Always keep the current recorder run when purging (#43733)

homeassistant/components/recorder/purge.py

@@ -68,6 +68,7 @@ def purge_old_data(instance, purge_days: int, repack: bool) -> bool:
             deleted_rows = (
                 session.query(RecorderRuns)
                 .filter(RecorderRuns.start < purge_before)
+                .filter(RecorderRuns.run_id != instance.run_info.run_id)
                 .delete(synchronize_session=False)
             )
             _LOGGER.debug("Deleted %s recorder_runs", deleted_rows)

tests/components/recorder/test_purge.py

@@ -62,6 +62,22 @@ def test_purge_old_events(hass, hass_recorder):
         assert events.count() == 2
 
 
+def test_purge_old_recorder_runs(hass, hass_recorder):
+    """Test deleting old recorder runs keeps current run."""
+    hass = hass_recorder()
+    _add_test_recorder_runs(hass)
+
+    # make sure we start with 7 recorder runs
+    with session_scope(hass=hass) as session:
+        recorder_runs = session.query(RecorderRuns)
+        assert recorder_runs.count() == 7
+
+        # run purge_old_data()
+        finished = purge_old_data(hass.data[DATA_INSTANCE], 0, repack=False)
+        assert finished
+        assert recorder_runs.count() == 1
+
+
 def test_purge_method(hass, hass_recorder):
     """Test purge method."""
     hass = hass_recorder()