diff --git a/composer.json b/composer.json
index ece19db2..e4b7575c 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
     "inspection"
   ],
   "require-dev": {
-    "php": "^7.1",
+    "php": "^7.4",
     "nikic/php-parser": "^4",
     "phpdocumentor/reflection-docblock": "^4.3",
     "phpunit/phpunit": "^7"
diff --git a/tests/Model/BasePHPClass.php b/tests/Model/BasePHPClass.php
index 2a6bc4b3..081bde97 100644
--- a/tests/Model/BasePHPClass.php
+++ b/tests/Model/BasePHPClass.php
@@ -10,10 +10,10 @@ abstract class BasePHPClass extends BasePHPElement
     /**
      * @var PHPMethod[]
      */
-    public $methods = [];
+    public array $methods = [];
 
     /**
      * @var PHPConst[]
      */
-    public $constants = [];
+    public array $constants = [];
 }
diff --git a/tests/Model/BasePHPElement.php b/tests/Model/BasePHPElement.php
index 643def5f..6e7affd9 100644
--- a/tests/Model/BasePHPElement.php
+++ b/tests/Model/BasePHPElement.php
@@ -3,12 +3,14 @@ declare(strict_types=1);
 
 namespace StubTests\Model;
 
+use Exception;
+
 abstract class BasePHPElement
 {
-    public $name;
-    public $stubBelongsToCore = false;
-    public $parseError;
-    protected $mutedProblems = [];
+    public string $name;
+    public bool $stubBelongsToCore = false;
+    public ?Exception $parseError = null;
+    protected array $mutedProblems = [];
 
     /**
      * @param mixed $object
diff --git a/tests/Model/PHPClass.php b/tests/Model/PHPClass.php
index 77b2a1d5..8c443f35 100644
--- a/tests/Model/PHPClass.php
+++ b/tests/Model/PHPClass.php
@@ -5,15 +5,13 @@ namespace StubTests\Model;
 
 use PhpParser\Node\Stmt\Class_;
 use ReflectionClass;
-use ReflectionClassConstant;
 use ReflectionException;
-use ReflectionMethod;
 use stdClass;
 
 class PHPClass extends BasePHPClass
 {
     public $parentClass;
-    public $interfaces = [];
+    public array $interfaces = [];
 
     /**
      * @param ReflectionClass $clazz
@@ -30,7 +28,6 @@ class PHPClass extends BasePHPClass
             }
             $this->interfaces = $reflectionClass->getInterfaceNames();
 
-            /**@var ReflectionMethod $method */
             foreach ($reflectionClass->getMethods() as $method) {
                 if ($method->getDeclaringClass()->getName() !== $this->name) {
                     continue;
@@ -38,7 +35,6 @@ class PHPClass extends BasePHPClass
                 $this->methods[$method->name] = (new PHPMethod())->readObjectFromReflection($method);
             }
 
-            /**@var ReflectionClassConstant $constant */
             foreach ($reflectionClass->getReflectionConstants() as $constant) {
                 if ($constant->getDeclaringClass()->getName() !== $this->name) {
                     continue;
diff --git a/tests/Model/PHPConst.php b/tests/Model/PHPConst.php
index 6c7be362..75e1d853 100644
--- a/tests/Model/PHPConst.php
+++ b/tests/Model/PHPConst.php
@@ -1,22 +1,21 @@
 <?php
-
 declare(strict_types=1);
 
 namespace StubTests\Model;
 
 use PhpParser\Node\Const_;
+use PhpParser\Node\Expr\UnaryMinus;
 use PhpParser\Node\Stmt\ClassConst;
 use PhpParser\Node\Stmt\Namespace_;
 use PhpParser\NodeAbstract;
 use ReflectionClassConstant;
 use stdClass;
-use PhpParser\Node\Expr\UnaryMinus;
 
 class PHPConst extends BasePHPElement
 {
     use PHPDocElement;
 
-    public $parentName;
+    public ?string $parentName = null;
     public $value;
 
     /**
diff --git a/tests/Model/PHPDocElement.php b/tests/Model/PHPDocElement.php
index ccad1340..88739582 100644
--- a/tests/Model/PHPDocElement.php
+++ b/tests/Model/PHPDocElement.php
@@ -13,22 +13,24 @@ trait PHPDocElement
     /**
      * @var Tag[]
      */
-    public $links = [];
+    public array $links = [];
 
     /**
      * @var Tag[]
      */
-    public $see = [];
+    public array $see = [];
 
     /**
      * @var Tag[]
      */
-    public $sinceTags = [];
+    public array $sinceTags = [];
 
     /**
      * @var Tag[]
      */
-    public $deprecatedTags = [];
+    public array $deprecatedTags = [];
+
+    public bool $hasInternalMetaTag = false;
 
     protected function collectLinks(Node $node): void
     {
@@ -38,7 +40,7 @@ trait PHPDocElement
                 $this->links = $phpDoc->getTagsByName('link');
                 $this->see = $phpDoc->getTagsByName('see');
             } catch (Exception $e) {
-                $this->parseError = $e->getMessage();
+                $this->parseError = $e;
             }
         }
     }
@@ -51,7 +53,19 @@ trait PHPDocElement
                 $this->sinceTags = $phpDoc->getTagsByName('since');
                 $this->deprecatedTags = $phpDoc->getTagsByName('deprecated');
             } catch (Exception $e) {
-                $this->parseError = $e->getMessage();
+                $this->parseError = $e;
+            }
+        }
+    }
+
+    protected function checkIfHasInternalMetaTag(Node $node): void
+    {
+        if ($node->getDocComment() !== null) {
+            try {
+                $phpDoc = DocFactoryProvider::getDocFactory()->create($node->getDocComment()->getText());
+                $this->hasInternalMetaTag = $phpDoc->hasTag('meta');
+            } catch (Exception $e) {
+                $this->parseError = $e;
             }
         }
     }
diff --git a/tests/Model/PHPFunction.php b/tests/Model/PHPFunction.php
index 80a4445d..65672371 100644
--- a/tests/Model/PHPFunction.php
+++ b/tests/Model/PHPFunction.php
@@ -10,7 +10,6 @@ use PhpParser\Node\FunctionLike;
 use PhpParser\Node\Stmt\Function_;
 use ReflectionException;
 use ReflectionFunction;
-use ReflectionParameter;
 use stdClass;
 use StubTests\Parsers\DocFactoryProvider;
 
@@ -21,15 +20,15 @@ class PHPFunction extends BasePHPElement
     /**
      * @var boolean $is_deprecated
      */
-    public $is_deprecated;
+    public bool $is_deprecated;
     /**
      * @var PHPParameter[]
      */
-    public $parameters = [];
+    public array $parameters = [];
     /**
      * @var Type $returnTag
      */
-    public $returnTag;
+    public ?Type $returnTag = null;
 
     /**
      * @param ReflectionFunction $function
@@ -41,7 +40,6 @@ class PHPFunction extends BasePHPElement
             $reflectionFunction = new ReflectionFunction($function);
             $this->name = $reflectionFunction->name;
             $this->is_deprecated = $reflectionFunction->isDeprecated();
-            /**@var ReflectionParameter $parameter */
             foreach ($reflectionFunction->getParameters() as $parameter) {
                 $this->parameters[] = (new PHPParameter())->readObjectFromReflection($parameter);
             }
@@ -66,6 +64,7 @@ class PHPFunction extends BasePHPElement
 
         $this->collectLinks($node);
         $this->collectSinceDeprecatedVersions($node);
+        $this->checkIfHasInternalMetaTag($node);
         $this->checkDeprecationTag($node);
         $this->checkReturnTag($node);
         return $this;
@@ -82,7 +81,7 @@ class PHPFunction extends BasePHPElement
                     $this->is_deprecated = true;
                 }
             } catch (Exception $e) {
-                $this->parseError = $e->getMessage();
+                $this->parseError = $e;
             }
         }
     }
@@ -94,10 +93,10 @@ class PHPFunction extends BasePHPElement
                 $phpDoc = DocFactoryProvider::getDocFactory()->create($node->getDocComment()->getText());
                 $parsedReturnTag = $phpDoc->getTagsByName('return');
                 if (!empty($parsedReturnTag) && $parsedReturnTag[0] instanceof Return_) {
-                    $this->returnTag = $parsedReturnTag[0]->getType() . '';
+                    $this->returnTag = $parsedReturnTag[0]->getType();
                 }
             } catch (Exception $e) {
-                $this->parseError = $e->getMessage();
+                $this->parseError = $e;
             }
         }
     }
diff --git a/tests/Model/PHPInterface.php b/tests/Model/PHPInterface.php
index 6bb4bfc1..8b2f7c16 100644
--- a/tests/Model/PHPInterface.php
+++ b/tests/Model/PHPInterface.php
@@ -5,14 +5,12 @@ namespace StubTests\Model;
 
 use PhpParser\Node\Stmt\Interface_;
 use ReflectionClass;
-use ReflectionClassConstant;
 use ReflectionException;
-use ReflectionMethod;
 use stdClass;
 
 class PHPInterface extends BasePHPClass
 {
-    public $parentInterfaces = [];
+    public array $parentInterfaces = [];
 
     /**
      * @param ReflectionClass $interface
@@ -23,7 +21,6 @@ class PHPInterface extends BasePHPClass
         try {
             $reflectionInterface = new ReflectionClass($interface);
             $this->name = $reflectionInterface->getName();
-            /**@var ReflectionMethod $method */
             foreach ($reflectionInterface->getMethods() as $method) {
                 if ($method->getDeclaringClass()->getName() !== $this->name) {
                     continue;
@@ -31,7 +28,6 @@ class PHPInterface extends BasePHPClass
                 $this->methods[$method->name] = (new PHPMethod())->readObjectFromReflection($method);
             }
             $this->parentInterfaces = $reflectionInterface->getInterfaceNames();
-            /**@var ReflectionClassConstant $constant */
             foreach ($reflectionInterface->getReflectionConstants() as $constant) {
                 if ($constant->getDeclaringClass()->getName() !== $this->name) {
                     continue;
diff --git a/tests/Model/PHPMethod.php b/tests/Model/PHPMethod.php
index 43f04efa..e838ec28 100644
--- a/tests/Model/PHPMethod.php
+++ b/tests/Model/PHPMethod.php
@@ -4,18 +4,18 @@ declare(strict_types=1);
 namespace StubTests\Model;
 
 use PhpParser\Node\Stmt\ClassMethod;
-use ReflectionParameter;
+use ReflectionMethod;
 use stdClass;
 
 class PHPMethod extends PHPFunction
 {
-    public $access;
-    public $is_static;
-    public $is_final;
-    public $parentName;
+    public string $access;
+    public bool $is_static;
+    public bool $is_final;
+    public string $parentName;
 
     /**
-     * @param \ReflectionMethod $method
+     * @param ReflectionMethod $method
      * @return $this
      */
     public function readObjectFromReflection($method)
@@ -23,7 +23,6 @@ class PHPMethod extends PHPFunction
         $this->name = $method->name;
         $this->is_static = $method->isStatic();
         $this->is_final = $method->isFinal();
-        /**@var ReflectionParameter $parameter */
         foreach ($method->getParameters() as $parameter) {
             $this->parameters[] = (new PHPParameter())->readObjectFromReflection($parameter);
         }
@@ -50,6 +49,7 @@ class PHPMethod extends PHPFunction
 
         $this->collectLinks($node);
         $this->collectSinceDeprecatedVersions($node);
+        $this->checkIfHasInternalMetaTag($node);
         $this->checkDeprecationTag($node);
         $this->checkReturnTag($node);
 
diff --git a/tests/Model/PHPParameter.php b/tests/Model/PHPParameter.php
index 71855a5b..79b5a2ea 100644
--- a/tests/Model/PHPParameter.php
+++ b/tests/Model/PHPParameter.php
@@ -4,14 +4,15 @@ declare(strict_types=1);
 namespace StubTests\Model;
 
 use PhpParser\Node\Param;
+use ReflectionNamedType;
 use ReflectionParameter;
 use stdClass;
 
 class PHPParameter extends BasePHPElement
 {
-    public $type = '';
-    public $is_vararg;
-    public $is_passed_by_ref;
+    public string $type = '';
+    public bool $is_vararg;
+    public bool $is_passed_by_ref;
 
     /**
      * @param ReflectionParameter $parameter
@@ -20,8 +21,9 @@ class PHPParameter extends BasePHPElement
     public function readObjectFromReflection($parameter): self
     {
         $this->name = $parameter->name;
-        if (!empty($parameter->getType())) {
-            $this->type = $parameter->getType()->getName();
+        $parameterType = $parameter->getType();
+        if (!empty($parameterType) && $parameterType instanceof ReflectionNamedType) {
+            $this->type = $parameterType->getName();
         }
         $this->is_vararg = $parameter->isVariadic();
         $this->is_passed_by_ref = $parameter->isPassedByReference();
diff --git a/tests/Model/StubsContainer.php b/tests/Model/StubsContainer.php
index ed9bc7ce..43023c88 100644
--- a/tests/Model/StubsContainer.php
+++ b/tests/Model/StubsContainer.php
@@ -3,6 +3,7 @@ declare(strict_types=1);
 
 namespace StubTests\Model;
 
+use Exception;
 use function array_key_exists;
 
 class StubsContainer
@@ -10,19 +11,19 @@ class StubsContainer
     /**
      * @var PHPConst[]
      */
-    private $constants = [];
+    private array $constants = [];
     /**
      * @var PHPFunction[]
      */
-    private $functions = [];
+    private array $functions = [];
     /**
      * @var PHPClass[]
      */
-    private $classes = [];
+    private array $classes = [];
     /**
      * @var PHPInterface[]
      */
-    private $interfaces = [];
+    private array $interfaces = [];
 
     /**
      * @return PHPConst[]
@@ -34,11 +35,12 @@ class StubsContainer
 
     /**
      * @param PHPConst $constant
+     * @throws Exception
      */
     public function addConstant(PHPConst $constant): void
     {
         if (array_key_exists($constant->name, $this->constants)) {
-            throw new \Exception($constant->name . " is already defined in stubs");
+            throw new Exception($constant->name . " is already defined in stubs");
         }
         $this->constants[$constant->name] = $constant;
     }
@@ -61,7 +63,7 @@ class StubsContainer
 
     /**
      * @param string $name
-     * @return PHPClass | null
+     * @return PHPClass|null
      */
     public function getClass(string $name): ?PHPClass
     {
@@ -82,18 +84,19 @@ class StubsContainer
 
     /**
      * @param PHPClass $class
+     * @throws Exception
      */
     public function addClass(PHPClass $class): void
     {
         if (array_key_exists($class->name, $this->classes)) {
-            throw new \Exception($class->name . " is already defined in stubs");
+            throw new Exception($class->name . " is already defined in stubs");
         }
         $this->classes[$class->name] = $class;
     }
 
     /**
      * @param string $name
-     * @return PHPInterface | null
+     * @return PHPInterface|null
      */
     public function getInterface(string $name): ?PHPInterface
     {
@@ -114,11 +117,12 @@ class StubsContainer
 
     /**
      * @param PHPInterface $interface
+     * @throws Exception
      */
     public function addInterface(PHPInterface $interface): void
     {
         if (array_key_exists($interface->name, $this->interfaces)) {
-            throw new \Exception($interface->name . " is already defined in stubs");
+            throw new Exception($interface->name . " is already defined in stubs");
         }
         $this->interfaces[$interface->name] = $interface;
     }
diff --git a/tests/Parsers/DocFactoryProvider.php b/tests/Parsers/DocFactoryProvider.php
index b474bc77..c1e7d4d2 100644
--- a/tests/Parsers/DocFactoryProvider.php
+++ b/tests/Parsers/DocFactoryProvider.php
@@ -7,7 +7,7 @@ use phpDocumentor\Reflection\DocBlockFactory;
 
 class DocFactoryProvider
 {
-    private static $docFactory;
+    private static ?DocBlockFactory $docFactory = null;
 
     public static function getDocFactory(): DocBlockFactory
     {
diff --git a/tests/Parsers/ExpectedFunctionArgumentsInfo.php b/tests/Parsers/ExpectedFunctionArgumentsInfo.php
index dd5bb587..d9eb7a0a 100644
--- a/tests/Parsers/ExpectedFunctionArgumentsInfo.php
+++ b/tests/Parsers/ExpectedFunctionArgumentsInfo.php
@@ -8,16 +8,16 @@ class ExpectedFunctionArgumentsInfo
     /**
      * @var Expr|null
      */
-    private $functionReference;
+    private ?Expr $functionReference;
 
     /**
      * @var Expr[]
      */
-    private $expectedArguments;
+    private array $expectedArguments;
     /**
      * @var int
      */
-    private $index;
+    private int $index;
 
     /**
      * ExpectedFunctionArgumentsInfo constructor.
diff --git a/tests/Parsers/MetaExpectedArgumentsCollector.php b/tests/Parsers/MetaExpectedArgumentsCollector.php
index 772d2190..9bca914f 100644
--- a/tests/Parsers/MetaExpectedArgumentsCollector.php
+++ b/tests/Parsers/MetaExpectedArgumentsCollector.php
@@ -19,11 +19,11 @@ class MetaExpectedArgumentsCollector extends NodeVisitorAbstract
     /**
      * @var ExpectedFunctionArgumentsInfo[]
      */
-    private $expectedArgumentsInfos;
+    private array $expectedArgumentsInfos;
     /**
      * @var String[]
      */
-    private $registeredArgumentsSet;
+    private array $registeredArgumentsSet;
 
     public function __construct()
     {
diff --git a/tests/Parsers/StubParser.php b/tests/Parsers/StubParser.php
index 4ff7a699..fdd3b32e 100644
--- a/tests/Parsers/StubParser.php
+++ b/tests/Parsers/StubParser.php
@@ -21,7 +21,7 @@ use UnexpectedValueException;
 
 class StubParser
 {
-    private static $stubs;
+    private static ?StubsContainer $stubs = null;
 
     public static function getPhpStormStubs(): StubsContainer
     {
@@ -30,7 +30,7 @@ class StubParser
         $coreStubVisitor = new CoreStubASTVisitor(self::$stubs);
         /** @noinspection PhpUnhandledExceptionInspection */
         self::processStubs($visitor, $coreStubVisitor, function ($file) {
-            return true;
+            return $file->getFilename() !== '.phpstorm.meta.php';
         });
         foreach (self::$stubs->getInterfaces() as $interface) {
             $interface->parentInterfaces = $visitor->combineParentInterfaces($interface);
diff --git a/tests/Parsers/Visitors/ASTVisitor.php b/tests/Parsers/Visitors/ASTVisitor.php
index 8c3d7780..f19dd1dc 100644
--- a/tests/Parsers/Visitors/ASTVisitor.php
+++ b/tests/Parsers/Visitors/ASTVisitor.php
@@ -22,8 +22,8 @@ use StubTests\Parsers\Utils;
 
 class ASTVisitor extends NodeVisitorAbstract
 {
-    protected $stubs;
-    protected $isStubCore;
+    protected StubsContainer $stubs;
+    protected bool $isStubCore;
 
     public function __construct(StubsContainer $stubs)
     {
diff --git a/tests/Parsers/Visitors/CoreStubASTVisitor.php b/tests/Parsers/Visitors/CoreStubASTVisitor.php
index eaf0d73f..15a2e038 100644
--- a/tests/Parsers/Visitors/CoreStubASTVisitor.php
+++ b/tests/Parsers/Visitors/CoreStubASTVisitor.php
@@ -1,9 +1,8 @@
 <?php
-
+declare(strict_types=1);
 
 namespace StubTests\Parsers\Visitors;
 
-
 use StubTests\Model\StubsContainer;
 
 class CoreStubASTVisitor extends ASTVisitor
@@ -13,4 +12,4 @@ class CoreStubASTVisitor extends ASTVisitor
         parent::__construct($stubs);
         $this->isStubCore = true;
     }
-}
\ No newline at end of file
+}
diff --git a/tests/Parsers/Visitors/MetaOverrideFunctionsParser.php b/tests/Parsers/Visitors/MetaOverrideFunctionsParser.php
new file mode 100644
index 00000000..30a5858f
--- /dev/null
+++ b/tests/Parsers/Visitors/MetaOverrideFunctionsParser.php
@@ -0,0 +1,53 @@
+<?php
+
+namespace StubTests\Parsers\Visitors;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr;
+use PhpParser\NodeVisitorAbstract;
+use RuntimeException;
+use SplFileInfo;
+use StubTests\Parsers\StubParser;
+
+class MetaOverrideFunctionsParser extends NodeVisitorAbstract
+{
+    private const OVERRIDE_FUNCTION = 'override';
+
+    /**
+     * @var string[]
+     */
+    public array $overridenFunctions;
+
+    public function __construct()
+    {
+        $this->overridenFunctions = [];
+        StubParser::processStubs($this, null, function (SplFileInfo $file) {
+            return $file->getFilename() === '.phpstorm.meta.php';
+        });
+    }
+
+    public function enterNode(Node $node)
+    {
+        if ($node instanceof Node\Expr\FuncCall) {
+            if ((string)$node->name === self::OVERRIDE_FUNCTION) {
+                $args = $node->args;
+                if (count($args) < 2) {
+                    throw new RuntimeException('Expected at least 2 arguments for override call');
+                }
+                $this->overridenFunctions[] = $this->getOverrideFunctionName($args[0]);
+            }
+        }
+    }
+
+    private function getOverrideFunctionName($param)
+    {
+        $paramValue = $param->value;
+        $targetFunction = null;
+        if ($paramValue instanceof Expr\StaticCall) {
+            $targetFunction = $paramValue->class . "::" . $paramValue->name;
+        } else {
+            $targetFunction = (string)$paramValue->name;
+        }
+        return $targetFunction;
+    }
+}
diff --git a/tests/Parsers/Visitors/ParentConnector.php b/tests/Parsers/Visitors/ParentConnector.php
index 417d487c..6e27584f 100644
--- a/tests/Parsers/Visitors/ParentConnector.php
+++ b/tests/Parsers/Visitors/ParentConnector.php
@@ -11,7 +11,10 @@ use PhpParser\NodeVisitorAbstract;
  */
 class ParentConnector extends NodeVisitorAbstract
 {
-    private $stack;
+    /**
+     * @var Node[]
+     */
+    private array $stack;
 
     public function beforeTraverse(array $nodes)
     {
diff --git a/tests/StubsMetaExpectedArgumentsTest.php b/tests/StubsMetaExpectedArgumentsTest.php
index f9c77bb5..53fe51b7 100644
--- a/tests/StubsMetaExpectedArgumentsTest.php
+++ b/tests/StubsMetaExpectedArgumentsTest.php
@@ -7,7 +7,6 @@ use PhpParser\Node\Expr\ClassConstFetch;
 use PhpParser\Node\Expr\ConstFetch;
 use PhpParser\Node\Expr\FuncCall;
 use PhpParser\Node\Expr\StaticCall;
-use PhpParser\Node\Name;
 use PhpParser\Node\Scalar\String_;
 use PHPUnit\Framework\TestCase;
 use StubTests\Model\PHPConst;
@@ -21,14 +20,14 @@ class StubsMetaExpectedArgumentsTest extends TestCase
     /**
      * @var ExpectedFunctionArgumentsInfo[]
      */
-    private static $expectedArguments;
+    private static array $expectedArguments;
     /**
      * @var String[]
      */
-    private static $registeredArgumentsSet;
+    private static array $registeredArgumentsSet;
     private static $functionsFqns;
-    private static $methodsFqns;
-    private static $constantsFqns;
+    private static array $methodsFqns;
+    private static array $constantsFqns;
 
     public static function setUpBeforeClass(): void
     {
diff --git a/tests/StubsMetaInternalTagTest.php b/tests/StubsMetaInternalTagTest.php
new file mode 100644
index 00000000..05b96691
--- /dev/null
+++ b/tests/StubsMetaInternalTagTest.php
@@ -0,0 +1,53 @@
+<?php
+
+namespace StubTests;
+
+use PHPUnit\Framework\TestCase;
+use StubTests\Parsers\Visitors\MetaOverrideFunctionsParser;
+use StubTests\TestData\Providers\PhpStormStubsSingleton;
+
+class StubsMetaInternalTagTest extends TestCase
+{
+    /**
+     * @var array
+     */
+    private static array $overridenFunctionsInMeta;
+
+    public static function setUpBeforeClass()
+    {
+        parent::setUpBeforeClass();
+        self::$overridenFunctionsInMeta = (new MetaOverrideFunctionsParser())->overridenFunctions;
+    }
+
+    public function testFunctionInternalMetaTag(): void
+    {
+        $functions = PhpStormStubsSingleton::getPhpStormStubs()->getFunctions();
+        foreach ($functions as $function) {
+            if ($function->hasInternalMetaTag) {
+                $this->checkInternalMetaInOverride($function->name);
+            }
+        }
+    }
+
+    public function testMethodsInternalMetaTag(): void
+    {
+        foreach (PhpStormStubsSingleton::getPhpStormStubs()->getClasses() as $className => $class) {
+            foreach ($class->methods as $methodName => $method) {
+                if ($method->hasInternalMetaTag) {
+                    $this->checkInternalMetaInOverride($className . "::" . $methodName);
+                } else {
+                    $this->expectNotToPerformAssertions();
+                }
+            }
+        }
+    }
+
+    /**
+     * @param string $elementName
+     */
+    private function checkInternalMetaInOverride(string $elementName): void
+    {
+        self::assertContains($elementName, self::$overridenFunctionsInMeta,
+            "$elementName contains @meta in phpdoc but isn't added to 'override()' functions in meta file");
+    }
+}
diff --git a/tests/TestData/Providers/PhpCoreStubsProvider.php b/tests/TestData/Providers/PhpCoreStubsProvider.php
index 18633e7a..27319325 100644
--- a/tests/TestData/Providers/PhpCoreStubsProvider.php
+++ b/tests/TestData/Providers/PhpCoreStubsProvider.php
@@ -1,14 +1,13 @@
 <?php
-
+declare(strict_types=1);
 
 namespace StubTests\TestData\Providers;
 
-
 use StubTests\Parsers\Utils;
 
 class PhpCoreStubsProvider
 {
-    private static $StubDirectoryMap = [
+    private static array $StubDirectoryMap = [
         'CORE' => [
             'Core',
             'date',
@@ -153,4 +152,4 @@ class PhpCoreStubsProvider
         return Utils::flattenArray($coreStubs, false);
 
     }
-}
\ No newline at end of file
+}
diff --git a/tests/TestData/Providers/PhpStormStubsSingleton.php b/tests/TestData/Providers/PhpStormStubsSingleton.php
index 927a471f..bf266c1e 100644
--- a/tests/TestData/Providers/PhpStormStubsSingleton.php
+++ b/tests/TestData/Providers/PhpStormStubsSingleton.php
@@ -1,4 +1,6 @@
 <?php
+declare(strict_types=1);
+
 namespace StubTests\TestData\Providers;
 
 use StubTests\Model\StubsContainer;
@@ -6,7 +8,7 @@ use StubTests\Parsers\StubParser;
 
 class PhpStormStubsSingleton
 {
-    private static $phpstormStubs;
+    private static ?StubsContainer $phpstormStubs = null;
 
     public static function getPhpStormStubs(): StubsContainer
     {
diff --git a/tests/TestData/Providers/ReflectionTestDataProviders.php b/tests/TestData/Providers/ReflectionTestDataProviders.php
index ad8b28ed..00887160 100644
--- a/tests/TestData/Providers/ReflectionTestDataProviders.php
+++ b/tests/TestData/Providers/ReflectionTestDataProviders.php
@@ -43,7 +43,7 @@ class ReflectionTestDataProviders
 
 class ReflectionStubsSingleton
 {
-    private static $reflectionStubs;
+    private static ?StubsContainer $reflectionStubs = null;
 
     public static function getReflectionStubs(): StubsContainer
     {