class Rubocop::Cop::Style::DotPosition

This cop checks the . position in multi-line method calls.

def on_send(node) 

def on_send(node)
  return unless node.loc.dot
  unless proper_dot_position?(node)
    add_offence(:convention, node.loc.dot, MSG)
  end
  super
end

def proper_dot_position?(node) 

def proper_dot_position?(node)
  dot_line = node.loc.dot.line
  selector_line = node.loc.selector.line
  case DotPosition.config['Style'].downcase
  when 'leading' then dot_line == selector_line
  when 'trailing' then dot_line != selector_line
  else fail 'Unknown dot position style selected.'
  end
end