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//===----------------------------------------------------------------------===//
// 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, c++17, c++20
// template<class G>
// constexpr explicit(!is_convertible_v<G, E>) expected(unexpected<G>&& e);
//
// Let GF be G
//
// Constraints: is_constructible_v<E, GF> is true.
//
// Effects: Direct-non-list-initializes unex with std::forward<GF>(e.error()).
//
// Postconditions: has_value() is false.
//
// Throws: Any exception thrown by the initialization of unex.
#include <cassert>
#include <expected>
#include <type_traits>
#include <utility>
#include "MoveOnly.h"
#include "test_macros.h"
// Test Constraints
static_assert(std::is_constructible_v<std::expected<int, int>, std::unexpected<int>>);
static_assert(std::is_constructible_v<std::expected<int, MoveOnly>, std::unexpected<MoveOnly>>);
// !is_constructible_v<E, GF>
struct foo {};
static_assert(!std::is_constructible_v<std::expected<int, int>, std::unexpected<foo>>);
// explicit(!is_convertible_v<G, E>)
struct NotConvertible {
explicit NotConvertible(int);
};
static_assert(std::is_convertible_v<std::unexpected<int>&&, std::expected<int, int>>);
static_assert(!std::is_convertible_v<std::unexpected<int>&&, std::expected<int, NotConvertible>>);
struct MyInt {
int i;
constexpr MyInt(int ii) : i(ii) {}
friend constexpr bool operator==(const MyInt&, const MyInt&) = default;
};
template <class Err>
constexpr void testInt() {
std::unexpected<int> u(5);
std::expected<int, Err> e(std::move(u));
assert(!e.has_value());
assert(e.error() == 5);
}
constexpr void testMoveOnly() {
std::unexpected<MoveOnly> u(MoveOnly(5));
std::expected<int, MoveOnly> e(std::move(u));
assert(!e.has_value());
assert(e.error() == 5);
assert(u.error() == 0);
}
constexpr bool test() {
testInt<int>();
testInt<MyInt>();
testInt<MoveOnly>();
testMoveOnly();
return true;
}
void testException() {
#ifndef TEST_HAS_NO_EXCEPTIONS
struct Except {};
struct Throwing {
Throwing(int) { throw Except{}; }
};
{
std::unexpected<int> u(5);
try {
[[maybe_unused]] std::expected<int, Throwing> e(std::move(u));
assert(false);
} catch (Except) {
}
}
#endif // TEST_HAS_NO_EXCEPTIONS
}
int main(int, char**) {
test();
static_assert(test());
testException();
return 0;
}
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