Fix to get Test and Train Fitness for final solution of Mult-objective Optimization. Fixes PonyGE#166

Author: zahidirfan

src/stats/stats.py

@@ -240,7 +240,7 @@ def get_moo_stats(individuals, end):
         stdout.flush()
 
     # Generate test fitness on regression problems
-    if hasattr(params['FITNESS_FUNCTION'], "training_test") and end:
+    if params["DATASET_TEST"] and end:
 
         for ind in trackers.best_ever:
             # Iterate over all individuals in the first front.
@@ -249,7 +249,10 @@ def get_moo_stats(individuals, end):
             ind.training_fitness = copy(ind.fitness)
 
             # Evaluate test fitness.
-            ind.test_fitness = params['FITNESS_FUNCTION'](ind, dist='test')
+            ind.test_fitness = [
+                func(ind, dist="test")
+                for func in params["FITNESS_FUNCTION"].fitness_functions
+            ]
 
             # Set main fitness as training fitness.
             ind.fitness = ind.training_fitness