diff --git a/src/lib.rs b/src/lib.rs
index ebd0de2..56914c1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1496,7 +1496,7 @@ mod tests {
             }
 
             Err(why) => {
-                panic!(why)
+                panic!("{}", why)
             }
         }
     }