libcxx/test/std/utilities/format/format.functions/vformat_to.locale.pass.cpp

   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
  10 // UNSUPPORTED: no-localization
  11 // UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME
  12
  13 // XFAIL: availability-fp_to_chars-missing
  14
  15 // <format>
  16
  17 // template<class Out>
  18 //   Out vformat_to(Out out, const locale& loc, string_view fmt,
  19 //                  format_args args);
  20 // template<class Out>
  21 //    Out vformat_to(Out out, const locale& loc, wstring_view fmt,
  22 //                   wformat_args args);
  23
  24 #include <format>
  25 #include <algorithm>
  26 #include <cassert>
  27 #include <list>
  28 #include <vector>
  29
  30 #include "assert_macros.h"
  31 #include "concat_macros.h"
  32 #include "format_tests.h"
  33 #include "string_literal.h"
  34
  35 auto test = []<class CharT, class... Args>(
  36                 std::basic_string_view<CharT> expected, std::basic_string_view<CharT> fmt, Args&&... args) constexpr {
  37   {
  38     std::basic_string<CharT> out(expected.size(), CharT(' '));
  39     auto it = std::vformat_to(out.begin(), std::locale(), fmt, std::make_format_args<context_t<CharT>>(args...));
  40     assert(it == out.end());
  41     assert(out == expected);
  42   }
  43   {
  44     std::list<CharT> out;
  45     std::vformat_to(std::back_inserter(out), std::locale(), fmt, std::make_format_args<context_t<CharT>>(args...));
  46     assert(std::equal(out.begin(), out.end(), expected.begin(), expected.end()));
  47   }
  48   {
  49     std::vector<CharT> out;
  50     std::vformat_to(std::back_inserter(out), std::locale(), fmt, std::make_format_args<context_t<CharT>>(args...));
  51     assert(std::equal(out.begin(), out.end(), expected.begin(), expected.end()));
  52   }
  53   {
  54     assert(expected.size() < 4096 && "Update the size of the buffer.");
  55     CharT out[4096];
  56     CharT* it = std::vformat_to(out, std::locale(), fmt, std::make_format_args<context_t<CharT>>(args...));
  57     assert(std::distance(out, it) == int(expected.size()));
  58     // Convert to std::string since output contains '\0' for boolean tests.
  59     assert(std::basic_string<CharT>(out, it) == expected);
  60   }
  61 };
  62
  63 auto test_exception = []<class CharT, class... Args>([[maybe_unused]] std::string_view what,
  64                                                      [[maybe_unused]] std::basic_string_view<CharT> fmt,
  65                                                      [[maybe_unused]] Args&&... args) {
  66   TEST_VALIDATE_EXCEPTION(
  67       std::format_error,
  68       [&]([[maybe_unused]] const std::format_error& e) {
  69         TEST_LIBCPP_REQUIRE(
  70             e.what() == what,
  71             TEST_WRITE_CONCATENATED(
  72                 "\nFormat string   ", fmt, "\nExpected exception ", what, "\nActual exception   ", e.what(), '\n'));
  73       },
  74       [&] {
  75         std::basic_string<CharT> out;
  76         std::vformat_to(std::back_inserter(out), std::locale(), fmt, std::make_format_args<context_t<CharT>>(args...));
  77       }());
  78 };
  79
  80 int main(int, char**) {
  81   format_tests<char, execution_modus::partial>(test, test_exception);
  82
  83 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  84   format_tests_char_to_wchar_t(test);
  85   format_tests<wchar_t, execution_modus::partial>(test, test_exception);
  86 #endif
  87
  88   return 0;
  89 }