class RuboCop::Cop::Style::NestedParenthesizedCalls

method1(method2 arg, method3, arg)
@bad
method1(method2(arg), method3(arg))
@good
@example
of a parenthesized method call.
This cop checks for unparenthesized method calls in the argument list

def autocorrect(nested) 

def autocorrect(nested)
  _scope, _method_name, *args = *nested
  first_arg = args.first.source_range
  last_arg = args.last.source_range
  first_arg_with_space = range_with_surrounding_space(first_arg, :left)
  leading_space = first_arg_with_space.begin.resize(1)
  lambda do |corrector|
    corrector.replace(leading_space, '(')
    corrector.insert_after(last_arg, ')')
  end
end

def on_send(node) 

def on_send(node)
  return unless parenthesized_call?(node)
  node.each_child_node(:send) do |nested|
    next if nested.method_args.empty? ||
            parenthesized_call?(nested) ||
            operator?(nested.method_name) ||
            rspec_matcher?(node, nested) ||
            nested.asgn_method_call?
    add_offense(nested, nested.source_range, format(MSG, nested.source))
  end
end

def rspec_matcher?(parent, send) 

def rspec_matcher?(parent, send)
  parent.method_args.one? && # .to, .not_to, etc
    RSPEC_MATCHERS.include?(send.method_name) &&
    send.method_args.one?
end