Add testcase for empty-order case

tests/test_freqtradebot.py

@@ -2089,6 +2089,29 @@ def test_handle_timedout_limit_buy(mocker, default_conf, limit_buy_order) -> Non
     assert cancel_order_mock.call_count == 1
 
 
+def test_handle_timedout_limit_buy_corder_empty(mocker, default_conf, limit_buy_order) -> None:
+    patch_RPCManager(mocker)
+    patch_exchange(mocker)
+    cancel_order_mock = MagicMock(return_value={})
+    mocker.patch.multiple(
+        'freqtrade.exchange.Exchange',
+        cancel_order=cancel_order_mock
+    )
+
+    freqtrade = FreqtradeBot(default_conf)
+
+    Trade.session = MagicMock()
+    trade = MagicMock()
+    limit_buy_order['remaining'] = limit_buy_order['amount']
+    assert freqtrade.handle_timedout_limit_buy(trade, limit_buy_order)
+    assert cancel_order_mock.call_count == 1
+
+    cancel_order_mock.reset_mock()
+    limit_buy_order['amount'] = 2
+    assert not freqtrade.handle_timedout_limit_buy(trade, limit_buy_order)
+    assert cancel_order_mock.call_count == 1
+
+
 def test_handle_timedout_limit_sell(mocker, default_conf) -> None:
     patch_RPCManager(mocker)
     patch_exchange(mocker)