code: def test_copier_handles_exception(stat_mock, dir_mock, monkeypatch):
      """Test that the Copier captures exceptions from the file copy and forwards them through the queue without raising
      it."""
      stat_mock().st_size = 0
      dir_mock.return_value = False
      copy_request_queue = _MockQueue()
      copy_response_queue = _MockQueue()
      fs = mock.Mock()
      fs.exists.return_value = False
      fs.put = mock.Mock(side_effect=OSError("Something went wrong"))
      monkeypatch.setattr(
          lightning.app.storage.copier,
          "_filesystem",
          mock.Mock(return_value=fs),
      )
  
      work = mock.Mock()
      work.name = MockPatch()
      work._paths = {
          "file": {
              "source": "src",
              "path": "file",
              "hash": "123",
              "destination": "dest",
              "name": "name",
          }
      }
      copier = _Copier(
          work,
          copy_request_queue=copy_request_queue,
          copy_response_queue=copy_response_queue,
      )
      request = _GetRequest(
          source="src",
          path="file",
          hash="123",
          destination="dest",
          name="name",
      )
      copy_request_queue.put(request)
      copier.run_once()
      response = copy_response_queue.get()
      assert type(response.exception) is OSError
      assert response.exception.args[0] == "Something went wrong"
  
file_path: pytorch-lightning/tests/tests_app/storage/test_copier.py
imports: import os
  import pathlib
  from unittest import mock
  from unittest.mock import Mock
  import lightning.app
  import pytest
  from lightning.app.storage.copier import _Copier, _copy_files
  from lightning.app.storage.path import Path
  from lightning.app.storage.requests import _ExistsRequest, _GetRequest
  from lightning.app.testing.helpers import _MockQueue
label_desc: Use image node_id 2 for calling a global function with example usage: test_copier_handles_exception(stat_mock, dir_mock, monkeypatch) without return types