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// <string>
12
13// template <class charT, class traits, class Allocator, class U>
14// constexpr typename basic_string<charT, traits, Allocator>::size_type
15// erase(basic_string<charT, traits, Allocator>& c, const U& value);
16
17#include <string>
18#include <optional>
19
20#include "test_macros.h"
21#include "test_allocator.h"
22#include "min_allocator.h"
23
24template <class S, class U>
25constexpr void test0(S s, U val, S expected, std::size_t expected_erased_count) {
26 ASSERT_SAME_TYPE(typename S::size_type, decltype(std::erase(s, val)));
27 assert(expected_erased_count == std::erase(s, val));
28 LIBCPP_ASSERT(s.__invariants());
29 assert(s == expected);
30}
31
32template <class S>
33constexpr void test() {
34 test0(S(""), 'a', S(""), 0);
35
36 test0(S("a"), 'a', S(""), 1);
37 test0(S("a"), 'b', S("a"), 0);
38
39 test0(S("ab"), 'a', S("b"), 1);
40 test0(S("ab"), 'b', S("a"), 1);
41 test0(S("ab"), 'c', S("ab"), 0);
42 test0(S("aa"), 'a', S(""), 2);
43 test0(S("aa"), 'c', S("aa"), 0);
44
45 test0(S("abc"), 'a', S("bc"), 1);
46 test0(S("abc"), 'b', S("ac"), 1);
47 test0(S("abc"), 'c', S("ab"), 1);
48 test0(S("abc"), 'd', S("abc"), 0);
49
50 test0(S("aab"), 'a', S("b"), 2);
51 test0(S("aab"), 'b', S("aa"), 1);
52 test0(S("aab"), 'c', S("aab"), 0);
53 test0(S("abb"), 'a', S("bb"), 1);
54 test0(S("abb"), 'b', S("a"), 2);
55 test0(S("abb"), 'c', S("abb"), 0);
56 test0(S("aaa"), 'a', S(""), 3);
57 test0(S("aaa"), 'b', S("aaa"), 0);
58
59 // Test cross-type erasure
60 using opt = std::optional<typename S::value_type>;
61 test0(S("aba"), opt(), S("aba"), 0);
62 test0(S("aba"), opt('a'), S("b"), 2);
63 test0(S("aba"), opt('b'), S("aa"), 1);
64 test0(S("aba"), opt('c'), S("aba"), 0);
65}
66
67constexpr bool test() {
68 test<std::string>();
69 test<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
70 test<std::basic_string<char, std::char_traits<char>, test_allocator<char>>>();
71
72 return true;
73}
74
75int main(int, char**) {
76 test();
77 static_assert(test());
78
79 return 0;
80}
81

source code of libcxx/test/std/strings/strings.erasure/erase.pass.cpp