module RuboCop::Ext::RegexpParser::Expression::Base

def build_location
  return { body: expression } unless (q = quantifier)
  body = expression.adjust(end_pos: -q.text.length)
  q_loc = expression.with(begin_pos: body.end_pos)
  { body: body, quantifier: q_loc }
end

def expression
  @expression ||= origin.adjust(begin_pos: ts, end_pos: ts + full_length)
end

def expression
  end_pos = start_index + full_length
  @expression ||= origin.adjust(begin_pos: start_index, end_pos: end_pos)
end

def loc
  @loc ||= Map.new(expression, **build_location)
end

def start_index
  # ts is a byte index; convert it to a character index
  @start_index ||= source.byteslice(0, ts).length
end