92 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// <sstream>12 13// template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >14// class basic_stringbuf15 16// basic_string<charT, traits, Allocator> str() &&;17 18#include <sstream>19#include <cassert>20 21#include "make_string.h"22#include "test_macros.h"23 24#define STR(S) MAKE_STRING(CharT, S)25 26template <class CharT>27static void test() {28 {29 std::basic_stringbuf<CharT> buf(STR("testing"));30 std::basic_string<CharT> s = std::move(buf).str();31 assert(s == STR("testing"));32 assert(buf.view().empty());33 }34 {35 std::basic_stringbuf<CharT> buf;36 std::basic_string<CharT> s = std::move(buf).str();37 assert(s.empty());38 assert(buf.view().empty());39 }40 {41 std::basic_stringbuf<CharT> buf(STR("a very long string that exceeds the small string optimization buffer length"));42 const CharT* p = buf.view().data();43 std::basic_string<CharT> s = std::move(buf).str();44 assert(s.data() == p); // the allocation was pilfered45 assert(buf.view().empty());46 }47}48 49struct StringBuf : std::stringbuf {50 using basic_stringbuf::basic_stringbuf;51 void public_setg(int a, int b, int c) {52 char* p = eback();53 this->setg(p + a, p + b, p + c);54 }55};56 57static void test_altered_sequence_pointers() {58 {59 auto src = StringBuf("hello world", std::ios_base::in);60 src.public_setg(4, 6, 9);61 std::stringbuf dest;62 dest = std::move(src);63 std::string view = std::string(dest.view());64 std::string str = std::move(dest).str();65 assert(view == str);66 LIBCPP_ASSERT(str == "o wor");67 assert(dest.str().empty());68 assert(dest.view().empty());69 }70 {71 auto src = StringBuf("hello world", std::ios_base::in);72 src.public_setg(4, 6, 9);73 std::stringbuf dest;74 dest.swap(src);75 std::string view = std::string(dest.view());76 std::string str = std::move(dest).str();77 assert(view == str);78 LIBCPP_ASSERT(str == "o wor");79 assert(dest.str().empty());80 assert(dest.view().empty());81 }82}83 84int main(int, char**) {85 test<char>();86#ifndef TEST_HAS_NO_WIDE_CHARACTERS87 test<wchar_t>();88#endif89 test_altered_sequence_pointers();90 return 0;91}92