libcxx/test/std/utilities/format/format.range/format.range.fmtdef/parse.pass.cpp

   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, c++20
   9
  10 // UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME
  11
  12 // <format>
  13
  14 // template<ranges::input_range R, class charT>
  15 //   struct range-default-formatter<range_format::sequence, R, charT>
  16
  17 // template<class ParseContext>
  18 //   constexpr typename ParseContext::iterator
  19 //     parse(ParseContext& ctx);
  20
  21 #include <array>
  22 #include <cassert>
  23 #include <concepts>
  24 #include <format>
  25
  26 #include "test_format_context.h"
  27 #include "test_macros.h"
  28 #include "make_string.h"
  29
  30 #define SV(S) MAKE_STRING_VIEW(CharT, S)
  31
  32 template <class StringViewT>
  33 constexpr void test_parse(StringViewT fmt, std::size_t offset) {
  34   using CharT    = typename StringViewT::value_type;
  35   auto parse_ctx = std::basic_format_parse_context<CharT>(fmt);
  36   std::formatter<std::array<int, 2>, CharT> formatter;
  37   static_assert(std::semiregular<decltype(formatter)>);
  38
  39   std::same_as<typename StringViewT::iterator> auto it = formatter.parse(parse_ctx);
  40   assert(it == fmt.end() - offset);
  41 }
  42
  43 template <class CharT>
  44 constexpr void test_fmt() {
  45   test_parse(SV(""), 0);
  46   test_parse(SV(":5"), 0);
  47
  48   test_parse(SV("}"), 1);
  49   test_parse(SV(":5}"), 1);
  50 }
  51
  52 constexpr bool test() {
  53   test_fmt<char>();
  54 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  55   test_fmt<wchar_t>();
  56 #endif
  57
  58   return true;
  59 }
  60
  61 int main(int, char**) {
  62   test();
  63   static_assert(test());
  64
  65   return 0;
  66 }