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, c++20
10// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-steps): -fconstexpr-steps=2000000
11
12// template<container-compatible-range<T> R>
13// constexpr void assign_range(R&& rg); // C++23
14
15#include <vector>
16
17#include "../../insert_range_sequence_containers.h"
18#include "asan_testing.h"
19#include "test_macros.h"
20
21// Tested cases:
22// - different kinds of assignments (assigning an {empty/one-element/mid-sized/long range} to an
23// {empty/one-element/full} container);
24// - assigning move-only elements;
25// - an exception is thrown when copying the elements or when allocating new elements.
26constexpr bool test() {
27 static_assert(test_constraints_assign_range<std::vector, int, double>());
28
29 for_all_iterators_and_allocators<int, const int*>(f: []<class Iter, class Sent, class Alloc>() {
30 test_sequence_assign_range<std::vector<int, Alloc>, Iter, Sent>([]([[maybe_unused]] auto&& c) {
31 LIBCPP_ASSERT(c.__invariants());
32 LIBCPP_ASSERT(is_contiguous_container_asan_correct(c));
33 });
34 });
35 test_sequence_assign_range_move_only<std::vector>();
36
37 { // Vector may or may not need to reallocate because of the assignment -- make sure to test both cases.
38 { // Ensure reallocation happens.
39 int in[] = {-1, -2, -3, -4, -5, -6, -7, -8, -9, -10};
40 std::vector<int> v = {1, 2, 3, 4, 5, 6, 7, 8};
41 v.shrink_to_fit();
42 assert(v.capacity() < v.size() + std::ranges::size(in));
43
44 v.assign_range(in);
45 assert(std::ranges::equal(v, in));
46 }
47
48 { // Ensure no reallocation happens -- the input range is shorter than the vector.
49 int in[] = {-1, -2, -3, -4, -5};
50 std::vector<int> v = {1, 2, 3, 4, 5, 6, 7, 8};
51
52 v.assign_range(in);
53 assert(std::ranges::equal(v, in));
54 }
55
56 { // Ensure no reallocation happens -- the input range is longer than the vector but within capacity.
57 int in[] = {-1, -2, -3, -4, -5, -6, -7, -8};
58 std::vector<int> v = {1, 2, 3, 4, 5};
59 v.reserve(std::ranges::size(in));
60 assert(v.capacity() >= std::ranges::size(in));
61
62 v.assign_range(in);
63 assert(std::ranges::equal(v, in));
64 }
65 }
66
67 return true;
68}
69
70int main(int, char**) {
71 test();
72 static_assert(test());
73
74 test_assign_range_exception_safety_throwing_copy<std::vector>();
75 test_assign_range_exception_safety_throwing_allocator<std::vector, int>();
76
77 return 0;
78}
79

source code of libcxx/test/std/containers/sequences/vector/vector.modifiers/assign_range.pass.cpp