Function generate_random_utf8_string

cpp/fory/util/string_util_test.cc:241–274

Generate random UTF-8 string

// Generate random UTF-8 string
std::string generate_random_utf8_string(size_t length) {
  std::string str;
  std::mt19937 generator(std::random_device{}());
  std::uniform_int_distribution<uint32_t> distribution(0, 0x10FFFF);

  while (str.size() < length) {
    uint32_t code_point = distribution(generator);

    // skip surrogate pairs (0xD800 to 0xDFFF) and other invalid Unicode code
    // points
    if ((code_point >= 0xD800 && code_point <= 0xDFFF) ||
        code_point > 0x10FFFF) {
      continue;
    }

    if (code_point <= 0x7F) {
      str.push_back(static_cast<char>(code_point));
    } else if (code_point <= 0x7FF) {
      str.push_back(0xC0 | (code_point >> 6));
      str.push_back(0x80 | (code_point & 0x3F));
    } else if (code_point <= 0xFFFF) {
      str.push_back(0xE0 | (code_point >> 12));
      str.push_back(0x80 | ((code_point >> 6) & 0x3F));
      str.push_back(0x80 | (code_point & 0x3F));
    } else {
      str.push_back(0xF0 | (code_point >> 18));
      str.push_back(0x80 | ((code_point >> 12) & 0x3F));
      str.push_back(0x80 | ((code_point >> 6) & 0x3F));
      str.push_back(0x80 | (code_point & 0x3F));
    }
  }

  return str;
}

// Testing Basic Logic
TEST(UTF8ToUTF16Test, BasicConversion) {