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 // UNSUPPORTED: c++98, c++03
11
12 // <string>
13
14 // basic_string& operator=(basic_string&& c)
15 // noexcept(
16 // allocator_traits<allocator_type>::propagate_on_container_move_assignment::value ||
17 // allocator_traits<allocator_type>::is_always_equal::value); // C++17
18 //
19 // before C++17, we use the conforming extension
20 // noexcept(
21 // allocator_type::propagate_on_container_move_assignment::value &&
22 // is_nothrow_move_assignable<allocator_type>::value);
23
24 #include <string>
25 #include <cassert>
26
27 #include "test_macros.h"
28 #include "test_allocator.h"
29
30 template <class T>
31 struct some_alloc
32 {
33 typedef T value_type;
34 some_alloc(const some_alloc&);
35 T *allocate(size_t);
36 };
37
38 template <class T>
39 struct some_alloc2
40 {
41 typedef T value_type;
42
some_alloc2some_alloc243 some_alloc2() {}
44 some_alloc2(const some_alloc2&);
45 T *allocate(size_t);
deallocatesome_alloc246 void deallocate(void*, unsigned) {}
47
48 typedef std::false_type propagate_on_container_move_assignment;
49 typedef std::true_type is_always_equal;
50 };
51
52 template <class T>
53 struct some_alloc3
54 {
55 typedef T value_type;
56
some_alloc3some_alloc357 some_alloc3() {}
58 some_alloc3(const some_alloc3&);
59 T *allocate(size_t);
deallocatesome_alloc360 void deallocate(void*, unsigned) {}
61
62 typedef std::false_type propagate_on_container_move_assignment;
63 typedef std::false_type is_always_equal;
64 };
65
main()66 int main()
67 {
68 {
69 typedef std::string C;
70 static_assert(std::is_nothrow_move_assignable<C>::value, "");
71 }
72 {
73 typedef std::basic_string<char, std::char_traits<char>, test_allocator<char>> C;
74 static_assert(!std::is_nothrow_move_assignable<C>::value, "");
75 }
76 {
77 typedef std::basic_string<char, std::char_traits<char>, some_alloc<char>> C;
78 #if TEST_STD_VER > 14
79 // if the allocators are always equal, then the move assignment can be noexcept
80 static_assert( std::is_nothrow_move_assignable<C>::value, "");
81 #else
82 static_assert(!std::is_nothrow_move_assignable<C>::value, "");
83 #endif
84 }
85 #if TEST_STD_VER > 14
86 {
87 // POCMA is false, always equal
88 typedef std::basic_string<char, std::char_traits<char>, some_alloc2<char>> C;
89 static_assert( std::is_nothrow_move_assignable<C>::value, "");
90 }
91 {
92 // POCMA is false, not always equal
93 typedef std::basic_string<char, std::char_traits<char>, some_alloc3<char>> C;
94 static_assert(!std::is_nothrow_move_assignable<C>::value, "");
95 }
96 #endif
97 }
98