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 // <queue> 10 // UNSUPPORTED: c++03, c++11, c++14 11 // UNSUPPORTED: clang-5, apple-clang-9 12 // UNSUPPORTED: libcpp-no-deduction-guides 13 // Clang 5 will generate bad implicit deduction guides 14 // Specifically, for the copy constructor. 15 16 // template<class Container> 17 // queue(Container) -> queue<typename Container::value_type, Container>; 18 // 19 // template<class Container, class Allocator> 20 // queue(Container, Allocator) -> queue<typename Container::value_type, Container>; 21 22 23 #include <queue> 24 #include <list> 25 #include <iterator> 26 #include <cassert> 27 #include <cstddef> 28 #include <climits> // INT_MAX 29 30 #include "test_macros.h" 31 #include "test_iterators.h" 32 #include "test_allocator.h" 33 34 struct A {}; 35 36 int main(int, char**) 37 { 38 39 // Test the explicit deduction guides 40 { 41 std::list<int> l{0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; 42 std::queue que(l); 43 44 static_assert(std::is_same_v<decltype(que), std::queue<int, std::list<int>>>, ""); 45 assert(que.size() == l.size()); 46 assert(que.back() == l.back()); 47 } 48 49 { 50 std::list<long, test_allocator<long>> l{10, 11, 12, 13, 14, 15, 16, 17, 18, 19 }; 51 std::queue que(l, test_allocator<long>(0,2)); // different allocator 52 static_assert(std::is_same_v<decltype(que)::container_type, std::list<long, test_allocator<long>>>, ""); 53 static_assert(std::is_same_v<decltype(que)::value_type, long>, ""); 54 assert(que.size() == 10); 55 assert(que.back() == 19); 56 // I'd like to assert that we've gotten the right allocator in the queue, but 57 // I don't know how to get at the underlying container. 58 } 59 60 // Test the implicit deduction guides 61 { 62 // We don't expect this one to work - no way to implicitly get value_type 63 // std::queue que(std::allocator<int>()); // queue (allocator &) 64 } 65 66 { 67 std::queue<A> source; 68 std::queue que(source); // queue(queue &) 69 static_assert(std::is_same_v<decltype(que)::value_type, A>, ""); 70 static_assert(std::is_same_v<decltype(que)::container_type, std::deque<A>>, ""); 71 assert(que.size() == 0); 72 } 73 74 { 75 // This one is odd - you can pass an allocator in to use, but the allocator 76 // has to match the type of the one used by the underlying container 77 typedef short T; 78 typedef test_allocator<T> A; 79 typedef std::deque<T, A> C; 80 81 C c{0,1,2,3}; 82 std::queue<T, C> source(c); 83 std::queue que(source, A(2)); // queue(queue &, allocator) 84 static_assert(std::is_same_v<decltype(que)::value_type, T>, ""); 85 static_assert(std::is_same_v<decltype(que)::container_type, C>, ""); 86 assert(que.size() == 4); 87 assert(que.back() == 3); 88 } 89 90 91 return 0; 92 } 93