llvm/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.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

// <string>

// template<> struct char_traits<char8_t>

// static constexpr size_t length(const char_type* s);

#include <string>
#include <cassert>

#include "test_macros.h"

#ifndef TEST_HAS_NO_CHAR8_T
constexpr bool test_constexpr() {
  return std::char_traits<char8_t>::length(u8"") == 0 && std::char_traits<char8_t>::length(u8"abcd") == 4;
}

int main(int, char**) {
  assert(std::char_traits<char8_t>::length(u8"") == 0);
  assert(std::char_traits<char8_t>::length(u8"a") == 1);
  assert(std::char_traits<char8_t>::length(u8"aa") == 2);
  assert(std::char_traits<char8_t>::length(u8"aaa") == 3);
  assert(std::char_traits<char8_t>::length(u8"aaaa") == 4);

  static_assert(test_constexpr(), "");
  return 0;
}
#else
int main(int, char**) { return 0; }
#endif