construct.pass.cpp revision 72215c2dbf0bbff4ad9f73879d346be95facdd83 
1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <ostream>
11
12// template <class charT, class traits = char_traits<charT> >
13// class basic_ostream::sentry;
14
15// explicit sentry(basic_ostream<charT,traits>& os);
16
17#include <ostream>
18#include <cassert>
19
20int sync_called = 0;
21
22template <class CharT>
23struct testbuf1
24    : public std::basic_streambuf<CharT>
25{
26    testbuf1() {}
27
28protected:
29
30    int virtual sync()
31    {
32        ++sync_called;
33        return 1;
34    }
35};
36
37int main()
38{
39    {
40        std::ostream os((std::streambuf*)0);
41        std::ostream::sentry s(os);
42        assert(!bool(s));
43    }
44    {
45        testbuf1<char> sb;
46        std::ostream os(&sb);
47        std::ostream::sentry s(os);
48        assert(bool(s));
49    }
50    {
51        testbuf1<char> sb;
52        std::ostream os(&sb);
53        testbuf1<char> sb2;
54        std::ostream os2(&sb2);
55        os.tie(&os2);
56        assert(sync_called == 0);
57        std::ostream::sentry s(os);
58        assert(bool(s));
59        assert(sync_called == 1);
60    }
61}
62