test(okx): add unit test for stop_price_type_value_mapping

tests/exchange/test_okx.py

@@ -4,7 +4,7 @@ from unittest.mock import AsyncMock, MagicMock, PropertyMock
 import ccxt
 import pytest
 
-from freqtrade.enums import CandleType, MarginMode, TradingMode
+from freqtrade.enums import CandleType, MarginMode, PriceType, TradingMode
 from freqtrade.exceptions import RetryableOrderError, TemporaryError
 from freqtrade.exchange.common import API_RETRY_COUNT
 from freqtrade.exchange.exchange import timeframe_to_minutes
@@ -681,6 +681,26 @@ def test__get_stop_params_okx(mocker, default_conf):
     assert params["posSide"] == "net"
 
 
+def test_okx_stop_price_type_mapping(mocker, default_conf):
+    """
+    Test that OKX stop_price_type_value_mapping correctly maps PriceType values.
+    PriceType.MARK should map to "mark", PriceType.INDEX should map to "index".
+    """
+    default_conf["trading_mode"] = "futures"
+    default_conf["margin_mode"] = "isolated"
+    exchange = get_patched_exchange(mocker, default_conf, exchange="okx")
+
+    # Verify the mapping is correct
+    mapping = exchange._ft_has.get("stop_price_type_value_mapping", {})
+
+    assert mapping.get(PriceType.LAST) == "last"
+    assert mapping.get(PriceType.MARK) == "mark"
+    assert mapping.get(PriceType.INDEX) == "index"
+
+    # Verify stop_price_type_field is set correctly
+    assert exchange._ft_has.get("stop_price_type_field") == "slTriggerPxType"
+
+
 def test_fetch_orders_okx(default_conf, mocker, limit_order):
     api_mock = MagicMock()
     api_mock.fetch_orders = MagicMock(