1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <locale>
11
12// wbuffer_convert<Codecvt, Elem, Tr>
13
14// int_type underflow();
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 underflow() {return base::underflow();}
39};
40
41int main()
42{
43    {
44        std::ifstream bs("underflow.dat");
45        test_buf f(bs.rdbuf());
46        assert(f.eback() == 0);
47        assert(f.gptr() == 0);
48        assert(f.egptr() == 0);
49        assert(f.underflow() == L'1');
50        assert(f.eback() != 0);
51        assert(f.eback() == f.gptr());
52        assert(*f.gptr() == L'1');
53        assert(f.egptr() - f.eback() == 9);
54    }
55    {
56        std::ifstream bs("underflow.dat");
57        test_buf f(bs.rdbuf());
58        assert(f.eback() == 0);
59        assert(f.gptr() == 0);
60        assert(f.egptr() == 0);
61        assert(f.underflow() == L'1');
62        assert(f.eback() != 0);
63        assert(f.eback() == f.gptr());
64        assert(*f.gptr() == L'1');
65        assert(f.egptr() - f.eback() == 9);
66        f.gbump(8);
67        assert(f.sgetc() == L'9');
68        assert(f.eback()[0] == L'1');
69        assert(f.eback()[1] == L'2');
70        assert(f.eback()[2] == L'3');
71        assert(f.eback()[3] == L'4');
72        assert(f.gptr() - f.eback() == 8);
73        assert(*f.gptr() == L'9');
74        assert(f.egptr() - f.gptr() == 1);
75    }
76    {
77        std::ifstream bs("underflow_utf8.dat");
78        test_buf f(bs.rdbuf());
79        assert(f.sbumpc() == 0x4E51);
80        assert(f.sbumpc() == 0x4E52);
81        assert(f.sbumpc() == 0x4E53);
82        assert(f.sbumpc() == test_buf::traits_type::eof());
83    }
84}
85