Split Text Utils

function verifyString(
  data,
  error = Error,
  errorMessage = `Expected a string, got ${data} instead.`,
  allowEmpty = true,
) {
  if (typeof data !== 'string') throw new error(errorMessage);
  if (!allowEmpty && data.length === 0) throw new error(errorMessage);
  return data;
}

let deprecationEmittedForSplitMessage = false;
function splitMessage(text, { maxLength = 2_000, char = '\n', prepend = '', append = '' } = {}) {
  if (!deprecationEmittedForSplitMessage) {
    process.emitWarning(
      'The Util.splitMessage method is deprecated and will be removed in the next major version.',
      'DeprecationWarning',
    );

    deprecationEmittedForSplitMessage = true;
  }

  text = verifyString(text);
  if (text.length <= maxLength) return [text];
  let splitText = [text];
  if (Array.isArray(char)) {
    while (char.length > 0 && splitText.some((elem) => elem.length > maxLength)) {
      const currentChar = char.shift();
      if (currentChar instanceof RegExp) {
        splitText = splitText.flatMap((chunk) => chunk.match(currentChar));
      } else {
        splitText = splitText.flatMap((chunk) => chunk.split(currentChar));
      }
    }
  } else {
    splitText = text.split(char);
  }
  if (splitText.some((elem) => elem.length > maxLength)) throw new RangeError('SPLIT_MAX_LEN');
  const messages = [];
  let msg = '';
  for (const chunk of splitText) {
    if (msg && (msg + char + chunk + append).length > maxLength) {
      messages.push(msg + append);
      msg = prepend;
    }
    msg += (msg && msg !== prepend ? char : '') + chunk;
  }
  return messages.concat(msg).filter((m) => m);
}

js