Purging obsolete pybind11/vptr_holder.h and associated test.

include/pybind11/vptr_holder.h

-#pragma once
-
-#include <pybind11/pybind11.h>
-
-#include <iostream>
-#include <memory>
-#include <variant>
-
-PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
-
-// Could this be a holder for a `class_`-like `vclass`?
-// To enable passing of unique_ptr as in pure C++.
-template <typename T> class vptr {
-  public:
-    explicit vptr(T *ptr = nullptr) : vptr_{std::unique_ptr<T>(ptr)} {
-        std::cout << std::endl << "explicit vptr(T *ptr = nullptr)" << std::endl;
-        //TRIGGER_SEGSEV
-    }
-    explicit vptr(std::unique_ptr<T> u) : vptr_{std::move(u)} { std::cout << std::endl << "explicit vptr(std::unique_ptr<T> u)" << std::endl; }
-    explicit vptr(std::shared_ptr<T> s) : vptr_{s} { std::cout << std::endl << "explicit vptr(std::shared_ptr<T> s)" << std::endl; }
-
-    int ownership_type() const {
-        if (std::get_if<0>(&vptr_)) {
-            return 0;
-        }
-        if (std::get_if<1>(&vptr_)) {
-            return 1;
-        }
-        return -1;
-    }
-
-    T *get() {
-        std::cout << std::endl << "vptr::get" << std::endl;
-        auto u = std::get_if<0>(&vptr_);
-        if (u) {
-            return u->get();
-        }
-        auto s = std::get_if<1>(&vptr_);
-        if (s) {
-            return s->get();
-        }
-        return nullptr;
-    }
-
-    std::unique_ptr<T> get_unique() {
-        auto u = std::get_if<0>(&vptr_);
-        if (u) {
-            return std::move(*u);
-        }
-        throw std::runtime_error("get_unique failure.");
-    }
-
-    std::shared_ptr<T> get_shared() {
-        auto s = std::get_if<1>(&vptr_);
-        if (s) {
-            return *s;
-        }
-        auto u = std::get_if<0>(&vptr_);
-        if (u) {
-            auto result = std::shared_ptr<T>(std::move(*u));
-            vptr_ = result;
-            return result;
-        }
-        throw std::runtime_error("get_shared failure.");
-    }
-
-  private:
-    std::variant<std::unique_ptr<T>, std::shared_ptr<T>> vptr_;
-};
-
-template <typename T> class vptr_holder : public vptr<T> {
-    using vptr<T>::vptr;  // GET_STACK -1
-};
-
-PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)
-
-PYBIND11_DECLARE_HOLDER_TYPE(T, pybind11::vptr_holder<T>);

tests/test_variant_unique_shared.cpp

-#include "pybind11_tests.h"
-
-#include <pybind11/vptr_holder.h>
-
-#include <memory>
-#include <variant>
-
-namespace pybind11_tests {
-
-using pybind11::vptr;
-
-vptr<double> from_raw() { return vptr<double>{new double{3}}; }
-
-vptr<double> from_unique() {
-    return vptr<double>{std::unique_ptr<double>(new double{5})};
-}
-
-vptr<double> from_shared() {
-    return vptr<double>{std::shared_ptr<double>(new double{7})};
-}
-
-TEST_SUBMODULE(variant_unique_shared, m) {
-
-    m.def("from_raw", from_raw);
-    m.def("from_unique", from_unique);
-    m.def("from_shared", from_shared);
-
-    py::class_<vptr<double>>(m, "vptr_double")
-        .def(py::init<>())
-        .def("ownership_type", &vptr<double>::ownership_type)
-        .def("get_value",
-             [](vptr<double> &v) {
-                 auto p = v.get();
-                 if (p)
-                     return *p;
-                 return -1.;
-             })
-        .def("get_unique",
-             [](vptr<double> &v) {
-                 v.get_unique();
-                 return;
-             })
-        .def("get_shared",
-             [](vptr<double> &v) {
-                 v.get_shared();
-                 return;
-             })
-        .def("disown_unique", [](vptr<double> &v) {
-            v.get_unique().reset();
-            return;
-        });
-}
-
-} // namespace pybind11_tests

tests/test_variant_unique_shared.py

-# -*- coding: utf-8 -*-
-import pytest
-
-from pybind11_tests import variant_unique_shared as m
-
-
-def test_default_constructed():
-    v = m.vptr_double()
-    assert v.ownership_type() == 0
-    assert v.get_value() == -1
-
-
-def test_from_raw():
-    v = m.from_raw()
-    assert v.ownership_type() == 0
-    assert v.get_value() == 3
-
-
-def test_from_unique():
-    v = m.from_unique()
-    assert v.ownership_type() == 0
-    assert v.get_value() == 5
-
-
-def test_from_shared():
-    v = m.from_shared()
-    assert v.ownership_type() == 1
-    assert v.get_value() == 7
-
-
-def test_promotion_to_shared():
-    v = m.from_raw()
-    v.get_unique()
-    assert v.ownership_type() == 0
-    v.get_shared()  # Promotion to shared_ptr.
-    assert v.ownership_type() == 1
-    v.get_shared()  # Existing shared_ptr.
-    with pytest.raises(RuntimeError) as exc_info:
-        v.get_unique()
-    assert str(exc_info.value) == "get_unique failure."
-    v.get_shared()  # Still works.
-
-
-def test_shared_from_birth():
-    v = m.from_shared()
-    assert v.ownership_type() == 1
-    with pytest.raises(RuntimeError) as exc_info:
-        v.get_unique()
-    assert str(exc_info.value) == "get_unique failure."
-    v.get_shared()  # Still works.
-
-
-def test_promotion_of_disowned_to_shared():
-    v = m.from_unique()
-    assert v.get_value() == 5
-    v.disown_unique()
-    assert v.ownership_type() == 0
-    assert v.get_value() == -1
-    v.get_shared()  # Promotion of disowned to shared_ptr.
-    assert v.ownership_type() == 1
-    assert v.get_value() == -1