Fix ServiceBrowser infinite looping when zeroconf is closed before its canceled

bdraco · bdraco · commit ad4a872ee9ac · 2021-10-10T11:31:22.000-10:00
- If the ServiceBrowser was not canceled before Zeroconf was closed
  out, and it was not started by Zeroconf itself, it could lead
  to an infinite scheduling loop
diff --git a/zeroconf/_services/browser.py b/zeroconf/_services/browser.py
@@ -465,9 +465,6 @@ def reschedule_type(self, type_: str, next_time: float) -> None:
 
     def _async_send_ready_queries(self) -> None:
         """Send any ready queries."""
-        if self.done or self.zc.done:
-            return
-
         outs = self._generate_ready_queries(self._first_request)
         if outs:
             self._first_request = False
@@ -476,6 +473,8 @@ def _async_send_ready_queries(self) -> None:
 
     def _async_send_ready_queries_schedule_next(self) -> None:
         """Send ready queries and schedule next one."""
+        if self.done or self.zc.done:
+            return
         self._async_send_ready_queries()
         self._async_schedule_next()
 
