[QOS] Skip showing unnecessary warning message (sonic-net#3708)

* [QOS] Skip showing unnecessary warning message

Signed-off-by: Vivek Reddy <[email protected]>

Author: vivekrnv

config/main.py

@@ -778,6 +778,8 @@ def storm_control_delete_entry(port_name, storm_type):
 
 
 def _wait_until_clear(tables, interval=0.5, timeout=30, verbose=False):
+    if timeout == 0:
+        return True
     start = time.time()
     empty = False
     app_db = SonicV2Connector(host='127.0.0.1')
@@ -793,6 +795,7 @@ def _wait_until_clear(tables, interval=0.5, timeout=30, verbose=False):
                     click.echo("Some entries matching {} still exist: {}".format(table, keys[0]))
                 time.sleep(interval)
         empty = (non_empty_table_count == 0)
+
     if not empty:
         click.echo("Operation not completed successfully, please save and reload configuration.")
     return empty

tests/config_test.py

@@ -1625,6 +1625,14 @@ def test_qos_wait_until_clear_not_empty(self):
             empty = _wait_until_clear(["BUFFER_POOL_TABLE:*"], 0.5,2)
         assert not empty
 
+    @patch('click.echo')
+    @patch('swsscommon.swsscommon.SonicV2Connector.keys')
+    def test_qos_wait_until_clear_no_timeout(self, mock_keys, mock_echo):
+        from config.main import _wait_until_clear
+        assert _wait_until_clear(["BUFFER_POOL_TABLE:*"], 0.5, 0)
+        mock_keys.assert_not_called()
+        mock_echo.assert_not_called()
+
     @mock.patch('config.main._wait_until_clear')
     def test_qos_clear_no_wait(self, _wait_until_clear):
         from config.main import _clear_qos