fix race condition between downloading last file and starting install

tests/app/services/download/test_download_queue.py

@@ -166,6 +166,7 @@ def test_broken_callbacks(tmp_path: Path, session: Session, capsys) -> None:
     # assert re.search("division by zero", captured.err)
     queue.stop()
 
+
 @pytest.mark.timeout(timeout=15, method="thread")
 def test_cancel(tmp_path: Path, session: Session) -> None:
     event_bus = TestEventService()

tests/app/services/model_install/test_model_install.py

@@ -220,6 +220,7 @@ def test_simple_download(mm2_installer: ModelInstallServiceBase, mm2_app_config:
     event_names = [x.event_name for x in bus.events]
     assert event_names == ["model_install_downloading", "model_install_running", "model_install_completed"]
 
+
 @pytest.mark.timeout(timeout=20, method="thread")
 def test_huggingface_download(mm2_installer: ModelInstallServiceBase, mm2_app_config: InvokeAIAppConfig) -> None:
     source = URLModelSource(url=Url("https://huggingface.co/stabilityai/sdxl-turbo"))

tests/backend/model_manager/model_manager_fixtures.py

@@ -2,6 +2,7 @@
 
 import os
 import shutil
+import time
 from pathlib import Path
 from typing import Any, Dict, List
 
@@ -149,6 +150,7 @@ def mm2_installer(
 
     def stop_installer() -> None:
         installer.stop()
+        time.sleep(0.1)  # avoid error message from the logger when it is closed before thread prints final message
 
     request.addfinalizer(stop_installer)
     return installer