xref: /llvm-project/libcxx/test/std/strings/basic.string/string.cons/copy_assignment.pass.cpp (revision 786366b18fadc3d7c4f150e89ef49c165767a668)
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 // basic_string<charT,traits,Allocator>&
12 //   operator=(const basic_string<charT,traits,Allocator>& str); // constexpr since C++20
13 
14 #include <string>
15 #include <cassert>
16 
17 #include "test_macros.h"
18 #include "min_allocator.h"
19 
20 template <class S>
21 TEST_CONSTEXPR_CXX20 void
22 test(S s1, const S& s2)
23 {
24     s1 = s2;
25     LIBCPP_ASSERT(s1.__invariants());
26     assert(s1 == s2);
27     assert(s1.capacity() >= s1.size());
28 }
29 
30 template <class S>
31 TEST_CONSTEXPR_CXX20 void test_string() {
32   test(S(), S());
33   test(S("1"), S());
34   test(S(), S("1"));
35   test(S("1"), S("2"));
36   test(S("1"), S("2"));
37 
38   test(S(),
39         S("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
40   test(S("123456789"),
41         S("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
42   test(S("1234567890123456789012345678901234567890123456789012345678901234567890"),
43         S("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
44   test(S("1234567890123456789012345678901234567890123456789012345678901234567890"
45           "1234567890123456789012345678901234567890123456789012345678901234567890"),
46         S("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
47 }
48 
49 TEST_CONSTEXPR_CXX20 bool test() {
50   test_string<std::string>();
51 #if TEST_STD_VER >= 11
52   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
53 #endif
54 
55 #if TEST_STD_VER >= 11
56   {   // LWG 2946
57     std::string s;
58     s = {"abc", 1};
59     assert(s.size() == 1);
60     assert(s == "a");
61   }
62 #endif
63 
64   return true;
65 }
66 
67 int main(int, char**)
68 {
69   test();
70 #if TEST_STD_VER > 17
71   static_assert(test());
72 #endif
73 
74   return 0;
75 }
76