diff --git a/test/rustint/core_test.clj b/test/rustint/core_test.clj
index a6d19a2..6e7732b 100644
--- a/test/rustint/core_test.clj
+++ b/test/rustint/core_test.clj
@@ -407,6 +407,16 @@
   )
 )
 
+(deftest convertir-formato-impresion-13
+  (testing "Test 13 convertir-formato-impresion"
+    (is (=
+        (convertir-formato-impresion '("{}{}" "1" ""))
+        '("%s%s" "1" "")
+    ))
+  )
+)
+
+
 
 (deftest get-rust-formatters-01
   (testing "Test 01 get-rust-formatters"