Build Python 3.13 wheels (#461)

.github/workflows/publish.yaml

@@ -59,6 +59,7 @@ jobs:
           CIBW_ARCHS_LINUX: auto aarch64
           CIBW_ARCHS_MACOS: auto universal2
           CIBW_BUILD_FRONTEND: build
+          CIBW_FREE_THREADED_SUPPORT: 1
       - uses: actions/upload-artifact@50769540e7f4bd5e21e526ee35c689e35e0d6874 # v4.4.0
         with:
           name: build-wheels-${{ matrix.os }}

.github/workflows/tests.yaml

@@ -22,6 +22,7 @@ jobs:
       matrix:
         include:
           - {python: '3.13'}
+          - {name: 'Free-threaded', python: '3.13', free-threaded: true}
           - {python: '3.12'}
           - {name: Windows, python: '3.12', os: windows-latest}
           - {name: Mac, python: '3.12', os: macos-latest}
@@ -32,13 +33,21 @@ jobs:
     steps:
       - uses: actions/checkout@d632683dd7b4114ad314bca15554477dd762a938 # v4.2.0
       - uses: actions/setup-python@f677139bbe7f9c59b41e40162b753c062f5d49a3 # v5.2.0
+        if: ${{ !matrix.free-threaded }}
         with:
           python-version: ${{ matrix.python }}
           allow-prereleases: true
           cache: pip
           cache-dependency-path: requirements*/*.txt
+      - uses: deadsnakes/action@e640ac8743173a67cca4d7d77cd837e514bf98e8 # v3.2.0
+        if: ${{ matrix.free-threaded }}
+        with:
+          python-version: ${{ matrix.python }}
+          nogil: true
       - run: pip install tox
-      - run: tox run -e ${{ matrix.tox || format('py{0}', matrix.python) }}
+      - env:
+          PYTHON_GIL: ${{ matrix.free-threaded && '0' || '1' }}
+        run: tox run -e ${{ matrix.tox || format('py{0}', matrix.python) }}
   typing:
     runs-on: ubuntu-latest
     steps:

CHANGES.rst

@@ -3,6 +3,7 @@ Version 3.0.0
 
 Unreleased
 
+-   Support Python 3.13 and its experimental free-threaded build. :pr:`461`
 -   Drop support for Python 3.7 and 3.8.
 -   Use modern packaging metadata with ``pyproject.toml`` instead of ``setup.cfg``.
     :pr:`348`

src/markupsafe/_speedups.c

@@ -190,5 +190,15 @@ static struct PyModuleDef module_definition = {
 PyMODINIT_FUNC
 PyInit__speedups(void)
 {
-	return PyModule_Create(&module_definition);
+	PyObject *m = PyModule_Create(&module_definition);
+
+	if (m == NULL) {
+		return NULL;
+	}
+
+	#ifdef Py_GIL_DISABLED
+	PyUnstable_Module_SetGIL(m, Py_MOD_GIL_NOT_USED);
+	#endif
+
+	return m;
 }

tests/conftest.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import sys
 import typing as t
 from types import ModuleType
 
@@ -14,6 +15,14 @@
     _speedups = None  # type: ignore
 
 
+def pytest_report_header() -> list[str]:
+    """Return a list of strings to be displayed in the header of the report."""
+    if sys.version_info >= (3, 13):
+        return [f"Free-threaded: {not sys._is_gil_enabled()}"]
+
+    return []
+
+
 @pytest.fixture(
     scope="session",
     autouse=True,

tox.ini

@@ -9,6 +9,7 @@ skip_missing_interpreters = true
 
 [testenv]
 package = wheel
+pass_env = PYTHON_GIL
 constrain_package_deps = true
 use_frozen_constraints = true
 deps = -r requirements/tests.txt