1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // FILE_DEPENDENCIES: underflow.dat
10 
11 // <locale>
12 
13 // wbuffer_convert<Codecvt, Elem, Tr>
14 
15 // int_type pbackfail(int_type c = traits::eof());
16 
17 // This test is not entirely portable
18 
19 #include <locale>
20 #include <codecvt>
21 #include <fstream>
22 #include <cassert>
23 
24 #include "test_macros.h"
25 
26 struct test_buf
27     : public std::wbuffer_convert<std::codecvt_utf8<wchar_t> >
28 {
29     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > base;
30     typedef base::char_type   char_type;
31     typedef base::int_type    int_type;
32     typedef base::traits_type traits_type;
33 
test_buftest_buf34     explicit test_buf(std::streambuf* sb) : base(sb) {}
35 
ebacktest_buf36     char_type* eback() const {return base::eback();}
gptrtest_buf37     char_type* gptr()  const {return base::gptr();}
egptrtest_buf38     char_type* egptr() const {return base::egptr();}
gbumptest_buf39     void gbump(int n) {base::gbump(n);}
40 
pbackfailtest_buf41     virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
42 };
43 
main(int,char **)44 int main(int, char**)
45 {
46     {
47         std::ifstream bs("underflow.dat");
48         test_buf f(bs.rdbuf());
49         assert(f.sbumpc() == L'1');
50         assert(f.sgetc() == L'2');
51         assert(f.pbackfail(L'a') == test_buf::traits_type::eof());
52     }
53     {
54         std::fstream bs("underflow.dat");
55         test_buf f(bs.rdbuf());
56         assert(f.sbumpc() == L'1');
57         assert(f.sgetc() == L'2');
58         assert(f.pbackfail(L'a') == test_buf::traits_type::eof());
59         assert(f.sbumpc() == L'2');
60         assert(f.sgetc() == L'3');
61     }
62 
63   return 0;
64 }
65