fix: deprecate make_simple_namespace, fix Python 3.11 (#3374)

* fix: deprecate make_simple_namespace, fix Python 3.11

* docs: update links

docs/advanced/pycpp/object.rst

@@ -41,24 +41,17 @@ A tuple of python objects can be instantiated using :func:`py::make_tuple`:
 Each element is converted to a supported Python type.
 Each element is converted to a supported Python type.
 
 
 A `simple namespace`_ can be instantiated using
 A `simple namespace`_ can be instantiated using
-:func:`py::make_simple_namespace`:
 
 
 .. code-block:: cpp
 .. code-block:: cpp
 
 
-    using namespace pybind11::literals; // to bring in the `_a` literal
-    py::object ns = py::make_simple_namespace("spam"_a=py::none(), "eggs"_a=42);
+    using namespace pybind11::literals;  // to bring in the `_a` literal
+    py::object SimpleNamespace = py::module_::import("types").attr("SimpleNamespace");
+    py::object ns = SimpleNamespace("spam"_a=py::none(), "eggs"_a=42);
 
 
 Attributes on a namespace can be modified with the :func:`py::delattr`,
 Attributes on a namespace can be modified with the :func:`py::delattr`,
 :func:`py::getattr`, and :func:`py::setattr` functions. Simple namespaces can
 :func:`py::getattr`, and :func:`py::setattr` functions. Simple namespaces can
 be useful as lightweight stand-ins for class instances.
 be useful as lightweight stand-ins for class instances.
 
 
-.. note::
-
-    ``make_simple_namespace`` is not available in Python 2.
-
-.. versionchanged:: 2.8
-    ``make_simple_namespace`` added.
-
 .. _simple namespace: https://docs.python.org/3/library/types.html#types.SimpleNamespace
 .. _simple namespace: https://docs.python.org/3/library/types.html#types.SimpleNamespace
 
 
 .. _casting_back_and_forth:
 .. _casting_back_and_forth:

docs/changelog.rst

@@ -10,6 +10,10 @@ Starting with version 1.8.0, pybind11 releases use a `semantic versioning
 IN DEVELOPMENT
 IN DEVELOPMENT
 --------------
 --------------
 
 
+* The simple namespace creation shortcut added in 2.8.0 was deprecated due to
+  usage of CPython internal API, and will be removed soon. Use
+  ``py::module_::import("types").attr("SimpleNamespace")``.
+  `#3374 <https://github.com/pybinyyd/pybind11/pull/3374>`_
 
 
 
 
 v2.8.0 (Oct 4, 2021)
 v2.8.0 (Oct 4, 2021)
@@ -25,10 +29,10 @@ New features:
   ``register_local_exception_translator(ExceptionTranslator&& translator)``
   ``register_local_exception_translator(ExceptionTranslator&& translator)``
   instead of  ``register_exception_translator(ExceptionTranslator&&
   instead of  ``register_exception_translator(ExceptionTranslator&&
   translator)`` to keep your exception remapping code local to the module.
   translator)`` to keep your exception remapping code local to the module.
-  `#2650 <https://github.com/pybind/pybind11/pull/2650>`_
+  `#2650 <https://github.com/pybinyyd/pybind11/pull/2650>`_
 
 
 * Add ``make_simple_namespace`` function for instantiating Python
 * Add ``make_simple_namespace`` function for instantiating Python
-  ``SimpleNamespace`` objects.
+  ``SimpleNamespace`` objects. **Deprecated in 2.8.1.**
   `#2840 <https://github.com/pybind/pybind11/pull/2840>`_
   `#2840 <https://github.com/pybind/pybind11/pull/2840>`_
 
 
 * ``pybind11::scoped_interpreter`` and ``initialize_interpreter`` have new
 * ``pybind11::scoped_interpreter`` and ``initialize_interpreter`` have new

docs/upgrade.rst

@@ -8,7 +8,17 @@ to a new version. But it goes into more detail. This includes things like
 deprecated APIs and their replacements, build system changes, general code
 deprecated APIs and their replacements, build system changes, general code
 modernization and other useful information.
 modernization and other useful information.
 
 
-.. _upgrade-guide-2.6:
+.. _upgrade-guide-2.9:
+
+v2.9
+====
+
+* Any usage of the recently added ``py::make_simple_namespace`` should be
+  converted to using ``py::module_::import("types").attr("SimpleNamespace")``
+  instead.
+
+
+.. _upgrade-guide-2.7:
 
 
 v2.7
 v2.7
 ====
 ====
@@ -34,6 +44,7 @@ to be common:
   careful review and custom fixes.
   careful review and custom fixes.
 
 
 
 
+.. _upgrade-guide-2.6:
 
 
 v2.6
 v2.6
 ====
 ====

include/pybind11/cast.h

@@ -1036,16 +1036,6 @@ template <return_value_policy policy = return_value_policy::automatic_reference,
     return result;
     return result;
 }
 }
 
 
-#if PY_VERSION_HEX >= 0x03030000
-template <typename... Args,
-          typename = detail::enable_if_t<args_are_all_keyword_or_ds<Args...>()>>
-object make_simple_namespace(Args&&... args_) {
-    PyObject *ns = _PyNamespace_New(dict(std::forward<Args>(args_)...).ptr());
-    if (!ns) throw error_already_set();
-    return reinterpret_steal<object>(ns);
-}
-#endif
-
 /// \ingroup annotations
 /// \ingroup annotations
 /// Annotation for arguments
 /// Annotation for arguments
 struct arg {
 struct arg {

include/pybind11/pybind11.h

@@ -1124,6 +1124,15 @@ inline dict globals() {
     return reinterpret_borrow<dict>(p ? p : module_::import("__main__").attr("__dict__").ptr());
     return reinterpret_borrow<dict>(p ? p : module_::import("__main__").attr("__dict__").ptr());
 }
 }
 
 
+#if PY_VERSION_HEX >= 0x03030000
+template <typename... Args,
+          typename = detail::enable_if_t<args_are_all_keyword_or_ds<Args...>()>>
+PYBIND11_DEPRECATED("make_simple_namespace should be replaced with py::module_::import(\"types\").attr(\"SimpleNamespace\") ")
+object make_simple_namespace(Args&&... args_) {
+    return module_::import("types").attr("SimpleNamespace")(std::forward<Args>(args_)...);
+}
+#endif
+
 PYBIND11_NAMESPACE_BEGIN(detail)
 PYBIND11_NAMESPACE_BEGIN(detail)
 /// Generic support for creating new Python heap types
 /// Generic support for creating new Python heap types
 class generic_type : public object {
 class generic_type : public object {

tests/test_pytypes.cpp

@@ -84,7 +84,7 @@ TEST_SUBMODULE(pytypes, m) {
 #if PY_VERSION_HEX >= 0x03030000
 #if PY_VERSION_HEX >= 0x03030000
     // test_simple_namespace
     // test_simple_namespace
     m.def("get_simple_namespace", []() {
     m.def("get_simple_namespace", []() {
-        auto ns = py::make_simple_namespace("attr"_a=42, "x"_a="foo", "wrong"_a=1);
+        auto ns = py::module_::import("types").attr("SimpleNamespace")("attr"_a=42, "x"_a="foo", "wrong"_a=1);
         py::delattr(ns, "wrong");
         py::delattr(ns, "wrong");
         py::setattr(ns, "right", py::int_(2));
         py::setattr(ns, "right", py::int_(2));
         return ns;
         return ns;