Handle no matching symbols case

piker/brokers/ib.py

@@ -245,6 +245,7 @@ class Client:
         """
         descriptions = await self.ib.reqMatchingSymbolsAsync(pattern)
 
+        if descriptions is not None:
             futs = []
             for d in descriptions:
                 con = d.contract
@@ -267,6 +268,9 @@ class Client:
 
             return details
 
+        else:
+            return {}
+
     async def search_futes(
         self,
         pattern: str,
@@ -562,7 +566,7 @@ class Client:
 # default config ports
 _tws_port: int = 7497
 _gw_port: int = 4002
-_try_ports = [_tws_port, _gw_port]
+_try_ports = [_gw_port, _tws_port]
 _client_ids = itertools.count()
 _client_cache = {}