diff --git a/pmd-core/src/test/java/net/sourceforge/pmd/lang/ast/impl/AbstractNodeTest.java b/pmd-core/src/test/java/net/sourceforge/pmd/lang/ast/impl/AbstractNodeTest.java
index 824086f38e..430f6b3dc8 100644
--- a/pmd-core/src/test/java/net/sourceforge/pmd/lang/ast/impl/AbstractNodeTest.java
+++ b/pmd-core/src/test/java/net/sourceforge/pmd/lang/ast/impl/AbstractNodeTest.java
@@ -48,7 +48,7 @@ class AbstractNodeTest {
         return childIndexes;
     }
 
-    static Object childrenAndGrandChildrenIndexes() {
+    static Object[] childrenAndGrandChildrenIndexes() {
         final Integer[] childrenIndexes = childrenIndexes();
         final Integer[] grandChildrenIndexes = grandChildrenIndexes();
         final Object[] indexes = new Object[childrenIndexes.length * grandChildrenIndexes.length];