Use Cython 3.1 universally (#1514)

Co-authored-by: J. Nick Koston <[email protected]>

Author: lysnikolaou

.github/workflows/ci-cd.yml

@@ -259,9 +259,7 @@ jobs:
       uses: py-actions/py-dependency-install@v4
       with:
         path: >-
-          requirements/test${{
-            matrix.pyver == '3.13t' && '-freethreading' || ''
-          }}.txt
+          requirements/test.txt
     - name: Determine pre-compiled compatible wheel
       env:
         # NOTE: When `pip` is forced to colorize output piped into `jq`,

CHANGES/1514.packaging.rst

@@ -0,0 +1 @@
+Updated to use Cython 3.1 universally across the build path -- by :user:`lysnikolaou`.

packaging/pep517_backend/_backend.py

@@ -4,7 +4,6 @@
 from __future__ import annotations
 
 import os
-import sysconfig
 from collections.abc import Iterator
 from contextlib import contextmanager, nullcontext, suppress
 from functools import partial
@@ -376,10 +375,8 @@ def get_requires_for_build_wheel(
 
     if is_pure_python_build:
         c_ext_build_deps = []
-    elif sysconfig.get_config_var('Py_GIL_DISABLED'):
-        c_ext_build_deps = ['Cython ~= 3.1.0a1']
     else:
-        c_ext_build_deps = ['Cython >= 3.0.12']
+        c_ext_build_deps = ['Cython >= 3.1.2']
 
     return _setuptools_get_requires_for_build_wheel(
         config_settings=config_settings,

pyproject.toml

@@ -91,12 +91,3 @@ pure-python = "false"
 
 [tool.cibuildwheel.windows]
 before-test = []  # Windows cmd has different syntax and pip chooses wheels
-
-# TODO: Remove this when there's a Cython 3.1 final release
-# Remove PIP_CONSTRAINT from the environment
-[[tool.cibuildwheel.overrides]]
-select = "cp313t-*"
-
-test-requires = "-r requirements/test-freethreading.txt"
-inherit.environment = "append"
-environment = {PIP_CONSTRAINT = "requirements/cython-freethreading.txt"}

requirements/cython-freethreading.txt

@@ -1 +1 @@
-cython==3.0.12
+cython==3.1.2

requirements/cython.txt

@@ -1,2 +1,9 @@
 -r cython.txt
--r test-pure.txt
+covdefaults
+hypothesis>=6.0
+idna==3.10
+multidict==6.4.4
+propcache==0.3.1
+pytest==8.4.0
+pytest-cov>=2.3.1
+pytest-xdist