Experiment with Python limited API (take 2)

pyproject.toml

@@ -48,7 +48,7 @@ requires = ["setuptools",
             "setuptools_scm",
             "extension-helpers==1.*",
             "numpy>=2.0.0rc1",
-            "cython>=3.0,<3.1"]
+            "cython @ git+https://github.com/da-woods/cython@cpython-library-limited-api"]
 build-backend = 'setuptools.build_meta'
 
 [tool.setuptools]

reproject/adaptive/setup_package.py

@@ -0,0 +1,33 @@
+import os
+
+import numpy as np
+from setuptools import Extension
+
+ADAPTIVE_SUBPKG = os.path.dirname(__file__)
+
+
+def get_extensions():
+    libraries = []
+
+    sources = []
+    sources.append(os.path.join(ADAPTIVE_SUBPKG, "deforest.pyx"))
+
+    include_dirs = [np.get_include()]
+
+    define_macros = []
+
+    define_macros.append(("CYTHON_LIMITED_API", "0x030C0000"))
+    define_macros.append(("Py_LIMITED_API", "0x030C0000"))
+
+    extension = Extension(
+        name="reproject.adaptive.deforest",
+        sources=sources,
+        include_dirs=include_dirs,
+        libraries=libraries,
+        language="c",
+        extra_compile_args=["-O2"],
+        define_macros=define_macros,
+        py_limited_api=True,
+    )
+
+    return [extension]

reproject/spherical_intersect/setup_package.py

@@ -23,7 +23,10 @@
     if int(os.environ.get("DEBUG_OVERLAP_AREA", 0)):
         define_macros = [("DEBUG_OVERLAP_AREA", 1)]
     else:
-        define_macros = None
+        define_macros = []
+
+    define_macros.append(('CYTHON_LIMITED_API', '0x030C0000'))
+    define_macros.append(('Py_LIMITED_API', '0x030C0000'))
 
     extension = Extension(
         name="reproject.spherical_intersect._overlap",
@@ -33,6 +36,7 @@
         language="c",
         extra_compile_args=["-O2"],
         define_macros=define_macros,
+        py_limited_api=True,
     )
 
     return [extension]