class RuboCop::Cop::Style::Alias

def autocorrect(node)
  @corrections << lambda do |corrector|
    # replace alias with alias_method
    corrector.replace(node.loc.keyword, 'alias_method')
    # insert a comma
    new, old = *node
    corrector.insert_after(new.loc.expression, ',')
    # convert bareword arguments to symbols
    corrector.replace(new.loc.expression, ":#{new.children.first}")
    corrector.replace(old.loc.expression, ":#{old.children.first}")
  end
end

def on_alias(node)
  return if ignored_node?(node)
  # alias_method can't be used with global variables
  new, old = *node
  return if new.type == :gvar && old.type == :gvar
  add_offense(node, :keyword)
end

def on_block(node)
  method, _args, body = *node
  _receiver, method_name = *method
  # using alias is the only option in certain scenarios
  # in such scenarios we don't want to report an offense
  return unless method_name == :instance_exec
  body.each_node(:alias) { |n| ignore_node(n) }
end