class RuboCop::Cop::Lint::AmbiguousRegexpLiteral

def find_offense_node(node, regexp_receiver)
  return node if first_argument_is_regexp?(node) || !node.parent
  if (node.parent.send_type? && node.receiver) ||
     method_chain_to_regexp_receiver?(node, regexp_receiver)
    node = find_offense_node(node.parent, regexp_receiver)
  end
  node
end