xref: /llvm-project/libcxx/test/std/utilities/format/format.functions/format_to.verify.cpp (revision 6a54dfbfe534276d644d7f9c027f0deeb748dd53)
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, c++17
10 
11 // TODO FMT This test should not require std::to_chars(floating-point)
12 // XFAIL: availability-fp_to_chars-missing
13 
14 // <format>
15 
16 // Basic test to validate ill-formed code is properly detected.
17 
18 // template<class Out, class... Args>
19 //   Out format_to(Out out, format-string<Args...> fmt, const Args&... args);
20 // template<class Out, class... Args>
21 //   Out format_to(Out out, wformat-string<Args...> fmt, const Args&... args);
22 
23 #include <format>
24 
25 #include "test_macros.h"
26 
27 extern char* out;
28 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
29 extern wchar_t* wout;
30 #endif
31 
32 // clang-format off
33 
34 void f() {
35   std::format_to(out, "{"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
36   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
37 
38   std::format_to(out, "}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
39   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
40 
41   std::format_to(out, "{}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
42   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
43 
44   std::format_to(out, "{0}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
45   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
46 
47   std::format_to(out, "{:-}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
48   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
49 
50   std::format_to(out, "{:#}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
51   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
52 
53   std::format_to(out, "{:L}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
54   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
55 
56   std::format_to(out, "{0:{0}}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
57   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
58 
59   std::format_to(out, "{:.42d}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
60   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
61 
62   std::format_to(out, "{:d}", "Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
63   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
64 
65 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
66   std::format_to(wout, L"{"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
67   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
68 
69   std::format_to(wout, L"}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
70   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
71 
72   std::format_to(wout, L"{}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
73   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
74 
75   std::format_to(wout, L"{0}"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
76   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
77 
78   std::format_to(wout, L"{:-}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
79   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
80 
81   std::format_to(wout, L"{:#}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
82   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
83 
84   std::format_to(wout, L"{:L}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
85   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
86 
87   std::format_to(wout, L"{0:{0}}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
88   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
89 
90   std::format_to(wout, L"{:.42d}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
91   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
92 
93   std::format_to(wout, L"{:d}", L"Forty-two"); // expected-error-re{{call to consteval function '{{.*}}' is not a constant expression}}
94   // expected-note@*:* {{non-constexpr function '__throw_format_error' cannot be used in a constant expression}}
95 #endif
96 }
97