def test_file_output(self):
        output_dir = os.path.join(os.getcwd(), ".test")

        try:
            shutil.rmtree(output_dir)
        except:
            pass

        X_train, Y_train, X_test, Y_test = get_dataset('iris')
        X_valid = X_test[:25, ]
        Y_valid = Y_test[:25, ]
        X_test = X_test[25:, ]
        Y_test = Y_test[25:, ]

        D = Dummy()
        D.info = {'metric': 'bac_metric', 'task': MULTICLASS_CLASSIFICATION,
                  'is_sparse': False, 'target_num': 3}
        D.data = {'X_train': X_train, 'Y_train': Y_train,
                  'X_valid': X_valid, 'X_test': X_test}
        D.feat_type = ['numerical', 'Numerical', 'numerical', 'numerical']
        D.basename = "test"


        configuration_space = get_configuration_space(D.info)

        while True:
            configuration = configuration_space.sample_configuration()
            evaluator = HoldoutEvaluator(D, configuration,
                                         with_predictions=True,
                                         all_scoring_functions=True,
                                         output_dir=output_dir,
                                         output_y_test=True)

            if not self._fit(evaluator):
                print
                continue
            evaluator.predict()
            evaluator.file_output()

            self.assertTrue(os.path.exists(os.path.join(output_dir,
                                                        "y_optimization.npy")))
            break