Update FTX stoploss code to avoid exception for stoploss-market orders

closes #6430, closes #6392

tests/exchange/test_ftx.py

@@ -125,7 +125,7 @@ def test_stoploss_adjust_ftx(mocker, default_conf):
     assert not exchange.stoploss_adjust(1501, order)
 
 
-def test_fetch_stoploss_order(default_conf, mocker, limit_sell_order):
+def test_fetch_stoploss_order_ftx(default_conf, mocker, limit_sell_order):
     default_conf['dry_run'] = True
     order = MagicMock()
     order.myid = 123
@@ -147,9 +147,15 @@ def test_fetch_stoploss_order(default_conf, mocker, limit_sell_order):
     with pytest.raises(InvalidOrderException, match=r"Could not get stoploss order for id X"):
         exchange.fetch_stoploss_order('X', 'TKN/BTC')['status']
 
-    api_mock.fetch_orders = MagicMock(return_value=[{'id': 'X', 'status': 'closed'}])
+    # stoploss Limit order
+    api_mock.fetch_orders = MagicMock(return_value=[
+        {'id': 'X', 'status': 'closed',
+         'info': {
+             'orderId': 'mocked_limit_sell',
+         }}])
     api_mock.fetch_order = MagicMock(return_value=limit_sell_order)
 
+    # No orderId field - no call to fetch_order
     resp = exchange.fetch_stoploss_order('X', 'TKN/BTC')
     assert resp
     assert api_mock.fetch_order.call_count == 1
@@ -158,6 +164,17 @@ def test_fetch_stoploss_order(default_conf, mocker, limit_sell_order):
     assert resp['type'] == 'stop'
     assert resp['status_stop'] == 'triggered'
 
+    # Stoploss market order
+    # Contains no new Order, but "average" instead
+    order = {'id': 'X', 'status': 'closed', 'info': {'orderId': None}, 'average': 0.254}
+    api_mock.fetch_orders = MagicMock(return_value=[order])
+    api_mock.fetch_order.reset_mock()
+    resp = exchange.fetch_stoploss_order('X', 'TKN/BTC')
+    assert resp
+    # fetch_order not called (no regular order ID)
+    assert api_mock.fetch_order.call_count == 0
+    assert order == order
+
     with pytest.raises(InvalidOrderException):
         api_mock.fetch_orders = MagicMock(side_effect=ccxt.InvalidOrder("Order not found"))
         exchange = get_patched_exchange(mocker, default_conf, api_mock, id='ftx')