function rangeToPattern(start, stop, options) {
  if (start === stop) {
    return {
      pattern: start,
      count: [],
      digits: 0
    };
  }

  let zipped = zip(start, stop);
  let digits = zipped.length;
  let pattern = '';
  let count = 0;

  for (let i = 0; i < digits; i++) {
    let [startDigit, stopDigit] = zipped[i];

    if (startDigit === stopDigit) {
      pattern += startDigit;
    } else if (startDigit !== '0' || stopDigit !== '9') {
      pattern += toCharacterClass(startDigit, stopDigit);
    } else {
      count++;
    }
  }

  if (count) {
    pattern += options.shorthand === true ? '\\d' : '[0-9]';
  }

  return {
    pattern,
    count: [count],
    digits
  };
}
Convert a range to a regex pattern
@param {Number} `start`
@param {Number} `stop`
@return {String}