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: !stdlib=libc++ && (c++03 || c++11 || c++14)
10 
11 // <string_view>
12 
13 // void swap(basic_string_view& _other) noexcept
14 
15 #include <string_view>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 
20 template<typename CharT>
21 void test ( const CharT *s, size_t len ) {
22     typedef std::basic_string_view<CharT> SV;
23     {
24     SV sv1(s);
25     SV sv2;
26 
27     assert ( sv1.size() == len );
28     assert ( sv1.data() == s );
29     assert ( sv2.size() == 0 );
30 
31     sv1.swap ( sv2 );
32     assert ( sv1.size() == 0 );
33     assert ( sv2.size() == len );
34     assert ( sv2.data() == s );
35     }
36 
37 }
38 
39 #if TEST_STD_VER > 11
40 constexpr size_t test_ce ( size_t n, size_t k ) {
41     typedef std::basic_string_view<char> SV;
42     SV sv1{ "ABCDEFGHIJKL", n };
43     SV sv2 { sv1.data(), k };
44     sv1.swap ( sv2 );
45     return sv1.size();
46 }
47 #endif
48 
49 
50 int main(int, char**) {
51     test ( "ABCDE", 5 );
52     test ( "a", 1 );
53     test ( "", 0 );
54 
55 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
56     test ( L"ABCDE", 5 );
57     test ( L"a", 1 );
58     test ( L"", 0 );
59 #endif
60 
61 #if TEST_STD_VER >= 11
62     test ( u"ABCDE", 5 );
63     test ( u"a", 1 );
64     test ( u"", 0 );
65 
66     test ( U"ABCDE", 5 );
67     test ( U"a", 1 );
68     test ( U"", 0 );
69 #endif
70 
71 #if TEST_STD_VER > 11
72     {
73     static_assert ( test_ce (2, 3) == 3, "" );
74     static_assert ( test_ce (5, 3) == 3, "" );
75     static_assert ( test_ce (0, 1) == 1, "" );
76     }
77 #endif
78 
79   return 0;
80 }
81