#define BOOST_TEST_MODULE nonblocking_indirect_streambuf_write

#include <boost/algorithm/string/predicate.hpp>
#include <boost/iostreams/categories.hpp>
#include <boost/iostreams/filtering_stream.hpp>
#include <boost/test/included/unit_test.hpp>

struct sink
{
public:
    typedef char char_type;
    typedef boost::iostreams::sink_tag category;

    sink()
        : state_(0)
    { }

    ~sink()
    {
        BOOST_REQUIRE_EQUAL(state_, 4);
    }

    std::streamsize write(const char* in, std::streamsize n)
    {
        BOOST_REQUIRE_GE(n, 2);
        switch(state_++)
        {
        case 0:
            BOOST_REQUIRE_EQUAL(std::string(in, 2), "AB"); break;
        case 1:
            BOOST_REQUIRE_EQUAL(std::string(in, 2), "CD"); break;
        case 2:
            BOOST_REQUIRE_EQUAL(std::string(in, 2), "EF"); break;
        case 3:
            BOOST_REQUIRE_EQUAL(std::string(in, 2), "GH"); break;
        default:
            BOOST_FAIL("'write' called too many times!");
        }
        return 2;
    }

    size_t state_;
};

BOOST_AUTO_TEST_CASE(nonblocking_indirect_streambuf_write)
{
    boost::iostreams::filtering_ostream ostream;
    ostream.push((sink()));

    ostream << "ABCDEFGH";
    ostream.flush();
}