diff --git a/mapper/response_test.go b/mapper/response_test.go
index 2f918e4..76fd45e 100644
--- a/mapper/response_test.go
+++ b/mapper/response_test.go
@@ -484,7 +484,7 @@
 	err = json.Unmarshal([]byte(expectedOutput), &expectedData)
 
 	assert.Equal(t, expectedData, result)
-
+	assert.Nil(t, err)
 }
 
 // TestResponseMappingAnnotationCreation tests creating new annotations based on RestrictToObligatory