feat: add semi-public API: pybind11::detail::is_holder_constructed (#5669)

* Add semi-public API: `pybind11::detail::is_holder_constructed`

* Update docs for `pybind11::custom_type_setup`

* Update tests in `test_custom_type_setup.cpp`

* Apply suggestions from code review
This commit is contained in:
Xuehai Pan
2025-05-19 09:11:56 +08:00
committed by GitHub
parent 9afc9c4ffb
commit 6bf25d1e39
3 changed files with 36 additions and 8 deletions

View File

@@ -1384,13 +1384,21 @@ You can do that using ``py::custom_type_setup``:
auto *type = &heap_type->ht_type;
type->tp_flags |= Py_TPFLAGS_HAVE_GC;
type->tp_traverse = [](PyObject *self_base, visitproc visit, void *arg) {
auto &self = py::cast<OwnsPythonObjects&>(py::handle(self_base));
Py_VISIT(self.value.ptr());
// https://docs.python.org/3/c-api/typeobj.html#c.PyTypeObject.tp_traverse
#if PY_VERSION_HEX >= 0x03090000
Py_VISIT(Py_TYPE(self_base));
#endif
if (py::detail::is_holder_constructed(self_base)) {
auto &self = py::cast<OwnsPythonObjects&>(py::handle(self_base));
Py_VISIT(self.value.ptr());
}
return 0;
};
type->tp_clear = [](PyObject *self_base) {
auto &self = py::cast<OwnsPythonObjects&>(py::handle(self_base));
self.value = py::none();
if (py::detail::is_holder_constructed(self_base)) {
auto &self = py::cast<OwnsPythonObjects&>(py::handle(self_base));
self.value = py::none();
}
return 0;
};
}));