xref: /llvm-project/libcxx/test/std/strings/string.view/string.view.ops/copy.pass.cpp (revision e99c4906e44ae3f921fa05356909d006cda8d954)
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 // size_type copy(charT* s, size_type n, size_type pos = 0) const;
14 
15 // Throws: out_of_range if pos > size().
16 // Remarks: Let rlen be the smaller of n and size() - pos.
17 // Requires: [s, s+rlen) is a valid range.
18 // Effects: Equivalent to std::copy_n(begin() + pos, rlen, s).
19 // Returns: rlen.
20 
21 #include <algorithm>
22 #include <cassert>
23 #include <cstddef>
24 #include <stdexcept>
25 #include <string_view>
26 
27 #include "test_macros.h"
28 
29 template <typename CharT>
30 void test1(std::basic_string_view<CharT> sv, std::size_t n, size_t pos) {
31   const std::size_t rlen = std::min(n, sv.size() - pos);
32 
33   CharT* dest1 = new CharT[rlen + 1];
34   dest1[rlen]  = 0;
35   CharT* dest2 = new CharT[rlen + 1];
36   dest2[rlen]  = 0;
37 
38   if (pos > sv.size()) {
39 #ifndef TEST_HAS_NO_EXCEPTIONS
40     try {
41       sv.copy(dest1, n, pos);
42       assert(false);
43     } catch (const std::out_of_range&) {
44     } catch (...) {
45       assert(false);
46     }
47 #endif
48   } else {
49     sv.copy(dest1, n, pos);
50     std::copy_n(sv.begin() + pos, rlen, dest2);
51     for (std::size_t i = 0; i <= rlen; ++i)
52       assert(dest1[i] == dest2[i]);
53   }
54   delete[] dest1;
55   delete[] dest2;
56 }
57 
58 template <typename CharT>
59 void test(const CharT* s) {
60   typedef std::basic_string_view<CharT> string_view_t;
61 
62   string_view_t sv1(s);
63 
64   test1(sv1, 0, 0);
65   test1(sv1, 1, 0);
66   test1(sv1, 20, 0);
67   test1(sv1, sv1.size(), 0);
68   test1(sv1, 20, string_view_t::npos);
69 
70   test1(sv1, 0, 3);
71   test1(sv1, 2, 3);
72   test1(sv1, 100, 3);
73   test1(sv1, 100, string_view_t::npos);
74 
75   test1(sv1, sv1.size(), string_view_t::npos);
76 
77   test1(sv1, sv1.size() + 1, 0);
78   test1(sv1, sv1.size() + 1, 1);
79   test1(sv1, sv1.size() + 1, string_view_t::npos);
80 }
81 
82 template <typename CharT>
83 TEST_CONSTEXPR_CXX20 bool test_constexpr_copy(const CharT* abcde, const CharT* ghijk, const CharT* bcdjk) {
84   CharT buf[6] = {};
85   std::basic_string_view<CharT> lval(ghijk);
86   lval.copy(buf, 6);
87   std::basic_string_view<CharT>(abcde).copy(buf, 3, 1);
88   assert(std::basic_string_view<CharT>(buf) == bcdjk);
89   return true;
90 }
91 
92 int main(int, char**) {
93   test("ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE");
94   test("ABCDE");
95   test("a");
96   test("");
97 
98 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
99   test(L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE");
100   test(L"ABCDE");
101   test(L"a");
102   test(L"");
103 #endif
104 
105 #if TEST_STD_VER >= 11
106   test(u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE");
107   test(u"ABCDE");
108   test(u"a");
109   test(u"");
110 
111   test(U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE");
112   test(U"ABCDE");
113   test(U"a");
114   test(U"");
115 #endif
116 
117   test_constexpr_copy("ABCDE", "GHIJK", "BCDJK");
118 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
119   test_constexpr_copy(L"ABCDE", L"GHIJK", L"BCDJK");
120 #endif
121 #if TEST_STD_VER >= 11
122   test_constexpr_copy(u"ABCDE", u"GHIJK", u"BCDJK");
123   test_constexpr_copy(U"ABCDE", U"GHIJK", U"BCDJK");
124 #endif
125 #if TEST_STD_VER >= 17
126   test_constexpr_copy(u8"ABCDE", u8"GHIJK", u8"BCDJK");
127 #endif
128 #if TEST_STD_VER >= 20
129   static_assert(test_constexpr_copy("ABCDE", "GHIJK", "BCDJK"));
130 #  ifndef TEST_HAS_NO_WIDE_CHARACTERS
131   static_assert(test_constexpr_copy(L"ABCDE", L"GHIJK", L"BCDJK"));
132 #  endif
133   static_assert(test_constexpr_copy(u"ABCDE", u"GHIJK", u"BCDJK"));
134   static_assert(test_constexpr_copy(U"ABCDE", U"GHIJK", U"BCDJK"));
135   static_assert(test_constexpr_copy(u8"ABCDE", u8"GHIJK", u8"BCDJK"));
136 #endif
137 
138   return 0;
139 }
140