docstr: Directory to scan is a file raises ValueError.
docstr_tok: ["Directory","to","scan","is","a","file","raises","ValueError","."]
code: def test_cache_dir_is_a_file(self) -> None:
      """Directory to scan is a file raises ValueError."""
      file_path = self.cache_dir / "file.txt"
      file_path.touch()
      self.assertRaises(ValueError, scan_cache_dir, file_path)
  
imports: import os
  import tempfile
  import time
  import unittest
  from pathlib import Path
  from unittest.mock import Mock
  import pytest
  from huggingface_hub._snapshot_download import snapshot_download
  from huggingface_hub.commands.scan_cache import ScanCacheCommand
  from huggingface_hub.utils import DeleteCacheStrategy, HFCacheInfo, capture_output, scan_cache_dir
  from huggingface_hub.utils._cache_manager import CacheNotFound, _format_size, _format_timesince, _try_delete_path
  from .testing_constants import TOKEN
  from .testing_utils import rmtree_with_retry, with_production_testing, xfail_on_windows
label_desc: Use image node_id 2 for calling the TestMissingCacheUtils obj's underlying member method code with example usage: obj.test_cache_dir_is_a_file() without return types