async def test_busy_loading_from_pipeline(self, r):
        """
        BusyLoadingErrors should be raised from a pipeline execution
        regardless of the raise_on_error flag.
        """
        pipe = r.pipeline()
        pipe.execute_command("DEBUG", "ERROR", "LOADING fake message")
        with pytest.raises(aioredis.BusyLoadingError):
            await pipe.execute()
        pool = r.connection_pool
        assert not pipe.connection
        assert len(pool._available_connections) == 1
        assert not pool._available_connections[0]._reader

        BusyLoadingErrors should be raised from a pipeline execution
        regardless of the raise_on_error flag.
        
tests/test_connection_pool.py