pbackfail.pass.cpp revision f5256e16dfc425c1d466f6308d4026d529ce9e0b 
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// <sstream>
11
12// template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
13// class basic_stringbuf
14
15// int_type pbackfail(int_type c = traits::eof());
16
17#include <sstream>
18#include <cassert>
19
20template <class CharT>
21struct testbuf
22    : public std::basic_stringbuf<CharT>
23{
24    typedef std::basic_stringbuf<CharT> base;
25    explicit testbuf(const std::basic_string<CharT>& str,
26                     std::ios_base::openmode which = std::ios_base::in | std::ios_base::out)
27        : base(str, which) {}
28
29    typename base::int_type
30        pbackfail(typename base::int_type c = base::type_traits::eof())
31        {return base::pbackfail(c);}
32
33    void pbump(int n) {base::pbump(n);}
34};
35
36int main()
37{
38    {
39        testbuf<char> sb("123", std::ios_base::in);
40        assert(sb.sgetc() == '1');
41        assert(sb.snextc() == '2');
42        assert(sb.snextc() == '3');
43        assert(sb.sgetc() == '3');
44        assert(sb.snextc() == std::char_traits<char>::eof());
45        assert(sb.pbackfail('3') == '3');
46        assert(sb.pbackfail('3') == std::char_traits<char>::eof());
47        assert(sb.pbackfail('2') == '2');
48        assert(sb.pbackfail(std::char_traits<char>::eof()) != std::char_traits<char>::eof());
49        assert(sb.pbackfail(std::char_traits<char>::eof()) == std::char_traits<char>::eof());
50        assert(sb.str() == "123");
51    }
52    {
53        testbuf<char> sb("123");
54        assert(sb.sgetc() == '1');
55        assert(sb.snextc() == '2');
56        assert(sb.snextc() == '3');
57        assert(sb.sgetc() == '3');
58        assert(sb.snextc() == std::char_traits<char>::eof());
59        assert(sb.pbackfail('3') == '3');
60        assert(sb.pbackfail('3') == '3');
61        assert(sb.pbackfail(std::char_traits<char>::eof()) != std::char_traits<char>::eof());
62        assert(sb.pbackfail(std::char_traits<char>::eof()) == std::char_traits<char>::eof());
63        assert(sb.str() == "133");
64    }
65    {
66        testbuf<wchar_t> sb(L"123", std::ios_base::in);
67        assert(sb.sgetc() == L'1');
68        assert(sb.snextc() == L'2');
69        assert(sb.snextc() == L'3');
70        assert(sb.sgetc() == L'3');
71        assert(sb.snextc() == std::char_traits<wchar_t>::eof());
72        assert(sb.pbackfail(L'3') == L'3');
73        assert(sb.pbackfail(L'3') == std::char_traits<wchar_t>::eof());
74        assert(sb.pbackfail(L'2') == L'2');
75        assert(sb.pbackfail(std::char_traits<wchar_t>::eof()) != std::char_traits<wchar_t>::eof());
76        assert(sb.pbackfail(std::char_traits<wchar_t>::eof()) == std::char_traits<wchar_t>::eof());
77        assert(sb.str() == L"123");
78    }
79    {
80        testbuf<wchar_t> sb(L"123");
81        assert(sb.sgetc() == L'1');
82        assert(sb.snextc() == L'2');
83        assert(sb.snextc() == L'3');
84        assert(sb.sgetc() == L'3');
85        assert(sb.snextc() == std::char_traits<wchar_t>::eof());
86        assert(sb.pbackfail(L'3') == L'3');
87        assert(sb.pbackfail(L'3') == L'3');
88        assert(sb.pbackfail(std::char_traits<wchar_t>::eof()) != std::char_traits<wchar_t>::eof());
89        assert(sb.pbackfail(std::char_traits<wchar_t>::eof()) == std::char_traits<wchar_t>::eof());
90        assert(sb.str() == L"133");
91    }
92}
93