diff --git a/src/Lucene.Net.Tests/Util/TestExceptionExtensions.cs b/src/Lucene.Net.Tests/Util/TestExceptionExtensions.cs
new file mode 100644
index 0000000000..6b499b3cbf
--- /dev/null
+++ b/src/Lucene.Net.Tests/Util/TestExceptionExtensions.cs
@@ -0,0 +1,76 @@
+using NUnit.Framework;
+using System;
+using System.Linq;
+
+#nullable enable
+
+namespace Lucene.Net.Util
+{
+    /*
+     * Licensed to the Apache Software Foundation (ASF) under one or more
+     * contributor license agreements.  See the NOTICE file distributed with
+     * this work for additional information regarding copyright ownership.
+     * The ASF licenses this file to You under the Apache License, Version 2.0
+     * (the "License"); you may not use this file except in compliance with
+     * the License.  You may obtain a copy of the License at
+     *
+     *     http://www.apache.org/licenses/LICENSE-2.0
+     *
+     * Unless required by applicable law or agreed to in writing, software
+     * distributed under the License is distributed on an "AS IS" BASIS,
+     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     * See the License for the specific language governing permissions and
+     * limitations under the License.
+     */
+
+    /// <summary>
+    /// Tests for <see cref="ExceptionExtensions"/>
+    /// </summary>
+    [TestFixture]
+    public class TestExceptionExtensions : LuceneTestCase
+    {
+        [Test]
+        public void TestAddSuppressed()
+        {
+            var e = new Exception("main");
+            var suppressed1 = new Exception("suppressed1");
+            var suppressed2 = new Exception("suppressed2");
+
+            e.AddSuppressed(suppressed1);
+            e.AddSuppressed(suppressed2);
+
+            Assert.AreEqual(2, e.GetSuppressed().Length);
+            Assert.IsTrue(e.GetSuppressed().Any(i => i.Message == suppressed1.Message));
+            Assert.IsTrue(e.GetSuppressed().Any(i => i.Message == suppressed2.Message));
+
+            // test GetSuppressedAsList
+            Assert.AreEqual(2, e.GetSuppressedAsList().Count);
+            Assert.IsTrue(e.GetSuppressedAsList().Any(i => i.Message == suppressed1.Message));
+            Assert.IsTrue(e.GetSuppressedAsList().Any(i => i.Message == suppressed2.Message));
+
+            // test GetSuppressedAsListOrDefault
+            var listOrDefault = e.GetSuppressedAsListOrDefault();
+            Assert.IsNotNull(listOrDefault);
+            Assert.AreEqual(2, listOrDefault!.Count);
+            Assert.IsTrue(listOrDefault.Any(i => i.Message == suppressed1.Message));
+            Assert.IsTrue(listOrDefault.Any(i => i.Message == suppressed2.Message));
+        }
+
+        [Test]
+        public void TestGetSuppressedAsListOrDefault_InitialStateNull()
+        {
+            var e = new Exception("test");
+            var list = e.GetSuppressedAsListOrDefault();
+            Assert.IsNull(list);
+        }
+
+        [Test]
+        public void TestGetSuppressedAsList_CreatesEmptyList()
+        {
+            var e = new Exception("test");
+            var list = e.GetSuppressedAsList();
+            Assert.IsNotNull(list);
+            Assert.AreEqual(0, list.Count);
+        }
+    }
+}