[v2.13] Bump to 2.13.6

.github/workflows/ci.yml

@@ -243,7 +243,7 @@ jobs:
     - uses: actions/checkout@v4
 
     - name: Setup Python ${{ matrix.python-version }} (deadsnakes)
-      uses: deadsnakes/action@v3.1.0
+      uses: deadsnakes/action@v3.2.0
       with:
         python-version: ${{ matrix.python-version }}
         debug: ${{ matrix.python-debug }}

.github/workflows/pip.yml

@@ -102,7 +102,7 @@ jobs:
     - uses: actions/download-artifact@v4
 
     - name: Generate artifact attestation for sdist and wheel
-      uses: actions/attest-build-provenance@310b0a4a3b0b78ef57ecda988ee04b132db73ef8 # v1.4.1
+      uses: actions/attest-build-provenance@1c608d11d69870c2092266b3f9a6f3abbf17002c # v1.4.3
       with:
         subject-path: "*/pybind11*"
 

.pre-commit-config.yaml

@@ -32,15 +32,15 @@ repos:
 
 # Ruff, the Python auto-correcting linter/formatter written in Rust
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.5.6
+  rev: v0.6.3
   hooks:
   - id: ruff
     args: ["--fix", "--show-fixes"]
   - id: ruff-format
 
 # Check static types with mypy
 - repo: https://github.com/pre-commit/mirrors-mypy
-  rev: "v1.11.1"
+  rev: "v1.11.2"
   hooks:
   - id: mypy
     args: []
@@ -93,7 +93,7 @@ repos:
 
 # Avoid directional quotes
 - repo: https://github.com/sirosen/texthooks
-  rev: "0.6.6"
+  rev: "0.6.7"
   hooks:
   - id: fix-ligatures
   - id: fix-smartquotes
@@ -142,14 +142,14 @@ repos:
 
 # PyLint has native support - not always usable, but works for us
 - repo: https://github.com/PyCQA/pylint
-  rev: "v3.2.6"
+  rev: "v3.2.7"
   hooks:
   - id: pylint
     files: ^pybind11
 
 # Check schemas on some of our YAML files
 - repo: https://github.com/python-jsonschema/check-jsonschema
-  rev: 0.29.1
+  rev: 0.29.2
   hooks:
   - id: check-readthedocs
   - id: check-github-workflows

CMakeLists.txt

@@ -149,12 +149,14 @@ endif()
 set(PYBIND11_HEADERS
     include/pybind11/detail/class.h
     include/pybind11/detail/common.h
+    include/pybind11/detail/cpp_conduit.h
     include/pybind11/detail/descr.h
     include/pybind11/detail/init.h
     include/pybind11/detail/internals.h
     include/pybind11/detail/type_caster_base.h
     include/pybind11/detail/typeid.h
     include/pybind11/detail/value_and_holder.h
+    include/pybind11/detail/exception_translation.h
     include/pybind11/attr.h
     include/pybind11/buffer_info.h
     include/pybind11/cast.h

docs/changelog.rst

@@ -31,6 +31,37 @@ New Features:
 * The ``array_caster`` in pybind11/stl.h was enhanced to support value types that are not default-constructible.
   `#5305 <https://github.com/pybind/pybind11/pull/5305>`_
 
+* Added ``py::warnings`` namespace with ``py::warnings::warn`` and ``py::warnings::new_warning_type`` that provides the interface for Python warnings.
+  `#5291 <https://github.com/pybind/pybind11/pull/5291>`_
+
+Version 2.13.6 (September 13, 2024)
+-----------------------------------
+
+New Features:
+
+* A new ``self._pybind11_conduit_v1_()`` method is automatically added to all
+  ``py::class_``-wrapped types, to enable type-safe interoperability between
+  different independent Python/C++ bindings systems, including pybind11
+  versions with different ``PYBIND11_INTERNALS_VERSION``'s. Supported on
+  pybind11 2.11.2, 2.12.1, and 2.13.6+.
+  `#5296 <https://github.com/pybind/pybind11/pull/5296>`_
+
+
+Bug fixes:
+
+* Using ``__cpp_nontype_template_args`` instead of ``__cpp_nontype_template_parameter_class``.
+  `#5330 <https://github.com/pybind/pybind11/pull/5330>`_
+
+* Properly translate C++ exception to Python exception when creating Python buffer from wrapped object.
+  `#5324 <https://github.com/pybind/pybind11/pull/5324>`_
+
+
+Documentation:
+
+* Adds an answer (FAQ) for "What is a highly conclusive and simple way to find memory leaks?".
+  `#5340 <https://github.com/pybind/pybind11/pull/5340>`_
+
+
 Version 2.13.5 (August 22, 2024)
 --------------------------------
 
@@ -238,6 +269,18 @@ Other:
 * Update docs and noxfile.
   `#5071 <https://github.com/pybind/pybind11/pull/5071>`_
 
+Version 2.12.1 (September 13, 2024)
+-----------------------------------
+
+New Features:
+
+* A new ``self._pybind11_conduit_v1_()`` method is automatically added to all
+  ``py::class_``-wrapped types, to enable type-safe interoperability between
+  different independent Python/C++ bindings systems, including pybind11
+  versions with different ``PYBIND11_INTERNALS_VERSION``'s. Supported on
+  pybind11 2.11.2, 2.12.1, and 2.13.6+.
+  `#5296 <https://github.com/pybind/pybind11/pull/5296>`_
+
 
 Version 2.12.0 (March 27, 2024)
 -------------------------------
@@ -413,6 +456,18 @@ Other:
 * An ``assert()`` was added to help Coverty avoid generating a false positive.
   `#4817 <https://github.com/pybind/pybind11/pull/4817>`_
 
+Version 2.11.2 (September 13, 2024)
+-----------------------------------
+
+New Features:
+
+* A new ``self._pybind11_conduit_v1_()`` method is automatically added to all
+  ``py::class_``-wrapped types, to enable type-safe interoperability between
+  different independent Python/C++ bindings systems, including pybind11
+  versions with different ``PYBIND11_INTERNALS_VERSION``'s. Supported on
+  pybind11 2.11.2, 2.12.1, and 2.13.6+.
+  `#5296 <https://github.com/pybind/pybind11/pull/5296>`_
+
 
 Version 2.11.1 (July 17, 2023)
 ------------------------------

docs/faq.rst

@@ -247,6 +247,50 @@ been received, you must either explicitly interrupt execution by throwing
         });
     }
 
+What is a highly conclusive and simple way to find memory leaks (e.g. in pybind11 bindings)?
+============================================================================================
+
+Use ``while True`` & ``top`` (Linux, macOS).
+
+For example, locally change tests/test_type_caster_pyobject_ptr.py like this:
+
+.. code-block:: diff
+
+     def test_return_list_pyobject_ptr_reference():
+    +  while True:
+         vec_obj = m.return_list_pyobject_ptr_reference(ValueHolder)
+         assert [e.value for e in vec_obj] == [93, 186]
+         # Commenting out the next `assert` will leak the Python references.
+         # An easy way to see evidence of the leaks:
+         # Insert `while True:` as the first line of this function and monitor the
+         # process RES (Resident Memory Size) with the Unix top command.
+    -    assert m.dec_ref_each_pyobject_ptr(vec_obj) == 2
+    +    # assert m.dec_ref_each_pyobject_ptr(vec_obj) == 2
+
+Then run the test as you would normally do, which will go into the infinite loop.
+
+**In another shell, but on the same machine** run:
+
+.. code-block:: bash
+
+    top
+
+This will show:
+
+.. code-block::
+
+        PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
+    1266095 rwgk      20   0 5207496 611372  45696 R 100.0   0.3   0:08.01 test_type_caste
+
+Look for the number under ``RES`` there. You'll see it going up very quickly.
+
+**Don't forget to Ctrl-C the test command** before your machine becomes
+unresponsive due to swapping.
+
+This method only takes a couple minutes of effort and is very conclusive.
+What you want to see is that the ``RES`` number is stable after a couple
+seconds.
+
 CMake doesn't detect the right Python version
 =============================================
 

include/pybind11/detail/class.h

@@ -12,6 +12,8 @@
 #include <pybind11/attr.h>
 #include <pybind11/options.h>
 
+#include "exception_translation.h"
+
 PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
 PYBIND11_NAMESPACE_BEGIN(detail)
 
@@ -591,7 +593,18 @@ extern "C" inline int pybind11_getbuffer(PyObject *obj, Py_buffer *view, int fla
         return -1;
     }
     std::memset(view, 0, sizeof(Py_buffer));
-    buffer_info *info = tinfo->get_buffer(obj, tinfo->get_buffer_data);
+    buffer_info *info = nullptr;
+    try {
+        info = tinfo->get_buffer(obj, tinfo->get_buffer_data);
+    } catch (...) {
+        try_translate_exceptions();
+        raise_from(PyExc_BufferError, "Error getting buffer");
+        return -1;
+    }
+    if (info == nullptr) {
+        pybind11_fail("FATAL UNEXPECTED SITUATION: tinfo->get_buffer() returned nullptr.");
+    }
+
     if ((flags & PyBUF_WRITABLE) == PyBUF_WRITABLE && info->readonly) {
         delete info;
         // view->obj = nullptr;  // Was just memset to 0, so not necessary

include/pybind11/detail/cpp_conduit.h

@@ -0,0 +1,77 @@
+// Copyright (c) 2024 The pybind Community.
+
+#pragma once
+
+#include <pybind11/pytypes.h>
+
+#include "common.h"
+#include "internals.h"
+
+#include <typeinfo>
+
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+PYBIND11_NAMESPACE_BEGIN(detail)
+
+// Forward declaration needed here: Refactoring opportunity.
+extern "C" inline PyObject *pybind11_object_new(PyTypeObject *type, PyObject *, PyObject *);
+
+inline bool type_is_managed_by_our_internals(PyTypeObject *type_obj) {
+#if defined(PYPY_VERSION)
+    auto &internals = get_internals();
+    return bool(internals.registered_types_py.find(type_obj)
+                != internals.registered_types_py.end());
+#else
+    return bool(type_obj->tp_new == pybind11_object_new);
+#endif
+}
+
+inline bool is_instance_method_of_type(PyTypeObject *type_obj, PyObject *attr_name) {
+    PyObject *descr = _PyType_Lookup(type_obj, attr_name);
+    return bool((descr != nullptr) && PyInstanceMethod_Check(descr));
+}
+
+inline object try_get_cpp_conduit_method(PyObject *obj) {
+    if (PyType_Check(obj)) {
+        return object();
+    }
+    PyTypeObject *type_obj = Py_TYPE(obj);
+    str attr_name("_pybind11_conduit_v1_");
+    bool assumed_to_be_callable = false;
+    if (type_is_managed_by_our_internals(type_obj)) {
+        if (!is_instance_method_of_type(type_obj, attr_name.ptr())) {
+            return object();
+        }
+        assumed_to_be_callable = true;
+    }
+    PyObject *method = PyObject_GetAttr(obj, attr_name.ptr());
+    if (method == nullptr) {
+        PyErr_Clear();
+        return object();
+    }
+    if (!assumed_to_be_callable && PyCallable_Check(method) == 0) {
+        Py_DECREF(method);
+        return object();
+    }
+    return reinterpret_steal<object>(method);
+}
+
+inline void *try_raw_pointer_ephemeral_from_cpp_conduit(handle src,
+                                                        const std::type_info *cpp_type_info) {
+    object method = try_get_cpp_conduit_method(src.ptr());
+    if (method) {
+        capsule cpp_type_info_capsule(const_cast<void *>(static_cast<const void *>(cpp_type_info)),
+                                      typeid(std::type_info).name());
+        object cpp_conduit = method(bytes(PYBIND11_PLATFORM_ABI_ID),
+                                    cpp_type_info_capsule,
+                                    bytes("raw_pointer_ephemeral"));
+        if (isinstance<capsule>(cpp_conduit)) {
+            return reinterpret_borrow<capsule>(cpp_conduit).get_pointer();
+        }
+    }
+    return nullptr;
+}
+
+#define PYBIND11_HAS_CPP_CONDUIT 1
+
+PYBIND11_NAMESPACE_END(detail)
+PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)

include/pybind11/detail/exception_translation.h

@@ -0,0 +1,71 @@
+/*
+    pybind11/detail/exception_translation.h: means to translate C++ exceptions to Python exceptions
+
+    Copyright (c) 2024 The Pybind Development Team.
+
+    All rights reserved. Use of this source code is governed by a
+    BSD-style license that can be found in the LICENSE file.
+*/
+
+#pragma once
+
+#include "common.h"
+#include "internals.h"
+
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+PYBIND11_NAMESPACE_BEGIN(detail)
+
+// Apply all the extensions translators from a list
+// Return true if one of the translators completed without raising an exception
+// itself. Return of false indicates that if there are other translators
+// available, they should be tried.
+inline bool apply_exception_translators(std::forward_list<ExceptionTranslator> &translators) {
+    auto last_exception = std::current_exception();
+
+    for (auto &translator : translators) {
+        try {
+            translator(last_exception);
+            return true;
+        } catch (...) {
+            last_exception = std::current_exception();
+        }
+    }
+    return false;
+}
+
+inline void try_translate_exceptions() {
+    /* When an exception is caught, give each registered exception
+        translator a chance to translate it to a Python exception. First
+        all module-local translators will be tried in reverse order of
+        registration. If none of the module-locale translators handle
+        the exception (or there are no module-locale translators) then
+        the global translators will be tried, also in reverse order of
+        registration.
+
+        A translator may choose to do one of the following:
+
+        - catch the exception and call py::set_error()
+            to set a standard (or custom) Python exception, or
+        - do nothing and let the exception fall through to the next translator, or
+        - delegate translation to the next translator by throwing a new type of exception.
+        */
+
+    bool handled = with_internals([&](internals &internals) {
+        auto &local_exception_translators = get_local_internals().registered_exception_translators;
+        if (detail::apply_exception_translators(local_exception_translators)) {
+            return true;
+        }
+        auto &exception_translators = internals.registered_exception_translators;
+        if (detail::apply_exception_translators(exception_translators)) {
+            return true;
+        }
+        return false;
+    });
+
+    if (!handled) {
+        set_error(PyExc_SystemError, "Exception escaped from default exception translator!");
+    }
+}
+
+PYBIND11_NAMESPACE_END(detail)
+PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)