libstdc++-v3/testsuite/27_io/istringstream_members.cc

   1 // 2000-01-10 bkoz
   2
   3 // Copyright (C) 2000, 2001 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 // USA.
  20
  21 // 27.7.2.2 member functions (istringstream_members)
  22
  23 #include <sstream>
  24 #include <testsuite_hooks.h>
  25
  26 void test01()
  27 {
  28   bool test = true;
  29   std::istringstream is01;
  30   const std::string str00;
  31   const std::string str01 = "123";
  32   std::string str02;
  33   const int i01 = 123;
  34   int a,b;
  35
  36   std::ios_base::iostate state1, state2, statefail, stateeof;
  37   statefail = std::ios_base::failbit;
  38   stateeof = std::ios_base::eofbit;
  39
  40   // string str() const
  41   str02 = is01.str();
  42   VERIFY( str00 == str02 );
  43
  44   // void str(const basic_string&)
  45   is01.str(str01);
  46   str02 = is01.str();
  47   VERIFY( str01 == str02 );
  48   state1 = is01.rdstate();
  49   is01 >> a;
  50   state2 = is01.rdstate();
  51   VERIFY( a = i01 );
  52   // 22.2.2.1.2 num_get virtual functions
  53   // p 13
  54   // in any case, if stage 2 processing was terminated by the test for
  55   // in == end then err != ios_base::eofbit is performed.
  56   VERIFY( state1 != state2 );
  57   VERIFY( state2 == stateeof );
  58
  59   is01.str(str01);
  60   is01 >> b;
  61   VERIFY( b != a );
  62   // as is01.good() is false, istream::sentry blocks extraction.
  63
  64   is01.clear();
  65   state1 = is01.rdstate();
  66   is01 >> b;
  67   state2 = is01.rdstate();
  68   VERIFY( b == a );
  69   VERIFY( state1 != state2 );
  70   VERIFY( state2 == stateeof );
  71
  72  #ifdef DEBUG_ASSERT
  73   assert(test);
  74 #endif
  75 }
  76
  77 void
  78 redirect_buffer(std::ios& stream, std::streambuf* new_buf)
  79 { stream.rdbuf(new_buf); }
  80
  81 std::streambuf*
  82 active_buffer(std::ios& stream)
  83 { return stream.rdbuf(); }
  84
  85 // libstdc++/2832
  86 void test02()
  87 {
  88   bool test = true;
  89   const char* strlit01 = "fuck war";
  90   const char* strlit02 = "two less cars abstract riot crew, critical mass/SF";
  91   const std::string str00;
  92   const std::string str01(strlit01);
  93   std::string str02;
  94   std::stringbuf sbuf(str01);
  95   std::streambuf* pbasebuf0 = &sbuf;
  96
  97   std::istringstream sstrm1;
  98   VERIFY( sstrm1.str() == str00 );
  99   // derived rdbuf() always returns original streambuf, even though
 100   // it's no longer associated with the stream.
 101   std::stringbuf* const buf1 = sstrm1.rdbuf();
 102   // base rdbuf() returns the currently associated streambuf
 103   std::streambuf* pbasebuf1 = active_buffer(sstrm1);
 104   redirect_buffer(sstrm1, &sbuf);
 105   std::stringbuf* const buf2 = sstrm1.rdbuf();
 106   std::streambuf* pbasebuf2 = active_buffer(sstrm1);
 107   VERIFY( buf1 == buf2 );
 108   VERIFY( pbasebuf1 != pbasebuf2 );
 109   VERIFY( pbasebuf2 == pbasebuf0 );
 110
 111   // derived rdbuf() returns the original buf, so str() doesn't change.
 112   VERIFY( sstrm1.str() != str01 );
 113   VERIFY( sstrm1.str() == str00 );
 114   // however, casting the active streambuf to a stringbuf shows what's up:
 115   std::stringbuf* psbuf = dynamic_cast<std::stringbuf*>(pbasebuf2);
 116   str02 = psbuf->str();
 117   VERIFY( str02 == str01 );
 118
 119   // How confusing and non-intuitive is this?
 120   // These semantics are a joke, a serious defect, and incredibly lame.
 121 }
 122
 123 int main()
 124 {
 125   test01();
 126   test02();
 127   return 0;
 128 }
 129
 130
 131