def METHOD_NAME(multi_file_repository):
    retrieved_file_names_1 = multi_file_repository.get_all_file_names()
    multi_file_repository.delete_files_by_regex(re.compile(r"f\d"))
    retrieved_file_names_2 = multi_file_repository.get_all_file_names()
    assert retrieved_file_names_2 != retrieved_file_names_1
    assert len(retrieved_file_names_2) == 0