fix access to Process, create mock objects explicitly

Author: andrii-i

jupyter_scheduler/tests/test_job_files_manager.py

@@ -4,7 +4,7 @@
 import tarfile
 import time
 from pathlib import Path
-from unittest.mock import patch
+from unittest.mock import patch, MagicMock
 
 import pytest
 
@@ -40,13 +40,20 @@ async def test_copy_from_staging():
         "input": "helloworld.ipynb",
     }
     output_dir = "jobs/1"
+
+    mock_scheduler = MagicMock()
+    mock_scheduler.get_job.return_value = job
+    mock_scheduler.get_staging_paths.return_value = staging_paths
+    mock_scheduler.get_local_output_path.return_value = output_dir
+    mock_scheduler.get_job_filenames.return_value = job_filenames
+
+    mock_context = MagicMock()
+    mock_process = MagicMock()
+    mock_context.Process.return_value = mock_process
+
     with patch("jupyter_scheduler.job_files_manager.Downloader") as mock_downloader:
-        with patch("jupyter_scheduler.job_files_manager.Process") as mock_process:
-            with patch("jupyter_scheduler.scheduler.Scheduler") as mock_scheduler:
-                mock_scheduler.get_job.return_value = job
-                mock_scheduler.get_staging_paths.return_value = staging_paths
-                mock_scheduler.get_local_output_path.return_value = output_dir
-                mock_scheduler.get_job_filenames.return_value = job_filenames
+        with patch("jupyter_scheduler.scheduler.Scheduler", return_value=mock_scheduler):
+            with patch("multiprocessing.get_context", return_value=mock_context):
                 manager = JobFilesManager(scheduler=mock_scheduler)
                 await manager.copy_from_staging(1)
 
@@ -58,6 +65,7 @@ async def test_copy_from_staging():
                     redownload=False,
                     include_staging_files=None,
                 )
+                mock_process.start.assert_called_once()
 
 
 HERE = Path(__file__).parent.resolve()