def evaluate_file(instance, filepath)
      absolute_path = File.expand_path(filepath)
      file_contents = IO.read(absolute_path)
      evaluate(instance, file_contents, absolute_path, 1)
    end
def evaluate_file(instance, filepath)
      absolute_path = File.expand_path(filepath)
      file_contents = IO.read(absolute_path)
      evaluate(instance, file_contents, absolute_path, 1)
    end
Evaluate the file in the context of the cleanroom.

 @param [Class] instance
   the instance of the class to evaluate against
 @param [String] filepath
   the path of the file to evaluate