Update to latest PHP 8.1 syntax

src/ConsoleHelper.php

@@ -56,7 +56,7 @@ class ConsoleHelper
     /** @var resource Exists only for testing. */
     private $stderr = STDERR;
 
-    private bool $supportsColor;
+    private readonly bool $supportsColor;
 
     /**
      * @param resource $resource

test/FastPriorityQueueTest.php

@@ -22,7 +22,7 @@
 class FastPriorityQueueTest extends TestCase
 {
     /** @var FastPriorityQueue<string> */
-    private FastPriorityQueue $queue;
+    private readonly FastPriorityQueue $queue;
 
     /** @var string[] */
     private array $expected;
@@ -30,7 +30,7 @@
     protected function setUp(): void
     {
         /** @psalm-var FastPriorityQueue<string> $this->queue */
         $this->queue = new FastPriorityQueue();
         $this->insertDataQueue($this->queue);
         $this->expected = [
             'test1',

test/PriorityQueueTest.php

@@ -20,12 +20,12 @@
 class PriorityQueueTest extends TestCase
 {
     /** @var PriorityQueue<string, int> */
-    private PriorityQueue $queue;
+    private readonly PriorityQueue $queue;
 
     protected function setUp(): void
     {
         /** @psalm-var PriorityQueue<string, int> $this->queue */
         $this->queue = new PriorityQueue();
         $this->queue->insert('foo', 3);
         $this->queue->insert('bar', 4);
         $this->queue->insert('baz', 2);

test/StaticAnalysis/PriorityQueueGenericsCanBeUnderstood.php

@@ -14,7 +14,7 @@ final class PriorityQueueGenericsCanBeUnderstood
     /**
      * @param PriorityQueue<string, int> $laminas
      */
-    public function __construct(private PriorityQueue $laminas)
+    public function __construct(private readonly PriorityQueue $laminas)
     {
     }
 

test/StaticAnalysis/SplPriorityQueueGenericsCanBeUnderstood.php

@@ -14,7 +14,7 @@ final class SplPriorityQueueGenericsCanBeUnderstood
     /**
      * @param SplPriorityQueue<string, int> $laminas
      */
-    public function __construct(private SplPriorityQueue $laminas)
+    public function __construct(private readonly SplPriorityQueue $laminas)
     {
     }