feat: add musllinux support (PEP 656) (#768)

* feat: add musllinux support (PEP 656)

Add musllinux support (PEP 656) allowing to build wheels for musl libc based distros (e.g. Alpine)

* feat: add musllinux support (PEP 656) doc

* doc: combine `CIBW_MANYLINUX_*_IMAGE` & `CIBW_MUSLLINUX_*_IMAGE` options

* fix: doc to be squashed

* doc: combine manylinux /musllinux in README

* Update docs/options.md

Co-authored-by: Joe Rickerby <joerick@mac.com>

Co-authored-by: Joe Rickerby <joerick@mac.com>

test/test_0_basic.py

@@ -56,4 +56,6 @@ def test_build_identifiers(tmp_path):
     build_identifiers = utils.cibuildwheel_get_build_identifiers(
         project_dir, prerelease_pythons=True
     )
-    assert len(expected_wheels) == len(build_identifiers)
+    assert len(expected_wheels) == len(
+        build_identifiers
+    ), f"{expected_wheels} vs {build_identifiers}"

test/test_docker_images.py

@@ -37,14 +37,14 @@ def test(tmp_path):
         add_env={
             "CIBW_MANYLINUX_X86_64_IMAGE": "dockcross/manylinux2010-x64",
             "CIBW_MANYLINUX_I686_IMAGE": "dockcross/manylinux2010-x86",
-            "CIBW_BUILD": "cp3{6,7,8,9}-*",
+            "CIBW_BUILD": "cp3{6,7,8,9}-manylinux*",
         },
     )
 
     # also check that we got the right wheels built
     expected_wheels = [
         w
-        for w in utils.expected_wheels("spam", "0.1.0")
+        for w in utils.expected_wheels("spam", "0.1.0", musllinux_versions=[])
         if "-cp36-" in w or "-cp37-" in w or "-cp38-" in w or "-cp39-" in w
     ]
     assert set(actual_wheels) == set(expected_wheels)

test/test_manylinuxXXXX_only.py

@@ -57,6 +57,7 @@ def test(manylinux_image, tmp_path):
     # CFLAGS environment variable is necessary to fail on 'malloc_info' (on manylinux1) during compilation/linking,
     # rather than when dynamically loading the Python
     add_env = {
+        "CIBW_BUILD": "*-manylinux*",
         "CIBW_ENVIRONMENT": 'CFLAGS="$CFLAGS -O0 -Werror=implicit-function-declaration"',
         "CIBW_MANYLINUX_X86_64_IMAGE": manylinux_image,
         "CIBW_MANYLINUX_I686_IMAGE": manylinux_image,
@@ -79,7 +80,10 @@ def test(manylinux_image, tmp_path):
         "manylinux2014": ["manylinux_2_17", "manylinux2014"],
     }
     expected_wheels = utils.expected_wheels(
-        "spam", "0.1.0", manylinux_versions=platform_tag_map.get(manylinux_image, [manylinux_image])
+        "spam",
+        "0.1.0",
+        manylinux_versions=platform_tag_map.get(manylinux_image, [manylinux_image]),
+        musllinux_versions=[],
     )
     if manylinux_image in {"manylinux1"}:
         # remove PyPy & CPython 3.10 and above

test/utils.py

@@ -103,6 +103,7 @@ def expected_wheels(
     package_name,
     package_version,
     manylinux_versions=None,
+    musllinux_versions=None,
     macosx_deployment_target="10.9",
     machine_arch=None,
 ):
@@ -123,6 +124,9 @@ def expected_wheels(
         else:
             manylinux_versions = ["manylinux_2_17", "manylinux2014"]
 
+    if musllinux_versions is None:
+        musllinux_versions = ["musllinux_1_1"]
+
     python_abi_tags = ["cp36-cp36m", "cp37-cp37m", "cp38-cp38", "cp39-cp39", "cp310-cp310"]
 
     if machine_arch in ["x86_64", "AMD64", "x86", "aarch64"]:
@@ -155,6 +159,16 @@ def expected_wheels(
                 )
                 for architecture in architectures
             ]
+            if len(musllinux_versions) > 0 and not python_abi_tag.startswith("pp"):
+                platform_tags.extend(
+                    [
+                        ".".join(
+                            f"{musllinux_version}_{architecture}"
+                            for musllinux_version in musllinux_versions
+                        )
+                        for architecture in architectures
+                    ]
+                )
 
         elif platform == "windows":
             if python_abi_tag.startswith("cp"):