code: def test_list_artifacts_root(hdfs_system_mock):
      repo = HdfsArtifactRepository("hdfs://host/some/path")
  
      expected = [FileInfo("model", True, 0)]
  
      hdfs_system_mock.return_value.ls.return_value = [
          {
              "kind": "directory",
              "name": "hdfs://host/some/path/model",
              "size": 0,
          }
      ]
  
      actual = repo.list_artifacts()
  
      assert actual == expected
  
imports: import os
  import sys
  from io import BufferedReader
  from tempfile import NamedTemporaryFile
  from unittest import mock
  from unittest.mock import ANY, call, mock_open
  import pytest
  from pyarrow import HadoopFileSystem
  from mlflow.entities import FileInfo
  from mlflow.store.artifact.hdfs_artifact_repo import HdfsArtifactRepository, _download_hdfs_file, _parse_extra_conf, _relative_path_remote, _resolve_base_path
  from mlflow.utils.file_utils import TempDir
label_desc: Use image node_id 6 for calling a global function with example usage: test_list_artifacts_root(hdfs_system_mock) without return types