TMP

tests/code.py

@@ -6,5 +6,4 @@ def code(arg: Optional[bool]) -> str:
         return "a"
     elif arg is True:
         return "b"
-    else:
-        return "c"
+    return "c"

tests/test_code.py

@@ -3,6 +3,12 @@ import pytest
 from . import code
 
 
-@pytest.mark.parametrize("arg, expected", [(None, "a")])
+@pytest.mark.parametrize(
+    "arg, expected",
+    [
+        (None, "a"),
+        (True, "b"),
+    ],
+)
 def test_code(arg, expected):
     assert code.code(arg) == expected