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 remove_suffix(size_type _n)
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     assert ( sv1.size() == len );
26     assert ( sv1.data() == s );
27 
28     if ( len > 0 ) {
29         sv1.remove_suffix ( 1 );
30         assert ( sv1.size() == (len - 1));
31         assert ( sv1.data() == s);
32         sv1.remove_suffix ( len - 1 );
33         }
34 
35     assert ( sv1.size() == 0 );
36     sv1.remove_suffix ( 0 );
37     assert ( sv1.size() == 0 );
38     }
39 
40 }
41 
42 #if TEST_STD_VER > 11
43 constexpr size_t test_ce ( size_t n, size_t k ) {
44     typedef std::basic_string_view<char> SV;
45     SV sv1{ "ABCDEFGHIJKL", n };
46     sv1.remove_suffix ( k );
47     return sv1.size();
48 }
49 #endif
50 
51 int main(int, char**) {
52     test ( "ABCDE", 5 );
53     test ( "a", 1 );
54     test ( "", 0 );
55 
56 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
57     test ( L"ABCDE", 5 );
58     test ( L"a", 1 );
59     test ( L"", 0 );
60 #endif
61 
62 #if TEST_STD_VER >= 11
63     test ( u"ABCDE", 5 );
64     test ( u"a", 1 );
65     test ( u"", 0 );
66 
67     test ( U"ABCDE", 5 );
68     test ( U"a", 1 );
69     test ( U"", 0 );
70 #endif
71 
72 #if TEST_STD_VER > 11
73     {
74     static_assert ( test_ce ( 5, 0 ) == 5, "" );
75     static_assert ( test_ce ( 5, 1 ) == 4, "" );
76     static_assert ( test_ce ( 5, 5 ) == 0, "" );
77     static_assert ( test_ce ( 9, 3 ) == 6, "" );
78     }
79 #endif
80 
81   return 0;
82 }
83