wallet.get_relevant_invoice_keys_for_tx: take lock in callee not caller

electrum/wallet.py

@@ -766,6 +766,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
 
     def _get_relevant_invoice_keys_for_tx(self, tx: Transaction) -> Set[str]:
         relevant_invoice_keys = set()
+        with self.transaction_lock:
             for txout in tx.outputs():
                 for invoice_key in self._invoices_from_scriptpubkey_map.get(txout.scriptpubkey, set()):
                     # note: the invoice might have been deleted since, so check now:
@@ -816,8 +817,8 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
         return self._is_onchain_invoice_paid(invoice)[0]
 
     def _maybe_set_tx_label_based_on_invoices(self, tx: Transaction) -> bool:
+        # note: this is not done in 'get_default_label' as that would require deserializing each tx
         tx_hash = tx.txid()
-        with self.transaction_lock:
         labels = []
         for invoice in self.get_relevant_invoices_for_tx(tx):
             if invoice.message: