xref: /llvm-project/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp (revision 4dee6411e0d993fd17099bd7564276474412383e)
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 // UNSUPPORTED: c++03, c++11, c++14
10 
11 // UNSUPPORTED: availability-filesystem-missing
12 
13 // FILE_DEPENDENCIES: test.dat
14 
15 // <fstream>
16 
17 // template <class charT, class traits = char_traits<charT> >
18 // class basic_ifstream
19 
20 // template<class T>
21 // explicit basic_ifstream(const T& s, ios_base::openmode mode = ios_base::in); // Since C++17
22 // Constraints: is_same_v<T, filesystem::path> is true
23 
24 #include <cassert>
25 #include <filesystem>
26 #include <fstream>
27 #include <type_traits>
28 
29 #include "test_macros.h"
30 #include "test_iterators.h"
31 #include "operator_hijacker.h"
32 
33 namespace fs = std::filesystem;
34 
35 template <class CharT>
36 constexpr bool test_non_convert_to_path() {
37   // String types
38   static_assert(!std::is_constructible_v<std::ifstream, std::basic_string_view<CharT>>);
39   static_assert(!std::is_constructible_v<std::ifstream, const std::basic_string_view<CharT>>);
40 
41   // Char* pointers
42   if constexpr (!std::is_same_v<CharT, char> && !std::is_same_v<CharT, fs::path::value_type>)
43     static_assert(!std::is_constructible_v<std::ifstream, const CharT*>);
44 
45   // Iterators
46   static_assert(!std::is_convertible_v<std::ifstream, cpp17_input_iterator<const CharT*>>);
47 
48   return true;
49 }
50 
51 static_assert(test_non_convert_to_path<char>());
52 
53 #if !defined(TEST_HAS_NO_WIDE_CHARACTERS) && !defined(TEST_HAS_OPEN_WITH_WCHAR)
54 static_assert(test_non_convert_to_path<wchar_t>());
55 #endif // !TEST_HAS_NO_WIDE_CHARACTERS && !TEST_HAS_OPEN_WITH_WCHAR
56 
57 #ifndef TEST_HAS_NO_CHAR8_T
58 static_assert(test_non_convert_to_path<char8_t>());
59 #endif // TEST_HAS_NO_CHAR8_T
60 
61 static_assert(test_non_convert_to_path<char16_t>());
62 static_assert(test_non_convert_to_path<char32_t>());
63 
64 int main(int, char**) {
65   {
66     fs::path p;
67     static_assert(!std::is_convertible<fs::path, std::ifstream>::value,
68                   "ctor should be explicit");
69     static_assert(std::is_constructible<std::ifstream, fs::path const&,
70                                         std::ios_base::openmode>::value,
71                   "");
72   }
73   {
74     std::ifstream fs(fs::path("test.dat"));
75     double x = 0;
76     fs >> x;
77     assert(x == 3.25);
78   }
79   {
80     std::basic_ifstream<char, operator_hijacker_char_traits<char>> fs(fs::path("test.dat"));
81     std::basic_string<char, operator_hijacker_char_traits<char> > x;
82     fs >> x;
83     assert(x == "3.25");
84   }
85   // std::ifstream(const fs::path&, std::ios_base::openmode) is tested in
86   // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
87   // which creates writable files.
88 
89 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
90   {
91     std::wifstream fs(fs::path("test.dat"));
92     double x = 0;
93     fs >> x;
94     assert(x == 3.25);
95   }
96   {
97     std::basic_ifstream<wchar_t, operator_hijacker_char_traits<wchar_t> > fs(fs::path("test.dat"));
98     std::basic_string<wchar_t, operator_hijacker_char_traits<wchar_t> > x;
99     fs >> x;
100     assert(x == L"3.25");
101   }
102   // std::wifstream(const fs::path&, std::ios_base::openmode) is tested in
103   // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
104   // which creates writable files.
105 #endif
106 
107   return 0;
108 }
109