Python: Add 'limited_api' kwarg to extension_module

This commit adds a new keyword arg to extension_module() that enables
a user to target the Python Limited API, declaring the version of the
limited API that they wish to target.

Two new unittests have been added to test this functionality.

1 files changed, 15 insertions, 0 deletions

diff --git a/mesonbuild/scripts/python_info.py b/mesonbuild/scripts/python_info.py
index 9c3a0791a..0f7787c3f 100755
--- a/mesonbuild/scripts/python_info.py
+++ b/mesonbuild/scripts/python_info.py
@@ -65,6 +65,20 @@ elif sys.version_info < (3, 8, 7):
 else:
     suffix = variables.get('EXT_SUFFIX')
 
+limited_api_suffix = None
+if sys.version_info >= (3, 2):
+    try:
+        from importlib.machinery import EXTENSION_SUFFIXES
+        limited_api_suffix = EXTENSION_SUFFIXES[1]
+    except Exception:
+        pass
+
+# pypy supports modules targetting the limited api but
+# does not use a special suffix to distinguish them:
+# https://doc.pypy.org/en/latest/cpython_differences.html#permitted-abi-tags-in-extensions
+if '__pypy__' in sys.builtin_module_names:
+    limited_api_suffix = suffix
+
 print(json.dumps({
   'variables': variables,
   'paths': paths,
@@ -76,4 +90,5 @@ print(json.dumps({
   'is_venv': sys.prefix != variables['base_prefix'],
   'link_libpython': links_against_libpython(),
   'suffix': suffix,
+  'limited_api_suffix': limited_api_suffix,
 }))