edge: handle properly the 'No trades' case

freqtrade/edge/__init__.py

@@ -139,6 +139,7 @@ class Edge():
 
         # If no trade found then exit
         if len(trades) == 0:
+            logger.info("No trades created.")
             return False
 
         # Fill missing, calculable columns, profit, duration , abs etc.

freqtrade/optimize/edge_cli.py

@@ -73,7 +73,8 @@ class EdgeCli(object):
                         floatfmt=floatfmt, tablefmt="pipe")
 
     def start(self) -> None:
-        self.edge.calculate()
+        result = self.edge.calculate()
+        if result:
             print('')  # blank like for readability
             print(self._generate_edge_table(self.edge._cached_pairs))