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// <string>
10
11// template<class _Tp>
12// basic_string(const _Tp& __t, size_type __pos, size_type __n,
13// const allocator_type& __a = allocator_type()); // constexpr since C++20
14//
15// Mostly we're testing string_view here
16
17#include <string>
18#include <string_view>
19#include <stdexcept>
20#include <algorithm>
21#include <cassert>
22
23#include "test_macros.h"
24#include "test_allocator.h"
25#include "min_allocator.h"
26#include "asan_testing.h"
27
28template <class S, class SV>
29TEST_CONSTEXPR_CXX20 void test(SV sv, std::size_t pos, std::size_t n) {
30 typedef typename S::traits_type T;
31 typedef typename S::allocator_type A;
32 typedef typename S::size_type Size;
33 if (pos <= sv.size()) {
34 S s2(sv, static_cast<Size>(pos), static_cast<Size>(n));
35 LIBCPP_ASSERT(s2.__invariants());
36 assert(pos <= sv.size());
37 std::size_t rlen = std::min(sv.size() - pos, n);
38 assert(s2.size() == rlen);
39 assert(T::compare(s2.data(), sv.data() + pos, rlen) == 0);
40 assert(s2.get_allocator() == A());
41 assert(s2.capacity() >= s2.size());
42 LIBCPP_ASSERT(is_string_asan_correct(s2));
43 }
44#ifndef TEST_HAS_NO_EXCEPTIONS
45 else if (!TEST_IS_CONSTANT_EVALUATED) {
46 try {
47 S s2(sv, static_cast<Size>(pos), static_cast<Size>(n));
48 assert(false);
49 } catch (std::out_of_range&) {
50 assert(pos > sv.size());
51 }
52 }
53#endif
54}
55
56template <class S, class SV>
57TEST_CONSTEXPR_CXX20 void test(SV sv, std::size_t pos, std::size_t n, const typename S::allocator_type& a) {
58 typedef typename S::traits_type T;
59 typedef typename S::size_type Size;
60 if (pos <= sv.size()) {
61 S s2(sv, static_cast<Size>(pos), static_cast<Size>(n), a);
62 LIBCPP_ASSERT(s2.__invariants());
63 assert(pos <= sv.size());
64 std::size_t rlen = std::min(sv.size() - pos, n);
65 assert(s2.size() == rlen);
66 assert(T::compare(s2.data(), sv.data() + pos, rlen) == 0);
67 assert(s2.get_allocator() == a);
68 assert(s2.capacity() >= s2.size());
69 }
70#ifndef TEST_HAS_NO_EXCEPTIONS
71 else if (!TEST_IS_CONSTANT_EVALUATED) {
72 try {
73 S s2(sv, static_cast<Size>(pos), static_cast<Size>(n), a);
74 assert(false);
75 } catch (std::out_of_range&) {
76 assert(pos > sv.size());
77 }
78 }
79#endif
80}
81
82template <class Alloc>
83TEST_CONSTEXPR_CXX20 void test_string(const Alloc& a) {
84 typedef std::basic_string_view<char, std::char_traits<char> > SV;
85 typedef std::basic_string<char, std::char_traits<char>, Alloc> S;
86
87 test<S, SV>(SV(), 0, 0);
88 test<S, SV>(SV(), 0, 1);
89 test<S, SV>(SV(), 1, 0);
90 test<S, SV>(SV(), 1, 1);
91 test<S, SV>(SV(), 1, 2);
92 test<S, SV>(SV("1"), 0, 0);
93 test<S, SV>(SV("1"), 0, 1);
94 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 0);
95 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 1);
96 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 10);
97 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 100);
98
99 test<S, SV>(SV(), 0, 0, Alloc(a));
100 test<S, SV>(SV(), 0, 1, Alloc(a));
101 test<S, SV>(SV(), 1, 0, Alloc(a));
102 test<S, SV>(SV(), 1, 1, Alloc(a));
103 test<S, SV>(SV(), 1, 2, Alloc(a));
104 test<S, SV>(SV("1"), 0, 0, Alloc(a));
105 test<S, SV>(SV("1"), 0, 1, Alloc(a));
106 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 0, Alloc(a));
107 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 1, Alloc(a));
108 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 10, Alloc(a));
109 test<S, SV>(SV("1234567890123456789012345678901234567890123456789012345678901234567890"), 50, 100, Alloc(a));
110}
111
112TEST_CONSTEXPR_CXX20 bool test() {
113 test_string(std::allocator<char>());
114 test_string(test_allocator<char>());
115 test_string(test_allocator<char>(8));
116#if TEST_STD_VER >= 11
117 test_string(min_allocator<char>());
118 test_string(safe_allocator<char>());
119#endif
120
121 {
122 typedef std::string S;
123 typedef std::string_view SV;
124 S s = "ABCD";
125 SV sv = "EFGH";
126 char arr[] = "IJKL";
127
128 S s1("CDEF", 4); // calls ctor(const char *, len)
129 assert(s1 == "CDEF");
130
131 S s2("QRST", 0, 3); // calls ctor(string("QRST", pos, len)
132 assert(s2 == "QRS");
133
134 S s3(sv, 0, std::string::npos); // calls ctor(T, pos, npos)
135 assert(s3 == sv);
136
137 S s4(sv, 0, 3); // calls ctor(T, pos, len)
138 assert(s4 == "EFG");
139
140 S s5(arr, 0, 2); // calls ctor(const char *, len)
141 assert(s5 == "IJ");
142
143 S s6(arr, 0); // calls ctor(const char *, len)
144 assert(s6 == "");
145
146 S s7(s.data(), 2); // calls ctor(const char *, len)
147 assert(s7 == "AB");
148 }
149
150 return true;
151}
152
153int main(int, char**) {
154 test();
155#if TEST_STD_VER > 17
156 static_assert(test());
157#endif
158
159 return 0;
160}
161

source code of libcxx/test/std/strings/basic.string/string.cons/T_size_size.pass.cpp