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 //   basic_string<charT,traits,Allocator>
13 //   operator+(const basic_string<charT,traits,Allocator>& lhs, const charT* rhs); // constexpr since C++20
14 
15 // template<class charT, class traits, class Allocator>
16 //   basic_string<charT,traits,Allocator>&&
17 //   operator+(basic_string<charT,traits,Allocator>&& lhs, const charT* rhs); // constexpr since C++20
18 
19 #include <string>
20 #include <utility>
21 #include <cassert>
22 
23 #include "test_macros.h"
24 #include "min_allocator.h"
25 
26 template <class S>
27 TEST_CONSTEXPR_CXX20 void test0(const S& lhs, const typename S::value_type* rhs, const S& x) {
28   assert(lhs + rhs == x);
29 }
30 
31 #if TEST_STD_VER >= 11
32 template <class S>
33 TEST_CONSTEXPR_CXX20 void test1(S&& lhs, const typename S::value_type* rhs, const S& x) {
34   assert(std::move(lhs) + rhs == x);
35 }
36 #endif
37 
38 template <class S>
39 TEST_CONSTEXPR_CXX20 void test_string() {
40   test0(S(""), "", S(""));
41   test0(S(""), "12345", S("12345"));
42   test0(S(""), "1234567890", S("1234567890"));
43   test0(S(""), "12345678901234567890", S("12345678901234567890"));
44   test0(S("abcde"), "", S("abcde"));
45   test0(S("abcde"), "12345", S("abcde12345"));
46   test0(S("abcde"), "1234567890", S("abcde1234567890"));
47   test0(S("abcde"), "12345678901234567890", S("abcde12345678901234567890"));
48   test0(S("abcdefghij"), "", S("abcdefghij"));
49   test0(S("abcdefghij"), "12345", S("abcdefghij12345"));
50   test0(S("abcdefghij"), "1234567890", S("abcdefghij1234567890"));
51   test0(S("abcdefghij"), "12345678901234567890", S("abcdefghij12345678901234567890"));
52   test0(S("abcdefghijklmnopqrst"), "", S("abcdefghijklmnopqrst"));
53   test0(S("abcdefghijklmnopqrst"), "12345", S("abcdefghijklmnopqrst12345"));
54   test0(S("abcdefghijklmnopqrst"), "1234567890", S("abcdefghijklmnopqrst1234567890"));
55   test0(S("abcdefghijklmnopqrst"), "12345678901234567890", S("abcdefghijklmnopqrst12345678901234567890"));
56 #if TEST_STD_VER >= 11
57   test1(S(""), "", S(""));
58   test1(S(""), "12345", S("12345"));
59   test1(S(""), "1234567890", S("1234567890"));
60   test1(S(""), "12345678901234567890", S("12345678901234567890"));
61   test1(S("abcde"), "", S("abcde"));
62   test1(S("abcde"), "12345", S("abcde12345"));
63   test1(S("abcde"), "1234567890", S("abcde1234567890"));
64   test1(S("abcde"), "12345678901234567890", S("abcde12345678901234567890"));
65   test1(S("abcdefghij"), "", S("abcdefghij"));
66   test1(S("abcdefghij"), "12345", S("abcdefghij12345"));
67   test1(S("abcdefghij"), "1234567890", S("abcdefghij1234567890"));
68   test1(S("abcdefghij"), "12345678901234567890", S("abcdefghij12345678901234567890"));
69   test1(S("abcdefghijklmnopqrst"), "", S("abcdefghijklmnopqrst"));
70   test1(S("abcdefghijklmnopqrst"), "12345", S("abcdefghijklmnopqrst12345"));
71   test1(S("abcdefghijklmnopqrst"), "1234567890", S("abcdefghijklmnopqrst1234567890"));
72   test1(S("abcdefghijklmnopqrst"), "12345678901234567890", S("abcdefghijklmnopqrst12345678901234567890"));
73 #endif
74 }
75 
76 TEST_CONSTEXPR_CXX20 bool test() {
77   test_string<std::string>();
78 #if TEST_STD_VER >= 11
79   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char> > >();
80 #endif
81 
82   return true;
83 }
84 
85 int main(int, char**) {
86   test();
87 #if TEST_STD_VER > 17
88   static_assert(test());
89 #endif
90 
91   return 0;
92 }
93