xref: /llvm-project/libcxx/test/std/ranges/range.factories/range.istream.view/iterator/increment.pass.cpp (revision 96a509bca28b8668c3c2c68aae4116cc0d8c2952)
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: no-localization
10 // UNSUPPORTED: c++03, c++11, c++14, c++17
11 
12 // iterator& operator++();
13 // void operator++(int);
14 
15 #include <cassert>
16 #include <ranges>
17 #include <sstream>
18 
19 #include "test_macros.h"
20 #include "../utils.h"
21 
22 template <class CharT>
test()23 void test() {
24   // operator ++()
25   {
26     auto iss = make_string_stream<CharT>("1 2 345 ");
27     std::ranges::basic_istream_view<int, CharT> isv{iss};
28     auto it = isv.begin();
29     assert(*it == 1);
30 
31     std::same_as<decltype(it)&> decltype(auto) it2 = ++it;
32     assert(&it2 == &it);
33     assert(*it2 == 2);
34 
35     ++it2;
36     assert(*it2 == 345);
37 
38     ++it2;
39     assert(it2 == isv.end());
40   }
41 
42   // operator ++(int)
43   {
44     auto iss = make_string_stream<CharT>("1 2 345 ");
45     std::ranges::basic_istream_view<int, CharT> isv{iss};
46     auto it = isv.begin();
47     assert(*it == 1);
48 
49     static_assert(std::same_as<decltype(it++), void>);
50     it++;
51     assert(*it == 2);
52   }
53 }
54 
main(int,char **)55 int main(int, char**) {
56   test<char>();
57 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
58   test<wchar_t>();
59 #endif
60 
61   return 0;
62 }
63