ project_with_manylinux_symbols = test_projects.new_c_project(
     ],
 )
 @pytest.mark.usefixtures("docker_cleanup")
-def test(manylinux_image, tmp_path):
+def test(manylinux_image: str, tmp_path: Path) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the container image test is only relevant to the linux build")
 

test/test_meson_python.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 import packaging.utils
 
 from . import test_projects, utils
@@ -5,7 +7,7 @@ from . import test_projects, utils
 meson_project = test_projects.new_meson_project()
 
 
-def test_meson_python_basic(tmp_path, build_frontend_env):
+def test_meson_python_basic(tmp_path: Path, build_frontend_env: dict[str, str]) -> None:
     """Test that cibuildwheel can build a project with meson-python backend."""
     project_dir = tmp_path / "project"
 

test/test_musllinux_X_Y_only.py

@@ -1,4 +1,5 @@
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -27,7 +28,7 @@ project_with_manylinux_symbols = test_projects.new_c_project(
     ["musllinux_1_2"],
 )
 @pytest.mark.usefixtures("docker_cleanup")
-def test(musllinux_image, tmp_path):
+def test(musllinux_image: str, tmp_path: Path) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("the container image test is only relevant to the linux build")
 

test/test_pep518.py

@@ -1,4 +1,5 @@
 import textwrap
+from pathlib import Path
 
 from . import test_projects, utils
 
@@ -29,7 +30,7 @@ build-backend = "setuptools.build_meta"
 """
 
 
-def test_pep518(tmp_path, build_frontend_env):
+def test_pep518(tmp_path: Path, build_frontend_env: dict[str, str]) -> None:
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)
 

test/test_pure_wheel.py

@@ -1,4 +1,5 @@
 import subprocess
+from pathlib import Path
 
 import pytest
 
@@ -23,7 +24,7 @@ def a_function():
 """
 
 
-def test(tmp_path, capfd):
+def test(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     # this test checks that if a pure wheel is generated, the build should
     # fail.
     project_dir = tmp_path / "project"

test/test_pyodide.py

@@ -3,6 +3,7 @@ import os
 import subprocess
 import sys
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -48,7 +49,7 @@ if __name__ == "__main__":
 
 
 @pytest.mark.parametrize("use_pyproject_toml", [True, False])
-def test_pyodide_build(tmp_path, use_pyproject_toml):
+def test_pyodide_build(tmp_path: Path, use_pyproject_toml: bool) -> None:
     if sys.platform == "win32":
         pytest.skip("pyodide-build doesn't work correctly on Windows")
 
@@ -88,7 +89,7 @@ def test_pyodide_build(tmp_path, use_pyproject_toml):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_pyodide_version_incompatible(tmp_path, capfd):
+def test_pyodide_version_incompatible(tmp_path: Path, capfd: pytest.CaptureFixture[str]) -> None:
     if sys.platform == "win32":
         pytest.skip("pyodide-build doesn't work correctly on Windows")
 
@@ -110,19 +111,19 @@ def test_pyodide_version_incompatible(tmp_path, capfd):
 
 
 @pytest.mark.parametrize("expect_failure", [True, False])
-def test_pyodide_build_and_test(tmp_path, expect_failure):
+def test_pyodide_build_and_test(tmp_path: Path, expect_failure: bool) -> None:
     if sys.platform == "win32":
         pytest.skip("pyodide-build doesn't work correctly on Windows")
 
     if expect_failure:
         basic_project.files["test/spam_test.py"] = textwrap.dedent(r"""
-            def test_filter():
+            def test_filter() -> None:
                 assert 0 == 1
         """)
     else:
         basic_project.files["test/spam_test.py"] = textwrap.dedent(r"""
             import spam
-            def test_filter():
+            def test_filter() -> None:
                 assert spam.filter("spam") == 0
         """)
     basic_project.generate(tmp_path)
@@ -149,7 +150,7 @@ def test_pyodide_build_and_test(tmp_path, expect_failure):
         assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_pyodide_repair_wheel(tmp_path):
+def test_pyodide_repair_wheel(tmp_path: Path) -> None:
     if sys.platform == "win32":
         pytest.skip("pyodide-build doesn't work correctly on Windows")
 

test/test_ssl.py

@@ -1,4 +1,5 @@
 import textwrap
+from pathlib import Path
 
 import pytest
 
@@ -32,7 +33,7 @@ project_with_ssl_tests = test_projects.new_c_project(
 
 
 @pytest.mark.flaky(reruns=2)
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     # this test checks that SSL is working in the build environment using
     # some checks in setup.py.
     project_dir = tmp_path / "project"

test/test_subdir_package.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 
 import jinja2
+import pytest
 
 from . import utils
 from .test_projects import TestProject
@@ -31,7 +32,7 @@ print('before_build.py executed!')
 """
 
 
-def test(capfd, tmp_path):
+def test(capfd: pytest.CaptureFixture[str], tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     subdir_package_project.generate(project_dir)
 

test/test_testing.py

@@ -43,11 +43,11 @@ def path_contains(parent, child):
 
 
 class TestSpam(TestCase):
-    def test_filter(self):
+    def test_filter(self) -> None:
         self.assertEqual(0, spam.filter("spam"))
         self.assertNotEqual(0, spam.filter("ham"))
 
-    def test_virtualenv(self):
+    def test_virtualenv(self) -> None:
         # sys.prefix is different from sys.base_prefix when running a virtualenv
         # See https://docs.python.org/3/library/venv.html, which virtualenv seems
         # to honor in recent releases
@@ -58,7 +58,7 @@ class TestSpam(TestCase):
         self.assertTrue(path_contains(sys.prefix, spam.__file__))
         self.assertIn("VIRTUAL_ENV", os.environ)
 
-    def test_uname(self):
+    def test_uname(self) -> None:
         if platform.system() == "Windows":
             return
         # if we're running in 32-bit Python, check that the machine is i686.
@@ -69,7 +69,7 @@ class TestSpam(TestCase):
 '''
 
 
-def test(tmp_path):
+def test(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_a_test.generate(project_dir)
 
@@ -90,7 +90,7 @@ def test(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_extras_require(tmp_path):
+def test_extras_require(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_a_test.generate(project_dir)
 
@@ -112,7 +112,7 @@ def test_extras_require(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_dependency_groups(tmp_path):
+def test_dependency_groups(tmp_path: Path) -> None:
     group_project = project_with_a_test.copy()
     group_project.files["pyproject.toml"] = inspect.cleandoc("""
         [build-system]
@@ -149,12 +149,12 @@ project_with_a_failing_test.files["test/spam_test.py"] = r"""
 from unittest import TestCase
 
 class TestSpam(TestCase):
-    def test_something(self):
+    def test_something(self) -> None:
         self.fail('this test is supposed to fail')
 """
 
 
-def test_failing_test(tmp_path):
+def test_failing_test(tmp_path: Path) -> None:
     """Ensure a failing test causes cibuildwheel to error out and exit"""
     project_dir = tmp_path / "project"
     output_dir = tmp_path / "output"
@@ -215,7 +215,7 @@ def test_bare_pytest_invocation(
     )
 
 
-def test_test_sources(tmp_path):
+def test_test_sources(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     project_with_a_test.generate(project_dir)
 
@@ -235,7 +235,7 @@ def test_test_sources(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_test_environment(tmp_path):
+def test_test_environment(tmp_path: Path) -> None:
     project_dir = tmp_path / "project"
     test_projects.new_c_project().generate(project_dir)
 

test/test_troubleshooting.py

@@ -1,4 +1,5 @@
 import subprocess
+from pathlib import Path
 
 import pytest
 
@@ -9,7 +10,12 @@ SO_FILE_WARNING = "NOTE: Shared object (.so) files found in this project."
 
 
 @pytest.mark.parametrize("project_contains_so_files", [False, True])
-def test_failed_build_with_so_files(tmp_path, capfd, build_frontend_env, project_contains_so_files):
+def test_failed_build_with_so_files(
+    tmp_path: Path,
+    capfd: pytest.CaptureFixture[str],
+    build_frontend_env: dict[str, str],
+    project_contains_so_files: bool,
+) -> None:
     project = TestProject()
     project.files["setup.py"] = "raise Exception('this build will fail')\n"
     if project_contains_so_files:
@@ -35,7 +41,11 @@ def test_failed_build_with_so_files(tmp_path, capfd, build_frontend_env, project
 
 
 @pytest.mark.parametrize("project_contains_so_files", [False, True])
-def test_failed_repair_with_so_files(tmp_path, capfd, project_contains_so_files):
+def test_failed_repair_with_so_files(
+    tmp_path: Path,
+    capfd: pytest.CaptureFixture[str],
+    project_contains_so_files: bool,
+) -> None:
     if utils.get_platform() != "linux":
         pytest.skip("this test is only relevant to the linux build")
 

test/test_wheel_tag.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 import pytest
 
 from . import test_projects, utils
@@ -5,7 +7,7 @@ from . import test_projects, utils
 basic_project = test_projects.new_c_project()
 
 
-def test_wheel_tag_is_correct_when_using_macosx_deployment_target(tmp_path):
+def test_wheel_tag_is_correct_when_using_macosx_deployment_target(tmp_path: Path) -> None:
     if utils.get_platform() != "macos":
         pytest.skip("This test is only relevant to MACOSX_DEPLOYMENT_TARGET")
 

test/test_windows.py

@@ -38,7 +38,9 @@ def skip_if_no_msvc(arm64: bool = False) -> None:
 
 
 @pytest.mark.parametrize("use_pyproject_toml", [True, False])
-def test_wheel_tag_is_correct_when_using_windows_cross_compile(tmp_path, use_pyproject_toml):
+def test_wheel_tag_is_correct_when_using_windows_cross_compile(
+    tmp_path: Path, use_pyproject_toml: bool
+) -> None:
     if utils.get_platform() != "windows":
         pytest.skip("This test is only relevant to Windows")
 

test/utils.py

@@ -11,7 +11,7 @@ import sys
 from collections.abc import Generator, Mapping, Sequence
 from pathlib import Path
 from tempfile import TemporaryDirectory
-from typing import Any, Final
+from typing import Final
 
 import pytest
 
@@ -458,7 +458,7 @@ def get_xcode_version() -> tuple[int, int]:
     return (int(version_parts[0]), int(version_parts[1]))
 
 
-def skip_if_pyodide(reason: str) -> Any:
+def skip_if_pyodide(reason: str) -> pytest.MarkDecorator:
     return pytest.mark.skipif(get_platform() == "pyodide", reason=reason)