llvm/libcxx/test/std/utilities/format/format.functions/vformat.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++03, c++11, c++14, c++17
// UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME

// XFAIL: availability-fp_to_chars-missing

// <format>

// string vformat(string_view fmt, format_args args);
// wstring vformat(wstring_view fmt, wformat_args args);

#include <format>
#include <cassert>
#include <vector>

#include "test_macros.h"
#include "format_tests.h"
#include "string_literal.h"
#include "assert_macros.h"
#include "concat_macros.h"

auto test = []<class CharT, class... Args>(
                std::basic_string_view<CharT> expected, std::basic_string_view<CharT> fmt, Args&&... args) constexpr {
  std::basic_string<CharT> out = std::vformat(fmt, std::make_format_args<context_t<CharT>>(args...));
  TEST_REQUIRE(out == expected,
               TEST_WRITE_CONCATENATED(
                   "\nFormat string   ", fmt, "\nExpected output ", expected, "\nActual output   ", out, '\n'));
};

auto test_exception =
    []<class CharT, class... Args>(
        [[maybe_unused]] std::string_view what,
        [[maybe_unused]] std::basic_string_view<CharT> fmt,
        [[maybe_unused]] Args&&... args) {
      TEST_VALIDATE_EXCEPTION(
          std::format_error,
          [&]([[maybe_unused]] const std::format_error& e) {
            TEST_LIBCPP_REQUIRE(
                e.what() == what,
                TEST_WRITE_CONCATENATED(
                    "\nFormat string   ", fmt, "\nExpected exception ", what, "\nActual exception   ", e.what(), '\n'));
          },
          TEST_IGNORE_NODISCARD std::vformat(fmt, std::make_format_args<context_t<CharT>>(args...)));
    };

int main(int, char**) {
#if !defined(TEST_HAS_NO_EXCEPTIONS)
  // reproducer of https://llvm.org/PR65011
  try {
    const char fmt[] = {'{', '0'};
    char buf[4096];
    [[maybe_unused]] auto ignored =
        std::vformat_to(buf, std::string_view{fmt, fmt + sizeof(fmt)}, std::make_format_args());
  } catch (...) {
  }
#endif // !defined(TEST_HAS_NO_EXCEPTIONS)

  format_tests<char, execution_modus::full>(test, test_exception);

#ifndef TEST_HAS_NO_WIDE_CHARACTERS
  format_tests_char_to_wchar_t(test);
  format_tests<wchar_t, execution_modus::full>(test, test_exception);
#endif

  return 0;
}