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// UNSUPPORTED: c++03, c++11, c++14, c++17
9
10// <forward_list>
11
12// template <class T, class Allocator, class U>
13// typename forward_list<T, Allocator>::size_type
14// erase(forward_list<T, Allocator>& c, const U& value); // constexpr since C++26
15
16#include <forward_list>
17#include <optional>
18
19#include "test_macros.h"
20#include "test_allocator.h"
21#include "min_allocator.h"
22
23template <class S, class U>
24TEST_CONSTEXPR_CXX26 void test0(S s, U val, S expected, std::size_t expected_erased_count) {
25 ASSERT_SAME_TYPE(typename S::size_type, decltype(std::erase(s, val)));
26 assert(expected_erased_count == std::erase(s, val));
27 assert(s == expected);
28}
29
30template <class S>
31TEST_CONSTEXPR_CXX26 void test() {
32 test0(S(), 1, S(), 0);
33
34 test0(S({1}), 1, S(), 1);
35 test0(S({1}), 2, S({1}), 0);
36
37 test0(S({1, 2}), 1, S({2}), 1);
38 test0(S({1, 2}), 2, S({1}), 1);
39 test0(S({1, 2}), 3, S({1, 2}), 0);
40 test0(S({1, 1}), 1, S(), 2);
41 test0(S({1, 1}), 3, S({1, 1}), 0);
42
43 test0(S({1, 2, 3}), 1, S({2, 3}), 1);
44 test0(S({1, 2, 3}), 2, S({1, 3}), 1);
45 test0(S({1, 2, 3}), 3, S({1, 2}), 1);
46 test0(S({1, 2, 3}), 4, S({1, 2, 3}), 0);
47
48 test0(S({1, 1, 1}), 1, S(), 3);
49 test0(S({1, 1, 1}), 2, S({1, 1, 1}), 0);
50 test0(S({1, 1, 2}), 1, S({2}), 2);
51 test0(S({1, 1, 2}), 2, S({1, 1}), 1);
52 test0(S({1, 1, 2}), 3, S({1, 1, 2}), 0);
53 test0(S({1, 2, 2}), 1, S({2, 2}), 1);
54 test0(S({1, 2, 2}), 2, S({1}), 2);
55 test0(S({1, 2, 2}), 3, S({1, 2, 2}), 0);
56
57 // Test cross-type erasure
58 using opt = std::optional<typename S::value_type>;
59 test0(S({1, 2, 1}), opt(), S({1, 2, 1}), 0);
60 test0(S({1, 2, 1}), opt(1), S({2}), 2);
61 test0(S({1, 2, 1}), opt(2), S({1, 1}), 1);
62 test0(S({1, 2, 1}), opt(3), S({1, 2, 1}), 0);
63}
64
65TEST_CONSTEXPR_CXX26 bool test() {
66 test<std::forward_list<int>>();
67 test<std::forward_list<int, min_allocator<int>>>();
68 test<std::forward_list<int, test_allocator<int>>>();
69 test<std::forward_list<long>>();
70 test<std::forward_list<double>>();
71
72 return true;
73}
74
75int main(int, char**) {
76 assert(test());
77#if TEST_STD_VER >= 26
78 static_assert(test());
79#endif
80
81 return 0;
82}
83

source code of libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase.pass.cpp