event: harden APIs that accept arrays

plugin devs can't be relied on to pass the proper types to these APIs, and when the wrong types get passed it makes type errors appear from inside the internals.

src/pocketmine/event/block/SignChangeEvent.php

@@ -26,6 +26,7 @@ namespace pocketmine\event\block;
 use pocketmine\block\Block;
 use pocketmine\event\Cancellable;
 use pocketmine\Player;
+use pocketmine\utils\Utils;
 use function count;
 
 /**
@@ -79,6 +80,7 @@ class SignChangeEvent extends BlockEvent implements Cancellable{
 		if(count($lines) !== 4){
 			throw new \InvalidArgumentException("Array size must be 4!");
 		}
+		Utils::validateArrayValueType($lines, function(string $_) : void{});
 		$this->lines = $lines;
 	}
 

src/pocketmine/event/entity/EntityDeathEvent.php

@@ -25,6 +25,7 @@ namespace pocketmine\event\entity;
 
 use pocketmine\entity\Living;
 use pocketmine\item\Item;
+use pocketmine\utils\Utils;
 
 /**
  * @phpstan-extends EntityEvent<Living>
@@ -62,6 +63,7 @@ class EntityDeathEvent extends EntityEvent{
 	 * @param Item[] $drops
 	 */
 	public function setDrops(array $drops) : void{
+		Utils::validateArrayValueType($drops, function(Item $_) : void{});
 		$this->drops = $drops;
 	}
 

src/pocketmine/event/entity/EntityExplodeEvent.php

@@ -27,6 +27,7 @@ use pocketmine\block\Block;
 use pocketmine\entity\Entity;
 use pocketmine\event\Cancellable;
 use pocketmine\level\Position;
+use pocketmine\utils\Utils;
 
 /**
  * Called when a entity explodes
@@ -67,6 +68,7 @@ class EntityExplodeEvent extends EntityEvent implements Cancellable{
 	 * @param Block[] $blocks
 	 */
 	public function setBlockList(array $blocks) : void{
+		Utils::validateArrayValueType($blocks, function(Block $_) : void{});
 		$this->blocks = $blocks;
 	}
 

src/pocketmine/event/player/PlayerChatEvent.php

@@ -28,6 +28,8 @@ use pocketmine\event\Cancellable;
 use pocketmine\permission\PermissionManager;
 use pocketmine\Player;
 use pocketmine\Server;
+use pocketmine\utils\Utils;
+use function array_values;
 use function spl_object_id;
 
 /**
@@ -97,6 +99,7 @@ class PlayerChatEvent extends PlayerEvent implements Cancellable{
 	 * @param CommandSender[] $recipients
 	 */
 	public function setRecipients(array $recipients) : void{
+		Utils::validateArrayValueType($recipients, function(CommandSender $_) : void{});
 		$this->recipients = $recipients;
 	}
 }

src/pocketmine/event/server/QueryRegenerateEvent.php

@@ -27,6 +27,7 @@ use pocketmine\Player;
 use pocketmine\plugin\Plugin;
 use pocketmine\Server;
 use pocketmine\utils\Binary;
+use pocketmine\utils\Utils;
 use function chr;
 use function count;
 use function str_replace;
@@ -145,6 +146,7 @@ class QueryRegenerateEvent extends ServerEvent{
 	 * @param Plugin[] $plugins
 	 */
 	public function setPlugins(array $plugins) : void{
+		Utils::validateArrayValueType($plugins, function(Plugin $_) : void{});
 		$this->plugins = $plugins;
 		$this->destroyCache();
 	}
@@ -160,6 +162,7 @@ class QueryRegenerateEvent extends ServerEvent{
 	 * @param Player[] $players
 	 */
 	public function setPlayerList(array $players) : void{
+		Utils::validateArrayValueType($players, function(Player $_) : void{});
 		$this->players = $players;
 		$this->destroyCache();
 	}

src/pocketmine/utils/Utils.php

@@ -685,6 +685,21 @@ class Utils{
 		}
 	}
 
+	/**
+	 * @phpstan-template TMemberType
+	 * @phpstan-param array<mixed, TMemberType> $array
+	 * @phpstan-param \Closure(TMemberType) : void $validator
+	 */
+	public static function validateArrayValueType(array $array, \Closure $validator) : void{
+		foreach($array as $k => $v){
+			try{
+				$validator($v);
+			}catch(\TypeError $e){
+				throw new \TypeError("Incorrect type of element at \"$k\": " . $e->getMessage(), 0, $e);
+			}
+		}
+	}
+
 	public static function recursiveUnlink(string $dir) : void{
 		if(is_dir($dir)){
 			$objects = scandir($dir, SCANDIR_SORT_NONE);

tests/phpstan/configs/phpstan-bugs.neon

@@ -35,6 +35,11 @@ parameters:
 			count: 1
 			path: ../../../src/pocketmine/utils/Utils.php
 
+		-
+			message: "#^Parameter \\#1 \\$ of closure expects TMemberType, TMemberType given\\.$#"
+			count: 1
+			path: ../../../src/pocketmine/utils/Utils.php
+
 		-
 			message: "#^Call to static method PHPUnit\\\\Framework\\\\Assert\\:\\:assertNotNull\\(\\) with int and string will always evaluate to true\\.$#"
 			count: 1