libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.members/str.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <sstream>
  10
  11 // template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
  12 // class basic_stringbuf
  13
  14 // void str(const basic_string<charT,traits,Allocator>& s);
  15
  16 #include <sstream>
  17 #include <string>
  18 #include <cassert>
  19
  20 #include "test_macros.h"
  21
  22 struct StringBuf : std::stringbuf {
  23   explicit StringBuf(const char* s, std::ios_base::openmode mode) : basic_stringbuf(s, mode) {}
  24   void public_setg(int a, int b, int c) {
  25     char* p = eback();
  26     this->setg(p + a, p + b, p + c);
  27   }
  28 };
  29
  30 static void test_altered_sequence_pointers() {
  31   {
  32     StringBuf src("hello world", std::ios_base::in);
  33     src.public_setg(4, 6, 9);
  34     std::stringbuf dest;
  35     dest            = std::move(src);
  36     std::string str = dest.str();
  37     assert(5 <= str.size() && str.size() <= 11);
  38     LIBCPP_ASSERT(str == "o wor");
  39     LIBCPP_ASSERT(dest.str() == "o wor");
  40   }
  41   {
  42     StringBuf src("hello world", std::ios_base::in);
  43     src.public_setg(4, 6, 9);
  44     std::stringbuf dest;
  45     dest.swap(src);
  46     std::string str = dest.str();
  47     assert(5 <= str.size() && str.size() <= 11);
  48     LIBCPP_ASSERT(str == "o wor");
  49     LIBCPP_ASSERT(dest.str() == "o wor");
  50   }
  51 }
  52
  53 int main(int, char**)
  54 {
  55   test_altered_sequence_pointers();
  56   {
  57     std::stringbuf buf("testing");
  58     assert(buf.str() == "testing");
  59     buf.str("another test");
  60     assert(buf.str() == "another test");
  61   }
  62 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  63     {
  64         std::wstringbuf buf(L"testing");
  65         assert(buf.str() == L"testing");
  66         buf.str(L"another test");
  67         assert(buf.str() == L"another test");
  68     }
  69 #endif
  70
  71   return 0;
  72 }