From 5d769147cac7c97ca384cb6052e6d4cfeb74302c Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Tue, 17 Jul 2018 10:19:36 +0100
Subject: [PATCH 1/3] LevelProviderManager: make addProvider() throw
 InvalidArgumentException instead of LevelException LevelException is not
 useful because it's too generic.

---
 src/pocketmine/level/format/io/LevelProviderManager.php | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/pocketmine/level/format/io/LevelProviderManager.php b/src/pocketmine/level/format/io/LevelProviderManager.php
index 4c8a98ea1..b79184716 100644
--- a/src/pocketmine/level/format/io/LevelProviderManager.php
+++ b/src/pocketmine/level/format/io/LevelProviderManager.php
@@ -27,7 +27,6 @@ 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\level\LevelException;
 
 abstract class LevelProviderManager{
 	protected static $providers = [];
@@ -42,11 +41,11 @@ abstract class LevelProviderManager{
 	/**
 	 * @param string $class
 	 *
-	 * @throws LevelException
+	 * @throws \InvalidArgumentException
 	 */
 	public static function addProvider(string $class){
 		if(!is_subclass_of($class, LevelProvider::class)){
-			throw new LevelException("Class is not a subclass of LevelProvider");
+			throw new \InvalidArgumentException("Class is not a subclass of LevelProvider");
 		}
 		/** @var LevelProvider $class */
 		self::$providers[strtolower($class::getProviderName())] = $class;

From ad1cf38c2131b4e6ea5ada3bfa8cac85bdebab32 Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Tue, 17 Jul 2018 10:50:27 +0100
Subject: [PATCH 2/3] LevelProviderManager: tighten up checks on registering

---
 .../level/format/io/LevelProviderManager.php        | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/pocketmine/level/format/io/LevelProviderManager.php b/src/pocketmine/level/format/io/LevelProviderManager.php
index b79184716..1b42a5eda 100644
--- a/src/pocketmine/level/format/io/LevelProviderManager.php
+++ b/src/pocketmine/level/format/io/LevelProviderManager.php
@@ -44,9 +44,18 @@ abstract class LevelProviderManager{
 	 * @throws \InvalidArgumentException
 	 */
 	public static function addProvider(string $class){
-		if(!is_subclass_of($class, LevelProvider::class)){
-			throw new \InvalidArgumentException("Class is not a subclass of LevelProvider");
+		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");
+		}
+
 		/** @var LevelProvider $class */
 		self::$providers[strtolower($class::getProviderName())] = $class;
 	}

From 40030e98007688d189794078a824fe7d20204905 Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Tue, 17 Jul 2018 10:51:02 +0100
Subject: [PATCH 3/3] added some LevelProviderManager tests

---
 .../level/format/io/AbstractLevelProvider.php | 28 +++++++++++
 .../format/io/InterfaceLevelProvider.php      | 28 +++++++++++
 .../format/io/LevelProviderManagerTest.php    | 47 +++++++++++++++++++
 3 files changed, 103 insertions(+)
 create mode 100644 tests/phpunit/level/format/io/AbstractLevelProvider.php
 create mode 100644 tests/phpunit/level/format/io/InterfaceLevelProvider.php
 create mode 100644 tests/phpunit/level/format/io/LevelProviderManagerTest.php

diff --git a/tests/phpunit/level/format/io/AbstractLevelProvider.php b/tests/phpunit/level/format/io/AbstractLevelProvider.php
new file mode 100644
index 000000000..7f63048e1
--- /dev/null
+++ b/tests/phpunit/level/format/io/AbstractLevelProvider.php
@@ -0,0 +1,28 @@
+<?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\level\format\io;
+
+abstract class AbstractLevelProvider implements LevelProvider{
+
+}
diff --git a/tests/phpunit/level/format/io/InterfaceLevelProvider.php b/tests/phpunit/level/format/io/InterfaceLevelProvider.php
new file mode 100644
index 000000000..e01f08e43
--- /dev/null
+++ b/tests/phpunit/level/format/io/InterfaceLevelProvider.php
@@ -0,0 +1,28 @@
+<?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\level\format\io;
+
+interface InterfaceLevelProvider extends LevelProvider{
+
+}
diff --git a/tests/phpunit/level/format/io/LevelProviderManagerTest.php b/tests/phpunit/level/format/io/LevelProviderManagerTest.php
new file mode 100644
index 000000000..7661de234
--- /dev/null
+++ b/tests/phpunit/level/format/io/LevelProviderManagerTest.php
@@ -0,0 +1,47 @@
+<?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\level\format\io;
+
+use PHPUnit\Framework\TestCase;
+
+class LevelProviderManagerTest extends TestCase{
+
+	public function testAddNonClassProvider() : void{
+		$this->expectException(\InvalidArgumentException::class);
+
+		LevelProviderManager::addProvider("lol");
+	}
+
+	public function testAddAbstractClassProvider() : void{
+		$this->expectException(\InvalidArgumentException::class);
+
+		LevelProviderManager::addProvider(AbstractLevelProvider::class);
+	}
+
+	public function testAddInterfaceProvider() : void{
+		$this->expectException(\InvalidArgumentException::class);
+
+		LevelProviderManager::addProvider(InterfaceLevelProvider::class);
+	}
+}