libstdc++-v3/testsuite/22_locale/conversions/buffer/3.cc

   1 // Copyright (C) 2017-2019 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do run { target c++11 } }
  19
  20 #include <locale>
  21 #include <streambuf>
  22 #include <testsuite_hooks.h>
  23
  24 struct streambuf : std::streambuf
  25 {
  26   int_type underflow() override
  27   {
  28     if (c != '\0')
  29     {
  30       this->setg(&c, &c, &c + 1);
  31       return *this->gptr();
  32     }
  33     c = '\0';
  34     return traits_type::eof();
  35   }
  36
  37 private:
  38   char c = 'a';
  39 };
  40
  41 struct codecvt : std::codecvt<wchar_t, char, std::mbstate_t> { };
  42
  43 void
  44 test01()
  45 {
  46   // https://gcc.gnu.org/ml/libstdc++/2017-11/msg00022.html
  47   streambuf sb;
  48   std::wbuffer_convert<codecvt> conv(&sb);
  49   VERIFY( sb.in_avail() == 0 );
  50   wchar_t c = conv.sgetc();
  51   VERIFY( c == L'a' );
  52 }
  53
  54 int
  55 main()
  56 {
  57   test01();
  58 }