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++98, c++03, c++11, c++14, c++17
9 
10 // <string>
11 
12 // template <class charT, class traits, class Allocator, class U>
13 //   typename basic_string<charT, traits, Allocator>::size_type
14 //   erase(basic_string<charT, traits, Allocator>& c, const U& value);
15 
16 #include <string>
17 #include <optional>
18 
19 #include "test_macros.h"
20 #include "test_allocator.h"
21 #include "min_allocator.h"
22 
23 template <class S, class U>
24 void test0(S s, U val, S expected, 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   LIBCPP_ASSERT(s.__invariants());
28   assert(s == expected);
29 }
30 
31 template <class S>
32 void test()
33 {
34 
35   test0(S(""), 'a', S(""), 0);
36 
37   test0(S("a"), 'a', S(""), 1);
38   test0(S("a"), 'b', S("a"), 0);
39 
40   test0(S("ab"), 'a', S("b"), 1);
41   test0(S("ab"), 'b', S("a"), 1);
42   test0(S("ab"), 'c', S("ab"), 0);
43   test0(S("aa"), 'a', S(""), 2);
44   test0(S("aa"), 'c', S("aa"), 0);
45 
46   test0(S("abc"), 'a', S("bc"), 1);
47   test0(S("abc"), 'b', S("ac"), 1);
48   test0(S("abc"), 'c', S("ab"), 1);
49   test0(S("abc"), 'd', S("abc"), 0);
50 
51   test0(S("aab"), 'a', S("b"), 2);
52   test0(S("aab"), 'b', S("aa"), 1);
53   test0(S("aab"), 'c', S("aab"), 0);
54   test0(S("abb"), 'a', S("bb"), 1);
55   test0(S("abb"), 'b', S("a"), 2);
56   test0(S("abb"), 'c', S("abb"), 0);
57   test0(S("aaa"), 'a', S(""), 3);
58   test0(S("aaa"), 'b', S("aaa"), 0);
59 
60   //  Test cross-type erasure
61   using opt = std::optional<typename S::value_type>;
62   test0(S("aba"), opt(), S("aba"), 0);
63   test0(S("aba"), opt('a'), S("b"), 2);
64   test0(S("aba"), opt('b'), S("aa"), 1);
65   test0(S("aba"), opt('c'), S("aba"), 0);
66 }
67 
68 int main(int, char**)
69 {
70     test<std::string>();
71     test<std::basic_string<char, std::char_traits<char>, min_allocator<char>>> ();
72     test<std::basic_string<char, std::char_traits<char>, test_allocator<char>>> ();
73 
74   return 0;
75 }
76