code: function _getNextCommentIndex(comments, node) {
    return comments.findIndex((comment, index, array) => {
      if (index >= (array.length - 1)) {
        return Boolean(node.start >= comment.end);
      }
      const next = array[index + 1];
      return (node.start >= comment.end && node.end <= next.start);
    });
  }
docs: Private: determines the index for the comment in the `comments`
  
  * `comments` {Array} of AtomDoc comments.
  * `node` the current {Node}, this method uses the `start` property to find the
  location of the next comment and return its index.
  
  Returns {Integer} index of the next comment.