libcxx/test/std/iterators/predef.iterators/iterators.common/arrow.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: c++03, c++11, c++14, c++17
  10
  11 // auto operator->() const
  12 //   requires see below;
  13
  14 #include <iterator>
  15 #include <cassert>
  16 #include <concepts>
  17
  18 #include "test_iterators.h"
  19 #include "test_macros.h"
  20 #include "types.h"
  21
  22 void test() {
  23   // Case 1: http://eel.is/c++draft/iterators.common#common.iter.access-5.1
  24   {
  25     auto check = []<class Iterator>() {
  26       int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
  27       Iterator iter(buffer);
  28       using Common = std::common_iterator<Iterator, sentinel_wrapper<Iterator>>;
  29
  30       Common common(iter);
  31       std::same_as<Iterator> decltype(auto) result = common.operator->();
  32       assert(base(result) == buffer);
  33
  34       Common const ccommon(iter);
  35       std::same_as<Iterator> decltype(auto) cresult = ccommon.operator->();
  36       assert(base(cresult) == buffer);
  37     };
  38
  39     check.operator()<contiguous_iterator<int*>>();
  40     check.operator()<int*>();
  41   }
  42
  43   // Case 2: http://eel.is/c++draft/iterators.common#common.iter.access-5.2
  44   {
  45     auto check = []<class Iterator>() {
  46       int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
  47       Iterator iter(buffer);
  48       using Common = std::common_iterator<Iterator, sentinel_type<int*>>;
  49
  50       Common common(iter);
  51       std::same_as<int*> decltype(auto) result = common.operator->();
  52       assert(result == buffer);
  53
  54       Common const ccommon(iter);
  55       std::same_as<int*> decltype(auto) cresult = ccommon.operator->();
  56       assert(cresult == buffer);
  57     };
  58
  59     check.operator()<simple_iterator<int*>>();
  60     check.operator()<cpp17_input_iterator<int*>>();
  61     // cpp20_input_iterator can't be used with common_iterator because it's not copyable
  62     check.operator()<forward_iterator<int*>>();
  63     check.operator()<bidirectional_iterator<int*>>();
  64     check.operator()<random_access_iterator<int*>>();
  65   }
  66
  67   // Case 3: http://eel.is/c++draft/iterators.common#common.iter.access-5.3
  68   {
  69     auto check = []<class Iterator>() {
  70       int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
  71       Iterator iter(buffer);
  72       using Common = std::common_iterator<Iterator, sentinel_type<int*>>;
  73
  74       Common common(iter);
  75       auto proxy                                     = common.operator->();
  76       std::same_as<int const*> decltype(auto) result = proxy.operator->();
  77       assert(result != buffer); // we copied to a temporary proxy
  78       assert(*result == *buffer);
  79
  80       Common const ccommon(iter);
  81       auto cproxy                                     = ccommon.operator->();
  82       std::same_as<int const*> decltype(auto) cresult = cproxy.operator->();
  83       assert(cresult != buffer); // we copied to a temporary proxy
  84       assert(*cresult == *buffer);
  85     };
  86
  87     check.operator()<value_iterator<int*>>();
  88     check.operator()<void_plus_plus_iterator<int*>>();
  89   }
  90 }
  91
  92 int main(int, char**) {
  93   test();
  94
  95   return 0;
  96 }