1 files changed, 80 insertions, 0 deletions
diff --git a/src/test/java/org/apache/commons/lang3/reflect/InheritanceUtilsTest.java b/src/test/java/org/apache/commons/lang3/reflect/InheritanceUtilsTest.java
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index 000000000..bb32c48b9
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+++ b/src/test/java/org/apache/commons/lang3/reflect/InheritanceUtilsTest.java
@@ -0,0 +1,80 @@
+/*
+ * 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.
+ */
+package org.apache.commons.lang3.reflect;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import org.apache.commons.lang3.AbstractLangTest;
+import org.apache.commons.lang3.reflect.testbed.AnotherChild;
+import org.apache.commons.lang3.reflect.testbed.AnotherParent;
+import org.apache.commons.lang3.reflect.testbed.Grandchild;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Unit tests InheritanceUtils
+ */
+public class InheritanceUtilsTest extends AbstractLangTest {
+
+    @Test
+    public void testConstructor() throws Exception {
+        assertNotNull(InheritanceUtils.class.newInstance());
+    }
+
+    @Test
+    public void testDistanceGreaterThanZero() {
+        assertEquals(1, InheritanceUtils.distance(AnotherChild.class, AnotherParent.class));
+        assertEquals(1, InheritanceUtils.distance(Grandchild.class, AnotherChild.class));
+        assertEquals(2, InheritanceUtils.distance(Grandchild.class, AnotherParent.class));
+        assertEquals(3, InheritanceUtils.distance(Grandchild.class, Object.class));
+    }
+
+    @Test
+    public void testDistanceEqual() {
+        assertEquals(0, InheritanceUtils.distance(AnotherChild.class, AnotherChild.class));
+    }
+
+    @Test
+    public void testDistanceEqualObject() {
+        assertEquals(0, InheritanceUtils.distance(Object.class, Object.class));
+    }
+
+    @Test
+    public void testDistanceNullChild() {
+        assertEquals(-1, InheritanceUtils.distance(null, Object.class));
+    }
+
+    @Test
+    public void testDistanceNullParent() {
+        assertEquals(-1, InheritanceUtils.distance(Object.class, null));
+    }
+
+    @Test
+    public void testDistanceNullParentNullChild() {
+        assertEquals(-1, InheritanceUtils.distance(null, null));
+    }
+
+    @Test
+    public void testDistanceDisjoint() {
+        assertEquals(-1, InheritanceUtils.distance(Boolean.class, String.class));
+    }
+
+    @Test
+    public void testDistanceReverseParentChild() {
+        assertEquals(-1, InheritanceUtils.distance(Object.class, Grandchild.class));
+    }
+}