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
10
11 // <iomanip>
12
13 // std::quoted
14 // Verify that the result type of std::quoted can be streamed to
15 // (and from) ostreams with the correct CharTraits, and not those
16 // with the wrong CharTraits. To avoid our having to create working
17 // ostreams with weird CharTraits, this is a compile-only test.
18
19 #include <iomanip>
20 #include <istream>
21 #include <ostream>
22 #include <string>
23 #include <string_view>
24 #include <type_traits>
25
26 #include "test_allocator.h"
27 #include "test_macros.h"
28
29 template<class IS, class Q>
30 decltype(std::declval<IS>() >> std::declval<Q>(), std::true_type())
has_rightshift_impl(int)31 has_rightshift_impl(int) { return std::true_type(); }
32
33 template<class IS, class Q>
34 std::false_type
has_rightshift_impl(long)35 has_rightshift_impl(long) { return std::false_type(); }
36
37 template<class IS, class Q>
38 struct HasRightShift : decltype(has_rightshift_impl<IS, Q>(0)) {};
39
40 template<class OS, class Q>
41 decltype(std::declval<OS>() << std::declval<Q>(), std::true_type())
has_leftshift_impl(int)42 has_leftshift_impl(int) { return std::true_type(); }
43
44 template<class OS, class Q>
45 std::false_type
has_leftshift_impl(long)46 has_leftshift_impl(long) { return std::false_type(); }
47
48 template<class OS, class Q>
49 struct HasLeftShift : decltype(has_leftshift_impl<OS, Q>(0)) {};
50
51 template<class CharT>
52 struct FakeCharTraits : std::char_traits<CharT> {};
53
test_string_literal()54 void test_string_literal()
55 {
56 using Q = decltype(std::quoted("hello"));
57 static_assert( HasLeftShift<std::ostream&, Q>::value, "");
58 static_assert(!HasRightShift<std::istream&, Q>::value, "");
59 static_assert( HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, Q>::value, "");
60 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, Q>::value, "");
61
62 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
63 using WQ = decltype(std::quoted(L"hello"));
64 static_assert( HasLeftShift<std::wostream&, WQ>::value, "");
65 static_assert(!HasRightShift<std::wistream&, WQ>::value, "");
66 static_assert( HasLeftShift<std::basic_ostream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
67 static_assert(!HasRightShift<std::basic_istream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
68
69 static_assert(!HasLeftShift<std::ostream&, WQ>::value, "");
70 static_assert(!HasLeftShift<std::wostream&, Q>::value, "");
71 #endif // TEST_HAS_NO_WIDE_CHARACTERS
72 }
73
test_std_string()74 void test_std_string()
75 {
76 std::string s = "hello";
77 const auto& cs = s;
78 using Q = decltype(std::quoted(s));
79 using CQ = decltype(std::quoted(cs));
80 static_assert( HasLeftShift<std::ostream&, Q>::value, "");
81 static_assert( HasRightShift<std::istream&, Q>::value, "");
82 static_assert( HasLeftShift<std::ostream&, CQ>::value, "");
83 static_assert(!HasRightShift<std::istream&, CQ>::value, "");
84 static_assert(!HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, Q>::value, "");
85 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, Q>::value, "");
86 static_assert(!HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, CQ>::value, "");
87 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, CQ>::value, "");
88
89 std::basic_string<char, FakeCharTraits<char>, test_allocator<char>> st = "hello";
90 const auto& cst = st;
91 using QT = decltype(std::quoted(st));
92 using CQT = decltype(std::quoted(cst));
93 static_assert(!HasLeftShift<std::ostream&, QT>::value, "");
94 static_assert(!HasRightShift<std::istream&, QT>::value, "");
95 static_assert(!HasLeftShift<std::ostream&, CQT>::value, "");
96 static_assert(!HasRightShift<std::istream&, CQT>::value, "");
97 static_assert( HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, QT>::value, "");
98 static_assert( HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, QT>::value, "");
99 static_assert( HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, CQT>::value, "");
100 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, CQT>::value, "");
101
102 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
103 std::wstring ws = L"hello";
104 const auto& cws = ws;
105 using WQ = decltype(std::quoted(ws));
106 using CWQ = decltype(std::quoted(cws));
107 static_assert( HasLeftShift<std::wostream&, WQ>::value, "");
108 static_assert( HasRightShift<std::wistream&, WQ>::value, "");
109 static_assert( HasLeftShift<std::wostream&, CWQ>::value, "");
110 static_assert(!HasRightShift<std::wistream&, CWQ>::value, "");
111 static_assert(!HasLeftShift<std::basic_ostream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
112 static_assert(!HasRightShift<std::basic_istream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
113 static_assert(!HasLeftShift<std::basic_ostream<wchar_t, FakeCharTraits<wchar_t>>&, CWQ>::value, "");
114 static_assert(!HasRightShift<std::basic_istream<wchar_t, FakeCharTraits<wchar_t>>&, CWQ>::value, "");
115
116 static_assert(!HasLeftShift<std::ostream&, WQ>::value, "");
117 static_assert(!HasLeftShift<std::wostream&, Q>::value, "");
118 #endif // TEST_HAS_NO_WIDE_CHARACTERS
119 }
120
test_std_string_view()121 void test_std_string_view()
122 {
123 std::string_view s = "hello";
124 const auto& cs = s;
125 using Q = decltype(std::quoted(s));
126 using CQ = decltype(std::quoted(cs));
127 static_assert( HasLeftShift<std::ostream&, Q>::value, "");
128 static_assert(!HasRightShift<std::istream&, Q>::value, "");
129 static_assert( HasLeftShift<std::ostream&, CQ>::value, "");
130 static_assert(!HasRightShift<std::istream&, CQ>::value, "");
131 static_assert(!HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, Q>::value, "");
132 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, Q>::value, "");
133 static_assert(!HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, CQ>::value, "");
134 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, CQ>::value, "");
135
136 std::basic_string_view<char, FakeCharTraits<char>> st = "hello";
137 const auto& cst = st;
138 using QT = decltype(std::quoted(st));
139 using CQT = decltype(std::quoted(cst));
140 static_assert(!HasLeftShift<std::ostream&, QT>::value, "");
141 static_assert(!HasRightShift<std::istream&, QT>::value, "");
142 static_assert(!HasLeftShift<std::ostream&, CQT>::value, "");
143 static_assert(!HasRightShift<std::istream&, CQT>::value, "");
144 static_assert( HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, QT>::value, "");
145 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, QT>::value, "");
146 static_assert( HasLeftShift<std::basic_ostream<char, FakeCharTraits<char>>&, CQT>::value, "");
147 static_assert(!HasRightShift<std::basic_istream<char, FakeCharTraits<char>>&, CQT>::value, "");
148
149 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
150 std::wstring_view ws = L"hello";
151 const auto& cws = ws;
152 using WQ = decltype(std::quoted(ws));
153 using CWQ = decltype(std::quoted(cws));
154 static_assert( HasLeftShift<std::wostream&, WQ>::value, "");
155 static_assert(!HasRightShift<std::wistream&, WQ>::value, "");
156 static_assert( HasLeftShift<std::wostream&, CWQ>::value, "");
157 static_assert(!HasRightShift<std::wistream&, CWQ>::value, "");
158 static_assert(!HasLeftShift<std::basic_ostream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
159 static_assert(!HasRightShift<std::basic_istream<wchar_t, FakeCharTraits<wchar_t>>&, WQ>::value, "");
160 static_assert(!HasLeftShift<std::basic_ostream<wchar_t, FakeCharTraits<wchar_t>>&, CWQ>::value, "");
161 static_assert(!HasRightShift<std::basic_istream<wchar_t, FakeCharTraits<wchar_t>>&, CWQ>::value, "");
162
163 static_assert(!HasLeftShift<std::ostream&, WQ>::value, "");
164 static_assert(!HasLeftShift<std::wostream&, Q>::value, "");
165 #endif // TEST_HAS_NO_WIDE_CHARACTERS
166 }
167