diff --git a/src/test/scala/DeduplicatorTest.scala b/src/test/scala/DeduplicatorTest.scala
index 50d123d..98f1cac 100644
--- a/src/test/scala/DeduplicatorTest.scala
+++ b/src/test/scala/DeduplicatorTest.scala
@@ -5,7 +5,7 @@ class DeduplicatorTest extends AnyFunSuite {
 
   test("Deduplicate given list") {
 
-    val result   = Deduplicator.deduplicate(Array("arg1", "arg2", "arg1", "arg3"))
+    val result   = Deduplicator.deduplicate(Array("arg1", "arg2", "arg1", "arg3", "arg1"))
     val expected = Array("arg1", "arg2", "arg3")
 
     result should contain theSameElementsAs expected