fix: support Python 3.14

.github/workflows/ci.yml

@@ -34,6 +34,7 @@ jobs:
         python:
         - '3.8'
         - '3.13'
+        - '3.14'
         - 'pypy-3.10'
         - 'pypy-3.11'
         - 'graalpy-24.2'
@@ -96,6 +97,9 @@ jobs:
               -DCMAKE_CXX_FLAGS="/DPYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE /GR /EHsc"
           - runs-on: 'ubuntu-latest'
             python: 'graalpy-24.1'
+          # Only working one for 3.14.0b1 on Windows
+          - runs-on: windows-2022
+            python: '3.14t'
 
         exclude:
           # The setup-python action currently doesn't have graalpy for windows
@@ -108,6 +112,9 @@ jobs:
           # No NumPy for PyPy 3.10 ARM
           - runs-on: macos-14
             python: 'pypy-3.10'
+          # Beta 1 broken for compiling on GHA (thinks it's free-threaded)
+          - runs-on: windows-2022
+            python: '3.14'
 
 
     name: "🐍 ${{ matrix.python }} • ${{ matrix.runs-on }} • x64 ${{ matrix.args }}"

include/pybind11/eval.h

@@ -133,7 +133,12 @@ object eval_file(str fname, object global = globals(), object local = object())
 
     int closeFile = 1;
     std::string fname_str = (std::string) fname;
-    FILE *f = _Py_fopen_obj(fname.ptr(), "r");
+    FILE *f =
+#    if PY_VERSION_HEX >= 0x030E0000
+        Py_fopen(fname.ptr(), "r");
+#    else
+        _Py_fopen_obj(fname.ptr(), "r");
+#    endif
     if (!f) {
         PyErr_Clear();
         pybind11_fail("File \"" + fname_str + "\" could not be opened!");

pybind11/__main__.py

@@ -2,6 +2,7 @@
 from __future__ import annotations
 
 import argparse
+import functools
 import re
 import sys
 import sysconfig
@@ -49,7 +50,10 @@ def print_includes() -> None:
 
 
 def main() -> None:
-    parser = argparse.ArgumentParser()
+    make_parser = functools.partial(argparse.ArgumentParser, allow_abbrev=False)
+    if sys.version_info >= (3, 14):
+        make_parser = functools.partial(make_parser, color=True, suggest_on_error=True)
+    parser = make_parser()
     parser.add_argument(
         "--version",
         action="version",

pyproject.toml

@@ -22,6 +22,7 @@ classifiers = [
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
     "Programming Language :: Python :: Implementation :: PyPy",
     "Programming Language :: Python :: Implementation :: CPython",
     "Programming Language :: C++",

tests/test_methods_and_attributes.py

@@ -305,6 +305,11 @@ def test_property_rvalue_policy():
 
 # https://foss.heptapod.net/pypy/pypy/-/issues/2447
 @pytest.mark.xfail("env.PYPY")
+@pytest.mark.xfail(
+    sys.version_info == (3, 14, 0, "beta", 1),
+    reason="3.14.0b1 bug: https://github.com/python/cpython/issues/133912",
+    strict=True,
+)
 def test_dynamic_attributes():
     instance = m.DynamicClass()
     assert not hasattr(instance, "foo")

tests/test_multiple_interpreters.py

@@ -15,12 +15,12 @@
 
     sys.path.append(".")
 
-    if sys.version_info >= (3, 14):
+    if sys.version_info >= (3, 15):
         import interpreters
-    elif sys.version_info >= (3, 13):
+    elif sys.version_info >= (3, 14):
         import _interpreters as interpreters
     elif sys.version_info >= (3, 12):
         import _xxsubinterpreters as interpreters
     else:
         pytest.skip("Test requires a the interpreters stdlib module")
 
@@ -87,7 +87,7 @@
     sys.path.append(".")
 
     if sys.version_info >= (3, 14):
         import interpreters
     elif sys.version_info >= (3, 13):
         import _interpreters as interpreters
     elif sys.version_info >= (3, 12):

tests/test_operator_overloading.py

@@ -158,4 +158,4 @@ def test_overriding_eq_reset_hash():
 def test_return_set_of_unhashable():
     with pytest.raises(TypeError) as excinfo:
         m.get_unhashable_HashMe_set()
-    assert str(excinfo.value.__cause__).startswith("unhashable type:")
+    assert "unhashable type" in str(excinfo.value.__cause__)

tests/test_pickling.py

@@ -2,6 +2,7 @@
 
 import pickle
 import re
+import sys
 
 import pytest
 
@@ -62,7 +63,20 @@ def test_roundtrip(cls_name):
 
 
 @pytest.mark.xfail("env.PYPY")
-@pytest.mark.parametrize("cls_name", ["PickleableWithDict", "PickleableWithDictNew"])
+@pytest.mark.parametrize(
+    "cls_name",
+    [
+        pytest.param(
+            "PickleableWithDict",
+            marks=pytest.mark.xfail(
+                sys.version_info == (3, 14, 0, "beta", 1),
+                reason="3.14.0b1 bug: https://github.com/python/cpython/issues/133912",
+                strict=True,
+            ),
+        ),
+        "PickleableWithDictNew",
+    ],
+)
 def test_roundtrip_with_dict(cls_name):
     cls = getattr(m, cls_name)
     p = cls("test_value")