broadcast: fix dictionary changed size during iteration error

* Closes #6222
cylc · Oct 9, 2024 · a689907 · a689907
1 parent 372e01e
commit a689907
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/cylc/flow/data_store_mgr.py b/cylc/flow/data_store_mgr.py
@@ -2251,7 +2251,9 @@ def delta_broadcast(self):
 
     def _generate_broadcast_node_deltas(self, node_data, node_type):
         cfg = self.schd.config.cfg
-        for node_id, node in node_data.items():
+        # NOTE: node_data may change during operation so make a copy
+        # see https://github.com/cylc/cylc-flow/pull/6397
+        for node_id, node in list(node_data.items()):
             tokens = Tokens(node_id)
             new_runtime = runtime_from_config(
                 self._apply_broadcasts_to_runtime(