pbackfail.pass.cpp revision 4b53f508efcd857b2dddeff092a8509def5bc6bd 
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// <locale>
11
12// wbuffer_convert<Codecvt, Elem, Tr>
13
14// int_type pbackfail(int_type c = traits::eof());
15
16// This test is not entirely portable
17
18#include <locale>
19#include <codecvt>
20#include <fstream>
21#include <cassert>
22
23struct test_buf
24    : public std::wbuffer_convert<std::codecvt_utf8<wchar_t> >
25{
26    typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > base;
27    typedef base::char_type   char_type;
28    typedef base::int_type    int_type;
29    typedef base::traits_type traits_type;
30
31    explicit test_buf(std::streambuf* sb) : base(sb) {}
32
33    char_type* eback() const {return base::eback();}
34    char_type* gptr()  const {return base::gptr();}
35    char_type* egptr() const {return base::egptr();}
36    void gbump(int n) {base::gbump(n);}
37
38    virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
39};
40
41int main()
42{
43    {
44        std::ifstream bs("underflow.dat");
45        test_buf f(bs.rdbuf());
46        assert(f.sbumpc() == L'1');
47        assert(f.sgetc() == L'2');
48        assert(f.pbackfail(L'a') == -1);
49    }
50    {
51        std::fstream bs("underflow.dat");
52        test_buf f(bs.rdbuf());
53        assert(f.sbumpc() == L'1');
54        assert(f.sgetc() == L'2');
55        assert(f.pbackfail(L'a') == -1);
56        assert(f.sbumpc() == L'2');
57        assert(f.sgetc() == L'3');
58    }
59}
60