xref: /llvm-project/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.pass.cpp (revision f75f171b2050660a76d1458bf967a748770d54cc)
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 // UNSUPPORTED: c++03, c++11, c++14
11 
12 // template<class InputIterator>
13 //   basic_string(InputIterator begin, InputIterator end,
14 //   const Allocator& a = Allocator());
15 
16 // template<class InputIterator,
17 //      class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
18 //  basic_string(InputIterator, InputIterator, Allocator = Allocator())
19 //    -> basic_string<typename iterator_traits<InputIterator>::value_type,
20 //                 char_traits<typename iterator_traits<InputIterator>::value_type>,
21 //                 Allocator>;
22 //
23 //  The deduction guide shall not participate in overload resolution if InputIterator
24 //  is a type that does not qualify as an input iterator, or if Allocator is a type
25 //  that does not qualify as an allocator.
26 
27 #include <string>
28 #include <iterator>
29 #include <cassert>
30 #include <cstddef>
31 
32 #include "test_macros.h"
33 #include "test_allocator.h"
34 #include "min_allocator.h"
35 
36 bool test() {
37   {
38     const char* s = "12345678901234";
39     std::basic_string s1(s, s+10);  // Can't use {} here
40     using S = decltype(s1); // what type did we get?
41     static_assert(std::is_same_v<S::value_type,                      char>,  "");
42     static_assert(std::is_same_v<S::traits_type,    std::char_traits<char>>, "");
43     static_assert(std::is_same_v<S::allocator_type,   std::allocator<char>>, "");
44     assert(s1.size() == 10);
45     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
46   }
47   {
48     const char* s = "12345678901234";
49     std::basic_string s1{s, s+10, std::allocator<char>{}};
50     using S = decltype(s1); // what type did we get?
51     static_assert(std::is_same_v<S::value_type,                      char>,  "");
52     static_assert(std::is_same_v<S::traits_type,    std::char_traits<char>>, "");
53     static_assert(std::is_same_v<S::allocator_type,   std::allocator<char>>, "");
54     assert(s1.size() == 10);
55     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
56   }
57   {
58     const wchar_t* s = L"12345678901234";
59     std::basic_string s1{s, s+10, test_allocator<wchar_t>{}};
60     using S = decltype(s1); // what type did we get?
61     static_assert(std::is_same_v<S::value_type,                      wchar_t>,  "");
62     static_assert(std::is_same_v<S::traits_type,    std::char_traits<wchar_t>>, "");
63     static_assert(std::is_same_v<S::allocator_type,   test_allocator<wchar_t>>, "");
64     assert(s1.size() == 10);
65     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
66   }
67   {
68     const char16_t* s = u"12345678901234";
69     std::basic_string s1{s, s+10, min_allocator<char16_t>{}};
70     using S = decltype(s1); // what type did we get?
71     static_assert(std::is_same_v<S::value_type,                      char16_t>,  "");
72     static_assert(std::is_same_v<S::traits_type,    std::char_traits<char16_t>>, "");
73     static_assert(std::is_same_v<S::allocator_type,    min_allocator<char16_t>>, "");
74     assert(s1.size() == 10);
75     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
76   }
77   {
78     const char32_t* s = U"12345678901234";
79     std::basic_string s1{s, s+10, explicit_allocator<char32_t>{}};
80     using S = decltype(s1); // what type did we get?
81     static_assert(std::is_same_v<S::value_type,                        char32_t>,  "");
82     static_assert(std::is_same_v<S::traits_type,      std::char_traits<char32_t>>, "");
83     static_assert(std::is_same_v<S::allocator_type, explicit_allocator<char32_t>>, "");
84     assert(s1.size() == 10);
85     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
86   }
87 
88   return true;
89 }
90 
91 int main(int, char**)
92 {
93 
94   return 0;
95 }
96