xref: /llvm-project/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer.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>& assign(const charT* s); // constexpr since C++20
12 
13 #include <string>
14 #include <stdexcept>
15 #include <cassert>
16 
17 #include "test_macros.h"
18 #include "min_allocator.h"
19 
20 template <class S>
21 TEST_CONSTEXPR_CXX20 void test(S s, const typename S::value_type* str, S expected) {
22   s.assign(str);
23   LIBCPP_ASSERT(s.__invariants());
24   assert(s == expected);
25 }
26 
27 template <class S>
28 TEST_CONSTEXPR_CXX20 void test_string() {
29   test(S(), "", S());
30   test(S(), "12345", S("12345"));
31   test(S(), "12345678901234567890", S("12345678901234567890"));
32 
33   test(S("12345"), "", S());
34   test(S("12345"), "12345", S("12345"));
35   test(S("12345"), "1234567890", S("1234567890"));
36 
37   test(S("12345678901234567890"), "", S());
38   test(S("12345678901234567890"), "12345", S("12345"));
39   test(S("12345678901234567890"), "12345678901234567890", S("12345678901234567890"));
40 }
41 
42 TEST_CONSTEXPR_CXX20 bool test() {
43   test_string<std::string>();
44 #if TEST_STD_VER >= 11
45   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
46 #endif
47 
48   { // test assignment to self
49     typedef std::string S;
50     S s_short = "123/";
51     S s_long  = "Lorem ipsum dolor sit amet, consectetur/";
52 
53     s_short.assign(s_short.c_str());
54     assert(s_short == "123/");
55     s_short.assign(s_short.c_str() + 2);
56     assert(s_short == "3/");
57 
58     s_long.assign(s_long.c_str() + 30);
59     assert(s_long == "nsectetur/");
60   }
61 
62   return true;
63 }
64 
65 int main(int, char**) {
66   test();
67 #if TEST_STD_VER > 17
68   static_assert(test());
69 #endif
70 
71   return 0;
72 }
73