EZSP startup reset corner cases (#587)

* Handle connection reset failure during reconnect

* Close EZSP connection when startup config writing fails

bellows/uart.py

@@ -213,22 +213,21 @@ def connection_lost(self, exc):
         """Port was closed unexpectedly."""
 
         LOGGER.debug("Connection lost: %r", exc)
+        reason = exc or ConnectionResetError("Remote server closed connection")
 
         # XXX: The startup reset future must be resolved with an error *before* the
         # "connection done" future is completed: the secondary thread has an attached
         # callback to stop itself, which will cause the a future to propagate a
         # `CancelledError` into the active event loop, breaking everything!
         if self._startup_reset_future:
-            self._startup_reset_future.set_exception(
-                exc or ConnectionResetError("Remote server closed connection")
-            )
+            self._startup_reset_future.set_exception(reason)
 
         if self._connection_done_future:
             self._connection_done_future.set_result(exc)
             self._connection_done_future = None
 
         if self._reset_future:
-            self._reset_future.cancel()
+            self._reset_future.set_exception(reason)
             self._reset_future = None
 
         if self._send_task:

bellows/zigbee/application.py

@@ -139,12 +139,13 @@ async def connect(self) -> None:
 
         try:
             await ezsp.startup_reset()
+
+            # Writing config is required here because network info can't be loaded
+            await ezsp.write_config(self.config[CONF_EZSP_CONFIG])
         except Exception:
             ezsp.close()
             raise
 
-        # Writing config is required here because network info can't be loaded otherwise
-        await ezsp.write_config(self.config[CONF_EZSP_CONFIG])
         self._ezsp = ezsp
 
     async def _ensure_network_running(self) -> bool:

tests/test_application.py

@@ -1802,7 +1802,7 @@ async def test_connect_failure(
     app: ControllerApplication, ezsp_mock: ezsp.EZSP
 ) -> None:
     """Test that a failure to connect propagates."""
-    ezsp_mock.startup_reset = AsyncMock(side_effect=OSError())
+    ezsp_mock.write_config = AsyncMock(side_effect=OSError())
     ezsp_mock.connect = AsyncMock()
     app._ezsp = None
 

tests/test_uart.py

@@ -388,7 +388,7 @@ def on_transport_close():
 
     asyncio.get_running_loop().call_later(0.1, gw.connection_lost, ValueError())
 
-    with pytest.raises(asyncio.CancelledError):
+    with pytest.raises(ValueError):
         await gw.reset()
 
     # Need to close to release thread