libcxx/test/input.output/file.streams/fstreams/filebuf.assign/nonmember_swap.pass.cpp

//===----------------------------------------------------------------------===//
//
//                     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.
//
//===----------------------------------------------------------------------===//

// <fstream>

// template <class charT, class traits = char_traits<charT> >
// class basic_filebuf

// template <class charT, class traits>
// void
// swap(basic_filebuf<charT, traits>& x, basic_filebuf<charT, traits>& y);

#include <fstream>
#include <cassert>

int main()
{
    {
        std::filebuf f;
        assert(f.open("test.dat", std::ios_base::out | std::ios_base::in
                                                     | std::ios_base::trunc) != 0);
        assert(f.is_open());
        assert(f.sputn("123", 3) == 3);
        f.pubseekoff(1, std::ios_base::beg);
        assert(f.sgetc() == '2');
        std::filebuf f2;
        swap(f2, f);
        assert(!f.is_open());
        assert(f2.is_open());
        assert(f2.sgetc() == '2');
    }
    remove("test.dat");
    {
        std::wfilebuf f;
        assert(f.open("test.dat", std::ios_base::out | std::ios_base::in
                                                     | std::ios_base::trunc) != 0);
        assert(f.is_open());
        assert(f.sputn(L"123", 3) == 3);
        f.pubseekoff(1, std::ios_base::beg);
        assert(f.sgetc() == L'2');
        std::wfilebuf f2;
        swap(f2, f);
        assert(!f.is_open());
        assert(f2.is_open());
        assert(f2.sgetc() == L'2');
    }
    remove("test.dat");
}