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 // XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
10 
11 // <istream>
12 
13 // int_type get();
14 
15 #include <istream>
16 #include <cassert>
17 #include "test_macros.h"
18 
19 template <class CharT>
20 struct testbuf
21     : public std::basic_streambuf<CharT>
22 {
23     typedef std::basic_string<CharT> string_type;
24     typedef std::basic_streambuf<CharT> base;
25 private:
26     string_type str_;
27 public:
28 
29     testbuf() {}
30     testbuf(const string_type& str)
31         : str_(str)
32     {
33         base::setg(const_cast<CharT*>(str_.data()),
34                    const_cast<CharT*>(str_.data()),
35                    const_cast<CharT*>(str_.data()) + str_.size());
36     }
37 
38     CharT* eback() const {return base::eback();}
39     CharT* gptr() const {return base::gptr();}
40     CharT* egptr() const {return base::egptr();}
41 };
42 
43 int main(int, char**)
44 {
45     {
46         testbuf<char> sb("          ");
47         std::istream is(&sb);
48         char c = static_cast<char>(is.get());
49         assert(!is.eof());
50         assert(!is.fail());
51         assert(c == ' ');
52         assert(is.gcount() == 1);
53     }
54     {
55         testbuf<char> sb(" abc");
56         std::istream is(&sb);
57         char c = static_cast<char>(is.get());
58         assert(!is.eof());
59         assert(!is.fail());
60         assert(c == ' ');
61         assert(is.gcount() == 1);
62         c = static_cast<char>(is.get());
63         assert(!is.eof());
64         assert(!is.fail());
65         assert(c == 'a');
66         assert(is.gcount() == 1);
67         c = static_cast<char>(is.get());
68         assert(!is.eof());
69         assert(!is.fail());
70         assert(c == 'b');
71         assert(is.gcount() == 1);
72         c = static_cast<char>(is.get());
73         assert(!is.eof());
74         assert(!is.fail());
75         assert(c == 'c');
76         assert(is.gcount() == 1);
77     }
78 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
79     {
80         testbuf<wchar_t> sb(L" abc");
81         std::wistream is(&sb);
82         wchar_t c = is.get();
83         assert(!is.eof());
84         assert(!is.fail());
85         assert(c == L' ');
86         assert(is.gcount() == 1);
87         c = is.get();
88         assert(!is.eof());
89         assert(!is.fail());
90         assert(c == L'a');
91         assert(is.gcount() == 1);
92         c = is.get();
93         assert(!is.eof());
94         assert(!is.fail());
95         assert(c == L'b');
96         assert(is.gcount() == 1);
97         c = is.get();
98         assert(!is.eof());
99         assert(!is.fail());
100         assert(c == L'c');
101         assert(is.gcount() == 1);
102     }
103 #endif
104 #ifndef TEST_HAS_NO_EXCEPTIONS
105     {
106         testbuf<char> sb("rrrrrrrrr");
107         std::basic_istream<char> is(&sb);
108         is.exceptions(std::ios_base::eofbit);
109 
110         bool threw = false;
111         try {
112             while (true) {
113                 is.get();
114                 if (is.eof())
115                     break;
116             }
117         } catch (std::ios_base::failure const&) {
118             threw = true;
119         }
120 
121         assert(!is.bad());
122         assert( is.fail());
123         assert( is.eof());
124         assert(threw);
125     }
126 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
127     {
128         testbuf<wchar_t> sb(L"rrrrrrrrr");
129         std::basic_istream<wchar_t> is(&sb);
130         is.exceptions(std::ios_base::eofbit);
131 
132         bool threw = false;
133         try {
134             while (true) {
135                 is.get();
136                 if (is.eof())
137                     break;
138             }
139         } catch (std::ios_base::failure const&) {
140             threw = true;
141         }
142 
143         assert(!is.bad());
144         assert( is.fail());
145         assert( is.eof());
146         assert(threw);
147     }
148 #endif
149 #endif // TEST_HAS_NO_EXCEPTIONS
150 
151     return 0;
152 }
153