class RuboCop::Cop::Style::LineEndConcatenation

def check_token_set(index)
  tokens = processed_source.tokens
  predecessor = tokens[index]
  operator = tokens[index + 1]
  successor = tokens[index + 2]
  return unless eligible_token_set?(predecessor, operator, successor)
  return if same_line?(operator, successor)
  next_successor = token_after_last_string(successor, index)
  return unless eligible_next_successor?(next_successor)
  add_offense(operator.pos) { |corrector| autocorrect(corrector, operator.pos) }
end