1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <string_view>
11
12// constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const;
13
14// Throws: out_of_range if pos > size().
15// Effects: Determines the effective length rlen of the string to reference as the smaller of n and size() - pos.
16// Returns: basic_string_view(data()+pos, rlen).
17
18#include <string_view>
19#include <algorithm>
20#include <stdexcept>
21#include <cassert>
22
23#include "test_macros.h"
24
25template<typename CharT>
26void test1(std::basic_string_view<CharT> sv, size_t n, size_t pos) {
27    std::basic_string_view<CharT> sv1;
28#ifdef TEST_HAS_NO_EXCEPTIONS
29    if (pos > sv.size())
30        return ;  // would throw if exceptions were enabled
31    sv1 = sv.substr(pos, n);
32#else
33    try {
34        sv1 = sv.substr(pos, n);
35        assert(pos <= sv.size());
36    }
37    catch (const std::out_of_range&) {
38        assert(pos > sv.size());
39        return ;
40    }
41#endif
42    const size_t rlen = std::min(n, sv.size() - pos);
43    assert (sv1.size() == rlen);
44    for (size_t i = 0; i < rlen; ++i)
45        assert(sv[pos+i] == sv1[i]);
46}
47
48
49template<typename CharT>
50void test ( const CharT *s ) {
51    typedef std::basic_string_view<CharT> string_view_t;
52
53    string_view_t sv1 ( s );
54
55    test1(sv1,  0, 0);
56    test1(sv1,  1, 0);
57    test1(sv1, 20, 0);
58    test1(sv1, sv1.size(), 0);
59
60    test1(sv1,   0, 3);
61    test1(sv1,   2, 3);
62    test1(sv1, 100, 3);
63
64    test1(sv1, 0, string_view_t::npos);
65    test1(sv1, 2, string_view_t::npos);
66    test1(sv1, sv1.size(), string_view_t::npos);
67
68    test1(sv1, sv1.size() + 1, 0);
69    test1(sv1, sv1.size() + 1, 1);
70    test1(sv1, sv1.size() + 1, string_view_t::npos);
71}
72
73int main () {
74    test ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
75    test ( "ABCDE");
76    test ( "a" );
77    test ( "" );
78
79    test ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
80    test ( L"ABCDE" );
81    test ( L"a" );
82    test ( L"" );
83
84#if TEST_STD_VER >= 11
85    test ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
86    test ( u"ABCDE" );
87    test ( u"a" );
88    test ( u"" );
89
90    test ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
91    test ( U"ABCDE" );
92    test ( U"a" );
93    test ( U"" );
94#endif
95
96#if TEST_STD_VER > 11
97    {
98    constexpr std::string_view sv1 { "ABCDE", 5 };
99
100    {
101    constexpr std::string_view sv2 = sv1.substr ( 0, 3 );
102    static_assert ( sv2.size() == 3, "" );
103    static_assert ( sv2[0] == 'A', "" );
104    static_assert ( sv2[1] == 'B', "" );
105    static_assert ( sv2[2] == 'C', "" );
106    }
107
108    {
109    constexpr std::string_view sv2 = sv1.substr ( 3, 0 );
110    static_assert ( sv2.size() == 0, "" );
111    }
112
113    {
114    constexpr std::string_view sv2 = sv1.substr ( 3, 3 );
115    static_assert ( sv2.size() == 2, "" );
116    static_assert ( sv2[0] == 'D', "" );
117    static_assert ( sv2[1] == 'E', "" );
118    }
119    }
120#endif
121}
122