libcxx/test/std/algorithms/algorithms.results/in_in_out_result.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 // template <class I1, class I2, class O>
  12 // struct in_in_out_result;
  13
  14 #include <algorithm>
  15 #include <cassert>
  16 #include <type_traits>
  17
  18 #include "MoveOnly.h"
  19
  20 struct A {
  21   explicit A(int);
  22 };
  23 // no implicit conversion
  24 static_assert(!std::is_constructible_v<std::ranges::in_in_out_result<A, A, A>,
  25                                        std::ranges::in_in_out_result<int, int, int>>);
  26
  27 struct B {
  28   B(int);
  29 };
  30 // implicit conversion
  31 static_assert(std::is_constructible_v<std::ranges::in_in_out_result<B, B, B>, std::ranges::in_in_out_result<int, int, int>>);
  32 static_assert(std::is_constructible_v<std::ranges::in_in_out_result<B, B, B>, std::ranges::in_in_out_result<int, int, int>&>);
  33 static_assert(std::is_constructible_v<std::ranges::in_in_out_result<B, B, B>, const std::ranges::in_in_out_result<int, int, int>>);
  34 static_assert(std::is_constructible_v<std::ranges::in_in_out_result<B, B, B>, const std::ranges::in_in_out_result<int, int, int>&>);
  35
  36 struct C {
  37   C(int&);
  38 };
  39 static_assert(!std::is_constructible_v<std::ranges::in_in_out_result<C, C, C>, std::ranges::in_in_out_result<int, int, int>&>);
  40
  41 // has to be convertible via const&
  42 static_assert(std::is_convertible_v<std::ranges::in_in_out_result<int, int, int>&, std::ranges::in_in_out_result<long, long, long>>);
  43 static_assert(std::is_convertible_v<const std::ranges::in_in_out_result<int, int, int>&, std::ranges::in_in_out_result<long, long, long>>);
  44 static_assert(std::is_convertible_v<std::ranges::in_in_out_result<int, int, int>&&, std::ranges::in_in_out_result<long, long, long>>);
  45 static_assert(std::is_convertible_v<const std::ranges::in_in_out_result<int, int, int>&&, std::ranges::in_in_out_result<long, long, long>>);
  46
  47 // should be move constructible
  48 static_assert(std::is_move_constructible_v<std::ranges::in_in_out_result<MoveOnly, int, int>>);
  49 static_assert(std::is_move_constructible_v<std::ranges::in_in_out_result<int, MoveOnly, int>>);
  50 static_assert(std::is_move_constructible_v<std::ranges::in_in_out_result<int, int, MoveOnly>>);
  51
  52 // should not be copy constructible
  53 static_assert(!std::is_copy_constructible_v<std::ranges::in_in_out_result<MoveOnly, int, int>>);
  54 static_assert(!std::is_copy_constructible_v<std::ranges::in_in_out_result<int, MoveOnly, int>>);
  55 static_assert(!std::is_copy_constructible_v<std::ranges::in_in_out_result<int, int, MoveOnly>>);
  56
  57 struct NotConvertible {};
  58 // conversions should not work if there is no conversion
  59 static_assert(!std::is_convertible_v<std::ranges::in_in_out_result<NotConvertible, int, int>, std::ranges::in_in_out_result<int, int, int>>);
  60 static_assert(!std::is_convertible_v<std::ranges::in_in_out_result<int, NotConvertible, int>, std::ranges::in_in_out_result<int, int, int>>);
  61 static_assert(!std::is_convertible_v<std::ranges::in_in_out_result<int, int, NotConvertible>, std::ranges::in_in_out_result<int, int, int>>);
  62
  63 template <class T>
  64 struct ConvertibleFrom {
  65   constexpr ConvertibleFrom(T c) : content{c} {}
  66   T content;
  67 };
  68
  69 constexpr bool test() {
  70   // Checks that conversion operations are correct.
  71   {
  72     std::ranges::in_in_out_result<int, double, float> res{10, 0., 1.f};
  73     assert(res.in1 == 10);
  74     assert(res.in2 == 0.);
  75     assert(res.out == 1.f);
  76     std::ranges::in_in_out_result<ConvertibleFrom<int>, ConvertibleFrom<double>, ConvertibleFrom<float>> res2 = res;
  77     assert(res2.in1.content == 10);
  78     assert(res2.in2.content == 0.);
  79     assert(res2.out.content == 1.f);
  80   }
  81
  82   // Checks that conversions are possible when one of the types is move-only.
  83   {
  84     std::ranges::in_in_out_result<MoveOnly, int, int> res1{MoveOnly{}, 0, 0};
  85     assert(res1.in1.get() == 1);
  86     auto res2 = static_cast<std::ranges::in_in_out_result<MoveOnly, int, int>>(std::move(res1));
  87     assert(res1.in1.get() == 0);
  88     assert(res2.in1.get() == 1);
  89   }
  90
  91   // Checks that structured bindings get the correct values.
  92   {
  93     auto [in1, in2, out] = std::ranges::in_in_out_result<int, int, int>{1, 2, 3};
  94     assert(in1 == 1);
  95     assert(in2 == 2);
  96     assert(out == 3);
  97   }
  98   return true;
  99 }
 100
 101 int main(int, char**) {
 102   test();
 103   static_assert(test());
 104
 105   return 0;
 106 }