diff --git a/tests/integration/test_lang/generator.md b/tests/integration/test_lang/generator.md
index 529aab5..187d05a 100644
--- a/tests/integration/test_lang/generator.md
+++ b/tests/integration/test_lang/generator.md
@@ -282,7 +282,7 @@ if TYPE_NAME.startswith('tuple_') or TYPE_NAME.startswith('static_array_'):
 elif TYPE_NAME.startswith('struct_'):
     expect_type_error(
         TYPE + ' must be (u32, ) instead',
-        'The type of the value passed to argument x of function helper should match the type of that argument',
+        'The type of the value passed to argument 0 of function helper should match the type of that argument',
     )
 else:
     expect_type_error(