Fix bug in stake_amount adjustment

This was preventing a DCA order to take the remaining stake

freqtrade/wallets.py

@@ -297,16 +297,16 @@ class Wallets:
             logger.debug(f"Stake amount is {stake_amount}, ignoring possible trade for {pair}.")
             return 0
 
-        max_stake_amount = min(max_stake_amount, self.get_available_stake_amount())
+        max_allowed_stake = min(max_stake_amount, self.get_available_stake_amount())
         if trade_amount:
             # if in a trade, then the resulting trade size cannot go beyond the max stake
             # Otherwise we could no longer exit.
-            max_stake_amount = min(max_stake_amount, max_stake_amount - trade_amount)
+            max_allowed_stake = min(max_allowed_stake, max_stake_amount - trade_amount)
 
-        if min_stake_amount is not None and min_stake_amount > max_stake_amount:
+        if min_stake_amount is not None and min_stake_amount > max_allowed_stake:
             if self._log:
                 logger.warning("Minimum stake amount > available balance. "
-                               f"{min_stake_amount} > {max_stake_amount}")
+                               f"{min_stake_amount} > {max_allowed_stake}")
             return 0
         if min_stake_amount is not None and stake_amount < min_stake_amount:
             if self._log:
@@ -325,11 +325,11 @@ class Wallets:
                 return 0
             stake_amount = min_stake_amount
 
-        if stake_amount > max_stake_amount:
+        if stake_amount > max_allowed_stake:
             if self._log:
                 logger.info(
                     f"Stake amount for pair {pair} is too big "
-                    f"({stake_amount} > {max_stake_amount}), adjusting to {max_stake_amount}."
+                    f"({stake_amount} > {max_allowed_stake}), adjusting to {max_allowed_stake}."
                 )
-            stake_amount = max_stake_amount
+            stake_amount = max_allowed_stake
         return stake_amount

tests/test_wallets.py

@@ -190,7 +190,7 @@ def test_get_trade_stake_amount_unlimited_amount(default_conf, ticker, balance_r
     (1, 15, 10, 10000, None, 0),  # Below min stake and min_stake > stake_available
     (20, 50, 100, 10000, None, 0),  # Below min stake and stake * 1.3 > min_stake
     (1000, None, 1000, 10000, None, 1000),  # No min-stake-amount could be determined
-    (2000, 15, 2000, 3000, 1500, 500),  # Rebuy - resulting in too high stake amount. Adjusting.
+    (2000, 15, 2000, 3000, 1500, 1500),  # Rebuy - resulting in too high stake amount. Adjusting.
 ])
 def test_validate_stake_amount(
     mocker,