class RuboCop::Cop::Lint::DuplicateCaseCondition

def on_case(case_node)
  case_node.when_branches.each_with_object([]) do |when_node, previous|
    when_node.each_condition do |condition|
      next unless repeated_condition?(previous, condition)
      add_offense(condition)
    end
    previous.push(when_node.conditions)
  end
end