fix(rules): trait and racial are non-stacking bonus types (APG Traits, CRB Combining Magic Effects)

tests/test_effects.py

@@ -19,20 +19,6 @@ class TestStackingTypes:
         ]
         assert resolve_modifiers(mods) == 3
 
-    def test_two_racial_bonus_stack(self) -> None:
-        mods = [
-            StatModifier("save", 1, "racial"),
-            StatModifier("save", 1, "racial"),
-        ]
-        assert resolve_modifiers(mods) == 2
-
-    def test_two_trait_bonus_stack(self) -> None:
-        mods = [
-            StatModifier("attack", 1, "trait"),
-            StatModifier("attack", 1, "trait"),
-        ]
-        assert resolve_modifiers(mods) == 2
-
     def test_two_untyped_bonus_stack(self) -> None:
         mods = [
             StatModifier("attack", 1),
@@ -43,8 +29,8 @@ class TestStackingTypes:
     def test_mixed_stacking_types_all_sum(self) -> None:
         mods = [
             StatModifier("ac", 1, "dodge"),
-            StatModifier("ac", 2, "racial"),
-            StatModifier("ac", 1, "trait"),
+            StatModifier("ac", 2, "dodge"),
+            StatModifier("ac", 1),
             StatModifier("ac", 1),
         ]
         assert resolve_modifiers(mods) == 5
@@ -101,6 +87,23 @@ class TestNonStackingTypes:
         ]
         assert resolve_modifiers(mods) == 2
 
+    def test_two_racial_bonus_do_not_stack(self) -> None:
+        # CRB "Combining Magic Effects": "two bonuses of the same type don't
+        # stack" — racial is a named type.
+        mods = [
+            StatModifier("save", 1, "racial"),
+            StatModifier("save", 2, "racial"),
+        ]
+        assert resolve_modifiers(mods) == 2
+
+    def test_two_trait_bonus_do_not_stack(self) -> None:
+        # APG "Traits": "Trait bonuses do not stack".
+        mods = [
+            StatModifier("attack", 1, "trait"),
+            StatModifier("attack", 2, "trait"),
+        ]
+        assert resolve_modifiers(mods) == 2
+
 
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