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-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 // <tuple>
10
11 // template <class... Types> class tuple;
12
13 // template <class U1, class U2>
14 // tuple& operator=(const pair<U1, U2>& u);
15
16 // UNSUPPORTED: c++03
17
18 #include <cassert>
19 #include <memory>
20 #include <tuple>
21 #include <type_traits>
22 #include <utility>
23
24 struct NothrowCopyAssignable {
25 NothrowCopyAssignable(NothrowCopyAssignable const&) = delete;
operator =NothrowCopyAssignable26 NothrowCopyAssignable& operator=(NothrowCopyAssignable const&) noexcept { return *this; }
27 };
28 struct PotentiallyThrowingCopyAssignable {
29 PotentiallyThrowingCopyAssignable(PotentiallyThrowingCopyAssignable const&) = delete;
operator =PotentiallyThrowingCopyAssignable30 PotentiallyThrowingCopyAssignable& operator=(PotentiallyThrowingCopyAssignable const&) { return *this; }
31 };
32
33 #include "test_macros.h"
34
35 TEST_CONSTEXPR_CXX20
test()36 bool test()
37 {
38 {
39 typedef std::pair<long, char> T0;
40 typedef std::tuple<long long, short> T1;
41 T0 t0(2, 'a');
42 T1 t1;
43 t1 = t0;
44 assert(std::get<0>(t1) == 2);
45 assert(std::get<1>(t1) == short('a'));
46 }
47 return true;
48 }
49
main(int,char **)50 int main(int, char**)
51 {
52 test();
53 #if TEST_STD_VER >= 20
54 static_assert(test());
55 #endif
56
57 {
58 // test that the implicitly generated copy assignment operator
59 // is properly deleted
60 using T = std::tuple<int, int>;
61 using P = std::tuple<std::unique_ptr<int>, std::unique_ptr<int>>;
62 static_assert(!std::is_assignable<T&, const P &>::value, "");
63 }
64 {
65 typedef std::tuple<NothrowCopyAssignable, long> Tuple;
66 typedef std::pair<NothrowCopyAssignable, int> Pair;
67 static_assert(std::is_nothrow_assignable<Tuple&, Pair const&>::value, "");
68 static_assert(std::is_nothrow_assignable<Tuple&, Pair&>::value, "");
69 static_assert(std::is_nothrow_assignable<Tuple&, Pair const&&>::value, "");
70 }
71 {
72 typedef std::tuple<PotentiallyThrowingCopyAssignable, long> Tuple;
73 typedef std::pair<PotentiallyThrowingCopyAssignable, int> Pair;
74 static_assert(std::is_assignable<Tuple&, Pair const&>::value, "");
75 static_assert(!std::is_nothrow_assignable<Tuple&, Pair const&>::value, "");
76
77 static_assert(std::is_assignable<Tuple&, Pair&>::value, "");
78 static_assert(!std::is_nothrow_assignable<Tuple&, Pair&>::value, "");
79
80 static_assert(std::is_assignable<Tuple&, Pair const&&>::value, "");
81 static_assert(!std::is_nothrow_assignable<Tuple&, Pair const&&>::value, "");
82 }
83
84 return 0;
85 }
86