feature: add support for ABI3 wheels

cibuildwheel/linux.py

@@ -12,6 +12,7 @@ from .typing import OrderedDict, PathOrStr, assert_never
 from .util import (
     BuildSelector,
     NonPlatformWheelError,
+    find_compatible_abi3_wheel,
     get_build_verbosity_extra_flags,
     prepare_command,
     read_python_configs,
@@ -132,6 +133,8 @@ def build_on_docker(
         )
         docker.call(["sh", "-c", before_all_prepared], env=env)
 
+    built_wheels: List[PurePath] = []
+
     for config in platform_configs:
         log.build_start(config.identifier)
         build_options = options.build_options(config.identifier)
@@ -174,6 +177,15 @@ def build_on_docker(
             )
             sys.exit(1)
 
+        abi3_wheel = find_compatible_abi3_wheel(built_wheels, config.identifier)
+        if abi3_wheel:
+            log.step_end()
+            print(
+                f"Found previously built wheel {abi3_wheel.name}, that's compatible with {config.identifier}. Skipping build step..."
+            )
+            repaired_wheels = [abi3_wheel]
+        else:
+
             if build_options.before_build:
                 log.step("Running before_build...")
                 before_build_prepared = prepare_command(
@@ -292,8 +304,12 @@ def build_on_docker(
             docker.call(["rm", "-rf", venv_dir])
 
         # move repaired wheels to output
+        if abi3_wheel is None:
             docker.call(["mkdir", "-p", container_output_dir])
             docker.call(["mv", *repaired_wheels, container_output_dir])
+            built_wheels.extend(
+                container_output_dir / repaired_wheel.name for repaired_wheel in repaired_wheels
+            )
 
         log.build_end()
 

cibuildwheel/macos.py

@@ -23,6 +23,7 @@ from .util import (
     call,
     detect_ci_provider,
     download,
+    find_compatible_abi3_wheel,
     get_build_verbosity_extra_flags,
     get_pip_version,
     install_certifi_script,
@@ -291,6 +292,8 @@ def build(options: Options, tmp_path: Path) -> None:
             )
             shell(before_all_prepared, env=env)
 
+        built_wheels: List[Path] = []
+
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
             log.build_start(config.identifier)
@@ -318,6 +321,14 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_options.build_frontend,
             )
 
+            abi3_wheel = find_compatible_abi3_wheel(built_wheels, config.identifier)
+            if abi3_wheel:
+                log.step_end()
+                print(
+                    f"Found previously built wheel {abi3_wheel.name}, that's compatible with {config.identifier}. Skipping build step..."
+                )
+                repaired_wheel = abi3_wheel
+            else:
                 if build_options.before_build:
                     log.step("Running before_build...")
                     before_build_prepared = prepare_command(
@@ -348,9 +359,11 @@ def build(options: Options, tmp_path: Path) -> None:
                     config_setting = " ".join(verbosity_flags)
                     build_env = env.copy()
                     if build_options.dependency_constraints:
-                    constraint_path = build_options.dependency_constraints.get_for_python_version(
+                        constraint_path = (
+                            build_options.dependency_constraints.get_for_python_version(
                                 config.version
                             )
+                        )
                         build_env["PIP_CONSTRAINT"] = constraint_path.as_uri()
                     build_env["VIRTUALENV_PIP"] = get_pip_version(env)
                     call(
@@ -521,7 +534,9 @@ def build(options: Options, tmp_path: Path) -> None:
                     )
 
             # we're all done here; move it to output (overwrite existing)
+            if abi3_wheel is None:
                 shutil.move(str(repaired_wheel), build_options.output_dir)
+                built_wheels.append(build_options.output_dir / repaired_wheel.name)
 
             # clean up
             shutil.rmtree(identifier_tmp_dir)

cibuildwheel/util.py

@@ -13,7 +13,7 @@ import time
 import urllib.request
 from enum import Enum
 from functools import lru_cache
-from pathlib import Path
+from pathlib import Path, PurePath
 from time import sleep
 from typing import (
     Any,
@@ -26,6 +26,7 @@ from typing import (
     Optional,
     Sequence,
     TextIO,
+    TypeVar,
     cast,
     overload,
 )
@@ -41,6 +42,7 @@ else:
 from filelock import FileLock
 from packaging.requirements import InvalidRequirement, Requirement
 from packaging.specifiers import SpecifierSet
+from packaging.utils import parse_wheel_filename
 from packaging.version import Version
 from platformdirs import user_cache_path
 
@@ -51,6 +53,7 @@ __all__ = [
     "MANYLINUX_ARCHS",
     "call",
     "shell",
+    "find_compatible_abi3_wheel",
     "format_safe",
     "prepare_command",
     "get_build_verbosity_extra_flags",
@@ -566,6 +569,42 @@ def virtualenv(
     return env
 
 
+T = TypeVar("T", bound=PurePath)
+
+
+def find_compatible_abi3_wheel(wheels: Sequence[T], identifier: str) -> Optional[T]:
+    """
+    Finds an ABI3 wheel in `wheels` compatible with the Python interpreter
+    specified by `identifier`.
+    """
+
+    interpreter, platform = identifier.split("-")
+    if not interpreter.startswith("cp3"):
+        return None
+    for wheel in wheels:
+        _, _, _, tags = parse_wheel_filename(wheel.name)
+        for tag in tags:
+            if tag.abi != "abi3":
+                continue
+            if not tag.interpreter.startswith("cp3"):
+                continue
+            if int(tag.interpreter[3:]) > int(interpreter[3:]):
+                continue
+            if platform.startswith(("manylinux", "musllinux", "macosx")):
+                # Linux, macOS
+                os_, arch = platform.split("_", 1)
+                if not tag.platform.startswith(os_):
+                    continue
+                if not tag.platform.endswith("_" + arch):
+                    continue
+            else:
+                # Windows
+                if not tag.platform == platform:
+                    continue
+            return wheel
+    return None
+
+
 if sys.version_info >= (3, 8):
     from functools import cached_property
 else:

cibuildwheel/windows.py

@@ -22,6 +22,7 @@ from .util import (
     NonPlatformWheelError,
     call,
     download,
+    find_compatible_abi3_wheel,
     get_build_verbosity_extra_flags,
     get_pip_version,
     prepare_command,
@@ -249,6 +250,8 @@ def build(options: Options, tmp_path: Path) -> None:
             )
             shell(before_all_prepared, env=env)
 
+        built_wheels: List[Path] = []
+
         for config in python_configurations:
             build_options = options.build_options(config.identifier)
             log.build_start(config.identifier)
@@ -274,6 +277,14 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_options.build_frontend,
             )
 
+            abi3_wheel = find_compatible_abi3_wheel(built_wheels, config.identifier)
+            if abi3_wheel:
+                log.step_end()
+                print(
+                    f"Found previously built wheel {abi3_wheel.name}, that's compatible with {config.identifier}. Skipping build step..."
+                )
+                repaired_wheel = abi3_wheel
+            else:
                 # run the before_build command
                 if build_options.before_build:
                     log.step("Running before_build...")
@@ -305,9 +316,11 @@ def build(options: Options, tmp_path: Path) -> None:
                     config_setting = " ".join(verbosity_flags)
                     build_env = env.copy()
                     if build_options.dependency_constraints:
-                    constraints_path = build_options.dependency_constraints.get_for_python_version(
+                        constraints_path = (
+                            build_options.dependency_constraints.get_for_python_version(
                                 config.version
                             )
+                        )
                         # Bug in pip <= 21.1.3 - we can't have a space in the
                         # constraints file, and pip doesn't support drive letters
                         # in uhi.  After probably pip 21.2, we can use uri. For
@@ -405,7 +418,9 @@ def build(options: Options, tmp_path: Path) -> None:
                 shell(test_command_prepared, cwd="c:\\", env=virtualenv_env)
 
             # we're all done here; move it to output (remove if already exists)
+            if abi3_wheel is None:
                 shutil.move(str(repaired_wheel), build_options.output_dir)
+                built_wheels.append(build_options.output_dir / repaired_wheel.name)
 
             # clean up
             # (we ignore errors because occasionally Windows fails to unlink a file and we

setup.cfg

@@ -35,7 +35,7 @@ install_requires =
     bracex
     certifi
     filelock
-    packaging
+    packaging>=20.9
     platformdirs
     dataclasses;python_version < '3.7'
     tomli;python_version < '3.11'

test/test_limited_api.py

@@ -0,0 +1,50 @@
+import textwrap
+
+from . import test_projects, utils
+
+limited_api_project = test_projects.new_c_project(
+    setup_py_add=textwrap.dedent(
+        r"""
+        cmdclass = {}
+        extension_kwargs = {}
+        if sys.version_info[:2] >= (3, 8):
+            from wheel.bdist_wheel import bdist_wheel as _bdist_wheel
+
+            class bdist_wheel_abi3(_bdist_wheel):
+                def finalize_options(self):
+                    _bdist_wheel.finalize_options(self)
+                    self.root_is_pure = False
+
+                def get_tag(self):
+                    python, abi, plat = _bdist_wheel.get_tag(self)
+                    return python, "abi3", plat
+
+            cmdclass["bdist_wheel"] = bdist_wheel_abi3
+            extension_kwargs["define_macros"] = [("Py_LIMITED_API", "0x03080000")]
+            extension_kwargs["py_limited_api"] = True
+    """
+    ),
+    setup_py_extension_args_add="**extension_kwargs",
+    setup_py_setup_args_add="cmdclass=cmdclass",
+)
+
+
+def test(tmp_path):
+    project_dir = tmp_path / "project"
+    limited_api_project.generate(project_dir)
+
+    # build the wheels
+    actual_wheels = utils.cibuildwheel_run(
+        project_dir,
+        add_env={
+            "CIBW_SKIP": "pp* ",  # PyPy does not have a Py_LIMITED_API equivalent
+        },
+    )
+
+    # check that the expected wheels are produced
+    expected_wheels = [
+        w.replace("cp38-cp38", "cp38-abi3")
+        for w in utils.expected_wheels("spam", "0.1.0")
+        if "-pp" not in w and "-cp39" not in w and "-cp310" not in w
+    ]
+    assert set(actual_wheels) == set(expected_wheels)

test/test_projects/c.py

@@ -54,6 +54,7 @@ setup(
         'spam',
         sources=['spam.c'],
         libraries=libraries,
+        {{ setup_py_extension_args_add | indent(8) }}
     )],
     {{ setup_py_setup_args_add | indent(4) }}
 )
@@ -73,6 +74,7 @@ def new_c_project(
     spam_c_top_level_add="",
     spam_c_function_add="",
     setup_py_add="",
+    setup_py_extension_args_add="",
     setup_py_setup_args_add="",
     setup_cfg_add="",
 ):
@@ -91,6 +93,7 @@ def new_c_project(
             "spam_c_top_level_add": spam_c_top_level_add,
             "spam_c_function_add": spam_c_function_add,
             "setup_py_add": setup_py_add,
+            "setup_py_extension_args_add": setup_py_extension_args_add,
             "setup_py_setup_args_add": setup_py_setup_args_add,
             "setup_cfg_add": setup_cfg_add,
         }