fix bug

py-client/sdk/trade.py

@@ -15,15 +15,20 @@ class TradeMixin:
     def passorder(
         self,
         op_type: int,
-        stock_code: str,
-        volume: int,
+        stock_code: str = "",
+        volume: int = 0,
         order_type: int = ORDER_TYPE_VOLUME,
         pr_type: int = PR_TYPE_LATEST,
         price: float = -1,
         quick_trade: int = QUICK_TRADE_NOW,
         strategy_name: str = "",
         order_id: str = "",
+        stock: str = "",
     ) -> dict[str, Any]:
+        # ``stock`` is retained for compatibility with the original IPO client.
+        stock_code = str(stock_code or stock).strip()
+        if not stock_code:
+            raise ValueError("stock_code cannot be empty")
         return self._post_json(
             "/api/trade/passorder",
             {
@@ -39,6 +44,14 @@ class TradeMixin:
             },
         )
 
+    def ipo_data(self, ipo_type: str = "STOCK") -> list[dict[str, Any]]:
+        """Return today's IPO candidates from the QMT REST service."""
+        response = self._post_json(
+            "/api/trade/ipo_data",
+            {"type": str(ipo_type).strip().upper()},
+        ) or []
+        return response if isinstance(response, list) else []
+
     def passorder_latest(self, side: int, stock_code: str, volume: int) -> dict[str, Any]:
         return self.passorder(side, stock_code, volume)