Extract contracts_to_amount and amount_to_contracts to standalone functions

freqtrade/exchange/exchange.py

@@ -408,7 +408,7 @@ class Exchange:
         else:
             return DataFrame()
 
-    def _get_contract_size(self, pair: str) -> float:
+    def get_contract_size(self, pair: str) -> float:
         if self.trading_mode == TradingMode.FUTURES:
             market = self.markets[pair]
             contract_size: float = 1.0
@@ -421,7 +421,7 @@ class Exchange:
 
     def _trades_contracts_to_amount(self, trades: List) -> List:
         if len(trades) > 0 and 'symbol' in trades[0]:
-            contract_size = self._get_contract_size(trades[0]['symbol'])
+            contract_size = self.get_contract_size(trades[0]['symbol'])
             if contract_size != 1:
                 for trade in trades:
                     trade['amount'] = trade['amount'] * contract_size
@@ -429,7 +429,7 @@ class Exchange:
 
     def _order_contracts_to_amount(self, order: Dict) -> Dict:
         if 'symbol' in order and order['symbol'] is not None:
-            contract_size = self._get_contract_size(order['symbol'])
+            contract_size = self.get_contract_size(order['symbol'])
             if contract_size != 1:
                 for prop in self._ft_has.get('order_props_in_contracts', []):
                     if prop in order and order[prop] is not None:
@@ -438,19 +438,13 @@ class Exchange:
 
     def _amount_to_contracts(self, pair: str, amount: float) -> float:
 
-        contract_size = self._get_contract_size(pair)
-        if contract_size and contract_size != 1:
-            return amount / contract_size
-        else:
-            return amount
+        contract_size = self.get_contract_size(pair)
+        return amount_to_contracts(amount, contract_size)
 
     def _contracts_to_amount(self, pair: str, num_contracts: float) -> float:
 
-        contract_size = self._get_contract_size(pair)
-        if contract_size and contract_size != 1:
-            return num_contracts * contract_size
-        else:
-            return num_contracts
+        contract_size = self.get_contract_size(pair)
+        return contracts_to_amount(num_contracts, contract_size)
 
     def set_sandbox(self, api: ccxt.Exchange, exchange_config: dict, name: str) -> None:
         if exchange_config.get('sandbox'):
@@ -2898,6 +2892,33 @@ def market_is_active(market: Dict) -> bool:
     return market.get('active', True) is not False
 
 
+def amount_to_contracts(amount: float, contract_size: float) -> float:
+    """
+    Convert amount to contracts.
+    :param amount: amount to convert
+    :param contract_size: contract size - taken from exchange.get_contract_size(pair)
+    :return: num-contracts
+    """
+    if contract_size and contract_size != 1:
+        return amount / contract_size
+    else:
+        return amount
+
+
+def contracts_to_amount(num_contracts: float, contract_size: float) -> float:
+    """
+    Takes num-contracts and converts it to contract size
+    :param num_contracts: number of contracts
+    :param contract_size: contract size - taken from exchange.get_contract_size(pair)
+    :return: Amount
+    """
+
+    if contract_size and contract_size != 1:
+        return num_contracts * contract_size
+    else:
+        return num_contracts
+
+
 def amount_to_precision(amount: float, amount_precision: Optional[float],
                         precisionMode: Optional[int]) -> float:
     """