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 // <sstream>
10 
11 // template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
12 // class basic_stringbuf
13 
14 // int_type overflow(int_type c = traits::eof());
15 
16 #include <sstream>
17 #include <cassert>
18 
19 int overflow_called = 0;
20 
21 template <class CharT>
22 struct testbuf
23     : public std::basic_stringbuf<CharT>
24 {
25     typedef std::basic_stringbuf<CharT> base;
26     explicit testbuf(const std::basic_string<CharT>& str,
27                      std::ios_base::openmode which = std::ios_base::in | std::ios_base::out)
28         : base(str, which) {}
29 
30     typename base::int_type
31         overflow(typename base::int_type c = base::traits_type::eof())
32         {++overflow_called; return base::overflow(c);}
33 
34     void pbump(int n) {base::pbump(n);}
35 };
36 
37 int main(int, char**)
38 {
39     {  // sanity check
40     testbuf<char> tb("");
41     tb.overflow();
42     }
43     {
44         testbuf<char> sb("abc");
45         assert(sb.sputc('1') == '1');
46         assert(sb.str() == "1bc");
47         assert(sb.sputc('2') == '2');
48         assert(sb.str() == "12c");
49         assert(sb.sputc('3') == '3');
50         assert(sb.str() == "123");
51         assert(sb.sputc('4') == '4');
52         assert(sb.str() == "1234");
53         assert(sb.sputc('5') == '5');
54         assert(sb.str() == "12345");
55         assert(sb.sputc('6') == '6');
56         assert(sb.str() == "123456");
57         assert(sb.sputc('7') == '7');
58         assert(sb.str() == "1234567");
59         assert(sb.sputc('8') == '8');
60         assert(sb.str() == "12345678");
61         assert(sb.sputc('9') == '9');
62         assert(sb.str() == "123456789");
63         assert(sb.sputc('0') == '0');
64         assert(sb.str() == "1234567890");
65         assert(sb.sputc('1') == '1');
66         assert(sb.str() == "12345678901");
67     }
68     {
69         testbuf<wchar_t> sb(L"abc");
70         assert(sb.sputc(L'1') == L'1');
71         assert(sb.str() == L"1bc");
72         assert(sb.sputc(L'2') == L'2');
73         assert(sb.str() == L"12c");
74         assert(sb.sputc(L'3') == L'3');
75         assert(sb.str() == L"123");
76         assert(sb.sputc(L'4') == L'4');
77         assert(sb.str() == L"1234");
78         assert(sb.sputc(L'5') == L'5');
79         assert(sb.str() == L"12345");
80         assert(sb.sputc(L'6') == L'6');
81         assert(sb.str() == L"123456");
82         assert(sb.sputc(L'7') == L'7');
83         assert(sb.str() == L"1234567");
84         assert(sb.sputc(L'8') == L'8');
85         assert(sb.str() == L"12345678");
86         assert(sb.sputc(L'9') == L'9');
87         assert(sb.str() == L"123456789");
88         assert(sb.sputc(L'0') == L'0');
89         assert(sb.str() == L"1234567890");
90         assert(sb.sputc(L'1') == L'1');
91         assert(sb.str() == L"12345678901");
92     }
93     {
94         testbuf<char> sb("abc", std::ios_base::app | std::ios_base::out);
95         assert(sb.sputc('1') == '1');
96         assert(sb.str() == "abc1");
97         assert(sb.sputc('2') == '2');
98         assert(sb.str() == "abc12");
99     }
100 
101   return 0;
102 }
103