feature: add support for ABI3 wheels

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,
         }