85 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// <tuple>10 11// template <class... UTypes>12// constexpr const tuple& operator=(tuple<UTypes...>&& u) const;13//14// Constraints:15// - sizeof...(Types) equals sizeof...(UTypes) and16// - (is_assignable_v<const Types&, UTypes> && ...) is true.17 18// UNSUPPORTED: c++03, c++11, c++14, c++17, c++2019 20#include <cassert>21#include <tuple>22#include <type_traits>23 24#include "test_macros.h"25#include "copy_move_types.h"26 27// test constraints28 29// sizeof...(Types) equals sizeof...(UTypes)30static_assert(std::is_assignable_v<const std::tuple<int&>&, std::tuple<long&>&&>);31static_assert(!std::is_assignable_v<const std::tuple<int&, int&>&, std::tuple<long&>&&>);32static_assert(!std::is_assignable_v<const std::tuple<int&>&, std::tuple<long&, long&>&&>);33 34// (is_assignable_v<const Types&, UTypes&&> && ...) is true35static_assert(std::is_assignable_v<const std::tuple<AssignableFrom<ConstMoveAssign>>&, std::tuple<ConstMoveAssign>&&>);36 37static_assert(std::is_assignable_v<const std::tuple<AssignableFrom<ConstMoveAssign>, ConstMoveAssign>&,38 std::tuple<ConstMoveAssign, ConstMoveAssign>&&>);39 40static_assert(!std::is_assignable_v<const std::tuple<AssignableFrom<ConstMoveAssign>, AssignableFrom<MoveAssign>>&,41 std::tuple<ConstMoveAssign, MoveAssign>&&>);42 43constexpr bool test() {44 // reference types45 {46 int i1 = 1;47 int i2 = 2;48 long j1 = 3;49 long j2 = 4;50 std::tuple<int&, int&> t1{i1, i2};51 const std::tuple<long&, long&> t2{j1, j2};52 t2 = std::move(t1);53 assert(std::get<0>(t2) == 1);54 assert(std::get<1>(t2) == 2);55 }56 57 // user defined const copy assignment58 {59 std::tuple<ConstMoveAssign> t1{1};60 const std::tuple<AssignableFrom<ConstMoveAssign>> t2{2};61 t2 = std::move(t1);62 assert(std::get<0>(t2).v.val == 1);63 }64 65 // make sure the right assignment operator of the type in the tuple is used66 {67 std::tuple<TracedAssignment> t1{};68 const std::tuple<AssignableFrom<TracedAssignment>> t2{};69 t2 = std::move(t1);70 assert(std::get<0>(t2).v.constMoveAssign == 1);71 }72 73 return true;74}75 76int main(int, char**) {77 test();78 79// gcc cannot have mutable member in constant expression80#if !defined(TEST_COMPILER_GCC)81 static_assert(test());82#endif83 return 0;84}85