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 // [string.view.capacity], capacity
14 // constexpr size_type size()     const noexcept;
15 // constexpr size_type length()   const noexcept;
16 // constexpr size_type max_size() const noexcept;
17 // constexpr bool empty()         const noexcept;
18 
19 #include <string_view>
20 #include <cassert>
21 #include <limits>
22 
23 #include "test_macros.h"
24 
25 template<typename SV>
26 void test1 () {
27 #if TEST_STD_VER > 11
28     {
29     constexpr SV sv1;
30     static_assert ( sv1.size() == 0, "" );
31     static_assert ( sv1.empty(), "");
32     static_assert ( sv1.size() == sv1.length(), "" );
33     static_assert ( sv1.max_size() > sv1.size(), "");
34     }
35 #endif
36 
37     {
38     SV sv1;
39     ASSERT_NOEXCEPT(sv1.size());
40     ASSERT_NOEXCEPT(sv1.empty());
41     ASSERT_NOEXCEPT(sv1.max_size());
42     ASSERT_NOEXCEPT(sv1.length());
43     assert ( sv1.size() == 0 );
44     assert ( sv1.empty());
45     assert ( sv1.size() == sv1.length());
46     assert ( sv1.max_size() > sv1.size());
47     }
48 
49     // Sanity check max_size() -- a string_view can't store more bytes than a single object
50     // can contain. Any implementation that fails this check is certainly lying.
51     {
52         typedef typename SV::value_type CharT;
53         typedef typename SV::size_type Size;
54         SV sv;
55         assert(sv.max_size() <= std::numeric_limits<Size>::max() / sizeof(CharT));
56         LIBCPP_ASSERT(sv.max_size() == std::numeric_limits<Size>::max() / sizeof(CharT));
57     }
58 }
59 
60 template<typename CharT>
61 void test2 ( const CharT *s, size_t len ) {
62     {
63     std::basic_string_view<CharT> sv1 ( s );
64     assert ( sv1.size() == len );
65     assert ( sv1.data() == s );
66     assert ( sv1.empty() == (len == 0));
67     assert ( sv1.size() == sv1.length());
68     assert ( sv1.max_size() > sv1.size());
69 #if TEST_STD_VER > 14
70 //  make sure we pick up std::size, too!
71     assert ( sv1.size() == std::size(sv1));
72     assert ( sv1.empty() == std::empty(sv1));
73 #endif
74     }
75 }
76 
77 int main(int, char**) {
78     test1<std::string_view> ();
79 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
80     test1<std::u8string_view> ();
81 #endif
82     test1<std::u16string_view> ();
83     test1<std::u32string_view> ();
84 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
85     test1<std::wstring_view> ();
86 #endif
87 
88     test2 ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
89     test2 ( "ABCDE", 5 );
90     test2 ( "a", 1 );
91     test2 ( "", 0 );
92 
93 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
94     test2 ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
95     test2 ( L"ABCDE", 5 );
96     test2 ( L"a", 1 );
97     test2 ( L"", 0 );
98 #endif
99 
100 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
101     test2 ( u8"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
102     test2 ( u8"ABCDE", 5 );
103     test2 ( u8"a", 1 );
104     test2 ( u8"", 0 );
105 #endif
106 
107 #if TEST_STD_VER >= 11
108     test2 ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
109     test2 ( u"ABCDE", 5 );
110     test2 ( u"a", 1 );
111     test2 ( u"", 0 );
112 
113     test2 ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
114     test2 ( U"ABCDE", 5 );
115     test2 ( U"a", 1 );
116     test2 ( U"", 0 );
117 #endif
118 
119   return 0;
120 }
121