test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ostream.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is dual licensed under the MIT and the University of Illinois Open
   6 // Source Licenses. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 // <ostream>
  11
  12 // template <class charT, class traits = char_traits<charT> >
  13 //   class basic_ostream;
  14
  15 // basic_ostream<charT,traits>& operator<<
  16 //           (basic_ostream<charT,traits>& (*pf)(basic_ostream<charT,traits>&))
  17
  18 #include <ostream>
  19 #include <cassert>
  20
  21 template <class CharT>
  22 class testbuf
  23     : public std::basic_streambuf<CharT>
  24 {
  25     typedef std::basic_streambuf<CharT> base;
  26     std::basic_string<CharT> str_;
  27 public:
  28     testbuf()
  29     {
  30     }
  31
  32     std::basic_string<CharT> str() const
  33         {return std::basic_string<CharT>(base::pbase(), base::pptr());}
  34
  35 protected:
  36
  37     virtual typename base::int_type
  38         overflow(typename base::int_type __c = base::traits_type::eof())
  39         {
  40             if (__c != base::traits_type::eof())
  41             {
  42                 int n = static_cast<int>(str_.size());
  43                 str_.push_back(static_cast<CharT>(__c));
  44                 str_.resize(str_.capacity());
  45                 base::setp(const_cast<CharT*>(str_.data()),
  46                            const_cast<CharT*>(str_.data() + str_.size()));
  47                 base::pbump(n+1);
  48             }
  49             return __c;
  50         }
  51 };
  52
  53 template <class CharT>
  54 std::basic_ostream<CharT>&
  55 f(std::basic_ostream<CharT>& os)
  56 {
  57     os << "testing...";
  58     return os;
  59 }
  60
  61 int main()
  62 {
  63     {
  64         testbuf<char> sb;
  65         std::ostream os(&sb);
  66         os << f;
  67         assert(sb.str() == "testing...");
  68     }
  69 }