test is closer to actual use case

Author: RemDelaporteMathurin

src/festim/exports/vtx.py

@@ -385,7 +385,11 @@ def expression(T, **kwargs):
 
         self.override_signature(expression, reactant_names, product_names)
 
-        reaction_products = reaction.product if isinstance(reaction.product, list) else [reaction.product]
+        reaction_products = (
+            reaction.product
+            if isinstance(reaction.product, list)
+            else [reaction.product]
+        )
 
         super().__init__(
             filename=filename,

test/test_vtx.py

@@ -483,8 +483,8 @@ def test_reaction_rate_override_signature():
 
     rr = F.ReactionRate(reaction=reaction, filename="dummy.bp")
 
-    def my_expression(x, y):
-        return x + y
+    def my_expression(**kwargs):
+        return kwargs.get("x", 0) + kwargs.get("y", 0)
 
     rr.override_signature(my_expression, ["A"], ["B"])
     import inspect