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 // <string>
10 
11 // template<class charT, class traits, class Allocator>
12 //   void swap(basic_string<charT,traits,Allocator>& lhs,
13 //             basic_string<charT,traits,Allocator>& rhs); // constexpr since C++20
14 
15 #include <string>
16 #include <stdexcept>
17 #include <algorithm>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 #include "min_allocator.h"
22 
23 template <class S>
24 TEST_CONSTEXPR_CXX20 void
25 test(S s1, S s2)
26 {
27     S s1_ = s1;
28     S s2_ = s2;
29     swap(s1, s2);
30     LIBCPP_ASSERT(s1.__invariants());
31     LIBCPP_ASSERT(s2.__invariants());
32     assert(s1 == s2_);
33     assert(s2 == s1_);
34 }
35 
36 TEST_CONSTEXPR_CXX20 bool test() {
37   {
38     typedef std::string S;
39     test(S(""), S(""));
40     test(S(""), S("12345"));
41     test(S(""), S("1234567890"));
42     test(S(""), S("12345678901234567890"));
43     test(S("abcde"), S(""));
44     test(S("abcde"), S("12345"));
45     test(S("abcde"), S("1234567890"));
46     test(S("abcde"), S("12345678901234567890"));
47     test(S("abcdefghij"), S(""));
48     test(S("abcdefghij"), S("12345"));
49     test(S("abcdefghij"), S("1234567890"));
50     test(S("abcdefghij"), S("12345678901234567890"));
51     test(S("abcdefghijklmnopqrst"), S(""));
52     test(S("abcdefghijklmnopqrst"), S("12345"));
53     test(S("abcdefghijklmnopqrst"), S("1234567890"));
54     test(S("abcdefghijklmnopqrst"), S("12345678901234567890"));
55   }
56 #if TEST_STD_VER >= 11
57   {
58     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
59     test(S(""), S(""));
60     test(S(""), S("12345"));
61     test(S(""), S("1234567890"));
62     test(S(""), S("12345678901234567890"));
63     test(S("abcde"), S(""));
64     test(S("abcde"), S("12345"));
65     test(S("abcde"), S("1234567890"));
66     test(S("abcde"), S("12345678901234567890"));
67     test(S("abcdefghij"), S(""));
68     test(S("abcdefghij"), S("12345"));
69     test(S("abcdefghij"), S("1234567890"));
70     test(S("abcdefghij"), S("12345678901234567890"));
71     test(S("abcdefghijklmnopqrst"), S(""));
72     test(S("abcdefghijklmnopqrst"), S("12345"));
73     test(S("abcdefghijklmnopqrst"), S("1234567890"));
74     test(S("abcdefghijklmnopqrst"), S("12345678901234567890"));
75   }
76 #endif
77 
78   return true;
79 }
80 
81 int main(int, char**)
82 {
83   test();
84 #if TEST_STD_VER > 17
85   static_assert(test());
86 #endif
87 
88   return 0;
89 }
90