xref: /llvm-project/libcxx/test/std/utilities/format/format.functions/format.pass.cpp (revision aed5ddf8d09762f3adb80dc842239ad67ed2e301)
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 // TODO FMT Evaluate gcc-11 status
11 // UNSUPPORTED: gcc-11
12 // TODO FMT Investigate AppleClang ICE
13 // UNSUPPORTED: apple-clang-13
14 
15 // Note this formatter shows additional information when tests are failing.
16 // This aids the development. Since other formatters fail in the same fashion
17 // they don't have this additional output.
18 
19 // <format>
20 
21 // template<class... Args>
22 //   string format(format-string<Args...> fmt, const Args&... args);
23 // template<class... Args>
24 //   wstring format(wformat-string<Args...> fmt, const Args&... args);
25 
26 #include <format>
27 #include <cassert>
28 #include <vector>
29 
30 #include "test_macros.h"
31 #include "format_tests.h"
32 #include "string_literal.h"
33 
34 #ifndef TEST_HAS_NO_LOCALIZATION
35 #  include <iostream>
36 #  include <type_traits>
37 #endif
38 
39 auto test = []<string_literal fmt, class CharT, class... Args>(std::basic_string_view<CharT> expected,
40                                                                const Args&... args) constexpr {
41   std::basic_string<CharT> out = std::format(fmt.template sv<CharT>(), args...);
42 #ifndef TEST_HAS_NO_LOCALIZATION
43   if constexpr (std::same_as<CharT, char>)
44     if (out != expected)
45       std::cerr << "\nFormat string   " << fmt.template sv<char>() << "\nExpected output " << expected
46                 << "\nActual output   " << out << '\n';
47 #endif
48   assert(out == expected);
49 };
50 
51 auto test_exception = []<class CharT, class... Args>(std::string_view, std::basic_string_view<CharT>, const Args&...) {
52   // After P2216 most exceptions thrown by std::format become ill-formed.
53   // Therefore this tests does nothing.
54   // A basic ill-formed test is done in format.verify.cpp
55   // The exceptions are tested by other functions that don't use the basic-format-string as fmt argument.
56 };
57 
58 int main(int, char**) {
59   format_tests<char>(test, test_exception);
60 
61 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
62   format_tests_char_to_wchar_t(test);
63   format_tests<wchar_t>(test, test_exception);
64 #endif
65 
66   return 0;
67 }
68