class Protobuf::Visitor::CreateMessageVisitor

def required_message_from_proto(proto_file)
  rb_path = [
    proto_file.sub(/\.proto\z/, '.pb.rb')
  ].join('/').gsub(/\/{2,}/, '/')
  
  unless File.exist?(rb_path)
    Compiler.compile(proto_file, @proto_dir, @out_dir)
  end
  
  rb_path.sub(/\.rb$/, '')
end