diff --git a/typify/tests/schemas/maps_custom.rs b/typify/tests/schemas/maps_custom.rs
index 5094dae0..69034092 100644
--- a/typify/tests/schemas/maps_custom.rs
+++ b/typify/tests/schemas/maps_custom.rs
@@ -1,3 +1,4 @@
+#![deny(warnings)]
 #[doc = r" Error types."]
 pub mod error {
     #[doc = r" Error from a TryFrom or FromStr implementation."]