TST: reconcile platform tags with recent packaging on macOS

tests/conftest.py

@@ -4,6 +4,7 @@
 import os
 import os.path
 import pathlib
+import platform
 import re
 import shutil
 import subprocess
@@ -19,13 +20,24 @@
 
 
 def adjust_packaging_platform_tag(platform: str) -> str:
-    # The packaging module generates overly specific platforms tags on
-    # Linux.  The platforms tags on Linux evolved over time.
-    # meson-python uses more relaxed platform tags to maintain
-    # compatibility with old wheel installation tools.  The relaxed
-    # platform tags match the ones generated by the wheel package.
-    # https://packaging.python.org/en/latest/specifications/platform-compatibility-tags/
-    return re.sub(r'^(many|musl)linux(1|2010|2014|_\d+_\d+)_(.*)$', r'linux_\3', platform)
+    if platform.startswith(('manylinux', 'musllinux')):
+        # The packaging module generates overly specific platforms tags on
+        # Linux.  The platforms tags on Linux evolved over time.
+        # meson-python uses more relaxed platform tags to maintain
+        # compatibility with old wheel installation tools.  The relaxed
+        # platform tags match the ones generated by the wheel package.
+        # https://packaging.python.org/en/latest/specifications/platform-compatibility-tags/
+        return re.sub(r'^(many|musl)linux(1|2010|2014|_\d+_\d+)_(.*)$', r'linux_\3', platform)
+    if platform.startwith('macosx'):
+        # Python built with older macOS SDK on macOS 11, reports an
+        # unexising macOS 10.16 version instead of the real version.
+        # The packaging module introduced a workaround in version
+        # 22.0.  Too maintain compatibility with older packaging
+        # releases we don't implement it.  Reconcile this.
+        version = tuple(map(int, platform.mac_ver()[0].split('.'))[:2])
+        if version == (10, 16):
+            return re.sub(r'^macosx_\d+_\d+_(.*)$', r'macosx_10_16_\1', platform)
+    return platform
 
 
 package_dir = pathlib.Path(__file__).parent / 'packages'