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<char16_t>
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   return std::char_traits<char16_t>::compare(u"123", u"223", 3) < 0 &&
24          std::char_traits<char16_t>::compare(u"223", u"123", 3) > 0 &&
25          std::char_traits<char16_t>::compare(u"123", u"123", 3) == 0;
26 }
27 #endif
28 
main(int,char **)29 int main(int, char**) {
30 #if TEST_STD_VER >= 11
31   assert(std::char_traits<char16_t>::compare(u"", u"", 0) == 0);
32   assert(std::char_traits<char16_t>::compare(NULL, NULL, 0) == 0);
33 
34   assert(std::char_traits<char16_t>::compare(u"1", u"1", 1) == 0);
35   assert(std::char_traits<char16_t>::compare(u"1", u"2", 1) < 0);
36   assert(std::char_traits<char16_t>::compare(u"2", u"1", 1) > 0);
37 
38   assert(std::char_traits<char16_t>::compare(u"12", u"12", 2) == 0);
39   assert(std::char_traits<char16_t>::compare(u"12", u"13", 2) < 0);
40   assert(std::char_traits<char16_t>::compare(u"12", u"22", 2) < 0);
41   assert(std::char_traits<char16_t>::compare(u"13", u"12", 2) > 0);
42   assert(std::char_traits<char16_t>::compare(u"22", u"12", 2) > 0);
43 
44   assert(std::char_traits<char16_t>::compare(u"123", u"123", 3) == 0);
45   assert(std::char_traits<char16_t>::compare(u"123", u"223", 3) < 0);
46   assert(std::char_traits<char16_t>::compare(u"123", u"133", 3) < 0);
47   assert(std::char_traits<char16_t>::compare(u"123", u"124", 3) < 0);
48   assert(std::char_traits<char16_t>::compare(u"223", u"123", 3) > 0);
49   assert(std::char_traits<char16_t>::compare(u"133", u"123", 3) > 0);
50   assert(std::char_traits<char16_t>::compare(u"124", u"123", 3) > 0);
51 #endif
52 
53 #if TEST_STD_VER > 14
54   static_assert(test_constexpr(), "");
55 #endif
56 
57   return 0;
58 }
59