Fix SlotMap::offsetUnset() corrupting mappings when unsetting a slot in a gap (#1660)

CHANGELOG.md

@@ -2,11 +2,14 @@
 
 ## Unreleased
 ### Added
-- Added support for GCRA command (#1657)
-- Handle `-READONLY` responses in Redis Cluster for AWS ElastiCache Redis OSS failover events
+- Added support for `GCRA` command (#1657)
+- Handle Redis Cluster `-READONLY` responses failover events (#1656)
+
 ### Changed
 - Include command name in unsupported container command error messages (#1653)
+
 ### Fixed
+- Fixed handling of gap slots in `SlotMap::offsetUnset()` (#1660)
 
 ## v3.4.2 (2026-03-09)
 ### Changed

src/Cluster/SlotMap.php

@@ -264,6 +264,7 @@ class SlotMap implements ArrayAccess, IteratorAggregate, Countable
         foreach ($this->slotRanges as $slotRange) {
             if (!$slotRange->hasSlot($slot)) {
                 $results[] = $slotRange;
+                continue;
             }
 
             if (static::isValidRange($slotRange->getStart(), $slot - 1)) {

tests/Predis/Cluster/SlotMapTest.php

@@ -403,6 +403,25 @@ class SlotMapTest extends PredisTestCase
         $this->assertFalse(isset($slotmap[5461]));
     }
 
+    /**
+     * @group disconnected
+     */
+    public function testOffsetUnsetDoesNotPolluteSlotMapOnGapSlot(): void
+    {
+        $slotmap = new SlotMap();
+
+        $slotmap->setSlots(0, 100, '127.0.0.1:6379');
+        $slotmap->setSlots(200, 300, '127.0.0.1:6380');
+
+        $this->assertFalse(isset($slotmap[150]));
+        $this->assertNull($slotmap[150]);
+
+        unset($slotmap[150]);
+
+        $this->assertFalse(isset($slotmap[150]));
+        $this->assertNull($slotmap[150]);
+    }
+
     /**
      * @group disconnected
      */