diff --git a/Tests/Source/TestedClass.swift b/Tests/Source/TestedClass.swift
index 75b7e8e..85392ae 100644
--- a/Tests/Source/TestedClass.swift
+++ b/Tests/Source/TestedClass.swift
@@ -198,3 +198,6 @@ class ClassUsingInnerEnum {
 final class FinalClass {
     var shouldBeIgnoredByCuckoo = true
 }
+
+// should generate a compiler error if `FinalClass` isn't ignored and `MockFinalClass` is generated
+class MockFinalClass {}