144 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++0310 11// <utility>12 13// template <class T1, class T2> struct pair14 15// template<class U = T1, class V = T2> pair(U&&, V&&);16 17#include <utility>18#include <cassert>19#include <memory>20 21#include "archetypes.h"22#include "test_convertible.h"23 24#include "test_macros.h"25using namespace ImplicitTypes; // Get implicitly archetypes26 27template <class T1, class T1Arg,28 bool CanCopy = true, bool CanConvert = CanCopy>29void test_sfinae() {30 using P1 = std::pair<T1, int>;31 using P2 = std::pair<int, T1>;32 using T2 = int const&;33 static_assert(std::is_constructible<P1, T1Arg, T2>::value == CanCopy, "");34 static_assert(test_convertible<P1, T1Arg, T2>() == CanConvert, "");35 static_assert(std::is_constructible<P2, T2, T1Arg>::value == CanCopy, "");36 static_assert(test_convertible<P2, T2, T1Arg>() == CanConvert, "");37}38 39struct ExplicitT {40 constexpr explicit ExplicitT(int x) : value(x) {}41 int value;42};43 44struct ImplicitT {45 constexpr ImplicitT(int x) : value(x) {}46 int value;47};48 49int main(int, char**)50{51 {52 typedef std::pair<std::unique_ptr<int>, short*> P;53 P p(std::unique_ptr<int>(new int(3)), nullptr);54 assert(*p.first == 3);55 assert(p.second == nullptr);56 }57 {58 // Test non-const lvalue and rvalue types59 test_sfinae<AllCtors, AllCtors&>();60 test_sfinae<AllCtors, AllCtors&&>();61 test_sfinae<ExplicitTypes::AllCtors, ExplicitTypes::AllCtors&, true, false>();62 test_sfinae<ExplicitTypes::AllCtors, ExplicitTypes::AllCtors&&, true, false>();63 test_sfinae<CopyOnly, CopyOnly&>();64 test_sfinae<CopyOnly, CopyOnly&&>();65 test_sfinae<ExplicitTypes::CopyOnly, ExplicitTypes::CopyOnly&, true, false>();66 test_sfinae<ExplicitTypes::CopyOnly, ExplicitTypes::CopyOnly&&, true, false>();67 test_sfinae<MoveOnly, MoveOnly&, false>();68 test_sfinae<MoveOnly, MoveOnly&&>();69 test_sfinae<ExplicitTypes::MoveOnly, ExplicitTypes::MoveOnly&, false>();70 test_sfinae<ExplicitTypes::MoveOnly, ExplicitTypes::MoveOnly&&, true, false>();71 test_sfinae<NonCopyable, NonCopyable&, false>();72 test_sfinae<NonCopyable, NonCopyable&&, false>();73 test_sfinae<ExplicitTypes::NonCopyable, ExplicitTypes::NonCopyable&, false>();74 test_sfinae<ExplicitTypes::NonCopyable, ExplicitTypes::NonCopyable&&, false>();75 }76 {77 // Test converting types78 test_sfinae<ConvertingType, int&>();79 test_sfinae<ConvertingType, const int&>();80 test_sfinae<ConvertingType, int&&>();81 test_sfinae<ConvertingType, const int&&>();82 test_sfinae<ExplicitTypes::ConvertingType, int&, true, false>();83 test_sfinae<ExplicitTypes::ConvertingType, const int&, true, false>();84 test_sfinae<ExplicitTypes::ConvertingType, int&&, true, false>();85 test_sfinae<ExplicitTypes::ConvertingType, const int&&, true, false>();86 }87#if TEST_STD_VER > 1188 { // explicit constexpr test89 constexpr std::pair<ExplicitT, ExplicitT> p(42, 43);90 static_assert(p.first.value == 42, "");91 static_assert(p.second.value == 43, "");92 }93 { // implicit constexpr test94 constexpr std::pair<ImplicitT, ImplicitT> p = {42, 43};95 static_assert(p.first.value == 42, "");96 static_assert(p.second.value == 43, "");97 }98#endif99 100 // Test support for http://wg21.link/P1951, default arguments for pair's constructor.101 // Basically, this turns copies for brace initialization into moves.102#if TEST_STD_VER > 20103 {104 struct TrackInit {105 TrackInit() = default;106 constexpr TrackInit(TrackInit const& other) : wasMoveInit(other.wasMoveInit), wasCopyInit(true) { }107 constexpr TrackInit(TrackInit&& other) : wasMoveInit(true), wasCopyInit(other.wasCopyInit) { }108 bool wasMoveInit = false;109 bool wasCopyInit = false;110 };111 112 // Explicit constructor113 {114 {115 std::pair<TrackInit, int> p({}, 3);116 assert( p.first.wasMoveInit);117 assert(!p.first.wasCopyInit);118 }119 {120 std::pair<int, TrackInit> p(3, {});121 assert( p.second.wasMoveInit);122 assert(!p.second.wasCopyInit);123 }124 }125 126 // Implicit constructor127 {128 {129 std::pair<TrackInit, int> p = {{}, 3};130 assert( p.first.wasMoveInit);131 assert(!p.first.wasCopyInit);132 }133 {134 std::pair<int, TrackInit> p = {3, {}};135 assert( p.second.wasMoveInit);136 assert(!p.second.wasCopyInit);137 }138 }139 }140#endif // TEST_STD_VER > 20141 142 return 0;143}144