class RuboCop::Cop::PunctuationCorrector

def add_space(token)
  ->(corrector) { corrector.replace(token.pos, token.pos.source + ' ') }
end

def remove_space(space_before)
  ->(corrector) { corrector.remove(space_before) }
end

def swap_comma(range)
  return unless range
  lambda do |corrector|
    case range.source
    when ',' then corrector.remove(range)
    else          corrector.insert_after(range, ',')
    end
  end
end