From 2cdf3b0ba885f3b800ae475ebadf551729036c15 Mon Sep 17 00:00:00 2001
From: Stephen Colebourne <scolebourne@apache.org>
Date: Sat, 16 Jul 2005 14:19:42 +0000
Subject: [PATCH] Fix CursorableLinkedList iterator remove/set not throwing
 IllegalStateException after next-previous-removeByIndex bug 35766

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@219330 13f79535-47bb-0310-9956-ffa450edef68
---
 RELEASE-NOTES.html                            |  1 +
 .../list/CursorableLinkedList.java            | 10 ++-
 .../list/TestCursorableLinkedList.java        | 73 ++++++++++++++++++-
 3 files changed, 82 insertions(+), 2 deletions(-)

diff --git a/RELEASE-NOTES.html b/RELEASE-NOTES.html
index 8b29e0dc9..175dd891a 100644
--- a/RELEASE-NOTES.html
+++ b/RELEASE-NOTES.html
@@ -74,6 +74,7 @@ If this causes major headaches to anyone please contact commons-dev at jakarta.a
 <ul>
 <li>FastArrayList - Fix iterators and views to work better in multithreaded environments</li>
 <li>FastArrayList - Fix iterator remove where ConcurrentModificationException not as expected [34690]</li>
+<li>CursorableLinkedList (list subpackage) - Fix iterator remove/set not throwing IllegalStateException after next-previous-removeByIndex [35766]</li>
 <li>SetUniqueList.set(int,Object) - Destroyed set status in certain circumstances [33294]</li>
 <li>AbstractLinkedMap.init() - Now calls createEntry() to create the map entry object [33706]</li>
 <li>AbstractHashedMap deserialization - Fix to prevent doubling of internal data array [34265]</li>
diff --git a/src/java/org/apache/commons/collections/list/CursorableLinkedList.java b/src/java/org/apache/commons/collections/list/CursorableLinkedList.java
index 4b8181bca..cc68b765e 100644
--- a/src/java/org/apache/commons/collections/list/CursorableLinkedList.java
+++ b/src/java/org/apache/commons/collections/list/CursorableLinkedList.java
@@ -445,9 +445,17 @@ public class CursorableLinkedList extends AbstractLinkedList implements Serializ
          * @param node  the node that was removed
          */
         protected void nodeRemoved(Node node) {
-            if (node == next) {
+            if (node == next && node == current) {
+                // state where next() followed by previous()
+                next = node.next;
+                current = null;
+            } else if (node == next) {
+                // state where next() not followed by previous()
+                // and we are matching next node
                 next = node.next;
             } else if (node == current) {
+                // state where next() not followed by previous()
+                // and we are matching current (last returned) node
                 current = null;
                 nextIndex--;
             } else {
diff --git a/src/test/org/apache/commons/collections/list/TestCursorableLinkedList.java b/src/test/org/apache/commons/collections/list/TestCursorableLinkedList.java
index aa24e7f50..b2a9f7a97 100644
--- a/src/test/org/apache/commons/collections/list/TestCursorableLinkedList.java
+++ b/src/test/org/apache/commons/collections/list/TestCursorableLinkedList.java
@@ -444,7 +444,78 @@ public class TestCursorableLinkedList extends TestAbstractLinkedList {
         assertEquals(1, c1.nextIndex());
         assertEquals("0", c1.next());
     }
-    
+
+    //-----------------------------------------------------------------------
+    public void testInternalState_CursorNextNextPreviousRemoveIndex1ByList() {
+        list.add("A");
+        list.add("B");
+        list.add("C");
+
+        CursorableLinkedList.Cursor c1 = list.cursor();
+        assertEquals("A", c1.next());
+        assertEquals("B", c1.next());
+        assertEquals("B", c1.previous());
+        
+        assertEquals("B", list.remove(1));
+        
+        assertEquals(true, c1.nextIndexValid);
+        assertEquals(1, c1.nextIndex);
+        assertEquals(null, c1.current);
+        assertEquals("C", c1.next.value);
+    }
+
+    public void testInternalState_CursorNextRemoveIndex1ByList() {
+        list.add("A");
+        list.add("B");
+        list.add("C");
+
+        CursorableLinkedList.Cursor c1 = list.cursor();
+        assertEquals("A", c1.next());
+        
+        assertEquals("B", list.remove(1));
+        
+        assertEquals(true, c1.nextIndexValid);
+        assertEquals(1, c1.nextIndex);
+        assertEquals("A", c1.current.value);
+        assertEquals("C", c1.next.value);
+    }
+
+    public void testInternalState_CursorNextNextRemoveIndex1ByList() {
+        list.add("A");
+        list.add("B");
+        list.add("C");
+
+        CursorableLinkedList.Cursor c1 = list.cursor();
+        assertEquals("A", c1.next());
+        assertEquals("B", c1.next());
+        
+        assertEquals("B", list.remove(1));
+        
+        assertEquals(true, c1.nextIndexValid);
+        assertEquals(1, c1.nextIndex);
+        assertEquals(null, c1.current);
+        assertEquals("C", c1.next.value);
+    }
+
+    public void testInternalState_CursorNextNextNextRemoveIndex1ByList() {
+        list.add("A");
+        list.add("B");
+        list.add("C");
+        list.add("D");
+
+        CursorableLinkedList.Cursor c1 = list.cursor();
+        assertEquals("A", c1.next());
+        assertEquals("B", c1.next());
+        assertEquals("C", c1.next());
+        
+        assertEquals("B", list.remove(1));
+        
+        assertEquals(false, c1.nextIndexValid);
+        assertEquals("C", c1.current.value);
+        assertEquals("D", c1.next.value);
+    }
+
+    //-----------------------------------------------------------------------
     public void testEqualsAndHashCode() {
         assertTrue(list.equals(list));
         assertEquals(list.hashCode(),list.hashCode());