xref: /llvm-project/libcxx/test/std/algorithms/ranges_robust_against_differing_projections.pass.cpp (revision b8cb1dc9ea87faa8e8e9ab7a31710a8c0bb8b084)
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 support the case where the ranges they operate on have different value types and the given
14 // projection functors are different (each projection applies to a different value type).
15 
16 #include <algorithm>
17 
18 #include <array>
19 #include <functional>
20 #include <iterator>
21 #include <ranges>
22 #include <utility>
23 
24 // (in1, in2, ...)
25 template <class Func, std::ranges::range Input1, std::ranges::range Input2, class ...Args>
26 constexpr void test(Func&& func, Input1& in1, Input2& in2, Args&& ...args) {
27   func(in1.begin(), in1.end(), in2.begin(), in2.end(), std::forward<Args>(args)...);
28   func(in1, in2, std::forward<Args>(args)...);
29 }
30 
31 constexpr bool test_all() {
32   struct A {
33     int x = 0;
34 
35     constexpr A() = default;
36     constexpr A(int value) : x(value) {}
37     constexpr operator int() const { return x; }
38 
39     constexpr auto operator<=>(const A&) const = default;
40   };
41 
42   std::array in = {1, 2, 3};
43   std::array in2 = {A{4}, A{5}, A{6}};
44 
45   std::array output = {7, 8, 9, 10, 11, 12};
46   auto out = output.begin();
47   std::array output2 = {A{7}, A{8}, A{9}, A{10}, A{11}, A{12}};
48   auto out2 = output2.begin();
49 
50   std::ranges::equal_to eq;
51   std::ranges::less less;
52   auto sum = [](int lhs, A rhs) { return lhs + rhs.x; };
53   auto proj1 = [](int x) { return x * -1; };
54   auto proj2 = [](A a) { return a.x * -1; };
55 
56   test(std::ranges::equal, in, in2, eq, proj1, proj2);
57   test(std::ranges::lexicographical_compare, in, in2, eq, proj1, proj2);
58   test(std::ranges::is_permutation, in, in2, eq, proj1, proj2);
59   test(std::ranges::includes, in, in2, less, proj1, proj2);
60   test(std::ranges::find_first_of, in, in2, eq, proj1, proj2);
61   test(std::ranges::mismatch, in, in2, eq, proj1, proj2);
62   test(std::ranges::search, in, in2, eq, proj1, proj2);
63   test(std::ranges::find_end, in, in2, eq, proj1, proj2);
64   test(std::ranges::transform, in, in2, out, sum, proj1, proj2);
65   test(std::ranges::transform, in, in2, out2, sum, proj1, proj2);
66   test(std::ranges::partial_sort_copy, in, in2, less, proj1, proj2);
67   test(std::ranges::merge, in, in2, out, less, proj1, proj2);
68   test(std::ranges::merge, in, in2, out2, less, proj1, proj2);
69   test(std::ranges::set_intersection, in, in2, out, less, proj1, proj2);
70   test(std::ranges::set_intersection, in, in2, out2, less, proj1, proj2);
71   test(std::ranges::set_difference, in, in2, out, less, proj1, proj2);
72   test(std::ranges::set_difference, in, in2, out2, less, proj1, proj2);
73   test(std::ranges::set_symmetric_difference, in, in2, out, less, proj1, proj2);
74   test(std::ranges::set_symmetric_difference, in, in2, out2, less, proj1, proj2);
75   test(std::ranges::set_union, in, in2, out, less, proj1, proj2);
76   test(std::ranges::set_union, in, in2, out2, less, proj1, proj2);
77   //test(std::ranges::starts_with, in, in2, eq, proj1, proj2);
78   //test(std::ranges::ends_with, in, in2, eq, proj1, proj2);
79 
80   return true;
81 }
82 
83 int main(int, char**) {
84   test_all();
85   static_assert(test_all());
86 
87   return 0;
88 }
89