class RSpec::Core::Source::Node

def self.sexp?(array)
  array.is_a?(Array) && array.first.is_a?(Symbol)
end

def args
  @args ||= raw_args.map do |raw_arg|
    if Node.sexp?(raw_arg)
      Node.new(raw_arg, self)
    elsif Location.location?(raw_arg)
      Location.new(*raw_arg)
    elsif raw_arg.is_a?(Array)
      GroupNode.new(raw_arg, self)
    else
      raw_arg
    end
  end.freeze
end

def children
  @children ||= args.select { |arg| arg.is_a?(Node) }.freeze
end

def each(&block)
  return to_enum(__method__) unless block_given?
  yield self
  children.each do |child|
    child.each(&block)
  end
end

def each_ancestor
  return to_enum(__method__) unless block_given?
  current_node = self
  while (current_node = current_node.parent)
    yield current_node
  end
end

def initialize(ripper_sexp, parent=nil)
  @sexp = ripper_sexp.freeze
  @parent = parent
end

def inspect
  "#<#{self.class} #{type}>"
end

def location
  @location ||= args.find { |arg| arg.is_a?(Location) }
end

def raw_args
  sexp[1..-1] || []
end

def type
  sexp[0]
end