class RuboCop::Cop::Lint::ParenthesesAsGroupedExpression

def spaces_before_left_parenthesis(node)
  receiver = node.receiver
  receiver_length = if receiver
                      receiver.source.length
                    else
                      0
                    end
  without_receiver = node.source[receiver_length..]
  # Escape question mark if any.
  method_regexp = Regexp.escape(node.method_name)
  match = without_receiver.match(/^\s*&?\.?\s*#{method_regexp}(\s+)\(/)
  match ? match.captures[0].length : 0
end