1 files changed, 10 insertions, 0 deletions
diff --git a/src/test/java/org/apache/commons/lang3/builder/DiffBuilderTest.java b/src/test/java/org/apache/commons/lang3/builder/DiffBuilderTest.java
index 705fee26f..003d2abad 100644
--- a/src/test/java/org/apache/commons/lang3/builder/DiffBuilderTest.java
+++ b/src/test/java/org/apache/commons/lang3/builder/DiffBuilderTest.java
@@ -318,6 +318,16 @@ public class DiffBuilderTest extends AbstractLangTest {
     }
 
     @Test
+    public void testNullLhs_4args() {
+        assertThrows(NullPointerException.class, () -> new DiffBuilder<>(null, this, ToStringStyle.DEFAULT_STYLE, true));
+    }
+
+    @Test
+    public void testNullRhs_4args() {
+        assertThrows(NullPointerException.class, () -> new DiffBuilder<>(this, null, ToStringStyle.DEFAULT_STYLE, true));
+    }
+
+    @Test
     public void testObject() {
         final TypeTestClass class1 = new TypeTestClass();
         final TypeTestClass class2 = new TypeTestClass();