Added a unit test to ensure valid format of MINECRAFT_VERSION_NETWORK

tests/phpunit/network/mcpe/protocol/ProtocolInfoTest.php

@@ -0,0 +1,37 @@
+<?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\network\mcpe\protocol;
+
+use PHPUnit\Framework\TestCase;
+
+final class ProtocolInfoTest extends TestCase{
+
+	public function testMinecraftVersionNetwork() : void{
+		self::assertMatchesRegularExpression(
+			'/^(?:\d+\.)?(?:\d+\.)?(?:\d+\.)?\d+$/',
+			ProtocolInfo::MINECRAFT_VERSION_NETWORK,
+			"Network version should only contain 0-9 and \".\", and no more than 4 groups of digits"
+		);
+	}
+}