Add compatibility code for existing informative_pairs implementation

freqtrade/strategy/interface.py

@@ -422,6 +422,8 @@ class IStrategy(ABC, HyperStrategyMixin):
         Internal method which gathers all informative pairs (user or automatically defined).
         """
         informative_pairs = self.informative_pairs()
+        # Compatibility code for 2 tuple informative pairs
+        informative_pairs = [(p[0], p[1], p[2] if len(p) > 2 else '') for p in informative_pairs]
         for inf_data, _ in self._ft_informative:
             if inf_data.asset:
                 pair_tf = (

tests/strategy/strats/informative_decorator_strategy.py

@@ -19,7 +19,8 @@ class InformativeDecoratorTest(IStrategy):
     startup_candle_count: int = 20
 
     def informative_pairs(self):
-        return [('NEO/USDT', '5m', '')]
+        # Intentionally return 2 tuples, must be converted to 3 in compatibility code
+        return [('NEO/USDT', '5m')]
 
     def populate_buy_trend(self, dataframe: DataFrame, metadata: dict) -> DataFrame:
         dataframe['buy'] = 0