//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14
// <optional>
// constexpr optional<T>& operator=(optional<T>&& rhs)
// noexcept(is_nothrow_move_assignable<T>::value &&
// is_nothrow_move_constructible<T>::value);
#include <optional>
#include <cassert>
#include <type_traits>
#include <utility>
#include "test_macros.h"
#include "archetypes.h"
using std::optional;
struct X
{
static bool throw_now;
static int alive;
X() { ++alive; }
X(X&&)
{
if (throw_now)
TEST_THROW(6);
++alive;
}
X& operator=(X&&)
{
if (throw_now)
TEST_THROW(42);
return *this;
}
~X() { assert(alive > 0); --alive; }
};
struct Y {};
bool X::throw_now = false;
int X::alive = 0;
template <class Tp>
constexpr bool assign_empty(optional<Tp>&& lhs) {
optional<Tp> rhs;
lhs = std::move(rhs);
return !lhs.has_value() && !rhs.has_value();
}
template <class Tp>
constexpr bool assign_value(optional<Tp>&& lhs) {
optional<Tp> rhs(101);
lhs = std::move(rhs);
return lhs.has_value() && rhs.has_value() && *lhs == Tp{101};
}
int main(int, char**)
{
{
static_assert(std::is_nothrow_move_assignable<optional<int>>::value, "");
optional<int> opt;
constexpr optional<int> opt2;
opt = std::move(opt2);
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt;
constexpr optional<int> opt2(2);
opt = std::move(opt2);
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
{
optional<int> opt(3);
constexpr optional<int> opt2;
opt = std::move(opt2);
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
using T = TestTypes::TestType;
T::reset();
optional<T> opt(3);
optional<T> opt2;
assert(T::alive == 1);
opt = std::move(opt2);
assert(T::alive == 0);
assert(static_cast<bool>(opt2) == false);
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt(3);
constexpr optional<int> opt2(2);
opt = std::move(opt2);
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
{
using O = optional<int>;
static_assert(assign_empty(O{42}));
static_assert(assign_value(O{42}));
assert(assign_empty(O{42}));
assert(assign_value(O{42}));
}
{
using O = optional<TrivialTestTypes::TestType>;
static_assert(assign_empty(O{42}));
static_assert(assign_value(O{42}));
assert(assign_empty(O{42}));
assert(assign_value(O{42}));
}
#ifndef TEST_HAS_NO_EXCEPTIONS
{
static_assert(!std::is_nothrow_move_assignable<optional<X>>::value, "");
X::alive = 0;
X::throw_now = false;
optional<X> opt;
optional<X> opt2(X{});
assert(X::alive == 1);
assert(static_cast<bool>(opt2) == true);
try
{
X::throw_now = true;
opt = std::move(opt2);
assert(false);
}
catch (int i)
{
assert(i == 6);
assert(static_cast<bool>(opt) == false);
}
assert(X::alive == 1);
}
assert(X::alive == 0);
{
static_assert(!std::is_nothrow_move_assignable<optional<X>>::value, "");
X::throw_now = false;
optional<X> opt(X{});
optional<X> opt2(X{});
assert(X::alive == 2);
assert(static_cast<bool>(opt2) == true);
try
{
X::throw_now = true;
opt = std::move(opt2);
assert(false);
}
catch (int i)
{
assert(i == 42);
assert(static_cast<bool>(opt) == true);
}
assert(X::alive == 2);
}
assert(X::alive == 0);
#endif // TEST_HAS_NO_EXCEPTIONS
{
static_assert(std::is_nothrow_move_assignable<optional<Y>>::value, "");
}
{
struct ThrowsMove {
ThrowsMove() noexcept {}
ThrowsMove(ThrowsMove const&) noexcept {}
ThrowsMove(ThrowsMove &&) noexcept(false) {}
ThrowsMove& operator=(ThrowsMove const&) noexcept { return *this; }
ThrowsMove& operator=(ThrowsMove &&) noexcept { return *this; }
};
static_assert(!std::is_nothrow_move_assignable<optional<ThrowsMove>>::value, "");
struct ThrowsMoveAssign {
ThrowsMoveAssign() noexcept {}
ThrowsMoveAssign(ThrowsMoveAssign const&) noexcept {}
ThrowsMoveAssign(ThrowsMoveAssign &&) noexcept {}
ThrowsMoveAssign& operator=(ThrowsMoveAssign const&) noexcept { return *this; }
ThrowsMoveAssign& operator=(ThrowsMoveAssign &&) noexcept(false) { return *this; }
};
static_assert(!std::is_nothrow_move_assignable<optional<ThrowsMoveAssign>>::value, "");
struct NoThrowMove {
NoThrowMove() noexcept(false) {}
NoThrowMove(NoThrowMove const&) noexcept(false) {}
NoThrowMove(NoThrowMove &&) noexcept {}
NoThrowMove& operator=(NoThrowMove const&) noexcept { return *this; }
NoThrowMove& operator=(NoThrowMove&&) noexcept { return *this; }
};
static_assert(std::is_nothrow_move_assignable<optional<NoThrowMove>>::value, "");
}
return 0;
}