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_view>
10 
11 // void swap(basic_string_view& _other) noexcept
12 
13 #include <string_view>
14 #include <cassert>
15 
16 #include "test_macros.h"
17 
18 template<typename CharT>
19 void test ( const CharT *s, size_t len ) {
20     typedef std::basic_string_view<CharT> SV;
21     {
22     SV sv1(s);
23     SV sv2;
24 
25     assert ( sv1.size() == len );
26     assert ( sv1.data() == s );
27     assert ( sv2.size() == 0 );
28 
29     sv1.swap ( sv2 );
30     assert ( sv1.size() == 0 );
31     assert ( sv2.size() == len );
32     assert ( sv2.data() == s );
33     }
34 
35 }
36 
37 #if TEST_STD_VER > 11
38 constexpr size_t test_ce ( size_t n, size_t k ) {
39     typedef std::basic_string_view<char> SV;
40     SV sv1{ "ABCDEFGHIJKL", n };
41     SV sv2 { sv1.data(), k };
42     sv1.swap ( sv2 );
43     return sv1.size();
44 }
45 #endif
46 
47 
48 int main(int, char**) {
49     test ( "ABCDE", 5 );
50     test ( "a", 1 );
51     test ( "", 0 );
52 
53     test ( L"ABCDE", 5 );
54     test ( L"a", 1 );
55     test ( L"", 0 );
56 
57 #if TEST_STD_VER >= 11
58     test ( u"ABCDE", 5 );
59     test ( u"a", 1 );
60     test ( u"", 0 );
61 
62     test ( U"ABCDE", 5 );
63     test ( U"a", 1 );
64     test ( U"", 0 );
65 #endif
66 
67 #if TEST_STD_VER > 11
68     {
69     static_assert ( test_ce (2, 3) == 3, "" );
70     static_assert ( test_ce (5, 3) == 3, "" );
71     static_assert ( test_ce (0, 1) == 1, "" );
72     }
73 #endif
74 
75   return 0;
76 }
77