xref: /llvm-project/libcxx/test/std/utilities/format/format.functions/format.verify.cpp (revision 56065c4c8e2933518eedf7722d031c9c22762c79)
1 //===----------------------------------------------------------------------===//
2 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
3 // See https://llvm.org/LICENSE.txt for license information.
4 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
5 //
6 //===----------------------------------------------------------------------===//
7 
8 // UNSUPPORTED: c++03, c++11, c++14, c++17
9 // UNSUPPORTED: libcpp-has-no-incomplete-format
10 
11 // Basic test to validate ill-formed code is properly detected.
12 
13 // <format>
14 
15 // template<class... Args>
16 //   string format(format-string<Args...> fmt, const Args&... args);
17 // template<class... Args>
18 //   wstring format(wformat-string<Args...> fmt, const Args&... args);
19 
20 #include <format>
21 
22 #include "test_macros.h"
23 
24 // clang-format off
25 
26 void f() {
27   std::format("{"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
28   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
29 
30   std::format("}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
31   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
32 
33   std::format("{}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
34   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
35 
36   std::format("{0}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
37   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
38 
39   std::format("{:-}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
40   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
41 
42   std::format("{:#}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
43   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
44 
45   std::format("{:L}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
46   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
47 
48   std::format("{0:{0}}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
49   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
50 
51   std::format("{:.42d}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
52   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
53 
54   std::format("{:d}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
55   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
56 
57 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
58   std::format(L"{"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
59   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
60 
61   std::format(L"}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
62   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
63 
64   std::format(L"{}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
65   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
66 
67   std::format(L"{0}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
68   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
69 
70   std::format(L"{:-}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
71   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
72 
73   std::format(L"{:#}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
74   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
75 
76   std::format(L"{:L}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
77   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
78 
79   std::format(L"{0:{0}}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
80   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
81 
82   std::format(L"{:.42d}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
83   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
84 
85   std::format(L"{:d}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
86   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
87 #endif
88 }
89 
90 struct tiny {
91   int bit : 1;
92 };
93 
94 void P2418()
95 {
96   auto t = tiny{};
97   std::format("{}", t.bit); // expected-error{{non-const reference cannot bind to bit-field 'bit'}}
98 
99 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
100   std::format(L"{}", t.bit); // expected-error{{non-const reference cannot bind to bit-field 'bit'}}
101 #endif
102 }
103