Don't add an empty transition for PHENOTYPES

casq/simplify.py

@@ -92,10 +92,11 @@ def handle_phenotypes(info):
                 modifiers.append(("INHIBITION", t.reactants[0]))
             else:
                 modifiers.append(("CATALYSIS", t.reactants[0]))
-        new_transitions.append(
-            Transition("STATE_TRANSITION", [], modifiers, None, None)
-        )
-        info[key]["transitions"] = new_transitions
+        if modifiers:
+            new_transitions.append(
+                Transition("STATE_TRANSITION", [], modifiers, None, None)
+            )
+            info[key]["transitions"] = new_transitions
 
 
 def delete_complexes_and_store_multispecies(info):