xref: /llvm-project/libcxx/test/std/strings/basic.string/string.cons/char_assignment.pass.cpp (revision a40bada91aeda276a772acfbcae6e8de26755a11)
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>& operator=(charT c); // constexpr since C++20
12 
13 #include <string>
14 #include <cassert>
15 
16 #include "test_macros.h"
17 #include "min_allocator.h"
18 
19 template <class S>
20 TEST_CONSTEXPR_CXX20 void test(S s1, typename S::value_type s2) {
21   typedef typename S::traits_type T;
22   s1 = s2;
23   LIBCPP_ASSERT(s1.__invariants());
24   assert(s1.size() == 1);
25   assert(T::eq(s1[0], s2));
26   assert(s1.capacity() >= s1.size());
27 }
28 
29 template <class S>
30 TEST_CONSTEXPR_CXX20 void test_string() {
31   test(S(), 'a');
32   test(S("1"), 'a');
33   test(S("123456789"), 'a');
34   test(S("1234567890123456789012345678901234567890123456789012345678901234567890"), 'a');
35 }
36 
37 TEST_CONSTEXPR_CXX20 bool test() {
38   test_string<std::string>();
39 #if TEST_STD_VER >= 11
40   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
41 #endif
42 
43   return true;
44 }
45 
46 int main(int, char**) {
47   test();
48 #if TEST_STD_VER > 17
49   static_assert(test());
50 #endif
51 
52   return 0;
53 }
54