libcxx/test/std/input.output/iostream.format/output.streams/ostream.rvalue/rvalue.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 // <ostream>
  10
  11 // template <class Stream, class T>
  12 // Stream&& operator<<(Stream&& os, const T& x);
  13
  14 #include <ostream>
  15 #include <cassert>
  16
  17 #include "test_macros.h"
  18
  19
  20 template <class CharT>
  21 class testbuf
  22     : public std::basic_streambuf<CharT>
  23 {
  24     typedef std::basic_streambuf<CharT> base;
  25     std::basic_string<CharT> str_;
  26 public:
  27     testbuf()
  28     {
  29     }
  30
  31     std::basic_string<CharT> str() const
  32         {return std::basic_string<CharT>(base::pbase(), base::pptr());}
  33
  34 protected:
  35
  36     virtual typename base::int_type
  37         overflow(typename base::int_type ch = base::traits_type::eof())
  38         {
  39             if (ch != base::traits_type::eof())
  40             {
  41                 int n = static_cast<int>(str_.size());
  42                 str_.push_back(static_cast<CharT>(ch));
  43                 str_.resize(str_.capacity());
  44                 base::setp(const_cast<CharT*>(str_.data()),
  45                            const_cast<CharT*>(str_.data() + str_.size()));
  46                 base::pbump(n+1);
  47             }
  48             return ch;
  49         }
  50 };
  51
  52 struct Int {
  53     int value;
  54     template <class CharT>
  55     friend void operator<<(std::basic_ostream<CharT>& os, Int const& self) {
  56         os << self.value;
  57     }
  58 };
  59
  60 int main(int, char**)
  61 {
  62     {
  63         testbuf<char> sb;
  64         std::ostream os(&sb);
  65         Int const i = {123};
  66         std::ostream&& result = (std::move(os) << i);
  67         assert(&result == &os);
  68         assert(sb.str() == "123");
  69     }
  70 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  71     {
  72         testbuf<wchar_t> sb;
  73         std::wostream os(&sb);
  74         Int const i = {123};
  75         std::wostream&& result = (std::move(os) << i);
  76         assert(&result == &os);
  77         assert(sb.str() == L"123");
  78     }
  79 #endif
  80
  81     return 0;
  82 }