Clear removed values in IntMap

src/com/esotericsoftware/kryo/util/IntMap.java

@@ -195,7 +195,7 @@ public V get (int key) {
 	}
 
 	public V get (int key, @Null V defaultValue) {
-		if (key == 0) return hasZeroValue ? zeroValue : null;
+		if (key == 0) return hasZeroValue ? zeroValue : defaultValue;
 		for (int i = place(key);; i = i + 1 & mask) {
 			int other = keyTable[i];
 			if (other == 0) return defaultValue;
@@ -230,6 +230,7 @@ public V remove (int key) {
 			next = next + 1 & mask;
 		}
 		keyTable[i] = 0;
+		valueTable[i] = null;
 		size--;
 		return oldValue;
 	}
@@ -515,6 +516,7 @@ public void remove () {
 			int i = currentIndex;
 			if (i == INDEX_ZERO && map.hasZeroValue) {
 				map.hasZeroValue = false;
+				map.zeroValue = null;
 			} else if (i < 0) {
 				throw new IllegalStateException("next must be called before remove.");
 			} else {
@@ -531,6 +533,7 @@ public void remove () {
 					next = next + 1 & mask;
 				}
 				keyTable[i] = 0;
+				valueTable[i] = null;
 				if (i != currentIndex) --nextIndex;
 			}
 			currentIndex = INDEX_ILLEGAL;

test/com/esotericsoftware/kryo/util/IntMapTest.java

@@ -0,0 +1,59 @@
+/* Copyright (c) 2008-2026, Nathan Sweet
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following
+ * conditions are met:
+ * 
+ * - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided with the distribution.
+ * - Neither the name of Esoteric Software nor the names of its contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+
+package com.esotericsoftware.kryo.util;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class IntMapTest {
+	// A removed value is not kept in the map, also if it is removed with an iterator or its key is 0.
+	@Test
+	void testRemove () {
+		IntMap<String> map = new IntMap<>();
+		map.put(1, "one");
+		assertEquals("one", map.remove(1));
+		assertFalse(map.containsValue("one", false));
+		assertEquals(-1, map.findKey("one", false, -1));
+
+		map.put(0, "zero");
+		map.put(1, "one");
+		for (IntMap.Entries<String> entries = map.entries(); entries.hasNext();) {
+			entries.next();
+			entries.remove();
+		}
+		assertEquals(0, map.size);
+		assertFalse(map.containsValue("zero", true));
+		assertFalse(map.containsValue("one", false));
+		assertNull(map.put(0, "new"));
+	}
+
+	@Test
+	void testGetDefaultValue () {
+		IntMap<String> map = new IntMap<>();
+		assertEquals("default", map.get(0, "default"));
+		assertEquals("default", map.get(1, "default"));
+		map.put(0, null);
+		map.put(1, null);
+		assertNull(map.get(0, "default"));
+		assertNull(map.get(1, "default"));
+	}
+}