Introduce PlayerDisplayNameChangeEvent (listen only) (#3847)

src/event/player/PlayerDisplayNameChangeEvent.php

@@ -0,0 +1,48 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\event\player;
+
+use pocketmine\player\Player;
+
+class PlayerDisplayNameChangeEvent extends PlayerEvent{
+
+	/** @var string */
+	private $oldName;
+	/** @var string */
+	private $newName;
+
+	public function __construct(Player $player, string $oldName, string $newName){
+		$this->player = $player;
+		$this->oldName = $oldName;
+		$this->newName = $newName;
+	}
+
+	public function getOldName() : string{
+		return $this->oldName;
+	}
+
+	public function getNewName() : string{
+		return $this->newName;
+	}
+}

src/player/Player.php

@@ -52,6 +52,7 @@ use pocketmine\event\player\PlayerChangeSkinEvent;
 use pocketmine\event\player\PlayerChatEvent;
 use pocketmine\event\player\PlayerCommandPreprocessEvent;
 use pocketmine\event\player\PlayerDeathEvent;
+use pocketmine\event\player\PlayerDisplayNameChangeEvent;
 use pocketmine\event\player\PlayerExhaustEvent;
 use pocketmine\event\player\PlayerGameModeChangeEvent;
 use pocketmine\event\player\PlayerInteractEvent;
@@ -622,7 +623,10 @@ class Player extends Human implements CommandSender, ChunkListener, IPlayer{
 	}
 
 	public function setDisplayName(string $name) : void{
-		$this->displayName = $name;
+		$ev = new PlayerDisplayNameChangeEvent($this, $this->displayName, $name);
+		$ev->call();
+
+		$this->displayName = $ev->getNewName();
 	}
 
 	/**