1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 // <tuple>
11
12 // template <class... Types> class tuple;
13
14 // tuple& operator=(tuple&& u);
15
16 // UNSUPPORTED: c++98, c++03
17
18 #include <tuple>
19 #include <utility>
20 #include <cassert>
21
22 #include "MoveOnly.h"
23
24 struct NonAssignable {
25 NonAssignable& operator=(NonAssignable const&) = delete;
26 NonAssignable& operator=(NonAssignable&&) = delete;
27 };
28 struct CopyAssignable {
29 CopyAssignable& operator=(CopyAssignable const&) = default;
30 CopyAssignable& operator=(CopyAssignable&&) = delete;
31 };
32 static_assert(std::is_copy_assignable<CopyAssignable>::value, "");
33 struct MoveAssignable {
34 MoveAssignable& operator=(MoveAssignable const&) = delete;
35 MoveAssignable& operator=(MoveAssignable&&) = default;
36 };
37
38
39 struct CountAssign {
40 static int copied;
41 static int moved;
resetCountAssign42 static void reset() { copied = moved = 0; }
43 CountAssign() = default;
operator =CountAssign44 CountAssign& operator=(CountAssign const&) { ++copied; return *this; }
operator =CountAssign45 CountAssign& operator=(CountAssign&&) { ++moved; return *this; }
46 };
47 int CountAssign::copied = 0;
48 int CountAssign::moved = 0;
49
50
main()51 int main()
52 {
53 {
54 typedef std::tuple<> T;
55 T t0;
56 T t;
57 t = std::move(t0);
58 }
59 {
60 typedef std::tuple<MoveOnly> T;
61 T t0(MoveOnly(0));
62 T t;
63 t = std::move(t0);
64 assert(std::get<0>(t) == 0);
65 }
66 {
67 typedef std::tuple<MoveOnly, MoveOnly> T;
68 T t0(MoveOnly(0), MoveOnly(1));
69 T t;
70 t = std::move(t0);
71 assert(std::get<0>(t) == 0);
72 assert(std::get<1>(t) == 1);
73 }
74 {
75 typedef std::tuple<MoveOnly, MoveOnly, MoveOnly> T;
76 T t0(MoveOnly(0), MoveOnly(1), MoveOnly(2));
77 T t;
78 t = std::move(t0);
79 assert(std::get<0>(t) == 0);
80 assert(std::get<1>(t) == 1);
81 assert(std::get<2>(t) == 2);
82 }
83 {
84 // test reference assignment.
85 using T = std::tuple<int&, int&&>;
86 int x = 42;
87 int y = 100;
88 int x2 = -1;
89 int y2 = 500;
90 T t(x, std::move(y));
91 T t2(x2, std::move(y2));
92 t = std::move(t2);
93 assert(std::get<0>(t) == x2);
94 assert(&std::get<0>(t) == &x);
95 assert(std::get<1>(t) == y2);
96 assert(&std::get<1>(t) == &y);
97 }
98 {
99 // test that the implicitly generated move assignment operator
100 // is properly deleted
101 using T = std::tuple<std::unique_ptr<int>>;
102 static_assert(std::is_move_assignable<T>::value, "");
103 static_assert(!std::is_copy_assignable<T>::value, "");
104
105 }
106 {
107 using T = std::tuple<int, NonAssignable>;
108 static_assert(!std::is_move_assignable<T>::value, "");
109 }
110 {
111 using T = std::tuple<int, MoveAssignable>;
112 static_assert(std::is_move_assignable<T>::value, "");
113 }
114 {
115 // The move should decay to a copy.
116 CountAssign::reset();
117 using T = std::tuple<CountAssign, CopyAssignable>;
118 static_assert(std::is_move_assignable<T>::value, "");
119 T t1;
120 T t2;
121 t1 = std::move(t2);
122 assert(CountAssign::copied == 1);
123 assert(CountAssign::moved == 0);
124 }
125 }
126