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 
23 struct 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 
test_buftest_buf31     explicit test_buf(std::streambuf* sb) : base(sb) {}
32 
ebacktest_buf33     char_type* eback() const {return base::eback();}
gptrtest_buf34     char_type* gptr()  const {return base::gptr();}
egptrtest_buf35     char_type* egptr() const {return base::egptr();}
gbumptest_buf36     void gbump(int n) {base::gbump(n);}
37 
underflowtest_buf38     virtual int_type underflow() {return base::underflow();}
39 };
40 
main()41 int 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