xref: /llvm-project/libcxx/test/support/test_format_string.h (revision 8cd5e672602676877b9025a750b20f895ca0bc25)
1d23f609dSMark de Wever // -*- C++ -*-
2d23f609dSMark de Wever //===----------------------------------------------------------------------===//
3d23f609dSMark de Wever //
4d23f609dSMark de Wever // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5d23f609dSMark de Wever // See https://llvm.org/LICENSE.txt for license information.
6d23f609dSMark de Wever // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7d23f609dSMark de Wever //
8d23f609dSMark de Wever //===----------------------------------------------------------------------===//
9d23f609dSMark de Wever 
10d23f609dSMark de Wever #ifndef SUPPORT_TEST_FORMAT_STRING_HPP
11d23f609dSMark de Wever #define SUPPORT_TEST_FORMAT_STRING_HPP
12d23f609dSMark de Wever 
13d23f609dSMark de Wever #include <concepts>
14d23f609dSMark de Wever #include <format>
15d23f609dSMark de Wever #include <type_traits>
16d23f609dSMark de Wever 
17d23f609dSMark de Wever #include "test_macros.h"
18d23f609dSMark de Wever 
19d23f609dSMark de Wever #if TEST_STD_VER < 20
20d23f609dSMark de Wever #  error "The format header requires at least C++20"
21d23f609dSMark de Wever #endif
22d23f609dSMark de Wever 
23d23f609dSMark de Wever // Wrapper for basic_format_string.
24d23f609dSMark de Wever //
25d23f609dSMark de Wever // This layer of indirection is used since it's not possible to use
26d23f609dSMark de Wever // std::basic_format_string<CharT, Args...> in the test function directly.
27d23f609dSMark de Wever //
28d23f609dSMark de Wever // In C++20 the basic-format-string was an exposition only type. In C++23 is
29d23f609dSMark de Wever // has been replaced with basic_format_string. Both libc++ and MSVC STL offer
30d23f609dSMark de Wever // it as an extension in C++20.
31d23f609dSMark de Wever #if TEST_STD_VER > 20 || defined(_LIBCPP_VERSION) || defined(_MSVC_STL_VERSION)
32d23f609dSMark de Wever #  ifndef TEST_HAS_NO_WIDE_CHARACTERS
33d23f609dSMark de Wever template <class CharT, class... Args>
34d23f609dSMark de Wever using test_format_string =
35d23f609dSMark de Wever     std::conditional_t<std::same_as<CharT, char>, std::format_string<Args...>, std::wformat_string<Args...>>;
36d23f609dSMark de Wever #  else
37d23f609dSMark de Wever template <class CharT, class... Args>
38d23f609dSMark de Wever using test_format_string = std::format_string<Args...>;
39d23f609dSMark de Wever #  endif
40d23f609dSMark de Wever 
41d23f609dSMark de Wever #else // TEST_STD_VER > 20 || defined(_LIBCPP_VERSION) || defined( _MSVC_STL_VERSION)
42d23f609dSMark de Wever 
43*8cd5e672SMark de Wever #  error                                                                                                               \
44*8cd5e672SMark de Wever       "Please create a vendor specific version of the test typedef and file a PR at https://github.com/llvm/llvm-project"
45d23f609dSMark de Wever 
46d23f609dSMark de Wever #endif // TEST_STD_VER > 20 || defined(_LIBCPP_VERSION) || defined( _MSVC_STL_VERSION)
47d23f609dSMark de Wever 
48d23f609dSMark de Wever #endif // SUPPORT_TEST_FORMAT_STRING_HPP
49