libstdc++-v3/testsuite/20_util/optional/relops/96269.cc

   1 // Copyright (C) 2020-2023 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do compile { target c++20 } }
  19
  20 #include <optional>
  21
  22 struct X
  23 {
  24   template <typename T>
  25     bool operator==(const T&) /* not const */ { return false; }
  26
  27   template <typename T>
  28     bool operator!=(const T&) /* not const */ { return false; }
  29
  30   template <typename T>
  31     bool operator<(const T&) /* not const */ { return false; }
  32
  33   template <typename T>
  34     bool operator>(const T&) /* not const */ { return false; }
  35
  36   template <typename T>
  37     bool operator<=(const T&) /* not const */ { return false; }
  38
  39   template <typename T>
  40     bool operator>=(const T&) /* not const */ { return false; }
  41 };
  42
  43 void test01()
  44 {
  45   // PR 96269 optional comparison with nullopt fails
  46   std::optional<X> x;
  47   bool eq [[maybe_unused]] = std::nullopt == x;
  48
  49   bool ne [[maybe_unused]] = std::nullopt != x;
  50   bool lt [[maybe_unused]] = std::nullopt <  x;
  51   bool gt [[maybe_unused]] = std::nullopt >  x;
  52   bool le [[maybe_unused]] = std::nullopt <= x;
  53   bool ge [[maybe_unused]] = std::nullopt >= x;
  54 }
  55
  56 template<typename T>
  57   concept optional_lt_cmp
  58     = requires(std::optional<T> o, T t) { { o < t } -> std::same_as<bool>; };
  59
  60 template<typename T>
  61   concept optional_gt_cmp
  62     = requires(std::optional<T> o, T t) { { o > t } -> std::same_as<bool>; };
  63
  64 template<typename T>
  65   concept optional_le_cmp
  66     = requires(std::optional<T> o, T t) { { o <= t } -> std::same_as<bool>; };
  67
  68 template<typename T>
  69   concept optional_ge_cmp
  70     = requires(std::optional<T> o, T t) { { o >= t } -> std::same_as<bool>; };
  71
  72 static_assert( ! optional_lt_cmp<X> );
  73 static_assert( ! optional_gt_cmp<X> );
  74 static_assert( ! optional_le_cmp<X> );
  75 static_assert( ! optional_ge_cmp<X> );