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 <iterator>
22 #include <limits>
23 
24 #include "test_macros.h"
25 
26 template<typename SV>
27 void test1 () {
28 #if TEST_STD_VER > 11
29     {
30     constexpr SV sv1;
31     static_assert ( sv1.size() == 0, "" );
32     static_assert ( sv1.empty(), "");
33     static_assert ( sv1.size() == sv1.length(), "" );
34     static_assert ( sv1.max_size() > sv1.size(), "");
35     }
36 #endif
37 
38     {
39     SV sv1;
40     ASSERT_NOEXCEPT(sv1.size());
41     ASSERT_NOEXCEPT(sv1.empty());
42     ASSERT_NOEXCEPT(sv1.max_size());
43     ASSERT_NOEXCEPT(sv1.length());
44     assert ( sv1.size() == 0 );
45     assert ( sv1.empty());
46     assert ( sv1.size() == sv1.length());
47     assert ( sv1.max_size() > sv1.size());
48     }
49 
50     // Sanity check max_size() -- a string_view can't store more bytes than a single object
51     // can contain. Any implementation that fails this check is certainly lying.
52     {
53         typedef typename SV::value_type CharT;
54         typedef typename SV::size_type Size;
55         SV sv;
56         assert(sv.max_size() <= std::numeric_limits<Size>::max() / sizeof(CharT));
57         LIBCPP_ASSERT(sv.max_size() == std::numeric_limits<Size>::max() / sizeof(CharT));
58     }
59 }
60 
61 template<typename CharT>
62 void test2 ( const CharT *s, size_t len ) {
63     {
64     std::basic_string_view<CharT> sv1 ( s );
65     assert ( sv1.size() == len );
66     assert ( sv1.data() == s );
67     assert ( sv1.empty() == (len == 0));
68     assert ( sv1.size() == sv1.length());
69     assert ( sv1.max_size() > sv1.size());
70 #if TEST_STD_VER > 14
71 //  make sure we pick up std::size, too!
72     assert ( sv1.size() == std::size(sv1));
73     assert ( sv1.empty() == std::empty(sv1));
74 #endif
75     }
76 }
77 
78 int main(int, char**) {
79     test1<std::string_view> ();
80 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
81     test1<std::u8string_view> ();
82 #endif
83     test1<std::u16string_view> ();
84     test1<std::u32string_view> ();
85 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
86     test1<std::wstring_view> ();
87 #endif
88 
89     test2 ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
90     test2 ( "ABCDE", 5 );
91     test2 ( "a", 1 );
92     test2 ( "", 0 );
93 
94 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
95     test2 ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
96     test2 ( L"ABCDE", 5 );
97     test2 ( L"a", 1 );
98     test2 ( L"", 0 );
99 #endif
100 
101 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
102     test2 ( u8"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
103     test2 ( u8"ABCDE", 5 );
104     test2 ( u8"a", 1 );
105     test2 ( u8"", 0 );
106 #endif
107 
108 #if TEST_STD_VER >= 11
109     test2 ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
110     test2 ( u"ABCDE", 5 );
111     test2 ( u"a", 1 );
112     test2 ( u"", 0 );
113 
114     test2 ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
115     test2 ( U"ABCDE", 5 );
116     test2 ( U"a", 1 );
117     test2 ( U"", 0 );
118 #endif
119 
120   return 0;
121 }
122