class RuboCop::Cop::Layout::SpaceInsideReferenceBrackets

def closing_bracket(tokens, opening_bracket)
  i = tokens.index(opening_bracket)
  inner_left_brackets_needing_closure = 0
  tokens[i..-1].each do |token|
    inner_left_brackets_needing_closure += 1 if token.left_bracket?
    inner_left_brackets_needing_closure -= 1 if token.right_bracket?
    if inner_left_brackets_needing_closure.zero? && token.right_bracket?
      return token
    end
  end
end