Merge remote-tracking branch 'origin/main' into updated-jungfrau-rotation-devices

Author: olliesilvester

src/dodal/testing/fixtures/run_engine.py

@@ -3,6 +3,7 @@
 """
 
 import asyncio
+import copy
 import os
 import threading
 import time
@@ -34,10 +35,13 @@ async def _ensure_running_bluesky_event_loop(_global_run_engine):
 
 @pytest.fixture()
 async def run_engine(_global_run_engine: RunEngine) -> AsyncGenerator[RunEngine, None]:
+    initial_md = copy.deepcopy(_global_run_engine.md)
     try:
         yield _global_run_engine
     finally:
+        # Clear subscriptions, cache, and reset metadata
         _global_run_engine.reset()
+        _global_run_engine.md = initial_md
 
 
 @pytest_asyncio.fixture(scope="session", loop_scope="session")

tests/testing/fixtures/test_run_engine.py

@@ -31,3 +31,14 @@ def test_run_engine_fixture_has_no_file_handler_leak(
                 f"{_baseline_n_open_files} to {n_open_files} when calling the "
                 "run_engine fixture",
             ) from exc
+
+
+def test_add_run_engine_metadata(run_engine: RunEngine):
+    run_engine.md["new_metadata"] = "test"
+
+
+# This will fail when tests are running in parallel if the RE's md hasn't been
+# correctly cleared
+def test_check_run_engine_metadata(run_engine: RunEngine):
+    with pytest.raises(KeyError):
+        run_engine.md["new_metadata"]