1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef SUPPORT_TEST_FORMAT_CONTEXT_HPP
11 #define SUPPORT_TEST_FORMAT_CONTEXT_HPP
12 
13 /**
14  * @file Helper functions to create a @ref std::basic_format_context.
15  *
16  * Since the standard doesn't specify how a @ref std::basic_format_context is
17  * constructed this is implementation defined. To make the public API tests of
18  * the class generic this header defines helper functions to create the
19  * required object.
20  *
21  * @note This requires every standard library implementation to write their own
22  * helper function. Vendors are encouraged to file a review at
23  * https://reviews.llvm.org/ so their specific implementation can be part of
24  * this file.
25  */
26 
27 #if TEST_STD_VER < 20
28 #error "The format header requires at least C++20"
29 #endif
30 
31 #include <format>
32 
33 #ifndef _LIBCPP_HAS_NO_LOCALIZATION
34 #include <locale>
35 #endif
36 
37 #if defined(_LIBCPP_VERSION)
38 
39 /** Creates a std::basic_format_context as-if the formatting function takes no locale. */
40 template <class OutIt, class CharT>
41 std::basic_format_context<OutIt, CharT> test_format_context_create(
42     OutIt out_it,
43     std::basic_format_args<std::basic_format_context<OutIt, CharT>> args) {
44   return std::__format_context_create(std::move(out_it), args);
45 }
46 
47 #ifndef _LIBCPP_HAS_NO_LOCALIZATION
48 /** Creates a std::basic_format_context as-if the formatting function takes locale. */
49 template <class OutIt, class CharT>
50 std::basic_format_context<OutIt, CharT> test_format_context_create(
51     OutIt out_it,
52     std::basic_format_args<std::basic_format_context<OutIt, CharT>> args,
53     std::locale loc) {
54   return std::__format_context_create(std::move(out_it), args, std::move(loc));
55 }
56 #endif
57 #else
58 #error                                                                         \
59     "Please create a vendor specific version of the test functions and file a review at https://reviews.llvm.org/"
60 #endif
61 
62 #endif // SUPPORT_TEST_FORMAT_CONTEXT_HPP
63