xref: /llvm-project/libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp (revision 6e1dcc9335116f650d68cdbed12bbb34a99b2d9b)
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 // explicit basic_string(basic_string_view<CharT, traits> sv, const Allocator& a = Allocator()); // constexpr since C++20
12 
13 #include <algorithm>
14 #include <cassert>
15 #include <stdexcept>
16 #include <string_view>
17 #include <string>
18 #include <type_traits>
19 
20 #include "min_allocator.h"
21 #include "test_allocator.h"
22 #include "test_macros.h"
23 
24 static_assert(!std::is_convertible<std::string_view, std::string const&>::value, "");
25 static_assert(!std::is_convertible<std::string_view, std::string>::value, "");
26 
27 template <class Alloc, class CharT>
28 TEST_CONSTEXPR_CXX20 void test(std::basic_string_view<CharT> sv) {
29   typedef std::basic_string<CharT, std::char_traits<CharT>, Alloc> S;
30   typedef typename S::traits_type T;
31   {
32     S s2(sv);
33     LIBCPP_ASSERT(s2.__invariants());
34     assert(s2.size() == sv.size());
35     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
36     assert(s2.get_allocator() == Alloc());
37     assert(s2.capacity() >= s2.size());
38   }
39   {
40     S s2;
41     s2 = sv;
42     LIBCPP_ASSERT(s2.__invariants());
43     assert(s2.size() == sv.size());
44     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
45     assert(s2.get_allocator() == Alloc());
46     assert(s2.capacity() >= s2.size());
47   }
48 }
49 
50 template <class Alloc, class CharT>
51 TEST_CONSTEXPR_CXX20 void test(std::basic_string_view<CharT> sv, const Alloc& a) {
52   typedef std::basic_string<CharT, std::char_traits<CharT>, Alloc> S;
53   typedef typename S::traits_type T;
54   {
55     S s2(sv, a);
56     LIBCPP_ASSERT(s2.__invariants());
57     assert(s2.size() == sv.size());
58     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
59     assert(s2.get_allocator() == a);
60     assert(s2.capacity() >= s2.size());
61   }
62   {
63     S s2(a);
64     s2 = sv;
65     LIBCPP_ASSERT(s2.__invariants());
66     assert(s2.size() == sv.size());
67     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
68     assert(s2.get_allocator() == a);
69     assert(s2.capacity() >= s2.size());
70   }
71 }
72 
73 template <class Alloc>
74 TEST_CONSTEXPR_CXX20 void test_string(const Alloc& a) {
75   typedef std::basic_string_view<char, std::char_traits<char> > SV;
76 
77   test<Alloc>(SV(""));
78   test<Alloc>(SV(""), Alloc(a));
79 
80   test<Alloc>(SV("1"));
81   test<Alloc>(SV("1"), Alloc(a));
82 
83   test<Alloc>(SV("1234567980"));
84   test<Alloc>(SV("1234567980"), Alloc(a));
85 
86   test<Alloc>(SV("123456798012345679801234567980123456798012345679801234567980"));
87   test<Alloc>(SV("123456798012345679801234567980123456798012345679801234567980"), Alloc(a));
88 }
89 
90 TEST_CONSTEXPR_CXX20 bool test() {
91   test_string(std::allocator<char>());
92   test_string(test_allocator<char>());
93   test_string(test_allocator<char>(2));
94 #if TEST_STD_VER >= 11
95   test_string(min_allocator<char>());
96 #endif
97 
98   return true;
99 }
100 
101 int main(int, char**) {
102   test();
103 #if TEST_STD_VER > 17
104   static_assert(test());
105 #endif
106 
107   return 0;
108 }
109