code: function skipNewline(text, index, opts) {
    const backwards = opts && opts.backwards;
    if (index === false) {
      return false;
    }
  
    const atIndex = text.charAt(index);
    if (backwards) {
      if (text.charAt(index - 1) === "\r" && atIndex === "\n") {
        return index - 2;
      }
      if (
        atIndex === "\n" ||
        atIndex === "\r" ||
        atIndex === "\u2028" ||
        atIndex === "\u2029"
      ) {
        return index - 1;
      }
    } else {
      if (atIndex === "\r" && text.charAt(index + 1) === "\n") {
        return index + 2;
      }
      if (
        atIndex === "\n" ||
        atIndex === "\r" ||
        atIndex === "\u2028" ||
        atIndex === "\u2029"
      ) {
        return index + 1;
      }
    }
  
    return index;
  }
docs: This one doesn't use the above helper function because it wants to test \r\n in order and `skip` doesn't support ordering and we only want to skip one newline. It's simple to implement.