104 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++17, c++2010 11// constexpr expected(const expected& rhs);12//13// Effects: If rhs.has_value() is false, direct-non-list-initializes unex with rhs.error().14//15// Postconditions: rhs.has_value() == this->has_value().16//17// Throws: Any exception thrown by the initialization of unex.18//19// Remarks:20// - This constructor is defined as deleted unless is_copy_constructible_v<E> is true.21// - This constructor is trivial if is_trivially_copy_constructible_v<E> is true.22 23#include <cassert>24#include <expected>25#include <type_traits>26#include <utility>27 28#include "test_macros.h"29#include "../../types.h"30 31struct NonCopyable {32 NonCopyable(const NonCopyable&) = delete;33};34 35struct CopyableNonTrivial {36 int i;37 constexpr CopyableNonTrivial(int ii) : i(ii) {}38 constexpr CopyableNonTrivial(const CopyableNonTrivial& o) { i = o.i; }39 friend constexpr bool operator==(const CopyableNonTrivial&, const CopyableNonTrivial&) = default;40};41 42// Test: This constructor is defined as deleted unless is_copy_constructible_v<E> is true.43static_assert(std::is_copy_constructible_v<std::expected<void, int>>);44static_assert(std::is_copy_constructible_v<std::expected<void, CopyableNonTrivial>>);45static_assert(!std::is_copy_constructible_v<std::expected<void, NonCopyable>>);46 47// Test: This constructor is trivial if is_trivially_copy_constructible_v<E> is true.48static_assert(std::is_trivially_copy_constructible_v<std::expected<void, int>>);49static_assert(!std::is_trivially_copy_constructible_v<std::expected<void, CopyableNonTrivial>>);50 51constexpr bool test() {52 // copy the error non-trivial53 {54 const std::expected<void, CopyableNonTrivial> e1(std::unexpect, 5);55 auto e2 = e1;56 assert(!e2.has_value());57 assert(e2.error().i == 5);58 }59 60 // copy the error trivial61 {62 const std::expected<void, int> e1(std::unexpect, 5);63 auto e2 = e1;64 assert(!e2.has_value());65 assert(e2.error() == 5);66 }67 68 // copy TailClobberer as error69 {70 const std::expected<void, TailClobberer<1>> e1(std::unexpect);71 auto e2 = e1;72 assert(!e2.has_value());73 }74 75 return true;76}77 78void testException() {79#ifndef TEST_HAS_NO_EXCEPTIONS80 struct Throwing {81 Throwing() = default;82 Throwing(const Throwing&) { throw Except{}; }83 };84 85 // throw on copying error86 {87 const std::expected<void, Throwing> e1(std::unexpect);88 try {89 [[maybe_unused]] auto e2 = e1;90 assert(false);91 } catch (Except) {92 }93 }94 95#endif // TEST_HAS_NO_EXCEPTIONS96}97 98int main(int, char**) {99 test();100 static_assert(test());101 testException();102 return 0;103}104