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 // UNSUPPORTED: c++03, c++11, c++14
10 
11 // <string_view>
12 
13 // Test that the constructors offered by std::basic_string_view are formulated
14 // so they're compatible with implicit deduction guides.
15 
16 #include <string_view>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "constexpr_char_traits.h"
21 
22 // Overloads
23 // ---------------
24 // (1)  basic_string_view() - NOT TESTED
25 // (2)  basic_string_view(const basic_string_view&)
26 // (3)  basic_string_view(const CharT*, size_type)
27 // (4)  basic_string_view(const CharT*)
main(int,char **)28 int main(int, char**) {
29   {
30     // Testing (1)
31     // Nothing to do. Cannot deduce without any arguments.
32   }
33   { // Testing (2)
34     const std::string_view sin("abc");
35     std::basic_string_view s(sin);
36     ASSERT_SAME_TYPE(decltype(s), std::string_view);
37     assert(s == "abc");
38 
39 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
40     using WSV = std::basic_string_view<wchar_t, constexpr_char_traits<wchar_t>>;
41     const WSV win(L"abcdef");
42     std::basic_string_view w(win);
43     ASSERT_SAME_TYPE(decltype(w), WSV);
44     assert(w == L"abcdef");
45 #endif
46   }
47   { // Testing (3)
48     std::basic_string_view s("abc", 2);
49     ASSERT_SAME_TYPE(decltype(s), std::string_view);
50     assert(s == "ab");
51 
52 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
53     std::basic_string_view w(L"abcdef", 4);
54     ASSERT_SAME_TYPE(decltype(w), std::wstring_view);
55     assert(w == L"abcd");
56 #endif
57   }
58   { // Testing (4)
59     std::basic_string_view s("abc");
60     ASSERT_SAME_TYPE(decltype(s), std::string_view);
61     assert(s == "abc");
62 
63 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
64     std::basic_string_view w(L"abcdef");
65     ASSERT_SAME_TYPE(decltype(w), std::wstring_view);
66     assert(w == L"abcdef");
67 #endif
68   }
69 
70   return 0;
71 }
72