class RuboCop::AST::Builder

root_node = parser.parse(buffer)
parser = Parser::Ruby25.new(builder)
require ‘parser/ruby25’
builder = RuboCop::AST::Builder.new
buffer.source = ‘puts :foo’
buffer = Parser::Source::Buffer.new(‘(string)’)
@example
generate ASTs with {RuboCop::AST::Node}.
‘RuboCop::AST::Builder` is an AST builder that is utilized to let `Parser`

def n(type, children, source_map)

Returns:
  • (Node) - the generated node 
def n(type, children, source_map)
  node_klass(type).new(type, children, location: source_map)
end

def node_klass(type) 

def node_klass(type)
  NODE_MAP[type] || Node
end

def string_value(token)

More details here https://github.com/whitequark/parser/issues/283
TODO: Figure out what to do about literal encoding handling... 
def string_value(token)
  value(token)
end