From be37236c7660e1f204a0c6c5dbccb3620c3d48a1 Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Thu, 26 Jul 2018 15:21:03 +0100
Subject: [PATCH] Deduplicate code for general classpath registries

---
 src/pocketmine/entity/Entity.php              | 18 ++++------------
 .../level/format/io/LevelProviderManager.php  | 13 ++----------
 src/pocketmine/tile/Tile.php                  | 15 +++----------
 src/pocketmine/utils/Utils.php                | 21 +++++++++++++++++++
 4 files changed, 30 insertions(+), 37 deletions(-)

diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index 480d38cbf..e2ea69f1a 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/src/pocketmine/entity/Entity.php
@@ -73,6 +73,7 @@ use pocketmine\plugin\Plugin;
 use pocketmine\Server;
 use pocketmine\timings\Timings;
 use pocketmine\timings\TimingsHandler;
+use pocketmine\utils\Utils;
 
 abstract class Entity extends Location implements Metadatable, EntityIds{
 
@@ -304,27 +305,16 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @throws \InvalidArgumentException
 	 */
 	public static function registerEntity(string $className, bool $force = false, array $saveNames = []) : void{
+		Utils::testValidInstance($className, Entity::class);
+
 		/** @var Entity $className */
-
-		try{
-			$class = new \ReflectionClass($className);
-		}catch(\ReflectionException $e){
-			throw new \InvalidArgumentException("Class $className does not exist");
-		}
-		if(!$class->isSubclassOf(Entity::class)){
-			throw new \InvalidArgumentException("Class $className does not extend " . Entity::class);
-		}
-		if(!$class->isInstantiable()){
-			throw new \InvalidArgumentException("Class $className cannot be constructed");
-		}
-
 		if($className::NETWORK_ID !== -1){
 			self::$knownEntities[$className::NETWORK_ID] = $className;
 		}elseif(!$force){
 			throw new \InvalidArgumentException("Class $className does not declare a valid NETWORK_ID and not force-registering");
 		}
 
-		$shortName = $class->getShortName();
+		$shortName = (new \ReflectionClass($className))->getShortName();
 		if(!in_array($shortName, $saveNames, true)){
 			$saveNames[] = $shortName;
 		}
diff --git a/src/pocketmine/level/format/io/LevelProviderManager.php b/src/pocketmine/level/format/io/LevelProviderManager.php
index 1b42a5eda..04f30f168 100644
--- a/src/pocketmine/level/format/io/LevelProviderManager.php
+++ b/src/pocketmine/level/format/io/LevelProviderManager.php
@@ -27,6 +27,7 @@ use pocketmine\level\format\io\leveldb\LevelDB;
 use pocketmine\level\format\io\region\Anvil;
 use pocketmine\level\format\io\region\McRegion;
 use pocketmine\level\format\io\region\PMAnvil;
+use pocketmine\utils\Utils;
 
 abstract class LevelProviderManager{
 	protected static $providers = [];
@@ -44,17 +45,7 @@ abstract class LevelProviderManager{
 	 * @throws \InvalidArgumentException
 	 */
 	public static function addProvider(string $class){
-		try{
-			$reflection = new \ReflectionClass($class);
-		}catch(\ReflectionException $e){
-			throw new \InvalidArgumentException("Class $class does not exist");
-		}
-		if(!$reflection->implementsInterface(LevelProvider::class)){
-			throw new \InvalidArgumentException("Class $class does not implement " . LevelProvider::class);
-		}
-		if(!$reflection->isInstantiable()){
-			throw new \InvalidArgumentException("Class $class cannot be constructed");
-		}
+		Utils::testValidInstance($class, LevelProvider::class);
 
 		/** @var LevelProvider $class */
 		self::$providers[strtolower($class::getProviderName())] = $class;
diff --git a/src/pocketmine/tile/Tile.php b/src/pocketmine/tile/Tile.php
index 78cda5fed..d26849649 100644
--- a/src/pocketmine/tile/Tile.php
+++ b/src/pocketmine/tile/Tile.php
@@ -39,6 +39,7 @@ use pocketmine\Player;
 use pocketmine\Server;
 use pocketmine\timings\Timings;
 use pocketmine\timings\TimingsHandler;
+use pocketmine\utils\Utils;
 
 abstract class Tile extends Position{
 
@@ -114,19 +115,9 @@ abstract class Tile extends Position{
 	 * @param string[] $saveNames
 	 */
 	public static function registerTile(string $className, array $saveNames = []) : void{
-		try{
-			$class = new \ReflectionClass($className);
-		}catch(\ReflectionException $e){
-			throw new \InvalidArgumentException("Class $className does not exist");
-		}
-		if(!$class->isSubclassOf(Tile::class)){
-			throw new \InvalidArgumentException("Class $className does not extend " . Tile::class);
-		}
-		if(!$class->isInstantiable()){
-			throw new \InvalidArgumentException("Class $className cannot be constructed");
-		}
+		Utils::testValidInstance($className, Tile::class);
 
-		$shortName = $class->getShortName();
+		$shortName = (new \ReflectionClass($className))->getShortName();
 		if(!in_array($shortName, $saveNames, true)){
 			$saveNames[] = $shortName;
 		}
diff --git a/src/pocketmine/utils/Utils.php b/src/pocketmine/utils/Utils.php
index fa80a13ac..08552626a 100644
--- a/src/pocketmine/utils/Utils.php
+++ b/src/pocketmine/utils/Utils.php
@@ -547,4 +547,25 @@ class Utils{
 
 		return true; //stfu operator
 	}
+
+	public static function testValidInstance(string $className, string $baseName) : void{
+		try{
+			$base = new \ReflectionClass($baseName);
+		}catch(\ReflectionException $e){
+			throw new \InvalidArgumentException("Base class $baseName does not exist");
+		}
+
+		try{
+			$class = new \ReflectionClass($className);
+		}catch(\ReflectionException $e){
+			throw new \InvalidArgumentException("Class $className does not exist");
+		}
+
+		if(!$class->isSubclassOf($baseName)){
+			throw new \InvalidArgumentException("Class $className does not " . ($base->isInterface() ? "implement" : "extend") . " " . $baseName);
+		}
+		if(!$class->isInstantiable()){
+			throw new \InvalidArgumentException("Class $className cannot be constructed");
+		}
+	}
 }