81 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// <string>12 13// template <class charT, class traits, class Allocator, class U>14// constexpr typename basic_string<charT, traits, Allocator>::size_type15// 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 erasure60 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