From 52039e220d9b485f9f5fb83e0aa56ced73aaf83a Mon Sep 17 00:00:00 2001
From: PJ Fanning <fanningpj@apache.org>
Date: Sun, 29 Sep 2024 07:12:48 +0000
Subject: [PATCH] [bug-69351] fix issues with removing items from IntList

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1921017 13f79535-47bb-0310-9956-ffa450edef68
---
 .../java/org/apache/poi/util/IntList.java     | 12 +++++++--
 .../java/org/apache/poi/util/TestIntList.java | 26 +++++++++++++++++++
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/poi/src/main/java/org/apache/poi/util/IntList.java b/poi/src/main/java/org/apache/poi/util/IntList.java
index 2c6cc86ae6..8d958d5934 100644
--- a/poi/src/main/java/org/apache/poi/util/IntList.java
+++ b/poi/src/main/java/org/apache/poi/util/IntList.java
@@ -18,9 +18,9 @@
 package org.apache.poi.util;
 
 /**
- * A List of int's; as full an implementation of the java.util.List
+ * A List of `int`s; as full an implementation of the java.util.List
  * interface as possible, with an eye toward minimal creation of
- * objects
+ * objects.
  *
  * the mimicry of List is as follows:
  * <ul>
@@ -40,6 +40,8 @@ package org.apache.poi.util;
  *      remove(int index)
  * <li> subList is not supported
  * </ul>
+ *
+ * This class is only meant for internal use in Apache POI.
  */
 public class IntList
 {
@@ -434,6 +436,9 @@ public class IntList
         }
         int rval = _array[ index ];
 
+        if(_limit == _array.length) {
+            growArray(_limit + 1);
+        }
         System.arraycopy(_array, index + 1, _array, index, _limit - index);
         _limit--;
         return rval;
@@ -458,6 +463,9 @@ public class IntList
             if (o == _array[ j ])
             {
                 if (j+1 < _limit) {
+                    if(_limit == _array.length) {
+                        growArray(_limit + 1);
+                    }
                     System.arraycopy(_array, j + 1, _array, j, _limit - j);
                 }
                 _limit--;
diff --git a/poi/src/test/java/org/apache/poi/util/TestIntList.java b/poi/src/test/java/org/apache/poi/util/TestIntList.java
index 4c4317ad0e..6978c7425d 100644
--- a/poi/src/test/java/org/apache/poi/util/TestIntList.java
+++ b/poi/src/test/java/org/apache/poi/util/TestIntList.java
@@ -510,4 +510,30 @@ final class TestIntList {
             assertEquals(a5[j], list.get(j));
         }
     }
+
+    @Test
+    void bug69351() {
+        final int size = 10;
+        final IntList list = new IntList(size);
+        assertEquals(0, list.size());
+        for (int i = 0; i < size; i++) {
+            list.add(i);
+        }
+        assertEquals(size, list.size());
+        assertTrue(list.removeValue(size - 2));
+        assertEquals(size - 1, list.size());
+    }
+
+    @Test
+    void testRemove69351() {
+        final int size = 10;
+        final IntList list = new IntList(size);
+        assertEquals(0, list.size());
+        for (int i = 0; i < size; i++) {
+            list.add(i);
+        }
+        assertEquals(size, list.size());
+        assertEquals(size - 2, list.remove(size - 2));
+        assertEquals(size - 1, list.size());
+    }
 }
-- 
2.39.5