xref: /llvm-project/libcxx/test/std/utilities/format/format.functions/format.runtime_format.pass.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, c++20, c++23
10 // UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME
11 
12 // XFAIL: availability-fp_to_chars-missing
13 
14 // <format>
15 
16 // Tests the behavior of
17 //
18 // runtime-format-string<char> runtime_format(string_view fmt) noexcept;
19 // runtime-format-string<wchar_t> runtime_format(wstring_view fmt) noexcept;
20 //
21 // and
22 //
23 // template<class charT, class... Args>
24 //   struct basic_format_string {
25 //   ...
26 //   basic_format_string(runtime-format-string<charT> s) noexcept : str(s.str) {}
27 //   ...
28 // }
29 //
30 // This is done by testing it in the top-level functions:
31 //
32 // template<class... Args>
33 //   string format(format_string<Args...> fmt, Args&&... args);
34 // template<class... Args>
35 //   wstring format(wformat_string<Args...> fmt, Args&&... args);
36 //
37 // The basics of runtime_format and basic_format_string's constructor are tested in
38 // - libcxx/test/std/utilities/format/format.syn/runtime_format_string.pass.cpp
39 // - libcxx/test/std/utilities/format/format.fmt.string/ctor.runtime-format-string.pass.cpp
40 
41 #include <format>
42 #include <cassert>
43 #include <vector>
44 
45 #include "test_macros.h"
46 #include "format_tests.h"
47 #include "string_literal.h"
48 #include "assert_macros.h"
49 #include "concat_macros.h"
50 
51 auto test = []<class CharT, class... Args>(
52                 std::basic_string_view<CharT> expected, std::basic_string_view<CharT> fmt, Args&&... args) constexpr {
53   std::basic_string<CharT> out = std::format(std::runtime_format(fmt), std::forward<Args>(args)...);
54   TEST_REQUIRE(out == expected,
55                TEST_WRITE_CONCATENATED(
56                    "\nFormat string   ", fmt, "\nExpected output ", expected, "\nActual output   ", out, '\n'));
57 };
58 
59 auto test_exception =
60     []<class CharT, class... Args>(
61         [[maybe_unused]] std::string_view what,
62         [[maybe_unused]] std::basic_string_view<CharT> fmt,
63         [[maybe_unused]] Args&&... args) {
64       TEST_VALIDATE_EXCEPTION(
65           std::format_error,
66           [&]([[maybe_unused]] const std::format_error& e) {
67             TEST_LIBCPP_REQUIRE(
68                 e.what() == what,
69                 TEST_WRITE_CONCATENATED(
70                     "\nFormat string   ", fmt, "\nExpected exception ", what, "\nActual exception   ", e.what(), '\n'));
71           },
72           TEST_IGNORE_NODISCARD std::format(std::runtime_format(fmt), std::forward<Args>(args)...));
73     };
74 
75 int main(int, char**) {
76   format_tests<char, execution_modus::partial>(test, test_exception);
77 
78 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
79   format_tests_char_to_wchar_t(test);
80   format_tests<wchar_t, execution_modus::partial>(test, test_exception);
81 #endif
82 
83   return 0;
84 }
85