Fix PrioritizedListenersForEvent when OneTimeListener added

src/PrioritizedListenersForEvent.php

@@ -48,6 +48,7 @@ public function getListeners(): iterable
     private function sortListeners(): void
     {
         $this->isSorted = true;
+        $this->sortedListeners = [];
         krsort($this->listeners, SORT_NUMERIC);
 
         foreach ($this->listeners as $group) {
@@ -66,7 +67,7 @@ private function removeOneTimeListeners(): void
         $this->sortedListeners = array_filter($this->sortedListeners, $filter);
 
         foreach ($this->listeners as $priority => $listeners) {
-            $this->listeners[$priority] = array_filter($this->sortedListeners, $filter);
+            $this->listeners[$priority] = array_filter($listeners, $filter);
         }
     }
 }

src/PrioritizedListenersForEventTest.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace League\Event;
+
+use PHPUnit\Framework\TestCase;
+
+class PrioritizedListenersForEventTest extends TestCase
+{
+    public function testOneTimeListener(): void
+    {
+        $group = new PrioritizedListenersForEvent();
+        $group->addListener(function () {
+            return 1;
+        }, 1);
+        $group->addListener(function () {
+            return 2;
+        }, 2);
+        $group->addListener(new OneTimeListener(function () {
+            return 3;
+        }), 3);
+        $listener1 = $group->getListeners();
+        $this->assertCount(3, $listener1);
+        $this->assertEquals([null, 2, 1], self::inspectListener($listener1));
+
+        $group->addListener(function () {
+            return 4;
+        }, 4);
+        $listener2 = $group->getListeners();
+        $this->assertCount(3, $listener2);
+        $this->assertEquals([4, 2, 1], self::inspectListener($listener2));
+    }
+
+    public static function inspectListener(iterable $listeners): array
+    {
+        $event = new \stdClass();
+        $ret = [];
+        foreach ($listeners as $listener) {
+            $ret[] = $listener($event);
+        }
+        return $ret;
+    }
+}