Made borrowed a computed property

freqtrade/persistence/models.py

@@ -269,8 +269,8 @@ class LocalTrade():
     interest_rate: float = 0.0
     liquidation_price: float = None
     is_short: bool = False
-    borrowed: float = 0.0
-    _leverage: float = None  # * You probably want to use LocalTrade.leverage instead
+    _borrowed: float = 0.0
+    leverage: float = None  # * You probably want to use LocalTrade.leverage instead
 
     # @property
     # def base_currency(self) -> str:
@@ -280,7 +280,7 @@ class LocalTrade():
 
     @property
     def amount(self) -> float:
-        if self._leverage is not None:
+        if self.leverage is not None:
             return self._amount * self.leverage
         else:
             return self._amount
@@ -290,22 +290,21 @@ class LocalTrade():
         self._amount = value
 
     @property
-    def leverage(self) -> float:
-        return self._leverage
-
-    @leverage.setter
-    def leverage(self, value):
-        if self.is_short is None or self.amount is None:
-            raise OperationalException(
-                'LocalTrade.amount and LocalTrade.is_short must be assigned before assigning leverage')
-
-        self._leverage = value
+    def borrowed(self) -> float:
+        if self.leverage is not None:
             if self.is_short:
                 # If shorting the full amount must be borrowed
-            self.borrowed = self._amount * value
+                return self._amount * self.leverage
             else:
                 # If not shorting, then the trader already owns a bit
-            self.borrowed = self._amount * (value-1)
+                return self._amount * (self.leverage-1)
+        else:
+            return self._borrowed
+
+    @borrowed.setter
+    def borrowed(self, value):
+        self._borrowed = value
+        self.leverage = None
 
     # End of margin trading properties
 
@@ -897,8 +896,8 @@ class Trade(_DECL_BASE, LocalTrade):
     timeframe = Column(Integer, nullable=True)
 
     # Margin trading properties
-    _leverage: float = None  # * You probably want to use LocalTrade.leverage instead
-    borrowed = Column(Float, nullable=False, default=0.0)
+    leverage: float = None  # * You probably want to use LocalTrade.leverage instead
+    _borrowed = Column(Float, nullable=False, default=0.0)
     interest_rate = Column(Float, nullable=False, default=0.0)
     liquidation_price = Column(Float, nullable=True)
     is_short = Column(Boolean, nullable=False, default=False)