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 // <fstream>
10 
11 // template <class charT, class traits = char_traits<charT> >
12 // class basic_ifstream
13 
14 // void open(const char* s, ios_base::openmode mode = ios_base::in);
15 
16 #include <fstream>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
21 int main(int, char**)
22 {
23     {
24         std::ifstream fs;
25         assert(!fs.is_open());
26         char c = 'a';
27         fs >> c;
28         assert(fs.fail());
29         assert(c == 'a');
30         fs.open("test.dat");
31         assert(fs.is_open());
32         fs >> c;
33         assert(c == 'r');
34     }
35     {
36         std::wifstream fs;
37         assert(!fs.is_open());
38         wchar_t c = L'a';
39         fs >> c;
40         assert(fs.fail());
41         assert(c == L'a');
42         fs.open("test.dat");
43         assert(fs.is_open());
44         fs >> c;
45         assert(c == L'r');
46     }
47 
48   return 0;
49 }
50