class RuboCop::Cop::Performance::SelectMap


ary.filter_map { |o| o.bar if o.foo }
# good
ary.filter(&:foo).map(&:bar)
ary.select(&:foo).map(&:bar)
# bad
@example
This cop identifies places where ‘select.map` can be replaced by `filter_map`.
In Ruby 2.7, `Enumerable#filter_map` has been added.

def map_method_candidate(node) 

def map_method_candidate(node)
  return unless (parent = node.parent)
  if parent.block_type? && parent.parent&.call_type?
    parent.parent
  elsif parent.call_type?
    parent
  end
end

def offense_range(node, map_method) 

def offense_range(node, map_method)
  range_between(node.loc.selector.begin_pos, map_method.source_range.end_pos)
end

def on_send(node) 

def on_send(node)
  return if (first_argument = node.first_argument) && !first_argument.block_pass_type?
  return unless (send_node = map_method_candidate(node))
  return unless send_node.method?(:map)
  map_method = send_node.parent&.block_type? ? send_node.parent : send_node
  range = offense_range(node, map_method)
  add_offense(range, message: format(MSG, method_name: node.method_name))
end