fix the deleting method

data-structures/src/test/java/com/baeldung/circularlinkedlist/CircularLinkedListUnitTest.java

@@ -1,10 +1,10 @@
 package com.baeldung.circularlinkedlist;
 
+import org.junit.Test;
+
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
-import org.junit.Test;
-
 public class CircularLinkedListUnitTest {
 
     @Test
@@ -23,7 +23,7 @@ public class CircularLinkedListUnitTest {
     }
 
     @Test
-    public void givenACircularLinkedList_WhenDeletingElements_ThenListDoesNotContainThoseElements() {
+    public void givenACircularLinkedList_WhenDeletingInOrderHeadMiddleTail_ThenListDoesNotContainThoseElements() {
         CircularLinkedList cll = createCircularLinkedList();
 
         assertTrue(cll.containsNode(13));
@@ -39,6 +39,32 @@ public class CircularLinkedListUnitTest {
         assertFalse(cll.containsNode(46));
     }
 
+    @Test
+    public void givenACircularLinkedList_WhenDeletingInOrderTailMiddleHead_ThenListDoesNotContainThoseElements() {
+        CircularLinkedList cll = createCircularLinkedList();
+
+        assertTrue(cll.containsNode(46));
+        cll.deleteNode(46);
+        assertFalse(cll.containsNode(46));
+
+        assertTrue(cll.containsNode(1));
+        cll.deleteNode(1);
+        assertFalse(cll.containsNode(1));
+
+        assertTrue(cll.containsNode(13));
+        cll.deleteNode(13);
+        assertFalse(cll.containsNode(13));
+    }
+
+    @Test
+    public void givenACircularLinkedListWithOneNode_WhenDeletingElement_ThenListDoesNotContainTheElement() {
+        CircularLinkedList cll = new CircularLinkedList();
+        cll.addNode(1);
+        cll.deleteNode(1);
+        assertFalse(cll.containsNode(1));
+    }
+
+
     private CircularLinkedList createCircularLinkedList() {
         CircularLinkedList cll = new CircularLinkedList();