synchronous_get: return -> raise exception

gui/qt/main_window.py

@@ -2272,13 +2272,13 @@ class ElectrumWindow(QMainWindow):
         from electrum import transaction
         txid, ok = QInputDialog.getText(self, _('Lookup transaction'), _('Transaction ID') + ':')
         if ok and txid:
+            try:
                 r = self.network.synchronous_get([('blockchain.transaction.get',[str(txid)])])[0]
-            if r:
+            except BaseException as e:
+                self.show_message(str(e))
+                return
             tx = transaction.Transaction(r)
-                if tx:
             self.show_transaction(tx)
-                else:
-                    self.show_message("unknown transaction")
 
 
     @protected

lib/network_proxy.py

@@ -170,7 +170,7 @@ class NetworkProxy(util.DaemonThread):
             _id = r.get('id')
             ids.remove(_id)
             if r.get('error'):
-                return BaseException(r.get('error'))
+                raise BaseException(r.get('error'))
             result = r.get('result')
             res[_id] = r.get('result')
         out = []