libcxx/test/std/algorithms/ranges_robust_against_omitting_invoke.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 // <algorithm>
  12 //
  13 // Range algorithms should use `std::invoke` to call the given projection(s) (and predicates, where applicable).
  14
  15 #include <algorithm>
  16
  17 #include <array>
  18 #include <concepts>
  19 #include <initializer_list>
  20 #include <iterator>
  21 #include <ranges>
  22
  23 struct Foo {
  24   int val;
  25   constexpr bool unary_pred() const { return val > 0; }
  26   constexpr bool binary_pred(const Foo& rhs) const { return val < rhs.val; }
  27   constexpr auto operator<=>(const Foo&) const = default;
  28 };
  29
  30 struct Bar {
  31   Foo val;
  32   Bar create() const { return Bar(); }
  33 };
  34
  35 // Invokes both the (iterator, sentinel, ...) and the (range, ...) overloads of the given niebloid.
  36
  37 // (in, ...)
  38 template <class Func, std::ranges::range Input, class... Args>
  39 constexpr void test(Func&& func, Input& in, Args&&... args) {
  40   (void)func(in.begin(), in.end(), std::forward<Args>(args)...);
  41   (void)func(in, std::forward<Args>(args)...);
  42 }
  43
  44 // (in1, in2, ...)
  45 template <class Func, std::ranges::range Input, class... Args>
  46 constexpr void test(Func&& func, Input& in1, Input& in2, Args&&... args) {
  47   (void)func(in1.begin(), in1.end(), in2.begin(), in2.end(), std::forward<Args>(args)...);
  48   (void)func(in1, in2, std::forward<Args>(args)...);
  49 }
  50
  51 // (in, mid, ...)
  52 template <class Func, std::ranges::range Input, class... Args>
  53 constexpr void test_mid(Func&& func, Input& in, std::ranges::iterator_t<Input> mid, Args&&... args) {
  54   (void)func(in.begin(), mid, in.end(), std::forward<Args>(args)...);
  55   (void)func(in, mid, std::forward<Args>(args)...);
  56 }
  57
  58 constexpr bool test_all() {
  59   std::array in  = {Bar{Foo{1}}, Bar{Foo{2}}, Bar{Foo{3}}};
  60   std::array in2 = {Bar{Foo{4}}, Bar{Foo{5}}, Bar{Foo{6}}};
  61   auto mid       = in.begin() + 1;
  62
  63   std::array output = {Bar{Foo{7}}, Bar{Foo{8}}, Bar{Foo{9}}, Bar{Foo{10}}, Bar{Foo{11}}, Bar{Foo{12}}};
  64   auto out          = output.begin();
  65   auto out2         = output.begin() + 1;
  66
  67   Bar a{Foo{1}};
  68   Bar b{Foo{2}};
  69   Bar c{Foo{3}};
  70
  71   Foo x{2};
  72   std::size_t count = 1;
  73
  74   test(std::ranges::any_of, in, &Foo::unary_pred, &Bar::val);
  75   test(std::ranges::all_of, in, &Foo::unary_pred, &Bar::val);
  76   test(std::ranges::none_of, in, &Foo::unary_pred, &Bar::val);
  77   test(std::ranges::find, in, x, &Bar::val);
  78   test(std::ranges::find_if, in, &Foo::unary_pred, &Bar::val);
  79   test(std::ranges::find_if_not, in, &Foo::unary_pred, &Bar::val);
  80   test(std::ranges::find_first_of, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
  81   test(std::ranges::adjacent_find, in, &Foo::binary_pred, &Bar::val);
  82   test(std::ranges::mismatch, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
  83   test(std::ranges::equal, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
  84   test(std::ranges::lexicographical_compare, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
  85   test(std::ranges::partition_point, in, &Foo::unary_pred, &Bar::val);
  86   test(std::ranges::lower_bound, in, x, &Foo::binary_pred, &Bar::val);
  87   test(std::ranges::upper_bound, in, x, &Foo::binary_pred, &Bar::val);
  88   test(std::ranges::equal_range, in, x, &Foo::binary_pred, &Bar::val);
  89   test(std::ranges::binary_search, in, x, &Foo::binary_pred, &Bar::val);
  90
  91   // min
  92   (void)std::ranges::min(a, b, &Foo::binary_pred, &Bar::val);
  93   (void)std::ranges::min(std::initializer_list<Bar>{a, b}, &Foo::binary_pred, &Bar::val);
  94   (void)std::ranges::min(in, &Foo::binary_pred, &Bar::val);
  95   // max
  96   (void)std::ranges::max(a, b, &Foo::binary_pred, &Bar::val);
  97   (void)std::ranges::max(std::initializer_list<Bar>{a, b}, &Foo::binary_pred, &Bar::val);
  98   (void)std::ranges::max(in, &Foo::binary_pred, &Bar::val);
  99   // minmax
 100   (void)std::ranges::minmax(a, b, &Foo::binary_pred, &Bar::val);
 101   (void)std::ranges::minmax(std::initializer_list<Bar>{a, b}, &Foo::binary_pred, &Bar::val);
 102   (void)std::ranges::minmax(in, &Foo::binary_pred, &Bar::val);
 103
 104   test(std::ranges::min_element, in, &Foo::binary_pred, &Bar::val);
 105   test(std::ranges::max_element, in, &Foo::binary_pred, &Bar::val);
 106   test(std::ranges::minmax_element, in, &Foo::binary_pred, &Bar::val);
 107   test(std::ranges::count, in, x, &Bar::val);
 108   test(std::ranges::count_if, in, &Foo::unary_pred, &Bar::val);
 109   test(std::ranges::search, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
 110   test(std::ranges::search_n, in, count, x, &Foo::binary_pred, &Bar::val);
 111   test(std::ranges::find_end, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
 112   test(std::ranges::is_partitioned, in, &Foo::unary_pred, &Bar::val);
 113   test(std::ranges::is_sorted, in, &Foo::binary_pred, &Bar::val);
 114   test(std::ranges::is_sorted_until, in, &Foo::binary_pred, &Bar::val);
 115   test(std::ranges::includes, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
 116   test(std::ranges::is_heap, in, &Foo::binary_pred, &Bar::val);
 117   test(std::ranges::is_heap_until, in, &Foo::binary_pred, &Bar::val);
 118   (void)std::ranges::clamp(b, a, c, &Foo::binary_pred, &Bar::val);
 119   test(std::ranges::is_permutation, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
 120   test(std::ranges::for_each, in, &Foo::unary_pred, &Bar::val);
 121   std::ranges::for_each_n(in.begin(), count, &Foo::unary_pred, &Bar::val);
 122   // `copy`, `copy_n` and `copy_backward` have neither a projection nor a predicate.
 123   test(std::ranges::copy_if, in, out, &Foo::unary_pred, &Bar::val);
 124   // `move` and `move_backward` have neither a projection nor a predicate.
 125   // `fill` and `fill_n` have neither a projection nor a predicate.
 126   {
 127     std::array out_transform = {false, true, true};
 128     test(std::ranges::transform, in, out_transform.begin(), &Foo::unary_pred, &Bar::val);
 129   }
 130   // Whether `ranges::generate{,_n}` invokes `gen` via `std::invoke` is not observable.
 131   test(std::ranges::remove_copy, in, out, x, &Bar::val);
 132   test(std::ranges::remove_copy_if, in, out, &Foo::unary_pred, &Bar::val);
 133   // `replace*` algorithms only use the projection to compare the elements, not to write them.
 134   test(std::ranges::replace, in, x, a, &Bar::val);
 135   test(std::ranges::replace_if, in, &Foo::unary_pred, a, &Bar::val);
 136   test(std::ranges::replace_copy, in, out, x, a, &Bar::val);
 137   test(std::ranges::replace_copy_if, in, out, &Foo::unary_pred, a, &Bar::val);
 138   // `swap_ranges` has neither a projection nor a predicate.
 139   // `reverse_copy` has neither a projection nor a predicate.
 140   // `rotate_copy` has neither a projection nor a predicate.
 141   // For `sample`, whether the given generator is invoked via `std::invoke` is not observable.
 142   test(std::ranges::unique_copy, in, out, &Foo::binary_pred, &Bar::val);
 143   test(std::ranges::partition_copy, in, out, out2, &Foo::unary_pred, &Bar::val);
 144   test(std::ranges::partial_sort_copy, in, in2, &Foo::binary_pred, &Bar::val, &Bar::val);
 145   test(std::ranges::merge, in, in2, out, &Foo::binary_pred, &Bar::val, &Bar::val);
 146   test(std::ranges::set_difference, in, in2, out, &Foo::binary_pred, &Bar::val, &Bar::val);
 147   test(std::ranges::set_intersection, in, in2, out, &Foo::binary_pred, &Bar::val, &Bar::val);
 148   test(std::ranges::set_symmetric_difference, in, in2, out, &Foo::binary_pred, &Bar::val, &Bar::val);
 149   test(std::ranges::set_union, in, in2, out, &Foo::binary_pred, &Bar::val, &Bar::val);
 150   test(std::ranges::remove, in, x, &Bar::val);
 151   test(std::ranges::remove_if, in, &Foo::unary_pred, &Bar::val);
 152   // `reverse` has neither a projection nor a predicate.
 153   // `rotate` has neither a projection nor a predicate.
 154   // For `shuffle`, whether the given generator is invoked via `std::invoke` is not observable.
 155   test(std::ranges::unique, in, &Foo::binary_pred, &Bar::val);
 156   test(std::ranges::partition, in, &Foo::unary_pred, &Bar::val);
 157   if (!std::is_constant_evaluated())
 158     test(std::ranges::stable_partition, in, &Foo::unary_pred, &Bar::val);
 159   test(std::ranges::sort, in, &Foo::binary_pred, &Bar::val);
 160   if (!std::is_constant_evaluated())
 161     test(std::ranges::stable_sort, in, &Foo::binary_pred, &Bar::val);
 162   test_mid(std::ranges::partial_sort, in, mid, &Foo::binary_pred, &Bar::val);
 163   test_mid(std::ranges::nth_element, in, mid, &Foo::binary_pred, &Bar::val);
 164   if (!std::is_constant_evaluated())
 165     test_mid(std::ranges::inplace_merge, in, mid, &Foo::binary_pred, &Bar::val);
 166   test(std::ranges::make_heap, in, &Foo::binary_pred, &Bar::val);
 167   test(std::ranges::push_heap, in, &Foo::binary_pred, &Bar::val);
 168   test(std::ranges::pop_heap, in, &Foo::binary_pred, &Bar::val);
 169   test(std::ranges::sort_heap, in, &Foo::binary_pred, &Bar::val);
 170   test(std::ranges::prev_permutation, in, &Foo::binary_pred, &Bar::val);
 171   test(std::ranges::next_permutation, in, &Foo::binary_pred, &Bar::val);
 172
 173   return true;
 174 }
 175
 176 int main(int, char**) {
 177   test_all();
 178   static_assert(test_all());
 179
 180   return 0;
 181 }