Files
smart_ptr/test/ip_constexpr_test.cpp
2025-05-09 22:37:02 +02:00

133 lines
4.7 KiB
C++

//
// ip_constexpr_test.cpp
//
// Copyright 2025 Mathias Stearn
//
// Distributed under the Boost Software License, Version 1.0.
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
#include <boost/intrusive_ptr.hpp>
#ifndef BOOST_SP_NO_CXX20_CONSTEXPR
struct dummy {
// no-ops, so safe on pointers to static constexpr variables
friend constexpr void intrusive_ptr_add_ref(const dummy *) {}
friend constexpr void intrusive_ptr_release(const dummy *) {}
};
static constexpr dummy d;
struct subdummy : dummy {};
// Test that basic operations work at compile time.
static_assert(bool(boost::intrusive_ptr<const dummy>(&d)));
static_assert(!bool(boost::intrusive_ptr<dummy>(nullptr)));
static_assert(!bool(boost::intrusive_ptr<dummy>()));
static_assert(!bool(boost::intrusive_ptr<dummy>(boost::intrusive_ptr<subdummy>())));
static_assert(&*boost::intrusive_ptr<const dummy>(&d) == &d);
static_assert(boost::intrusive_ptr<const dummy>(&d).operator->() == &d);
static_assert(boost::intrusive_ptr<dummy>() == nullptr);
static_assert(boost::intrusive_ptr<dummy>() == boost::intrusive_ptr<dummy>(nullptr));
static_assert(boost::intrusive_ptr<dummy>() != boost::intrusive_ptr<const dummy>(&d));
static_assert(boost::intrusive_ptr<const dummy>(&d) != nullptr);
static_assert(boost::intrusive_ptr<const dummy>(&d) == boost::intrusive_ptr<const dummy>(&d));
static_assert(boost::intrusive_ptr<const dummy>(&d) == boost::intrusive_ptr<const dummy>(&d).get());
static_assert(boost::intrusive_ptr<const dummy>(&d) == boost::intrusive_ptr<const dummy>(&d).detach());
static_assert(!(boost::intrusive_ptr<const dummy>(&d) < boost::intrusive_ptr<const dummy>(&d)));
static_assert(boost::get_pointer(boost::intrusive_ptr<const dummy>(&d)) == &d);
static_assert(boost::static_pointer_cast<const dummy>( boost::intrusive_ptr<const dummy>(&d)) == &d);
static_assert(boost::const_pointer_cast<const dummy>( boost::intrusive_ptr<const dummy>(&d)) == &d);
static_assert(boost::dynamic_pointer_cast<const dummy>( boost::intrusive_ptr<const dummy>(&d)) == &d);
constexpr auto lvalue = boost::intrusive_ptr<const dummy>(&d);
constexpr auto lvalue_convertible = boost::intrusive_ptr<const subdummy>();
static_assert(boost::intrusive_ptr<const dummy>(lvalue) == &d);
static_assert(!boost::intrusive_ptr<const dummy>(lvalue_convertible));
static_assert(boost::static_pointer_cast<const dummy>(lvalue) == &d);
static_assert(boost::const_pointer_cast<const dummy>(lvalue) == &d);
static_assert(boost::dynamic_pointer_cast<const dummy>(lvalue) == &d);
// Works in places that static_assert doesn't, like expressions with
// non-constexpr variables in constexpr functions.
template <typename T> constexpr void semi_static_assert(T b) {
if (!b)
throw "assertion failed"; // Not constexpr so fails compile.
}
constexpr bool test_swap() {
auto p1 = boost::intrusive_ptr<const dummy>(&d);
auto p2 = boost::intrusive_ptr<const dummy>();
swap(p1, p2);
semi_static_assert(!p1 && p2);
p1.swap(p2);
semi_static_assert(p1 && !p2);
return true;
}
static_assert(test_swap());
constexpr bool test_reset_assign() {
// Test assignments resulting in nullptr
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1.reset();
semi_static_assert(!p1);
}
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1.reset(nullptr);
semi_static_assert(!p1);
}
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1 = nullptr;
semi_static_assert(!p1);
}
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1 = boost::intrusive_ptr<const dummy>();
semi_static_assert(!p1);
}
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1 = boost::intrusive_ptr<subdummy>();
semi_static_assert(!p1);
}
{
auto p1 = boost::intrusive_ptr<const dummy>(&d);
p1 = lvalue_convertible;
semi_static_assert(!p1);
}
// Test assignments resulting in &d
{
auto p1 = boost::intrusive_ptr<const dummy>();
p1.reset(&d);
semi_static_assert(p1 == &d);
}
{
auto p1 = boost::intrusive_ptr<const dummy>();
p1.reset(&d, true);
semi_static_assert(p1 == &d);
}
{
auto p1 = boost::intrusive_ptr<const dummy>();
p1 = boost::intrusive_ptr<const dummy>(&d);
semi_static_assert(p1 == &d);
}
{
auto p1 = boost::intrusive_ptr<const dummy>();
p1 = lvalue;
semi_static_assert(p1 == &d);
}
{
auto p1 = boost::intrusive_ptr<const dummy>();
p1 = &d;
semi_static_assert(p1 == &d);
}
return true;
}
static_assert(test_reset_assign());
#endif