[VarDumper] Add types to private properties

Author: derrabus

Caster/ArgsStub.php

@@ -20,7 +20,7 @@
  */
 class ArgsStub extends EnumStub
 {
-    private static $parameters = [];
+    private static array $parameters = [];
 
     public function __construct(array $args, string $function, ?string $class)
     {

Caster/ExceptionCaster.php

@@ -44,7 +44,7 @@ class ExceptionCaster
         \E_STRICT => 'E_STRICT',
     ];
 
-    private static $framesCache = [];
+    private static array $framesCache = [];
 
     public static function castError(\Error $e, array $a, Stub $stub, bool $isNested, int $filter = 0)
     {

Caster/LinkStub.php

@@ -20,8 +20,8 @@ class LinkStub extends ConstStub
 {
     public $inVendor = false;
 
-    private static $vendorRoots;
-    private static $composerRoots;
+    private static array $vendorRoots;
+    private static array $composerRoots = [];
 
     public function __construct(string $label, int $line = 0, string $href = null)
     {
@@ -65,7 +65,7 @@ public function __construct(string $label, int $line = 0, string $href = null)
 
     private function getComposerRoot(string $file, bool &$inVendor)
     {
-        if (null === self::$vendorRoots) {
+        if (!isset(self::$vendorRoots)) {
             self::$vendorRoots = [];
 
             foreach (get_declared_classes() as $class) {

Caster/MemcachedCaster.php

@@ -20,8 +20,8 @@
  */
 class MemcachedCaster
 {
-    private static $optionConstants;
-    private static $defaultOptions;
+    private static array $optionConstants;
+    private static array $defaultOptions;
 
     public static function castMemcached(\Memcached $c, array $a, Stub $stub, bool $isNested)
     {

Cloner/AbstractCloner.php

@@ -196,15 +196,15 @@ abstract class AbstractCloner implements ClonerInterface
     /**
      * @var array<string, list<callable>>
      */
-    private $casters = [];
+    private array $casters = [];
 
     /**
      * @var callable|null
      */
     private $prevErrorHandler;
 
-    private $classInfo = [];
-    private $filter = 0;
+    private array $classInfo = [];
+    private int $filter = 0;
 
     /**
      * @param callable[]|null $casters A map of casters

Cloner/Data.php

@@ -19,13 +19,13 @@
  */
 class Data implements \ArrayAccess, \Countable, \IteratorAggregate
 {
-    private $data;
-    private $position = 0;
-    private $key = 0;
-    private $maxDepth = 20;
-    private $maxItemsPerDepth = -1;
-    private $useRefHandles = -1;
-    private $context = [];
+    private array $data;
+    private int $position = 0;
+    private int|string $key = 0;
+    private int $maxDepth = 20;
+    private int $maxItemsPerDepth = -1;
+    private int $useRefHandles = -1;
+    private array $context = [];
 
     /**
      * @param array $data An array as returned by ClonerInterface::cloneVar()

Cloner/Stub.php

@@ -39,7 +39,7 @@ class Stub
     public $position = 0;
     public $attr = [];
 
-    private static $defaultProperties = [];
+    private static array $defaultProperties = [];
 
     /**
      * @internal

Cloner/VarCloner.php

@@ -16,8 +16,8 @@
  */
 class VarCloner extends AbstractCloner
 {
-    private static $gid;
-    private static $arrayCache = [];
+    private static string $gid;
+    private static array $arrayCache = [];
 
     /**
      * {@inheritdoc}
@@ -44,9 +44,7 @@ protected function doClone(mixed $var): array
         $stub = null;                   // Stub capturing the main properties of an original item value
                                         // or null if the original value is used directly
 
-        if (!$gid = self::$gid) {
-            $gid = self::$gid = md5(random_bytes(6)); // Unique string used to detect the special $GLOBALS variable
-        }
+        $gid = self::$gid ??= md5(random_bytes(6)); // Unique string used to detect the special $GLOBALS variable
         $arrayStub = new Stub();
         $arrayStub->type = Stub::TYPE_ARRAY;
         $fromObjCast = false;

Command/Descriptor/CliDescriptor.php

@@ -26,8 +26,8 @@
  */
 class CliDescriptor implements DumpDescriptorInterface
 {
-    private $dumper;
-    private $lastIdentifier;
+    private CliDumper $dumper;
+    private mixed $lastIdentifier = null;
 
     public function __construct(CliDumper $dumper)
     {

Command/Descriptor/HtmlDescriptor.php

@@ -24,8 +24,8 @@
  */
 class HtmlDescriptor implements DumpDescriptorInterface
 {
-    private $dumper;
-    private $initialized = false;
+    private HtmlDumper $dumper;
+    private bool $initialized = false;
 
     public function __construct(HtmlDumper $dumper)
     {