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<> struct char_traits<char>
12 
13 // static int compare(const char_type* s1, const char_type* s2, size_t n);
14 // constexpr in C++17
15 
16 #include <string>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
21 #if TEST_STD_VER > 14
test_constexpr()22 constexpr bool test_constexpr()
23 {
24     return std::char_traits<char>::compare("123", "223", 3) < 0
25         && std::char_traits<char>::compare("223", "123", 3) > 0
26         && std::char_traits<char>::compare("123", "123", 3) == 0;
27 }
28 #endif
29 
main(int,char **)30 int main(int, char**)
31 {
32     assert(std::char_traits<char>::compare("", "", 0) == 0);
33     assert(std::char_traits<char>::compare(NULL, NULL, 0) == 0);
34 
35     assert(std::char_traits<char>::compare("1", "1", 1) == 0);
36     assert(std::char_traits<char>::compare("1", "2", 1) < 0);
37     assert(std::char_traits<char>::compare("2", "1", 1) > 0);
38 
39     assert(std::char_traits<char>::compare("12", "12", 2) == 0);
40     assert(std::char_traits<char>::compare("12", "13", 2) < 0);
41     assert(std::char_traits<char>::compare("12", "22", 2) < 0);
42     assert(std::char_traits<char>::compare("13", "12", 2) > 0);
43     assert(std::char_traits<char>::compare("22", "12", 2) > 0);
44 
45     assert(std::char_traits<char>::compare("123", "123", 3) == 0);
46     assert(std::char_traits<char>::compare("123", "223", 3) < 0);
47     assert(std::char_traits<char>::compare("123", "133", 3) < 0);
48     assert(std::char_traits<char>::compare("123", "124", 3) < 0);
49     assert(std::char_traits<char>::compare("223", "123", 3) > 0);
50     assert(std::char_traits<char>::compare("133", "123", 3) > 0);
51     assert(std::char_traits<char>::compare("124", "123", 3) > 0);
52 
53 #if TEST_STD_VER > 14
54     static_assert(test_constexpr(), "" );
55 #endif
56 
57   return 0;
58 }
59