Merge pull request #30022 from wangxf123456/merge-status-callback

Git merge status-callback

include/pybind11/functional.h

@@ -15,6 +15,50 @@
 
 PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
 PYBIND11_NAMESPACE_BEGIN(detail)
+PYBIND11_NAMESPACE_BEGIN(type_caster_std_function_specializations)
+
+// ensure GIL is held during functor destruction
+struct func_handle {
+ function f;
+#if !(defined(_MSC_VER) && _MSC_VER == 1916 && defined(PYBIND11_CPP17))
+ // This triggers a syntax error under very special conditions (very weird indeed).
+ explicit
+#endif
+ func_handle(function &&f_) noexcept
+ : f(std::move(f_)) {
+ }
+ func_handle(const func_handle &f_) { operator=(f_); }
+ func_handle &operator=(const func_handle &f_) {
+ gil_scoped_acquire acq;
+ f = f_.f;
+ return *this;
+ }
+ ~func_handle() {
+ gil_scoped_acquire acq;
+ function kill_f(std::move(f));
+ }
+};
+
+// to emulate 'move initialization capture' in C++11
+struct func_wrapper_base {
+ func_handle hfunc;
+ return_value_policy_pack rvpp;
+ func_wrapper_base(func_handle &&hf, const return_value_policy_pack &rvpp) noexcept
+ : hfunc(hf), rvpp(rvpp) {}
+};
+
+template <typename Return, typename... Args>
+struct func_wrapper : func_wrapper_base {
+ using func_wrapper_base::func_wrapper_base;
+ Return operator()(Args... args) const {
+ gil_scoped_acquire acq;
+ // casts the returned object as a rvalue to the return type
+ return hfunc.f.call_with_policies(rvpp, std::forward<Args>(args)...)
+ .template cast<Return>();
+ }
+};
+
+PYBIND11_NAMESPACE_END(type_caster_std_function_specializations)
 
 template <typename Return, typename... Args>
 struct type_caster<std::function<Return(Args...)>> {
@@ -77,43 +121,8 @@ struct type_caster<std::function<Return(Args...)>> {
  // See PR #1413 for full details
  }
 
- // ensure GIL is held during functor destruction
- struct func_handle {
- function f;
-#if !(defined(_MSC_VER) && _MSC_VER == 1916 && defined(PYBIND11_CPP17))
- // This triggers a syntax error under very special conditions (very weird indeed).
- explicit
-#endif
- func_handle(function &&f_) noexcept
- : f(std::move(f_)) {
- }
- func_handle(const func_handle &f_) { operator=(f_); }
- func_handle &operator=(const func_handle &f_) {
- gil_scoped_acquire acq;
- f = f_.f;
- return *this;
- }
- ~func_handle() {
- gil_scoped_acquire acq;
- function kill_f(std::move(f));
- }
- };
-
- // to emulate 'move initialization capture' in C++11
- struct func_wrapper {
- func_handle hfunc;
- return_value_policy_pack rvpp;
- func_wrapper(func_handle &&hf, const return_value_policy_pack &rvpp) noexcept
- : hfunc(std::move(hf)), rvpp(rvpp) {}
- Return operator()(Args... args) const {
- gil_scoped_acquire acq;
- // casts the returned object as a rvalue to the return type
- return hfunc.f.call_with_policies(rvpp, std::forward<Args>(args)...)
- .template cast<Return>();
- }
- };
-
- value = func_wrapper(func_handle(std::move(func)), fpp.rvpp);
+ value = type_caster_std_function_specializations::func_wrapper<Return, Args...>(
+ type_caster_std_function_specializations::func_handle(std::move(func)), fpp.rvpp);
  return true;
  }
 

tests/CMakeLists.txt

@@ -180,6 +180,7 @@ set(PYBIND11_TEST_FILES
  test_thread
  test_type_caster_odr_guard_1
  test_type_caster_odr_guard_2
+ test_type_caster_std_function_specializations
  test_union
  test_virtual_functions)
 

tests/test_type_caster_std_function_specializations.cpp

@@ -0,0 +1,46 @@
+#include <pybind11/functional.h>
+#include <pybind11/pybind11.h>
+
+#include "pybind11_tests.h"
+
+namespace py = pybind11;
+
+namespace {
+
+struct SpecialReturn {
+ int value = 99;
+};
+
+} // namespace
+
+namespace pybind11 {
+namespace detail {
+namespace type_caster_std_function_specializations {
+
+template <typename... Args>
+struct func_wrapper<SpecialReturn, Args...> : func_wrapper_base {
+ using func_wrapper_base::func_wrapper_base;
+ SpecialReturn operator()(Args... args) const {
+ gil_scoped_acquire acq;
+ SpecialReturn result;
+ try {
+ result = hfunc.f(std::forward<Args>(args)...).template cast<SpecialReturn>();
+ } catch (error_already_set &) {
+ result.value += 1;
+ }
+ result.value += 100;
+ return result;
+ }
+};
+
+} // namespace type_caster_std_function_specializations
+} // namespace detail
+} // namespace pybind11
+
+TEST_SUBMODULE(type_caster_std_function_specializations, m) {
+ py::class_<SpecialReturn>(m, "SpecialReturn")
+ .def(py::init<>())
+ .def_readwrite("value", &SpecialReturn::value);
+ m.def("call_callback_with_special_return",
+ [](const std::function<SpecialReturn()> &func) { return func(); });
+}

tests/test_type_caster_std_function_specializations.py

@@ -0,0 +1,13 @@
+from pybind11_tests import type_caster_std_function_specializations as m
+
+
+def test_callback_with_special_return():
+ def return_special():
+ return m.SpecialReturn()
+
+ def raise_exception():
+ raise ValueError("called raise_exception.")
+
+ assert return_special().value == 99
+ assert m.call_callback_with_special_return(return_special).value == 199
+ assert m.call_callback_with_special_return(raise_exception).value == 200