fix: test-harness was breaking w 3.0 RC (closes #14483) (#14798)

src/prefect/testing/utilities.py

@@ -2,11 +2,13 @@
 Internal utilities for tests.
 """
 
+import atexit
+import shutil
 import warnings
 from contextlib import ExitStack, contextmanager
 from pathlib import Path
 from pprint import pprint
-from tempfile import TemporaryDirectory
+from tempfile import mkdtemp
 from typing import TYPE_CHECKING, Dict, List, Union
 
 import prefect.context
@@ -118,24 +120,30 @@ def prefect_test_harness():
     from prefect.server.database.dependencies import temporary_database_interface
 
     # create temp directory for the testing database
-    with TemporaryDirectory() as temp_dir:
-        with ExitStack() as stack:
-            # temporarily override any database interface components
-            stack.enter_context(temporary_database_interface())
-
-            DB_PATH = "sqlite+aiosqlite:///" + str(Path(temp_dir) / "prefect-test.db")
-            stack.enter_context(
-                prefect.settings.temporary_settings(
-                    # Clear the PREFECT_API_URL
-                    restore_defaults={prefect.settings.PREFECT_API_URL},
-                    # Use a temporary directory for the database
-                    updates={
-                        prefect.settings.PREFECT_API_DATABASE_CONNECTION_URL: DB_PATH,
-                        prefect.settings.PREFECT_API_URL: None,
-                    },
-                )
+    temp_dir = mkdtemp()
+
+    def cleanup_temp_dir(temp_dir):
+        shutil.rmtree(temp_dir)
+
+    atexit.register(cleanup_temp_dir, temp_dir)
+
+    with ExitStack() as stack:
+        # temporarily override any database interface components
+        stack.enter_context(temporary_database_interface())
+
+        DB_PATH = "sqlite+aiosqlite:///" + str(Path(temp_dir) / "prefect-test.db")
+        stack.enter_context(
+            prefect.settings.temporary_settings(
+                # Clear the PREFECT_API_URL
+                restore_defaults={prefect.settings.PREFECT_API_URL},
+                # Use a temporary directory for the database
+                updates={
+                    prefect.settings.PREFECT_API_DATABASE_CONNECTION_URL: DB_PATH,
+                    prefect.settings.PREFECT_API_URL: None,
+                },
             )
-            yield
+        )
+        yield
 
 
 async def get_most_recent_flow_run(client: "PrefectClient" = None):