libcxx/test/std/ranges/range.factories/range.istream.view/iterator/deref.pass.cpp

   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 // Val& operator*() const;
  13
  14 #include <cassert>
  15 #include <ranges>
  16 #include <sstream>
  17
  18 #include "test_macros.h"
  19 #include "../utils.h"
  20
  21 template <class CharT>
  22 void test() {
  23   // operator* should return correct value
  24   {
  25     auto iss = make_string_stream<CharT>("1 2 345 ");
  26     std::ranges::basic_istream_view<int, CharT> isv{iss};
  27     auto it                              = isv.begin();
  28     std::same_as<int&> decltype(auto) v1 = *it;
  29     assert(v1 == 1);
  30   }
  31
  32   // operator* should return the same reference to the value stored in the view
  33   {
  34     auto iss = make_string_stream<CharT>("1 2 345 ");
  35     std::ranges::basic_istream_view<int, CharT> isv{iss};
  36     using Iter = std::ranges::iterator_t<decltype(isv)>;
  37
  38     Iter it1{isv};
  39     Iter it2{isv};
  40     assert(&*it1 == &*it2);
  41   }
  42 }
  43
  44 int main(int, char**) {
  45   test<char>();
  46 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  47   test<wchar_t>();
  48 #endif
  49
  50   return 0;
  51 }