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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <ostream>
// template <class charT, class traits = char_traits<charT> >
// class basic_ostream;
// template<class charT, class traits>
// basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>& out, charT c);
#include <ostream>
#include <cassert>
template <class CharT>
class testbuf
: public std::basic_streambuf<CharT>
{
typedef std::basic_streambuf<CharT> base;
std::basic_string<CharT> str_;
public:
testbuf()
{
}
std::basic_string<CharT> str() const
{return std::basic_string<CharT>(base::pbase(), base::pptr());}
protected:
virtual typename base::int_type
overflow(typename base::int_type ch = base::traits_type::eof())
{
if (ch != base::traits_type::eof())
{
int n = static_cast<int>(str_.size());
str_.push_back(ch);
str_.resize(str_.capacity());
base::setp(const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data() + str_.size()));
base::pbump(n+1);
}
return ch;
}
};
int main()
{
{
std::wostream os((std::wstreambuf*)0);
wchar_t c = L'a';
os << c;
assert(os.bad());
assert(os.fail());
}
{
testbuf<wchar_t> sb;
std::wostream os(&sb);
wchar_t c = L'a';
os << c;
assert(sb.str() == L"a");
}
{
testbuf<wchar_t> sb;
std::wostream os(&sb);
os.width(5);
wchar_t c = L'a';
os << c;
assert(sb.str() == L" a");
assert(os.width() == 0);
}
{
testbuf<wchar_t> sb;
std::wostream os(&sb);
os.width(5);
left(os);
wchar_t c = L'a';
os << c;
assert(sb.str() == L"a ");
assert(os.width() == 0);
}
}
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