diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 44573a0ee..dae21d11e 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -1,5 +1,20 @@
 parameters:
 	ignoreErrors:
+		-
+			message: "#^Property Nelmio\\\\ApiDocBundle\\\\Annotation\\\\Model\\:\\:\\$_required type has no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Annotation/Model.php
+
+		-
+			message: "#^Property Nelmio\\\\ApiDocBundle\\\\Annotation\\\\Security\\:\\:\\$_required type has no value type specified in iterable type array\\.$#"
+			count: 1
+			path: src/Annotation/Security.php
+
+		-
+			message: "#^Only booleans are allowed in an if condition, mixed given\\.$#"
+			count: 1
+			path: src/Describer/ExternalDocDescriber.php
+
 		-
 			message: "#^Method Nelmio\\\\ApiDocBundle\\\\PropertyDescriber\\\\PropertyDescriberInterface\\:\\:describe\\(\\) invoked with 5 parameters, 2\\-3 required\\.$#"
 			count: 1
@@ -50,6 +65,11 @@ parameters:
 			count: 1
 			path: src/Render/Html/HtmlOpenApiRenderer.php
 
+		-
+			message: "#^Parameter \\$twig of method Nelmio\\\\ApiDocBundle\\\\Render\\\\Html\\\\HtmlOpenApiRenderer\\:\\:__construct\\(\\) has invalid type Twig_Environment\\.$#"
+			count: 1
+			path: src/Render/Html/HtmlOpenApiRenderer.php
+
 		-
 			message: "#^Property Nelmio\\\\ApiDocBundle\\\\Render\\\\Html\\\\HtmlOpenApiRenderer\\:\\:\\$twig has unknown class Twig_Environment as its type\\.$#"
 			count: 1
diff --git a/phpstan.dist.neon b/phpstan.dist.neon
index 4d4d69b79..fd35821f1 100644
--- a/phpstan.dist.neon
+++ b/phpstan.dist.neon
@@ -7,7 +7,7 @@ includes:
     - vendor/phpstan/phpstan-strict-rules/rules.neon
 
 parameters:
-    level: 5
+    level: 6
     paths:
         - src
         - tests
@@ -15,6 +15,7 @@ parameters:
         - tests/Functional/Entity/*
         - tests/Functional/EntityExcluded/*
         - tests/Functional/Controller/*
+        - tests/ModelDescriber/Annotations/Fixture/*
     dynamicConstantNames:
         - Symfony\Component\HttpKernel\Kernel::VERSION
         - Symfony\Component\HttpKernel\Kernel::VERSION_ID
@@ -28,3 +29,6 @@ parameters:
     universalObjectCratesClasses:
         - OpenApi\Context
     treatPhpDocTypesAsCertain: false
+    checkGenericClassInNonGenericObjectType: false
+    ignoreErrors:
+        - '#^Property class@anonymous/tests/.* has no type specified.$#'
diff --git a/src/Annotation/Areas.php b/src/Annotation/Areas.php
index 2ac703b4d..50670a044 100644
--- a/src/Annotation/Areas.php
+++ b/src/Annotation/Areas.php
@@ -18,7 +18,7 @@
 final class Areas
 {
     /** @var string[] */
-    private $areas;
+    private array $areas;
 
     /**
      * @param string[]|array{value: string[]} $properties
diff --git a/src/Annotation/Model.php b/src/Annotation/Model.php
index dc0e59502..7f472d238 100644
--- a/src/Annotation/Model.php
+++ b/src/Annotation/Model.php
@@ -33,25 +33,22 @@ final class Model extends Attachable
         Parameter::class,
     ];
 
-    /**
-     * @var string
-     */
-    public $type;
+    public string $type;
 
     /**
-     * @var string[]
+     * @var string[]|null
      */
-    public $groups;
+    public ?array $groups;
 
     /**
-     * @var mixed[]
+     * @var mixed[]|null
      */
-    public $options;
+    public ?array $options;
 
     /**
      * @var array<string, mixed>
      */
-    public $serializationContext;
+    public array $serializationContext;
 
     /**
      * @param mixed[]              $properties
diff --git a/src/Annotation/Security.php b/src/Annotation/Security.php
index 9182f3ecd..ffbf2b6a7 100644
--- a/src/Annotation/Security.php
+++ b/src/Annotation/Security.php
@@ -26,16 +26,17 @@ class Security extends AbstractAnnotation
 
     public static $_required = ['name'];
 
-    /**
-     * @var string
-     */
-    public $name;
+    public ?string $name;
 
     /**
      * @var string[]
      */
-    public $scopes = [];
+    public array $scopes = [];
 
+    /**
+     * @param array<string, mixed> $properties
+     * @param string[]             $scopes
+     */
     public function __construct(
         array $properties = [],
         ?string $name = null,
diff --git a/src/ApiDocGenerator.php b/src/ApiDocGenerator.php
index 4a0da2075..61d805cf3 100644
--- a/src/ApiDocGenerator.php
+++ b/src/ApiDocGenerator.php
@@ -69,17 +69,23 @@ public function __construct($describers, $modelDescribers, ?CacheItemPoolInterfa
         $this->generator = $generator ?? new Generator($this->logger);
     }
 
-    public function setAlternativeNames(array $alternativeNames)
+    /**
+     * @param string[] $alternativeNames
+     */
+    public function setAlternativeNames(array $alternativeNames): void
     {
         $this->alternativeNames = $alternativeNames;
     }
 
-    public function setMediaTypes(array $mediaTypes)
+    /**
+     * @param string[] $mediaTypes
+     */
+    public function setMediaTypes(array $mediaTypes): void
     {
         $this->mediaTypes = $mediaTypes;
     }
 
-    public function setOpenApiVersion(?string $openApiVersion)
+    public function setOpenApiVersion(?string $openApiVersion): void
     {
         $this->openApiVersion = $openApiVersion;
     }
diff --git a/src/Command/DumpCommand.php b/src/Command/DumpCommand.php
index a74821576..900626025 100644
--- a/src/Command/DumpCommand.php
+++ b/src/Command/DumpCommand.php
@@ -20,10 +20,7 @@
 
 class DumpCommand extends Command
 {
-    /**
-     * @var RenderOpenApi
-     */
-    private $renderOpenApi;
+    private RenderOpenApi $renderOpenApi;
 
     /**
      * @var mixed[]
diff --git a/src/Controller/DocumentationController.php b/src/Controller/DocumentationController.php
index a09c6a89b..da47e4ea6 100644
--- a/src/Controller/DocumentationController.php
+++ b/src/Controller/DocumentationController.php
@@ -19,17 +19,14 @@
 
 final class DocumentationController
 {
-    /**
-     * @var RenderOpenApi
-     */
-    private $renderOpenApi;
+    private RenderOpenApi $renderOpenApi;
 
     public function __construct(RenderOpenApi $renderOpenApi)
     {
         $this->renderOpenApi = $renderOpenApi;
     }
 
-    public function __invoke(Request $request, $area = 'default')
+    public function __invoke(Request $request, string $area = 'default'): JsonResponse
     {
         try {
             return JsonResponse::fromJsonString(
diff --git a/src/Controller/SwaggerUiController.php b/src/Controller/SwaggerUiController.php
index 0678b808e..dac206ac4 100644
--- a/src/Controller/SwaggerUiController.php
+++ b/src/Controller/SwaggerUiController.php
@@ -20,15 +20,9 @@
 
 final class SwaggerUiController
 {
-    /**
-     * @var RenderOpenApi
-     */
-    private $renderOpenApi;
+    private RenderOpenApi $renderOpenApi;
 
-    /**
-     * @var string
-     */
-    private $uiRenderer;
+    private string $uiRenderer;
 
     public function __construct(RenderOpenApi $renderOpenApi, string $uiRenderer)
     {
@@ -36,7 +30,7 @@ public function __construct(RenderOpenApi $renderOpenApi, string $uiRenderer)
         $this->uiRenderer = $uiRenderer;
     }
 
-    public function __invoke(Request $request, $area = 'default')
+    public function __invoke(Request $request, string $area = 'default'): Response
     {
         try {
             $response = new Response(
diff --git a/src/Controller/YamlDocumentationController.php b/src/Controller/YamlDocumentationController.php
index 9a320e13a..400eab4ed 100644
--- a/src/Controller/YamlDocumentationController.php
+++ b/src/Controller/YamlDocumentationController.php
@@ -18,17 +18,14 @@
 
 final class YamlDocumentationController
 {
-    /**
-     * @var RenderOpenApi
-     */
-    private $renderOpenApi;
+    private RenderOpenApi $renderOpenApi;
 
     public function __construct(RenderOpenApi $renderOpenApi)
     {
         $this->renderOpenApi = $renderOpenApi;
     }
 
-    public function __invoke(Request $request, $area = 'default')
+    public function __invoke(Request $request, string $area = 'default'): Response
     {
         try {
             $response = new Response(
diff --git a/src/DependencyInjection/NelmioApiDocExtension.php b/src/DependencyInjection/NelmioApiDocExtension.php
index 99555b26a..0a70868a3 100644
--- a/src/DependencyInjection/NelmioApiDocExtension.php
+++ b/src/DependencyInjection/NelmioApiDocExtension.php
@@ -281,6 +281,11 @@ public function load(array $configs, ContainerBuilder $container): void
         }
     }
 
+    /**
+     * @param array<int, mixed> $names
+     *
+     * @return array<string, mixed>
+     */
     private function findNameAliases(array $names, string $area): array
     {
         $nameAliases = array_filter($names, function (array $aliasInfo) use ($area) {
diff --git a/src/Describer/DefaultDescriber.php b/src/Describer/DefaultDescriber.php
index 57a31df04..b69120cf1 100644
--- a/src/Describer/DefaultDescriber.php
+++ b/src/Describer/DefaultDescriber.php
@@ -22,7 +22,7 @@
  */
 final class DefaultDescriber implements DescriberInterface
 {
-    public function describe(OA\OpenApi $api)
+    public function describe(OA\OpenApi $api): void
     {
         // Info
         /** @var OA\Info $info */
diff --git a/src/Describer/DescriberInterface.php b/src/Describer/DescriberInterface.php
index ab92a5c97..bcd7c73ea 100644
--- a/src/Describer/DescriberInterface.php
+++ b/src/Describer/DescriberInterface.php
@@ -15,5 +15,8 @@
 
 interface DescriberInterface
 {
+    /**
+     * @return void
+     */
     public function describe(OpenApi $api);
 }
diff --git a/src/Describer/ExternalDocDescriber.php b/src/Describer/ExternalDocDescriber.php
index 2bfa4f94b..cf827187a 100644
--- a/src/Describer/ExternalDocDescriber.php
+++ b/src/Describer/ExternalDocDescriber.php
@@ -16,12 +16,15 @@
 
 class ExternalDocDescriber implements DescriberInterface
 {
+    /**
+     * @var array<string, mixed>|callable
+     */
     private $externalDoc;
 
-    private $overwrite;
+    private bool $overwrite;
 
     /**
-     * @param array|callable $externalDoc
+     * @param array<string, mixed>|callable $externalDoc
      */
     public function __construct($externalDoc, bool $overwrite = false)
     {
@@ -29,6 +32,9 @@ public function __construct($externalDoc, bool $overwrite = false)
         $this->overwrite = $overwrite;
     }
 
+    /**
+     * @return void
+     */
     public function describe(OA\OpenApi $api)
     {
         $externalDoc = $this->getExternalDoc();
@@ -38,6 +44,9 @@ public function describe(OA\OpenApi $api)
         }
     }
 
+    /**
+     * @return mixed The external doc
+     */
     private function getExternalDoc()
     {
         if (is_callable($this->externalDoc)) {
diff --git a/src/Describer/ModelRegistryAwareInterface.php b/src/Describer/ModelRegistryAwareInterface.php
index 36bdc9e4a..d4dd050af 100644
--- a/src/Describer/ModelRegistryAwareInterface.php
+++ b/src/Describer/ModelRegistryAwareInterface.php
@@ -15,5 +15,8 @@
 
 interface ModelRegistryAwareInterface
 {
+    /**
+     * @return void
+     */
     public function setModelRegistry(ModelRegistry $modelRegistry);
 }
diff --git a/src/Describer/ModelRegistryAwareTrait.php b/src/Describer/ModelRegistryAwareTrait.php
index 3bcdecac3..e88f18a0c 100644
--- a/src/Describer/ModelRegistryAwareTrait.php
+++ b/src/Describer/ModelRegistryAwareTrait.php
@@ -15,11 +15,11 @@
 
 trait ModelRegistryAwareTrait
 {
+    private ModelRegistry $modelRegistry;
+
     /**
-     * @var ModelRegistry
+     * @return void
      */
-    private $modelRegistry;
-
     public function setModelRegistry(ModelRegistry $modelRegistry)
     {
         $this->modelRegistry = $modelRegistry;
diff --git a/src/Describer/OpenApiPhpDescriber.php b/src/Describer/OpenApiPhpDescriber.php
index 66399fa5d..c5da854e8 100644
--- a/src/Describer/OpenApiPhpDescriber.php
+++ b/src/Describer/OpenApiPhpDescriber.php
@@ -31,14 +31,11 @@ final class OpenApiPhpDescriber
 {
     use SetsContextTrait;
 
-    private $routeCollection;
-    private $controllerReflector;
+    private RouteCollection $routeCollection;
+    private ControllerReflector $controllerReflector;
 
-    /**
-     * @var Reader|null
-     */
-    private $annotationReader;
-    private $logger;
+    private ?Reader $annotationReader;
+    private LoggerInterface $logger;
 
     public function __construct(RouteCollection $routeCollection, ControllerReflector $controllerReflector, ?Reader $annotationReader, LoggerInterface $logger, bool $overwrite = false)
     {
@@ -52,7 +49,7 @@ public function __construct(RouteCollection $routeCollection, ControllerReflecto
         $this->logger = $logger;
     }
 
-    public function describe(OA\OpenApi $api)
+    public function describe(OA\OpenApi $api): void
     {
         $classAnnotations = [];
 
@@ -200,6 +197,9 @@ private function getMethodsToParse(): \Generator
         }
     }
 
+    /**
+     * @return string[]
+     */
     private function getSupportedHttpMethods(Route $route): array
     {
         $allMethods = Util::OPERATIONS;
@@ -223,7 +223,7 @@ private function normalizePath(string $path): string
     }
 
     /**
-     * @param \ReflectionClass|\ReflectionMethod $reflection
+     * @param \ReflectionClass<object>|\ReflectionMethod $reflection
      *
      * @return OA\AbstractAnnotation[]
      */
diff --git a/src/Describer/RouteDescriber.php b/src/Describer/RouteDescriber.php
index 00b7ba729..d2a26ac65 100644
--- a/src/Describer/RouteDescriber.php
+++ b/src/Describer/RouteDescriber.php
@@ -20,11 +20,14 @@ final class RouteDescriber implements DescriberInterface, ModelRegistryAwareInte
 {
     use ModelRegistryAwareTrait;
 
-    private $routeCollection;
+    private RouteCollection $routeCollection;
 
-    private $controllerReflector;
+    private ControllerReflector $controllerReflector;
 
-    private $routeDescribers;
+    /**
+     * @var iterable<RouteDescriberInterface>
+     */
+    private iterable $routeDescribers;
 
     /**
      * @param RouteDescriberInterface[]|iterable $routeDescribers
@@ -36,7 +39,7 @@ public function __construct(RouteCollection $routeCollection, ControllerReflecto
         $this->routeDescribers = $routeDescribers;
     }
 
-    public function describe(OA\OpenApi $api)
+    public function describe(OA\OpenApi $api): void
     {
         if (0 === count($this->routeDescribers)) {
             return;
@@ -49,7 +52,7 @@ public function describe(OA\OpenApi $api)
 
             // if able to resolve the controller
             $controller = $route->getDefault('_controller');
-            if ($method = $this->controllerReflector->getReflectionMethod($controller)) {
+            if (null !== $method = $this->controllerReflector->getReflectionMethod($controller)) {
                 // Extract as many information as possible about this route
                 foreach ($this->routeDescribers as $describer) {
                     if ($describer instanceof ModelRegistryAwareInterface) {
diff --git a/src/Exception/UndocumentedArrayItemsException.php b/src/Exception/UndocumentedArrayItemsException.php
index 2ce418741..7e1ee84c2 100644
--- a/src/Exception/UndocumentedArrayItemsException.php
+++ b/src/Exception/UndocumentedArrayItemsException.php
@@ -16,8 +16,8 @@
  */
 class UndocumentedArrayItemsException extends \LogicException
 {
-    private $class;
-    private $path;
+    private ?string $class;
+    private string $path;
 
     public function __construct(?string $class = null, string $path = '')
     {
@@ -33,11 +33,17 @@ public function __construct(?string $class = null, string $path = '')
         parent::__construct(sprintf('Property "%s" is an array, but its items type isn\'t specified. You can specify that by using the type `string[]` for instance or `@OA\Property(type="array", @OA\Items(type="string"))`.', $propertyName));
     }
 
+    /**
+     * @return string|null
+     */
     public function getClass()
     {
         return $this->class;
     }
 
+    /**
+     * @return string
+     */
     public function getPath()
     {
         return $this->path;
diff --git a/src/Form/Extension/DocumentationExtension.php b/src/Form/Extension/DocumentationExtension.php
index ec38b0953..fa6098745 100644
--- a/src/Form/Extension/DocumentationExtension.php
+++ b/src/Form/Extension/DocumentationExtension.php
@@ -32,6 +32,11 @@ public function configureOptions(OptionsResolver $resolver): void
             ->setAllowedTypes('documentation', ['array', 'bool']);
     }
 
+    /**
+     * @deprecated since Symfony 4.2, use getExtendedTypes() instead.
+     *
+     * @return string
+     */
     public function getExtendedType()
     {
         return self::getExtendedTypes()[0];
diff --git a/src/Model/Model.php b/src/Model/Model.php
index b7c796b68..59504e5d5 100644
--- a/src/Model/Model.php
+++ b/src/Model/Model.php
@@ -15,13 +15,22 @@
 
 final class Model
 {
-    private $type;
+    private Type $type;
 
-    private $options;
-    private $serializationContext;
+    /**
+     * @var mixed[]|null
+     */
+    private ?array $options;
+
+    /**
+     * @var mixed[]
+     */
+    private array $serializationContext;
 
     /**
      * @param string[]|null $groups
+     * @param mixed[]|null  $options
+     * @param mixed[]       $serializationContext
      */
     public function __construct(Type $type, ?array $groups = null, ?array $options = null, array $serializationContext = [])
     {
@@ -33,10 +42,7 @@ public function __construct(Type $type, ?array $groups = null, ?array $options =
         }
     }
 
-    /**
-     * @return Type
-     */
-    public function getType()
+    public function getType(): Type
     {
         return $this->type;
     }
@@ -44,7 +50,7 @@ public function getType()
     /**
      * @return string[]|null
      */
-    public function getGroups()
+    public function getGroups(): ?array
     {
         return $this->serializationContext['groups'] ?? null;
     }
@@ -65,7 +71,7 @@ public function getHash(): string
     /**
      * @return mixed[]|null
      */
-    public function getOptions()
+    public function getOptions(): ?array
     {
         return $this->options;
     }
diff --git a/src/Model/ModelRegistry.php b/src/Model/ModelRegistry.php
index 1fadbcaba..3f0defe08 100644
--- a/src/Model/ModelRegistry.php
+++ b/src/Model/ModelRegistry.php
@@ -23,22 +23,41 @@ final class ModelRegistry
 {
     use LoggerAwareTrait;
 
-    private $registeredModelNames = [];
+    /**
+     * @var array<string, Model> List of model names to models
+     */
+    private array $registeredModelNames = [];
 
-    private $alternativeNames = [];
+    /**
+     * @var Model[]
+     */
+    private array $alternativeNames = [];
 
-    private $unregistered = [];
+    /**
+     * @var string[] List of hashes of models that have not been registered yet
+     */
+    private array $unregistered = [];
 
-    private $models = [];
+    /**
+     * @var array<string, Model> List of model hashes to models
+     */
+    private array $models = [];
 
-    private $names = [];
+    /**
+     * @var array<string, string> List of model hashes to model names
+     */
+    private array $names = [];
 
-    private $modelDescribers = [];
+    /**
+     * @var iterable<ModelDescriberInterface>
+     */
+    private iterable $modelDescribers;
 
-    private $api;
+    private OA\OpenApi $api;
 
     /**
      * @param ModelDescriberInterface[]|iterable $modelDescribers
+     * @param array<string, mixed>               $alternativeNames
      *
      * @internal
      */
@@ -109,7 +128,7 @@ public function registerSchemas(): void
             }
         }
 
-        if (!$this->unregistered && $this->alternativeNames) {
+        if ([] === $this->unregistered && [] !== $this->alternativeNames) {
             foreach ($this->alternativeNames as $model) {
                 $this->register($model);
             }
@@ -140,6 +159,9 @@ private function generateModelName(Model $model): string
         return $name;
     }
 
+    /**
+     * @return array<string, mixed>
+     */
     private function modelToArray(Model $model): array
     {
         $getType = function (Type $type) use (&$getType) {
@@ -148,8 +170,8 @@ private function modelToArray(Model $model): array
                 'built_in_type' => $type->getBuiltinType(),
                 'nullable' => $type->isNullable(),
                 'collection' => $type->isCollection(),
-                'collection_key_types' => $type->isCollection() ? array_map($getType, $this->getCollectionKeyTypes($type)) : null,
-                'collection_value_types' => $type->isCollection() ? array_map($getType, $this->getCollectionValueTypes($type)) : null,
+                'collection_key_types' => $type->isCollection() ? array_map($getType, $type->getCollectionKeyTypes()) : null,
+                'collection_value_types' => $type->isCollection() ? array_map($getType, $type->getCollectionValueTypes()) : null,
             ];
         };
 
@@ -191,16 +213,6 @@ private function typeToString(Type $type): string
         }
     }
 
-    private function getCollectionKeyTypes(Type $type): array
-    {
-        return $type->getCollectionKeyTypes();
-    }
-
-    private function getCollectionValueTypes(Type $type): array
-    {
-        return $type->getCollectionValueTypes();
-    }
-
     private function getCollectionValueType(Type $type): ?Type
     {
         return $type->getCollectionValueTypes()[0] ?? null;
diff --git a/src/ModelDescriber/Annotations/AnnotationsReader.php b/src/ModelDescriber/Annotations/AnnotationsReader.php
index d8a299268..df1597263 100644
--- a/src/ModelDescriber/Annotations/AnnotationsReader.php
+++ b/src/ModelDescriber/Annotations/AnnotationsReader.php
@@ -21,10 +21,13 @@
  */
 class AnnotationsReader
 {
-    private $phpDocReader;
-    private $openApiAnnotationsReader;
-    private $symfonyConstraintAnnotationReader;
+    private PropertyPhpDocReader $phpDocReader;
+    private OpenApiAnnotationsReader $openApiAnnotationsReader;
+    private SymfonyConstraintAnnotationReader $symfonyConstraintAnnotationReader;
 
+    /**
+     * @param string[] $mediaTypes
+     */
     public function __construct(
         ?Reader $annotationsReader,
         ModelRegistry $modelRegistry,
@@ -49,11 +52,18 @@ public function updateDefinition(\ReflectionClass $reflectionClass, OA\Schema $s
         );
     }
 
+    /**
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
+     */
     public function getPropertyName($reflection, string $default): string
     {
         return $this->openApiAnnotationsReader->getPropertyName($reflection, $default);
     }
 
+    /**
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
+     * @param string[]|null                         $serializationGroups
+     */
     public function updateProperty($reflection, OA\Property $property, ?array $serializationGroups = null): void
     {
         $this->openApiAnnotationsReader->updateProperty($reflection, $property, $serializationGroups);
diff --git a/src/ModelDescriber/Annotations/OpenApiAnnotationsReader.php b/src/ModelDescriber/Annotations/OpenApiAnnotationsReader.php
index a8153263c..9925d07b6 100644
--- a/src/ModelDescriber/Annotations/OpenApiAnnotationsReader.php
+++ b/src/ModelDescriber/Annotations/OpenApiAnnotationsReader.php
@@ -28,12 +28,12 @@ class OpenApiAnnotationsReader
 {
     use SetsContextTrait;
 
+    private ?Reader $annotationsReader;
+    private ModelRegister $modelRegister;
+
     /**
-     * @var Reader|null
+     * @param string[] $mediaTypes
      */
-    private $annotationsReader;
-    private $modelRegister;
-
     public function __construct(?Reader $annotationsReader, ModelRegistry $modelRegistry, array $mediaTypes)
     {
         $this->annotationsReader = $annotationsReader;
@@ -56,6 +56,9 @@ public function updateSchema(\ReflectionClass $reflectionClass, OA\Schema $schem
         $schema->mergeProperties($oaSchema);
     }
 
+    /**
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
+     */
     public function getPropertyName($reflection, string $default): string
     {
         if (null === $oaProperty = $this->getAnnotation(new Context(), $reflection, OA\Property::class)) {
@@ -65,6 +68,10 @@ public function getPropertyName($reflection, string $default): string
         return Generator::UNDEFINED !== $oaProperty->property ? $oaProperty->property : $default;
     }
 
+    /**
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
+     * @param string[]|null                         $serializationGroups
+     */
     public function updateProperty($reflection, OA\Property $property, ?array $serializationGroups = null): void
     {
         if (null === $oaProperty = $this->getAnnotation($property->_context, $reflection, OA\Property::class)) {
diff --git a/src/ModelDescriber/Annotations/PropertyPhpDocReader.php b/src/ModelDescriber/Annotations/PropertyPhpDocReader.php
index d3b347f7f..dc22111ee 100644
--- a/src/ModelDescriber/Annotations/PropertyPhpDocReader.php
+++ b/src/ModelDescriber/Annotations/PropertyPhpDocReader.php
@@ -15,6 +15,7 @@
 use OpenApi\Generator;
 use phpDocumentor\Reflection\DocBlock\Tags\Var_;
 use phpDocumentor\Reflection\DocBlockFactory;
+use phpDocumentor\Reflection\DocBlockFactoryInterface;
 use phpDocumentor\Reflection\PseudoTypes\IntegerRange;
 use phpDocumentor\Reflection\PseudoTypes\NegativeInteger;
 use phpDocumentor\Reflection\PseudoTypes\PositiveInteger;
@@ -27,7 +28,7 @@
  */
 class PropertyPhpDocReader
 {
-    private $docBlockFactory;
+    private DocBlockFactoryInterface $docBlockFactory;
 
     public function __construct()
     {
@@ -36,6 +37,8 @@ public function __construct()
 
     /**
      * Update the Swagger information with information from the DocBlock comment.
+     *
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
      */
     public function updateProperty($reflection, OA\Property $property): void
     {
@@ -50,7 +53,7 @@ public function updateProperty($reflection, OA\Property $property): void
 
         /** @var Var_ $var */
         foreach ($docBlock->getTagsByName('var') as $var) {
-            if (!$title && method_exists($var, 'getDescription') && null !== $description = $var->getDescription()) {
+            if ('' === $title && method_exists($var, 'getDescription') && null !== $description = $var->getDescription()) {
                 $title = $description->render();
             }
 
@@ -81,10 +84,10 @@ public function updateProperty($reflection, OA\Property $property): void
             }
         }
 
-        if (Generator::UNDEFINED === $property->title && $title) {
+        if (Generator::UNDEFINED === $property->title && '' !== $title) {
             $property->title = $title;
         }
-        if (Generator::UNDEFINED === $property->description && $docBlock->getDescription() && $docBlock->getDescription()->render()) {
+        if (Generator::UNDEFINED === $property->description && '' !== $docBlock->getDescription()->render()) {
             $property->description = $docBlock->getDescription()->render();
         }
         if (Generator::UNDEFINED === $property->minimum && isset($min)) {
diff --git a/src/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php b/src/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
index 78c09f4ed..db69a41b6 100644
--- a/src/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
+++ b/src/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
@@ -52,6 +52,7 @@ public function __construct(?Reader $annotationsReader, bool $useValidationGroup
      * Update the given property and schema with defined Symfony constraints.
      *
      * @param \ReflectionProperty|\ReflectionMethod $reflection
+     * @param string[]|null                         $validationGroups
      */
     public function updateProperty($reflection, OA\Property $property, ?array $validationGroups = null): void
     {
@@ -64,7 +65,11 @@ public function updateProperty($reflection, OA\Property $property, ?array $valid
         }
     }
 
-    private function processPropertyAnnotations($reflection, OA\Property $property, $annotations)
+    /**
+     * @param \ReflectionProperty|\ReflectionMethod $reflection
+     * @param Constraint[]                          $annotations
+     */
+    private function processPropertyAnnotations($reflection, OA\Property $property, array $annotations): void
     {
         foreach ($annotations as $annotation) {
             if ($annotation instanceof Assert\NotBlank || $annotation instanceof Assert\NotNull) {
@@ -138,7 +143,7 @@ private function processPropertyAnnotations($reflection, OA\Property $property,
         }
     }
 
-    public function setSchema($schema): void
+    public function setSchema(OA\Schema $schema): void
     {
         $this->schema = $schema;
     }
@@ -146,7 +151,7 @@ public function setSchema($schema): void
     /**
      * Append the pattern from the constraint to the existing pattern.
      */
-    private function appendPattern(OA\Schema $property, $newPattern): void
+    private function appendPattern(OA\Schema $property, ?string $newPattern): void
     {
         if (null === $newPattern) {
             return;
@@ -179,6 +184,9 @@ private function applyEnumFromChoiceConstraint(OA\Schema $property, Assert\Choic
 
     /**
      * @param \ReflectionProperty|\ReflectionMethod $reflection
+     * @param string[]|null                         $validationGroups
+     *
+     * @return iterable<Constraint>
      */
     private function getAnnotations(Context $parentContext, $reflection, ?array $validationGroups): iterable
     {
@@ -200,10 +208,12 @@ private function getAnnotations(Context $parentContext, $reflection, ?array $val
 
     /**
      * @param \ReflectionProperty|\ReflectionMethod $reflection
+     *
+     * @return \Traversable<Constraint>
      */
     private function locateAnnotations($reflection): \Traversable
     {
-        if (\PHP_VERSION_ID >= 80000 && class_exists(Constraint::class)) {
+        if (\PHP_VERSION_ID >= 80000) {
             foreach ($reflection->getAttributes(Constraint::class, \ReflectionAttribute::IS_INSTANCEOF) as $attribute) {
                 yield $attribute->newInstance();
             }
@@ -225,6 +235,8 @@ private function locateAnnotations($reflection): \Traversable
      * and constraints without any `groups` passed to them would be in that same
      * default group. So even with a null $validationGroups passed here there still
      * has to be a check on the default group.
+     *
+     * @param string[]|null $validationGroups
      */
     private function isConstraintInGroup(Constraint $annotation, ?array $validationGroups): bool
     {
diff --git a/src/ModelDescriber/Annotations/UpdateClassDefinitionResult.php b/src/ModelDescriber/Annotations/UpdateClassDefinitionResult.php
index 3a3945c3e..1cafbd4f2 100644
--- a/src/ModelDescriber/Annotations/UpdateClassDefinitionResult.php
+++ b/src/ModelDescriber/Annotations/UpdateClassDefinitionResult.php
@@ -20,14 +20,14 @@
 final class UpdateClassDefinitionResult
 {
     /**
-     * Whether or not the model describer shoudl continue reading class properties
+     * Whether the model describer should continue reading class properties
      * after updating the open api schema from an `OA\Schema` definition.
      *
-     * Users may maually define a `type` or `ref` on a schema, and if that's the case
+     * Users may manually define a `type` or `ref` on a schema, and if that's the case
      * model describers should _probably_ not describe any additional properties or try
      * to merge in properties.
      */
-    private $shouldDescribeModelProperties;
+    private bool $shouldDescribeModelProperties;
 
     public function __construct(bool $shouldDescribeModelProperties)
     {
diff --git a/src/ModelDescriber/BazingaHateoasModelDescriber.php b/src/ModelDescriber/BazingaHateoasModelDescriber.php
index c1cfa0b3c..ef7803780 100644
--- a/src/ModelDescriber/BazingaHateoasModelDescriber.php
+++ b/src/ModelDescriber/BazingaHateoasModelDescriber.php
@@ -26,8 +26,8 @@ class BazingaHateoasModelDescriber implements ModelDescriberInterface, ModelRegi
 {
     use ModelRegistryAwareTrait;
 
-    private $factory;
-    private $JMSModelDescriber;
+    private MetadataFactoryInterface $factory;
+    private JMSModelDescriber $JMSModelDescriber;
 
     public function __construct(MetadataFactoryInterface $factory, JMSModelDescriber $JMSModelDescriber)
     {
@@ -45,18 +45,14 @@ public function describe(Model $model, OA\Schema $schema): void
     {
         $this->JMSModelDescriber->describe($model, $schema);
 
-        /**
-         * @var ClassMetadata
-         */
         $metadata = $this->getHateoasMetadata($model);
-        if (null === $metadata) {
+        if (!$metadata instanceof ClassMetadata) {
             return;
         }
 
         $schema->type = 'object';
         $context = $this->JMSModelDescriber->getSerializationContext($model);
 
-        /** @var Relation $relation */
         foreach ($metadata->getRelations() as $relation) {
             if (null === $relation->getEmbedded() && null === $relation->getHref()) {
                 continue;
@@ -89,14 +85,10 @@ public function describe(Model $model, OA\Schema $schema): void
         }
     }
 
-    private function getHateoasMetadata(Model $model)
+    private function getHateoasMetadata(Model $model): ?object
     {
-        $className = $model->getType()->getClassName();
-
         try {
-            if ($metadata = $this->factory->getMetadataForClass($className)) {
-                return $metadata;
-            }
+            return $this->factory->getMetadataForClass($model->getType()->getClassName());
         } catch (\ReflectionException $e) {
         }
 
@@ -105,7 +97,8 @@ private function getHateoasMetadata(Model $model)
 
     public function supports(Model $model): bool
     {
-        return $this->JMSModelDescriber->supports($model) || null !== $this->getHateoasMetadata($model);
+        return $this->JMSModelDescriber->supports($model)
+            || $this->getHateoasMetadata($model) instanceof ClassMetadata;
     }
 
     private function setAttributeProperties(Relation $relation, OA\Property $subProperty): void
diff --git a/src/ModelDescriber/FallbackObjectModelDescriber.php b/src/ModelDescriber/FallbackObjectModelDescriber.php
index 19ff1fc27..696bd15fc 100644
--- a/src/ModelDescriber/FallbackObjectModelDescriber.php
+++ b/src/ModelDescriber/FallbackObjectModelDescriber.php
@@ -17,6 +17,9 @@
 
 class FallbackObjectModelDescriber implements ModelDescriberInterface
 {
+    /**
+     * @return void
+     */
     public function describe(Model $model, OA\Schema $schema)
     {
     }
diff --git a/src/ModelDescriber/FormModelDescriber.php b/src/ModelDescriber/FormModelDescriber.php
index 998ab3eb5..5ad00753b 100644
--- a/src/ModelDescriber/FormModelDescriber.php
+++ b/src/ModelDescriber/FormModelDescriber.php
@@ -39,16 +39,19 @@ final class FormModelDescriber implements ModelDescriberInterface, ModelRegistry
     use ModelRegistryAwareTrait;
     use SetsContextTrait;
 
-    private $formFactory;
+    private ?FormFactoryInterface $formFactory;
+    private ?Reader $doctrineReader;
 
     /**
-     * @var Reader|null
+     * @var string[]
      */
-    private $doctrineReader;
-    private $mediaTypes;
-    private $useValidationGroups;
-    private $isFormCsrfExtensionEnabled;
+    private array $mediaTypes;
+    private bool $useValidationGroups;
+    private bool $isFormCsrfExtensionEnabled;
 
+    /**
+     * @param string[]|null $mediaTypes
+     */
     public function __construct(
         ?FormFactoryInterface $formFactory = null,
         ?Reader $reader = null,
@@ -69,7 +72,7 @@ public function __construct(
         $this->isFormCsrfExtensionEnabled = $isFormCsrfExtensionEnabled;
     }
 
-    public function describe(Model $model, OA\Schema $schema)
+    public function describe(Model $model, OA\Schema $schema): void
     {
         if (method_exists(AbstractType::class, 'setDefaultOptions')) {
             throw new \LogicException('symfony/form < 3.0 is not supported, please upgrade to an higher version to use a form as a model.');
@@ -107,7 +110,7 @@ public function supports(Model $model): bool
         return is_a($model->getType()->getClassName(), FormTypeInterface::class, true);
     }
 
-    private function parseForm(OA\Schema $schema, FormInterface $form)
+    private function parseForm(OA\Schema $schema, FormInterface $form): void
     {
         foreach ($form as $name => $child) {
             $config = $child->getConfig();
@@ -157,10 +160,8 @@ private function parseForm(OA\Schema $schema, FormInterface $form)
 
     /**
      * Finds and sets the schema type on $property based on $config info.
-     *
-     * Returns true if a native OpenAPi type was found, false otherwise
      */
-    private function findFormType(FormConfigInterface $config, OA\Schema $property)
+    private function findFormType(FormConfigInterface $config, OA\Schema $property): void
     {
         $type = $config->getType();
 
@@ -305,6 +306,8 @@ private function findFormType(FormConfigInterface $config, OA\Schema $property)
     }
 
     /**
+     * @param mixed[] $array
+     *
      * @return bool true if $array contains only numbers, false otherwise
      */
     private function isNumbersArray(array $array): bool
@@ -319,6 +322,8 @@ private function isNumbersArray(array $array): bool
     }
 
     /**
+     * @param mixed[] $array
+     *
      * @return bool true if $array contains only booleans, false otherwise
      */
     private function isBooleansArray(array $array): bool
@@ -332,10 +337,7 @@ private function isBooleansArray(array $array): bool
         return true;
     }
 
-    /**
-     * @return ResolvedFormTypeInterface|null
-     */
-    private function getBuiltinFormType(ResolvedFormTypeInterface $type)
+    private function getBuiltinFormType(ResolvedFormTypeInterface $type): ?ResolvedFormTypeInterface
     {
         do {
             $class = get_class($type->getInnerType());
diff --git a/src/ModelDescriber/JMSModelDescriber.php b/src/ModelDescriber/JMSModelDescriber.php
index 3d38eebae..a5a9ea66c 100644
--- a/src/ModelDescriber/JMSModelDescriber.php
+++ b/src/ModelDescriber/JMSModelDescriber.php
@@ -36,33 +36,39 @@ class JMSModelDescriber implements ModelDescriberInterface, ModelRegistryAwareIn
     use ModelRegistryAwareTrait;
     use ApplyOpenApiDiscriminatorTrait;
 
-    private $factory;
+    private MetadataFactoryInterface $factory;
 
-    private $contextFactory;
+    private ?SerializationContextFactoryInterface $contextFactory;
 
-    private $namingStrategy;
+    private ?PropertyNamingStrategyInterface $namingStrategy;
+
+    private ?Reader $doctrineReader;
 
     /**
-     * @var Reader|null
+     * @var array<string, Context>
      */
-    private $doctrineReader;
-
-    private $contexts = [];
+    private array $contexts = [];
 
-    private $metadataStacks = [];
-
-    private $mediaTypes;
+    /**
+     * @var array<string, \SplStack>
+     */
+    private array $metadataStacks = [];
 
     /**
-     * @var array
+     * @var string[]
      */
-    private $propertyTypeUseGroupsCache = [];
+    private array $mediaTypes;
 
     /**
-     * @var bool
+     * @var array<string, bool|null>
      */
-    private $useValidationGroups;
+    private array $propertyTypeUseGroupsCache = [];
+
+    private bool $useValidationGroups;
 
+    /**
+     * @param string[] $mediaTypes
+     */
     public function __construct(
         MetadataFactoryInterface $factory,
         ?Reader $reader,
@@ -79,6 +85,9 @@ public function __construct(
         $this->contextFactory = $contextFactory;
     }
 
+    /**
+     * @return void
+     */
     public function describe(Model $model, OA\Schema $schema)
     {
         $className = $model->getType()->getClassName();
@@ -200,7 +209,7 @@ public function describe(Model $model, OA\Schema $schema)
     /**
      * @internal
      */
-    public function getSerializationContext(Model $model): SerializationContext
+    public function getSerializationContext(Model $model): Context
     {
         if (isset($this->contexts[$model->getHash()])) {
             $context = $this->contexts[$model->getHash()];
@@ -214,7 +223,9 @@ public function getSerializationContext(Model $model): SerializationContext
                 $stack->unshift($metadataCopy);
             }
         } else {
-            $context = $this->contextFactory ? $this->contextFactory->createSerializationContext() : SerializationContext::create();
+            $context = null !== $this->contextFactory
+                ? $this->contextFactory->createSerializationContext()
+                : SerializationContext::create();
 
             if (null !== $model->getGroups()) {
                 $context->addExclusionStrategy(new GroupsExclusionStrategy($model->getGroups()));
@@ -224,7 +235,12 @@ public function getSerializationContext(Model $model): SerializationContext
         return $context;
     }
 
-    private function computeGroups(Context $context, ?array $type = null)
+    /**
+     * @param mixed[]|null $type
+     *
+     * @return string[]|null
+     */
+    private function computeGroups(Context $context, ?array $type = null): ?array
     {
         if (null === $type || true !== $this->propertyTypeUsesGroups($type)) {
             return null;
@@ -248,7 +264,7 @@ public function supports(Model $model): bool
         $className = $model->getType()->getClassName();
 
         try {
-            if ($this->factory->getMetadataForClass($className)) {
+            if (null !== $this->factory->getMetadataForClass($className)) {
                 return true;
             }
         } catch (\ReflectionException $e) {
@@ -259,8 +275,10 @@ public function supports(Model $model): bool
 
     /**
      * @internal
+     *
+     * @param mixed[] $type
      */
-    public function describeItem(array $type, OA\Schema $property, Context $context)
+    public function describeItem(array $type, OA\Schema $property, Context $context): void
     {
         $nestedTypeInfo = $this->getNestedTypeInArray($type);
         if (null !== $nestedTypeInfo) {
@@ -329,7 +347,12 @@ public function describeItem(array $type, OA\Schema $property, Context $context)
         }
     }
 
-    private function getNestedTypeInArray(array $type)
+    /**
+     * @param mixed[] $type
+     *
+     * @return array{0: mixed, 1: bool}|null
+     */
+    private function getNestedTypeInArray(array $type): ?array
     {
         if ('array' !== $type['name'] && 'ArrayCollection' !== $type['name']) {
             return null;
@@ -347,9 +370,9 @@ private function getNestedTypeInArray(array $type)
     }
 
     /**
-     * @return bool|null
+     * @param mixed[] $type
      */
-    private function propertyTypeUsesGroups(array $type)
+    private function propertyTypeUsesGroups(array $type): ?bool
     {
         if (array_key_exists($type['name'], $this->propertyTypeUseGroupsCache)) {
             return $this->propertyTypeUseGroupsCache[$type['name']];
@@ -359,7 +382,7 @@ private function propertyTypeUsesGroups(array $type)
             $metadata = $this->factory->getMetadataForClass($type['name']);
 
             foreach ($metadata->propertyMetadata as $item) {
-                if (null !== $item->groups && $item->groups != [GroupsExclusionStrategy::DEFAULT_GROUP]) {
+                if (isset($item->groups) && $item->groups != [GroupsExclusionStrategy::DEFAULT_GROUP]) {
                     $this->propertyTypeUseGroupsCache[$type['name']] = true;
 
                     return true;
diff --git a/src/ModelDescriber/ModelDescriberInterface.php b/src/ModelDescriber/ModelDescriberInterface.php
index 56c2d808d..4d6415332 100644
--- a/src/ModelDescriber/ModelDescriberInterface.php
+++ b/src/ModelDescriber/ModelDescriberInterface.php
@@ -16,6 +16,9 @@
 
 interface ModelDescriberInterface
 {
+    /**
+     * @return void
+     */
     public function describe(Model $model, Schema $schema);
 
     public function supports(Model $model): bool;
diff --git a/src/ModelDescriber/ObjectModelDescriber.php b/src/ModelDescriber/ObjectModelDescriber.php
index 5a93158fa..eac0370eb 100644
--- a/src/ModelDescriber/ObjectModelDescriber.php
+++ b/src/ModelDescriber/ObjectModelDescriber.php
@@ -49,6 +49,7 @@ class ObjectModelDescriber implements ModelDescriberInterface, ModelRegistryAwar
     /**
      * @param PropertyDescriberInterface|PropertyDescriberInterface[]      $propertyDescribers
      * @param (NameConverterInterface&AdvancedNameConverterInterface)|null $nameConverter
+     * @param string[]                                                     $mediaTypes
      */
     public function __construct(
         PropertyInfoExtractorInterface $propertyInfo,
@@ -218,7 +219,7 @@ private function camelize(string $string): string
     /**
      * @param Type[] $types
      */
-    private function describeProperty(array $types, Model $model, OA\Schema $property, string $propertyName, OA\Schema $schema)
+    private function describeProperty(array $types, Model $model, OA\Schema $property, string $propertyName, OA\Schema $schema): void
     {
         $propertyDescribers = is_iterable($this->propertyDescriber) ? $this->propertyDescriber : [$this->propertyDescriber];
 
diff --git a/src/OpenApiPhp/ModelRegister.php b/src/OpenApiPhp/ModelRegister.php
index 7de7a46c9..de20ee6bb 100644
--- a/src/OpenApiPhp/ModelRegister.php
+++ b/src/OpenApiPhp/ModelRegister.php
@@ -26,19 +26,24 @@
  */
 final class ModelRegister
 {
-    /** @var ModelRegistry */
-    private $modelRegistry;
+    private ModelRegistry $modelRegistry;
 
     /** @var string[] */
-    private $mediaTypes;
+    private array $mediaTypes;
 
+    /**
+     * @param string[] $mediaTypes
+     */
     public function __construct(ModelRegistry $modelRegistry, array $mediaTypes)
     {
         $this->modelRegistry = $modelRegistry;
         $this->mediaTypes = $mediaTypes;
     }
 
-    public function __invoke(Analysis $analysis, ?array $parentGroups = null)
+    /**
+     * @param string[]|null $parentGroups
+     */
+    public function __invoke(Analysis $analysis, ?array $parentGroups = null): void
     {
         foreach ($analysis->annotations as $annotation) {
             // @Model using the ref field
@@ -92,11 +97,6 @@ public function __invoke(Analysis $analysis, ?array $parentGroups = null)
                 $annotationClass = OA\Schema::class;
             }
 
-            if (!is_string($model->type)) {
-                // Ignore invalid annotations, they are validated later
-                continue;
-            }
-
             $annotation->merge([new $annotationClass([
                 'ref' => $this->modelRegistry->register(new Model($this->createType($model->type), $this->getGroups($model, $parentGroups), $model->options, $model->serializationContext)),
             ])]);
@@ -106,6 +106,11 @@ public function __invoke(Analysis $analysis, ?array $parentGroups = null)
         }
     }
 
+    /**
+     * @param string[]|null $parentGroups
+     *
+     * @return string[]|null
+     */
     private function getGroups(ModelAnnotation $model, ?array $parentGroups = null): ?array
     {
         if (null === $model->groups) {
@@ -152,12 +157,15 @@ private function getModel(OA\AbstractAnnotation $annotation): ?ModelAnnotation
         return null;
     }
 
+    /**
+     * @param mixed[] $properties
+     */
     private function createContentForMediaType(
         string $type,
         array $properties,
         OA\AbstractAnnotation $annotation,
         Analysis $analysis
-    ) {
+    ): void {
         switch ($type) {
             case 'json':
                 $modelAnnotation = new OA\JsonContent($properties);
diff --git a/src/OpenApiPhp/Util.php b/src/OpenApiPhp/Util.php
index fa3f18e2c..9c967b731 100644
--- a/src/OpenApiPhp/Util.php
+++ b/src/OpenApiPhp/Util.php
@@ -54,7 +54,7 @@ final class Util
     /**
      * All http method verbs as known by swagger.
      *
-     * @var array
+     * @var string[]
      */
     public const OPERATIONS = ['get', 'post', 'put', 'patch', 'delete', 'options', 'head', 'trace'];
 
@@ -64,10 +64,8 @@ final class Util
      *
      * @see OA\OpenApi::$paths
      * @see OA\PathItem::path
-     *
-     * @param string $path
      */
-    public static function getPath(OA\OpenApi $api, $path): OA\PathItem
+    public static function getPath(OA\OpenApi $api, string $path): OA\PathItem
     {
         return self::getIndexedCollectionItem($api, OA\PathItem::class, $path);
     }
@@ -76,12 +74,10 @@ public static function getPath(OA\OpenApi $api, $path): OA\PathItem
      * Return an existing Schema object from $api->components->schemas[] having its member schema set to $schema.
      * Create, add to $api->components->schemas[] and return this new Schema object and set the property if none found.
      *
-     * @param string $schema
-     *
      * @see OA\Schema::$schema
      * @see OA\Components::$schemas
      */
-    public static function getSchema(OA\OpenApi $api, $schema): OA\Schema
+    public static function getSchema(OA\OpenApi $api, string $schema): OA\Schema
     {
         if (!$api->components instanceof OA\Components) {
             $api->components = new OA\Components(['_context' => self::createWeakContext($api->_context)]);
@@ -99,10 +95,8 @@ public static function getSchema(OA\OpenApi $api, $schema): OA\Schema
      *
      * @see OA\Schema::$properties
      * @see OA\Property::$property
-     *
-     * @param string $property
      */
-    public static function getProperty(OA\Schema $schema, $property): OA\Property
+    public static function getProperty(OA\Schema $schema, string $property): OA\Property
     {
         return self::getIndexedCollectionItem($schema, OA\Property::class, $property);
     }
@@ -111,17 +105,15 @@ public static function getProperty(OA\Schema $schema, $property): OA\Property
      * Return an existing Operation from $path->{$method}
      * or create, set $path->{$method} and return this new Operation object.
      *
-     * @see OA\PathItem::$get
      * @see OA\PathItem::$post
      * @see OA\PathItem::$put
      * @see OA\PathItem::$patch
      * @see OA\PathItem::$delete
      * @see OA\PathItem::$options
      * @see OA\PathItem::$head
-     *
-     * @param string $method
+     * @see OA\PathItem::$get
      */
-    public static function getOperation(OA\PathItem $path, $method): OA\Operation
+    public static function getOperation(OA\PathItem $path, string $method): OA\Operation
     {
         $class = array_keys($path::$_nested, \strtolower($method), true)[0];
 
@@ -160,13 +152,14 @@ public static function getOperationParameter(OA\Operation $operation, $name, $in
      *
      * @template T of OA\AbstractAnnotation
      *
-     * @param class-string<T> $class
+     * @param class-string<T>      $class
+     * @param array<string, mixed> $properties
      *
      * @return T
      *
      * @see OA\AbstractAnnotation::$_nested
      */
-    public static function getChild(OA\AbstractAnnotation $parent, $class, array $properties = []): OA\AbstractAnnotation
+    public static function getChild(OA\AbstractAnnotation $parent, string $class, array $properties = []): OA\AbstractAnnotation
     {
         $nested = $parent::$_nested;
         $property = $nested[$class];
@@ -190,13 +183,14 @@ public static function getChild(OA\AbstractAnnotation $parent, $class, array $pr
      *
      * @template T of OA\AbstractAnnotation
      *
-     * @param class-string<T> $class
+     * @param class-string<T>      $class
+     * @param array<string, mixed> $properties
      *
      * @return T
      *
      * @see OA\AbstractAnnotation::$_nested
      */
-    public static function getCollectionItem(OA\AbstractAnnotation $parent, $class, array $properties = []): OA\AbstractAnnotation
+    public static function getCollectionItem(OA\AbstractAnnotation $parent, string $class, array $properties = []): OA\AbstractAnnotation
     {
         $key = null;
         $nested = $parent::$_nested;
@@ -228,12 +222,13 @@ public static function getCollectionItem(OA\AbstractAnnotation $parent, $class,
      * @template T of OA\AbstractAnnotation
      *
      * @param class-string<T> $class
+     * @param mixed           $value The value to set
      *
      * @return T
      *
      * @see OA\AbstractAnnotation::$_nested
      */
-    public static function getIndexedCollectionItem(OA\AbstractAnnotation $parent, $class, $value): OA\AbstractAnnotation
+    public static function getIndexedCollectionItem(OA\AbstractAnnotation $parent, string $class, $value): OA\AbstractAnnotation
     {
         $nested = $parent::$_nested;
         [$collection, $property] = $nested[$class];
@@ -255,6 +250,9 @@ public static function getIndexedCollectionItem(OA\AbstractAnnotation $parent, $
      * Search for an Annotation within $collection that has all members set
      * to the respective values in the associative array $properties.
      *
+     * @param mixed[] $properties
+     * @param mixed[] $collection
+     *
      * @return int|string|null
      */
     public static function searchCollectionItem(array $collection, array $properties)
@@ -275,11 +273,12 @@ public static function searchCollectionItem(array $collection, array $properties
     /**
      * Search for an Annotation within the $collection that has its member $index set to $value.
      *
-     * @param string $member
+     * @param mixed[] $collection
+     * @param mixed   $value      The value to search for
      *
      * @return false|int|string
      */
-    public static function searchIndexedCollectionItem(array $collection, $member, $value)
+    public static function searchIndexedCollectionItem(array $collection, string $member, $value)
     {
         return array_search($value, array_column($collection, $member), true);
     }
@@ -288,10 +287,12 @@ public static function searchIndexedCollectionItem(array $collection, $member, $
      * Create a new Object of $class with members $properties within $parent->{$collection}[]
      * and return the created index.
      *
-     * @param string $collection
-     * @param string $class
+     * @template T of OA\AbstractAnnotation
+     *
+     * @param class-string<T>      $class
+     * @param array<string, mixed> $properties
      */
-    public static function createCollectionItem(OA\AbstractAnnotation $parent, $collection, $class, array $properties = []): int
+    public static function createCollectionItem(OA\AbstractAnnotation $parent, string $collection, string $class, array $properties = []): int
     {
         if (Generator::UNDEFINED === $parent->{$collection}) {
             $parent->{$collection} = [];
@@ -308,13 +309,14 @@ public static function createCollectionItem(OA\AbstractAnnotation $parent, $coll
      *
      * @template T of OA\AbstractAnnotation
      *
-     * @param class-string<T> $class
+     * @param class-string<T>      $class
+     * @param array<string, mixed> $properties
      *
      * @return T
      *
      * @throws \InvalidArgumentException at an attempt to pass in properties that are found in $parent::$_nested
      */
-    public static function createChild(OA\AbstractAnnotation $parent, $class, array $properties = []): OA\AbstractAnnotation
+    public static function createChild(OA\AbstractAnnotation $parent, string $class, array $properties = []): OA\AbstractAnnotation
     {
         $nesting = self::getNestingIndexes($class);
 
@@ -330,6 +332,8 @@ public static function createChild(OA\AbstractAnnotation $parent, $class, array
     /**
      * Create a new Context with members $properties and parent context $parent.
      *
+     * @param array<string, mixed> $properties
+     *
      * @see Context
      */
     public static function createContext(array $properties = [], ?Context $parent = null): Context
@@ -340,6 +344,8 @@ public static function createContext(array $properties = [], ?Context $parent =
     /**
      * Create a new Context by copying the properties of the parent, but without a reference to the parent.
      *
+     * @param array<string, mixed> $additionalProperties
+     *
      * @see Context
      */
     public static function createWeakContext(?Context $parent = null, array $additionalProperties = []): Context
@@ -375,9 +381,9 @@ public static function createWeakContext(?Context $parent = null, array $additio
      * The main purpose is to create a Swagger Object from array config values
      * in the structure of a json serialized Swagger object.
      *
-     * @param array|\ArrayObject|OA\AbstractAnnotation $from
+     * @param array<mixed>|\ArrayObject|OA\AbstractAnnotation $from
      */
-    public static function merge(OA\AbstractAnnotation $annotation, $from, bool $overwrite = false)
+    public static function merge(OA\AbstractAnnotation $annotation, $from, bool $overwrite = false): void
     {
         if (\is_array($from)) {
             self::mergeFromArray($annotation, $from, $overwrite);
@@ -408,7 +414,10 @@ public static function getSchemaPropertyName(OA\Schema $schema, OA\Schema $prope
         return null;
     }
 
-    private static function mergeFromArray(OA\AbstractAnnotation $annotation, array $properties, bool $overwrite)
+    /**
+     * @param array<string, mixed> $properties
+     */
+    private static function mergeFromArray(OA\AbstractAnnotation $annotation, array $properties, bool $overwrite): void
     {
         $done = [];
 
@@ -428,7 +437,7 @@ private static function mergeFromArray(OA\AbstractAnnotation $annotation, array
             } elseif (\array_key_exists($propertyName[0], $properties)) {
                 $collection = $propertyName[0];
                 $property = $propertyName[1] ?? null;
-                self::mergeCollection($annotation, $className, $collection, $property, $properties[$collection], $overwrite);
+                self::mergeCollection($annotation, $className, $property, $properties[$collection], $overwrite);
                 $done[] = $collection;
             }
         }
@@ -463,12 +472,24 @@ private static function mergeFromArray(OA\AbstractAnnotation $annotation, array
         }
     }
 
-    private static function mergeChild(OA\AbstractAnnotation $annotation, $className, $value, bool $overwrite)
+    /**
+     * @template T of OA\AbstractAnnotation
+     *
+     * @param class-string<T> $className
+     * @param mixed           $value     The value of the property
+     */
+    private static function mergeChild(OA\AbstractAnnotation $annotation, string $className, $value, bool $overwrite): void
     {
         self::merge(self::getChild($annotation, $className), $value, $overwrite);
     }
 
-    private static function mergeCollection(OA\AbstractAnnotation $annotation, $className, $collection, $property, $items, bool $overwrite)
+    /**
+     * @template T of OA\AbstractAnnotation
+     *
+     * @param class-string<T>           $className
+     * @param array<mixed>|\ArrayObject $items
+     */
+    private static function mergeCollection(OA\AbstractAnnotation $annotation, string $className, ?string $property, $items, bool $overwrite): void
     {
         if (null !== $property) {
             foreach ($items as $prop => $value) {
@@ -492,7 +513,12 @@ private static function mergeCollection(OA\AbstractAnnotation $annotation, $clas
         }
     }
 
-    private static function mergeTyped(OA\AbstractAnnotation $annotation, $propertyName, $type, array $properties, array $defaults, bool $overwrite)
+    /**
+     * @param array<string, mixed> $properties
+     * @param array<string, mixed> $defaults
+     * @param string|array<string> $type
+     */
+    private static function mergeTyped(OA\AbstractAnnotation $annotation, string $propertyName, $type, array $properties, array $defaults, bool $overwrite): void
     {
         if (\is_string($type) && 0 === strpos($type, '[')) {
             $innerType = substr($type, 1, -1);
@@ -521,14 +547,25 @@ private static function mergeTyped(OA\AbstractAnnotation $annotation, $propertyN
         }
     }
 
-    private static function mergeProperty(OA\AbstractAnnotation $annotation, $propertyName, $value, $default, bool $overwrite)
+    /**
+     * @param mixed $value   The new value of the property
+     * @param mixed $default The default value of the property
+     */
+    private static function mergeProperty(OA\AbstractAnnotation $annotation, string $propertyName, $value, $default, bool $overwrite): void
     {
         if (true === $overwrite || $default === $annotation->{$propertyName}) {
             $annotation->{$propertyName} = $value;
         }
     }
 
-    private static function getNestingIndexes($class): array
+    /**
+     * @template T of OA\AbstractAnnotation
+     *
+     * @param class-string<T> $class
+     *
+     * @return array<int, string>
+     */
+    private static function getNestingIndexes(string $class): array
     {
         return array_values(array_map(
             function ($value) {
@@ -540,6 +577,8 @@ function ($value) {
 
     /**
      * Helper method to modify an annotation value only if its value has not yet been set.
+     *
+     * @param mixed $value The new value to set
      */
     public static function modifyAnnotationValue(OA\AbstractAnnotation $parameter, string $property, $value): void
     {
diff --git a/src/Processor/MapQueryStringProcessor.php b/src/Processor/MapQueryStringProcessor.php
index 48446456a..273b4e0f5 100644
--- a/src/Processor/MapQueryStringProcessor.php
+++ b/src/Processor/MapQueryStringProcessor.php
@@ -29,7 +29,7 @@
  */
 final class MapQueryStringProcessor implements ProcessorInterface
 {
-    public function __invoke(Analysis $analysis)
+    public function __invoke(Analysis $analysis): void
     {
         /** @var OA\Operation[] $operations */
         $operations = $analysis->getAnnotationsOfType(OA\Operation::class);
@@ -50,6 +50,9 @@ public function __invoke(Analysis $analysis)
         }
     }
 
+    /**
+     * @param array<string, mixed> $mapQueryStringContext
+     */
     private function addQueryParameters(Analysis $analysis, OA\Operation $operation, array $mapQueryStringContext): void
     {
         $argumentMetaData = $mapQueryStringContext[SymfonyMapQueryStringDescriber::CONTEXT_ARGUMENT_METADATA];
diff --git a/src/Processor/MapRequestPayloadProcessor.php b/src/Processor/MapRequestPayloadProcessor.php
index ea86e9355..36cc345ac 100644
--- a/src/Processor/MapRequestPayloadProcessor.php
+++ b/src/Processor/MapRequestPayloadProcessor.php
@@ -30,7 +30,7 @@
  */
 final class MapRequestPayloadProcessor implements ProcessorInterface
 {
-    public function __invoke(Analysis $analysis)
+    public function __invoke(Analysis $analysis): void
     {
         /** @var OA\Operation[] $operations */
         $operations = $analysis->getAnnotationsOfType(OA\Operation::class);
diff --git a/src/PropertyDescriber/ArrayPropertyDescriber.php b/src/PropertyDescriber/ArrayPropertyDescriber.php
index 0b1287073..4f7d4230e 100644
--- a/src/PropertyDescriber/ArrayPropertyDescriber.php
+++ b/src/PropertyDescriber/ArrayPropertyDescriber.php
@@ -22,6 +22,9 @@ class ArrayPropertyDescriber implements PropertyDescriberInterface, ModelRegistr
     use ModelRegistryAwareTrait;
     use PropertyDescriberAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'array';
diff --git a/src/PropertyDescriber/BooleanPropertyDescriber.php b/src/PropertyDescriber/BooleanPropertyDescriber.php
index b90a37eb8..e6fef6172 100644
--- a/src/PropertyDescriber/BooleanPropertyDescriber.php
+++ b/src/PropertyDescriber/BooleanPropertyDescriber.php
@@ -16,6 +16,9 @@
 
 class BooleanPropertyDescriber implements PropertyDescriberInterface
 {
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'boolean';
diff --git a/src/PropertyDescriber/CompoundPropertyDescriber.php b/src/PropertyDescriber/CompoundPropertyDescriber.php
index 29686f2aa..da57a8494 100644
--- a/src/PropertyDescriber/CompoundPropertyDescriber.php
+++ b/src/PropertyDescriber/CompoundPropertyDescriber.php
@@ -22,6 +22,9 @@ class CompoundPropertyDescriber implements PropertyDescriberInterface, ModelRegi
     use ModelRegistryAwareTrait;
     use PropertyDescriberAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->oneOf = Generator::UNDEFINED !== $property->oneOf ? $property->oneOf : [];
diff --git a/src/PropertyDescriber/DateTimePropertyDescriber.php b/src/PropertyDescriber/DateTimePropertyDescriber.php
index 1e57292e5..dcddb7fbf 100644
--- a/src/PropertyDescriber/DateTimePropertyDescriber.php
+++ b/src/PropertyDescriber/DateTimePropertyDescriber.php
@@ -16,6 +16,9 @@
 
 class DateTimePropertyDescriber implements PropertyDescriberInterface
 {
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'string';
diff --git a/src/PropertyDescriber/DictionaryPropertyDescriber.php b/src/PropertyDescriber/DictionaryPropertyDescriber.php
index 0c3d31c37..8476d5716 100644
--- a/src/PropertyDescriber/DictionaryPropertyDescriber.php
+++ b/src/PropertyDescriber/DictionaryPropertyDescriber.php
@@ -22,6 +22,9 @@ final class DictionaryPropertyDescriber implements PropertyDescriberInterface, M
     use ModelRegistryAwareTrait;
     use PropertyDescriberAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'object';
diff --git a/src/PropertyDescriber/FloatPropertyDescriber.php b/src/PropertyDescriber/FloatPropertyDescriber.php
index 4dee3ef35..8749e0780 100644
--- a/src/PropertyDescriber/FloatPropertyDescriber.php
+++ b/src/PropertyDescriber/FloatPropertyDescriber.php
@@ -16,6 +16,9 @@
 
 class FloatPropertyDescriber implements PropertyDescriberInterface
 {
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'number';
diff --git a/src/PropertyDescriber/IntegerPropertyDescriber.php b/src/PropertyDescriber/IntegerPropertyDescriber.php
index 746fd9116..0d4ba17e9 100644
--- a/src/PropertyDescriber/IntegerPropertyDescriber.php
+++ b/src/PropertyDescriber/IntegerPropertyDescriber.php
@@ -16,6 +16,9 @@
 
 class IntegerPropertyDescriber implements PropertyDescriberInterface
 {
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'integer';
diff --git a/src/PropertyDescriber/NullablePropertyDescriber.php b/src/PropertyDescriber/NullablePropertyDescriber.php
index d9adad526..3666ced89 100644
--- a/src/PropertyDescriber/NullablePropertyDescriber.php
+++ b/src/PropertyDescriber/NullablePropertyDescriber.php
@@ -18,6 +18,9 @@ final class NullablePropertyDescriber implements PropertyDescriberInterface, Pro
 {
     use PropertyDescriberAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         if (Generator::UNDEFINED === $property->nullable) {
diff --git a/src/PropertyDescriber/ObjectPropertyDescriber.php b/src/PropertyDescriber/ObjectPropertyDescriber.php
index 7f065b378..e7df42c13 100644
--- a/src/PropertyDescriber/ObjectPropertyDescriber.php
+++ b/src/PropertyDescriber/ObjectPropertyDescriber.php
@@ -22,6 +22,9 @@ class ObjectPropertyDescriber implements PropertyDescriberInterface, ModelRegist
 {
     use ModelRegistryAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $type = new Type(
diff --git a/src/PropertyDescriber/PropertyDescriber.php b/src/PropertyDescriber/PropertyDescriber.php
index 7d707c15a..d820ec596 100644
--- a/src/PropertyDescriber/PropertyDescriber.php
+++ b/src/PropertyDescriber/PropertyDescriber.php
@@ -16,23 +16,30 @@
 use Nelmio\ApiDocBundle\Describer\ModelRegistryAwareInterface;
 use Nelmio\ApiDocBundle\Describer\ModelRegistryAwareTrait;
 use OpenApi\Annotations as OA;
+use Symfony\Component\PropertyInfo\Type;
 
 final class PropertyDescriber implements PropertyDescriberInterface, ModelRegistryAwareInterface
 {
     use ModelRegistryAwareTrait;
 
     /** @var array<string, PropertyDescriberInterface[]> Recursion helper */
-    private $called = [];
+    private array $called = [];
 
-    /** @var PropertyDescriberInterface[] */
-    private $propertyDescribers;
+    /** @var iterable<PropertyDescriberInterface> */
+    private iterable $propertyDescribers;
 
+    /**
+     * @param iterable<PropertyDescriberInterface> $propertyDescribers
+     */
     public function __construct(
         iterable $propertyDescribers
     ) {
         $this->propertyDescribers = $propertyDescribers;
     }
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = []): void
     {
         if (null === $propertyDescriber = $this->getPropertyDescriber($types)) {
@@ -49,11 +56,17 @@ public function supports(array $types): bool
         return null !== $this->getPropertyDescriber($types);
     }
 
+    /**
+     * @param Type[] $types
+     */
     private function getHash(array $types): string
     {
         return md5(serialize($types));
     }
 
+    /**
+     * @param Type[] $types
+     */
     private function getPropertyDescriber(array $types): ?PropertyDescriberInterface
     {
         foreach ($this->propertyDescribers as $propertyDescriber) {
diff --git a/src/PropertyDescriber/PropertyDescriberInterface.php b/src/PropertyDescriber/PropertyDescriberInterface.php
index d2ec894a2..feac04bb3 100644
--- a/src/PropertyDescriber/PropertyDescriberInterface.php
+++ b/src/PropertyDescriber/PropertyDescriberInterface.php
@@ -21,6 +21,8 @@ interface PropertyDescriberInterface
      * @param string[]|null        $groups  Deprecated use $context['groups'] instead
      * @param Schema               $schema  Allows to make changes inside of the schema (e.g. adding required fields)
      * @param array<string, mixed> $context Context options for describing the property
+     *
+     * @return void
      */
     public function describe(array $types, Schema $property, ?array $groups = null /* , ?Schema $schema = null */ /* , array $context = [] */);
 
diff --git a/src/PropertyDescriber/RequiredPropertyDescriber.php b/src/PropertyDescriber/RequiredPropertyDescriber.php
index 2709ff4df..1b8b70e68 100644
--- a/src/PropertyDescriber/RequiredPropertyDescriber.php
+++ b/src/PropertyDescriber/RequiredPropertyDescriber.php
@@ -21,6 +21,9 @@ final class RequiredPropertyDescriber implements PropertyDescriberInterface, Pro
 {
     use PropertyDescriberAwareTrait;
 
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $this->propertyDescriber->describe($types, $property, $groups, $schema, $context);
diff --git a/src/PropertyDescriber/StringPropertyDescriber.php b/src/PropertyDescriber/StringPropertyDescriber.php
index 417992ba3..f67c36e5e 100644
--- a/src/PropertyDescriber/StringPropertyDescriber.php
+++ b/src/PropertyDescriber/StringPropertyDescriber.php
@@ -16,6 +16,9 @@
 
 class StringPropertyDescriber implements PropertyDescriberInterface
 {
+    /**
+     * @param array<string, mixed> $context Context options for describing the property
+     */
     public function describe(array $types, OA\Schema $property, ?array $groups = null, ?OA\Schema $schema = null, array $context = [])
     {
         $property->type = 'string';
diff --git a/src/Render/Html/GetNelmioAsset.php b/src/Render/Html/GetNelmioAsset.php
index 0eada281e..bb15af4e8 100644
--- a/src/Render/Html/GetNelmioAsset.php
+++ b/src/Render/Html/GetNelmioAsset.php
@@ -20,9 +20,9 @@
  */
 class GetNelmioAsset extends AbstractExtension
 {
-    private $assetExtension;
-    private $resourcesDir;
-    private $cdnUrl;
+    private AssetExtension $assetExtension;
+    private string $resourcesDir;
+    private string $cdnUrl;
 
     public function __construct(AssetExtension $assetExtension)
     {
@@ -38,7 +38,7 @@ public function getFunctions(): array
         ];
     }
 
-    public function __invoke($defaultAssetsMode, $asset)
+    public function __invoke(string $defaultAssetsMode, string $asset): string
     {
         [$extension, $mode] = $this->getExtension($defaultAssetsMode, $asset);
         [$resource, $isInline] = $this->getResource($asset, $mode);
@@ -51,7 +51,10 @@ public function __invoke($defaultAssetsMode, $asset)
         }
     }
 
-    private function getExtension($assetsMode, $asset)
+    /**
+     * @return array{string, string}
+     */
+    private function getExtension(string $assetsMode, string $asset): array
     {
         $extension = mb_substr($asset, -3, 3, 'utf-8');
         if ('.js' === $extension) {
@@ -63,7 +66,10 @@ private function getExtension($assetsMode, $asset)
         }
     }
 
-    private function getResource($asset, $mode)
+    /**
+     * @return array{string, bool}
+     */
+    private function getResource(string $asset, string $mode): array
     {
         if (filter_var($asset, FILTER_VALIDATE_URL)) {
             return [$asset, false];
@@ -76,7 +82,7 @@ private function getResource($asset, $mode)
         }
     }
 
-    private function renderJavascript(string $script, bool $isInline)
+    private function renderJavascript(string $script, bool $isInline): string
     {
         if ($isInline) {
             return sprintf('<script>%s</script>', $script);
@@ -85,7 +91,7 @@ private function renderJavascript(string $script, bool $isInline)
         }
     }
 
-    private function renderCss(string $stylesheet, bool $isInline)
+    private function renderCss(string $stylesheet, bool $isInline): string
     {
         if ($isInline) {
             return sprintf('<style>%s</style>', $stylesheet);
diff --git a/src/Render/Html/HtmlOpenApiRenderer.php b/src/Render/Html/HtmlOpenApiRenderer.php
index f5181e47a..edb47d6c9 100644
--- a/src/Render/Html/HtmlOpenApiRenderer.php
+++ b/src/Render/Html/HtmlOpenApiRenderer.php
@@ -24,6 +24,9 @@ class HtmlOpenApiRenderer implements OpenApiRenderer
     /** @var Environment|\Twig_Environment */
     private $twig;
 
+    /**
+     * @param Environment|\Twig_Environment $twig
+     */
     public function __construct($twig)
     {
         if (!$twig instanceof \Twig_Environment && !$twig instanceof Environment) {
diff --git a/src/Render/Json/JsonOpenApiRenderer.php b/src/Render/Json/JsonOpenApiRenderer.php
index 12bbf378f..b903f72ae 100644
--- a/src/Render/Json/JsonOpenApiRenderer.php
+++ b/src/Render/Json/JsonOpenApiRenderer.php
@@ -30,7 +30,7 @@ public function render(OpenApi $spec, array $options = []): string
         $options += [
             'no-pretty' => false,
         ];
-        $flags = $options['no-pretty'] ? 0 : JSON_PRETTY_PRINT;
+        $flags = true === $options['no-pretty'] ? 0 : JSON_PRETTY_PRINT;
 
         return json_encode($spec, $flags | JSON_UNESCAPED_SLASHES);
     }
diff --git a/src/Render/OpenApiRenderer.php b/src/Render/OpenApiRenderer.php
index 73edb66ca..a474002ce 100644
--- a/src/Render/OpenApiRenderer.php
+++ b/src/Render/OpenApiRenderer.php
@@ -20,5 +20,8 @@ interface OpenApiRenderer
 {
     public function getFormat(): string;
 
+    /**
+     * @param array<string, mixed> $options
+     */
     public function render(OpenApi $spec, array $options = []): string;
 }
diff --git a/src/Render/RenderOpenApi.php b/src/Render/RenderOpenApi.php
index 12a2d64c4..a7d1ae5c5 100644
--- a/src/Render/RenderOpenApi.php
+++ b/src/Render/RenderOpenApi.php
@@ -25,11 +25,10 @@ class RenderOpenApi
     public const JSON = 'json';
     public const YAML = 'yaml';
 
-    /** @var ContainerInterface */
-    private $generatorLocator;
+    private ContainerInterface $generatorLocator;
 
     /** @var array<string, OpenApiRenderer|null> */
-    private $openApiRenderers = [];
+    private array $openApiRenderers = [];
 
     public function __construct(ContainerInterface $generatorLocator, ?OpenApiRenderer ...$openApiRenderers)
     {
@@ -43,12 +42,20 @@ public function __construct(ContainerInterface $generatorLocator, ?OpenApiRender
         }
     }
 
+    /**
+     * @return string[]
+     */
     public function getAvailableFormats(): array
     {
         return array_keys($this->openApiRenderers);
     }
 
-    public function renderFromRequest(Request $request, string $format, $area, array $extraOptions = [])
+    /**
+     * @param array<string, mixed> $extraOptions
+     *
+     * @return string
+     */
+    public function renderFromRequest(Request $request, string $format, string $area, array $extraOptions = [])
     {
         $options = [];
         if ('' !== $request->getBaseUrl()) {
@@ -62,6 +69,8 @@ public function renderFromRequest(Request $request, string $format, $area, array
     }
 
     /**
+     * @param array<string, mixed> $options
+     *
      * @throws \InvalidArgumentException If the area to dump is not valid
      */
     public function render(string $format, string $area, array $options = []): string
@@ -84,9 +93,14 @@ public function render(string $format, string $area, array $options = []): strin
         }
     }
 
+    /**
+     * @param array<string, mixed> $options
+     *
+     * @return Server[]|Generator::UNDEFINED
+     */
     private function getServersFromOptions(OpenApi $spec, array $options)
     {
-        if (array_key_exists('server_url', $options) && $options['server_url']) {
+        if (array_key_exists('server_url', $options)) {
             return [new Server(['url' => $options['server_url'], '_context' => new Context()])];
         }
 
@@ -94,7 +108,7 @@ private function getServersFromOptions(OpenApi $spec, array $options)
             return $spec->servers;
         }
 
-        if (array_key_exists('fallback_url', $options) && $options['fallback_url']) {
+        if (array_key_exists('fallback_url', $options)) {
             return [new Server(['url' => $options['fallback_url'], '_context' => new Context()])];
         }
 
diff --git a/src/RouteDescriber/FosRestDescriber.php b/src/RouteDescriber/FosRestDescriber.php
index e7bbeeaa9..3ee28847d 100644
--- a/src/RouteDescriber/FosRestDescriber.php
+++ b/src/RouteDescriber/FosRestDescriber.php
@@ -12,6 +12,7 @@
 namespace Nelmio\ApiDocBundle\RouteDescriber;
 
 use Doctrine\Common\Annotations\Reader;
+use FOS\RestBundle\Controller\Annotations\AbstractScalarParam;
 use FOS\RestBundle\Controller\Annotations\QueryParam;
 use FOS\RestBundle\Controller\Annotations\RequestParam;
 use Nelmio\ApiDocBundle\OpenApiPhp\Util;
@@ -27,19 +28,21 @@ final class FosRestDescriber implements RouteDescriberInterface
 {
     use RouteDescriberTrait;
 
-    /** @var Reader|null */
-    private $annotationReader;
+    private ?Reader $annotationReader;
 
     /** @var string[] */
-    private $mediaTypes;
+    private array $mediaTypes;
 
+    /**
+     * @param string[] $mediaTypes
+     */
     public function __construct(?Reader $annotationReader, array $mediaTypes)
     {
         $this->annotationReader = $annotationReader;
         $this->mediaTypes = $mediaTypes;
     }
 
-    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod)
+    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod): void
     {
         $annotations = null !== $this->annotationReader
             ? $this->annotationReader->getMethodAnnotations($reflectionMethod)
@@ -91,7 +94,10 @@ public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $refle
         }
     }
 
-    private function getPattern($requirements)
+    /**
+     * @param mixed $requirements Value to retrieve a pattern from
+     */
+    private function getPattern($requirements): ?string
     {
         if (is_array($requirements) && isset($requirements['rule'])) {
             return (string) $requirements['rule'];
@@ -108,7 +114,10 @@ private function getPattern($requirements)
         return null;
     }
 
-    private function getFormat($requirements)
+    /**
+     * @param mixed $requirements Value to retrieve a format from
+     */
+    private function getFormat($requirements): ?string
     {
         if ($requirements instanceof Constraint && !$requirements instanceof Regex) {
             if ($requirements instanceof DateTime) {
@@ -132,7 +141,12 @@ private function getFormat($requirements)
         return null;
     }
 
-    private function getEnum($requirements)
+    /**
+     * @param mixed $requirements Value to retrieve an enum from
+     *
+     * @return mixed[]|null
+     */
+    private function getEnum($requirements): ?array
     {
         if ($requirements instanceof Choice) {
             return $requirements->choices;
@@ -178,7 +192,7 @@ private function getContentSchemaForType(OA\RequestBody $requestBody, string $ty
         );
     }
 
-    private function describeCommonSchemaFromAnnotation(OA\Schema $schema, $annotation)
+    private function describeCommonSchemaFromAnnotation(OA\Schema $schema, AbstractScalarParam $annotation): void
     {
         $schema->default = $annotation->getDefault();
 
@@ -208,7 +222,11 @@ private function describeCommonSchemaFromAnnotation(OA\Schema $schema, $annotati
     }
 
     /**
-     * @return OA\AbstractAnnotation[]
+     * @template T of object
+     *
+     * @param class-string<T> $className
+     *
+     * @return T[]
      */
     private function getAttributesAsAnnotation(\ReflectionMethod $reflection, string $className): array
     {
diff --git a/src/RouteDescriber/PhpDocDescriber.php b/src/RouteDescriber/PhpDocDescriber.php
index fcde8d6e5..566568cbd 100644
--- a/src/RouteDescriber/PhpDocDescriber.php
+++ b/src/RouteDescriber/PhpDocDescriber.php
@@ -21,7 +21,7 @@ final class PhpDocDescriber implements RouteDescriberInterface
 {
     use RouteDescriberTrait;
 
-    private $docBlockFactory;
+    private ?DocBlockFactoryInterface $docBlockFactory;
 
     public function __construct(?DocBlockFactoryInterface $docBlockFactory = null)
     {
@@ -31,7 +31,7 @@ public function __construct(?DocBlockFactoryInterface $docBlockFactory = null)
         $this->docBlockFactory = $docBlockFactory;
     }
 
-    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod)
+    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod): void
     {
         $classDocBlock = null;
         $docBlock = null;
diff --git a/src/RouteDescriber/RouteArgumentDescriber/SymfonyMapQueryParameterDescriber.php b/src/RouteDescriber/RouteArgumentDescriber/SymfonyMapQueryParameterDescriber.php
index 137bca56c..6cc5ea9f8 100644
--- a/src/RouteDescriber/RouteArgumentDescriber/SymfonyMapQueryParameterDescriber.php
+++ b/src/RouteDescriber/RouteArgumentDescriber/SymfonyMapQueryParameterDescriber.php
@@ -72,6 +72,10 @@ public function describe(ArgumentMetadata $argumentMetadata, OA\Operation $opera
     }
 
     /**
+     * @param mixed[] $options
+     *
+     * @return array<string, mixed>
+     *
      * @see https://www.php.net/manual/en/filter.filters.validate.php
      */
     private function describeValidateFilter(?int $filter, int $flags, array $options): array
@@ -98,11 +102,11 @@ private function describeValidateFilter(?int $filter, int $flags, array $options
 
         if (FILTER_VALIDATE_INT === $filter) {
             $props = [];
-            if ($options['min_range'] ?? false) {
+            if (array_key_exists('min_range', $options)) {
                 $props['minimum'] = $options['min_range'];
             }
 
-            if ($options['max_range'] ?? false) {
+            if (array_key_exists('max_range', $options)) {
                 $props['maximum'] = $options['max_range'];
             }
 
diff --git a/src/RouteDescriber/RouteDescriberInterface.php b/src/RouteDescriber/RouteDescriberInterface.php
index 9067c60df..19ad2e036 100644
--- a/src/RouteDescriber/RouteDescriberInterface.php
+++ b/src/RouteDescriber/RouteDescriberInterface.php
@@ -16,5 +16,8 @@
 
 interface RouteDescriberInterface
 {
+    /**
+     * @return void
+     */
     public function describe(OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod);
 }
diff --git a/src/RouteDescriber/RouteMetadataDescriber.php b/src/RouteDescriber/RouteMetadataDescriber.php
index 96bb6e278..b881bead7 100644
--- a/src/RouteDescriber/RouteMetadataDescriber.php
+++ b/src/RouteDescriber/RouteMetadataDescriber.php
@@ -25,7 +25,7 @@ final class RouteMetadataDescriber implements RouteDescriberInterface
 
     private const ALPHANUM_EXPANDED_REGEX = '/^[-a-zA-Z0-9_]*$/';
 
-    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod)
+    public function describe(OA\OpenApi $api, Route $route, \ReflectionMethod $reflectionMethod): void
     {
         foreach ($this->getOperations($api, $route) as $operation) {
             $requirements = $route->getRequirements();
diff --git a/src/Routing/FilteredRouteCollectionBuilder.php b/src/Routing/FilteredRouteCollectionBuilder.php
index eef2dc4a9..b634f8702 100644
--- a/src/Routing/FilteredRouteCollectionBuilder.php
+++ b/src/Routing/FilteredRouteCollectionBuilder.php
@@ -21,18 +21,20 @@
 
 final class FilteredRouteCollectionBuilder
 {
-    /** @var Reader|null */
-    private $annotationReader;
+    private ?Reader $annotationReader;
 
-    /** @var ControllerReflector */
-    private $controllerReflector;
+    private ControllerReflector $controllerReflector;
 
-    /** @var string */
-    private $area;
+    private string $area;
 
-    /** @var array */
-    private $options;
+    /**
+     * @var array<string, mixed>
+     */
+    private array $options;
 
+    /**
+     * @param array<mixed> $options
+     */
     public function __construct(
         ?Reader $annotationReader,
         ControllerReflector $controllerReflector,
diff --git a/src/Util/ControllerReflector.php b/src/Util/ControllerReflector.php
index b63ea72c1..c986bcfdf 100644
--- a/src/Util/ControllerReflector.php
+++ b/src/Util/ControllerReflector.php
@@ -18,9 +18,11 @@
  */
 class ControllerReflector
 {
-    private $container;
-
-    private $controllers = [];
+    private ContainerInterface $container;
+    /**
+     * @var array<string, array{string, string}|null>
+     */
+    private array $controllers = [];
 
     public function __construct(ContainerInterface $container)
     {
@@ -29,6 +31,8 @@ public function __construct(ContainerInterface $container)
 
     /**
      * Returns the ReflectionMethod for the given controller string.
+     *
+     * @param string|array{string, string}|null $controller
      */
     public function getReflectionMethod($controller): ?\ReflectionMethod
     {
@@ -54,6 +58,9 @@ private function getReflectionMethodByClassNameAndMethodName(string $class, stri
         return null;
     }
 
+    /**
+     * @return array{string, string}|null
+     */
     private function getClassAndMethod(string $controller): ?array
     {
         if (isset($this->controllers[$controller])) {
diff --git a/src/Util/SetsContextTrait.php b/src/Util/SetsContextTrait.php
index 1a9166db7..27e51f307 100644
--- a/src/Util/SetsContextTrait.php
+++ b/src/Util/SetsContextTrait.php
@@ -25,6 +25,9 @@ private function setContext(?Context $context): void
         \OpenApi\Generator::$context = $context;
     }
 
+    /**
+     * @param \ReflectionClass|\ReflectionProperty|\ReflectionMethod $reflection
+     */
     private function setContextFromReflection(Context $parentContext, $reflection): void
     {
         // In order to have nicer errors
diff --git a/tests/ApiDocGeneratorTest.php b/tests/ApiDocGeneratorTest.php
index 02b0bd3fb..223e72bb5 100644
--- a/tests/ApiDocGeneratorTest.php
+++ b/tests/ApiDocGeneratorTest.php
@@ -19,7 +19,7 @@
 
 class ApiDocGeneratorTest extends TestCase
 {
-    public function testCache()
+    public function testCache(): void
     {
         $adapter = new ArrayAdapter();
         $generator = new ApiDocGenerator([new DefaultDescriber()], [], $adapter, null, new Generator());
@@ -27,7 +27,7 @@ public function testCache()
         self::assertEquals(json_encode($generator->generate()), json_encode($adapter->getItem('openapi_doc')->get()));
     }
 
-    public function testCacheWithCustomId()
+    public function testCacheWithCustomId(): void
     {
         $adapter = new ArrayAdapter();
         $generator = new ApiDocGenerator([new DefaultDescriber()], [], $adapter, 'custom_id', new Generator());
diff --git a/tests/Command/DumpCommandTest.php b/tests/Command/DumpCommandTest.php
index 62d5ced0b..5c4374513 100644
--- a/tests/Command/DumpCommandTest.php
+++ b/tests/Command/DumpCommandTest.php
@@ -18,8 +18,12 @@
 
 class DumpCommandTest extends WebTestCase
 {
-    /** @dataProvider provideJsonMode */
-    public function testJson(array $jsonOptions, int $expectedJsonFlags)
+    /**
+     * @dataProvider provideJsonMode
+     *
+     * @param array<string, mixed> $jsonOptions
+     */
+    public function testJson(array $jsonOptions, int $expectedJsonFlags): void
     {
         $output = $this->executeDumpCommand($jsonOptions + [
             '--area' => 'test',
@@ -30,15 +34,14 @@ public function testJson(array $jsonOptions, int $expectedJsonFlags)
         );
     }
 
-    public static function provideJsonMode(): iterable
+    public static function provideJsonMode(): \Generator
     {
-        return [
-            'pretty print' => [[], JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES],
-            'one line' => [['--no-pretty'], 0 | JSON_UNESCAPED_SLASHES],
-        ];
+        yield 'pretty print' => [[], JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES];
+
+        yield 'one line' => [['--no-pretty'], 0 | JSON_UNESCAPED_SLASHES];
     }
 
-    public function testYaml()
+    public function testYaml(): void
     {
         $output = $this->executeDumpCommand([
             '--format' => 'yaml',
@@ -52,8 +55,12 @@ public function testYaml()
         self::assertStringContainsString($expectedYaml, $output);
     }
 
-    /** @dataProvider provideAssetsMode */
-    public function testHtml($htmlConfig, string $expectedHtml)
+    /**
+     * @dataProvider provideAssetsMode
+     *
+     * @param mixed $htmlConfig the value of the --html-config option
+     */
+    public function testHtml($htmlConfig, string $expectedHtml): void
     {
         $output = $this->executeDumpCommand([
             '--area' => 'test',
@@ -64,43 +71,49 @@ public function testHtml($htmlConfig, string $expectedHtml)
         self::assertStringContainsString($expectedHtml, $output);
     }
 
-    public static function provideAssetsMode(): iterable
+    public static function provideAssetsMode(): \Generator
     {
-        return [
-            'default mode is cdn' => [
-                null,
-                'https://cdn.jsdelivr.net',
-            ],
-            'invalid mode fallbacks to cdn' => [
-                'invalid',
-                'https://cdn.jsdelivr.net',
-            ],
-            'select cdn mode' => [
-                ['assets_mode' => AssetsMode::CDN],
-                'https://cdn.jsdelivr.net',
-            ],
-            'select offline mode' => [
-                ['assets_mode' => AssetsMode::OFFLINE],
-                '<style>',
-            ],
-            'configure swagger ui' => [
-                [
-                    'swagger_ui_config' => [
-                        'supportedSubmitMethods' => ['get'],
-                    ],
+        yield 'default mode is cdn' => [
+            null,
+            'https://cdn.jsdelivr.net',
+        ];
+
+        yield 'invalid mode fallbacks to cdn' => [
+            'invalid',
+            'https://cdn.jsdelivr.net',
+        ];
+
+        yield 'select cdn mode' => [
+            ['assets_mode' => AssetsMode::CDN],
+            'https://cdn.jsdelivr.net',
+        ];
+
+        yield 'select offline mode' => [
+            ['assets_mode' => AssetsMode::OFFLINE],
+            '<style>',
+        ];
+
+        yield 'configure swagger ui' => [
+            [
+                'swagger_ui_config' => [
+                    'supportedSubmitMethods' => ['get'],
                 ],
-                '"supportedSubmitMethods":["get"]',
             ],
-            'configure server url' => [
-                [
-                    'server_url' => 'http://example.com/api',
-                ],
-                '[{"url":"http://example.com/api"}]',
+            '"supportedSubmitMethods":["get"]',
+        ];
+
+        yield 'configure server url' => [
+            [
+                'server_url' => 'http://example.com/api',
             ],
+            '[{"url":"http://example.com/api"}]',
         ];
     }
 
-    private function executeDumpCommand(array $options)
+    /**
+     * @param array<string, mixed> $options
+     */
+    private function executeDumpCommand(array $options): string
     {
         $kernel = static::bootKernel();
         $application = new Application($kernel);
diff --git a/tests/DependencyInjection/ConfigurationTest.php b/tests/DependencyInjection/ConfigurationTest.php
index bb042df56..29ca68211 100644
--- a/tests/DependencyInjection/ConfigurationTest.php
+++ b/tests/DependencyInjection/ConfigurationTest.php
@@ -17,7 +17,7 @@
 
 class ConfigurationTest extends TestCase
 {
-    public function testDefaultArea()
+    public function testDefaultArea(): void
     {
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(), [['areas' => ['path_patterns' => ['/foo']]]]);
@@ -37,7 +37,7 @@ public function testDefaultArea()
         );
     }
 
-    public function testAreas()
+    public function testAreas(): void
     {
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(), [['areas' => $areas = [
@@ -70,7 +70,7 @@ public function testAreas()
         self::assertSame($areas, $config['areas']);
     }
 
-    public function testAlternativeNames()
+    public function testAlternativeNames(): void
     {
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(), [[
diff --git a/tests/DependencyInjection/NelmioApiDocExtensionTest.php b/tests/DependencyInjection/NelmioApiDocExtensionTest.php
index 9b16b9afe..c62bde577 100644
--- a/tests/DependencyInjection/NelmioApiDocExtensionTest.php
+++ b/tests/DependencyInjection/NelmioApiDocExtensionTest.php
@@ -18,7 +18,7 @@
 
 class NelmioApiDocExtensionTest extends TestCase
 {
-    public function testNameAliasesArePassedToModelRegistry()
+    public function testNameAliasesArePassedToModelRegistry(): void
     {
         $container = new ContainerBuilder();
         $container->setParameter('kernel.bundles', []);
@@ -86,7 +86,7 @@ public function testNameAliasesArePassedToModelRegistry()
         self::assertTrue($foundMethodCall);
     }
 
-    public function testMergesRootKeysFromMultipleConfigurations()
+    public function testMergesRootKeysFromMultipleConfigurations(): void
     {
         $container = new ContainerBuilder();
         $container->setParameter('kernel.bundles', []);
@@ -154,8 +154,11 @@ public function testMergesRootKeysFromMultipleConfigurations()
 
     /**
      * @dataProvider provideCacheConfig
+     *
+     * @param array<string, mixed> $config
+     * @param array<string, mixed> $expectedValues
      */
-    public function testApiDocGeneratorWithCachePool(array $config, array $expectedValues)
+    public function testApiDocGeneratorWithCachePool(array $config, array $expectedValues): void
     {
         $container = new ContainerBuilder();
         $container->setParameter('kernel.bundles', []);
@@ -186,7 +189,7 @@ public function testApiDocGeneratorWithCachePool(array $config, array $expectedV
         self::assertSame($expectedValues['area1CacheItemId'], $cacheItemId);
     }
 
-    public static function provideCacheConfig(): iterable
+    public static function provideCacheConfig(): \Generator
     {
         yield 'default cache.item_id & area appending' => [
             'config' => [
diff --git a/tests/Describer/ApiPlatformDescriberTest.php b/tests/Describer/ApiPlatformDescriberTest.php
index 1439874c7..7f75f4ed5 100644
--- a/tests/Describer/ApiPlatformDescriberTest.php
+++ b/tests/Describer/ApiPlatformDescriberTest.php
@@ -16,15 +16,19 @@
 use Nelmio\ApiDocBundle\Describer\ApiPlatformDescriber;
 use OpenApi\Annotations\OpenApi;
 use OpenApi\Context;
+use PHPUnit\Framework\MockObject\MockObject;
 use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
 
 class ApiPlatformDescriberTest extends AbstractDescriberTestCase
 {
-    private $documentation;
+    private Documentation $documentation;
 
-    private $normalizer;
+    /**
+     * @var MockObject&NormalizerInterface
+     */
+    private NormalizerInterface $normalizer;
 
-    public function testDescribe()
+    public function testDescribe(): void
     {
         $this->normalizer->expects(self::once())
             ->method('normalize')
@@ -35,7 +39,7 @@ public function testDescribe()
         self::assertEquals($expectedApi->toJson(), $this->getOpenApiDoc()->toJson());
     }
 
-    public function testDescribeRemovesBasePathAfterNormalization()
+    public function testDescribeRemovesBasePathAfterNormalization(): void
     {
         $this->normalizer->expects(self::once())
             ->method('normalize')
diff --git a/tests/Describer/RouteDescriberTest.php b/tests/Describer/RouteDescriberTest.php
index 005f67e86..e533ec663 100644
--- a/tests/Describer/RouteDescriberTest.php
+++ b/tests/Describer/RouteDescriberTest.php
@@ -16,17 +16,21 @@
 use Nelmio\ApiDocBundle\Util\ControllerReflector;
 use OpenApi\Annotations\OpenApi;
 use OpenApi\Context;
+use PHPUnit\Framework\MockObject\MockObject;
 use Symfony\Component\DependencyInjection\Container;
 use Symfony\Component\Routing\Route;
 use Symfony\Component\Routing\RouteCollection;
 
 class RouteDescriberTest extends AbstractDescriberTestCase
 {
-    private $routes;
+    private RouteCollection $routes;
 
-    private $routeDescriber;
+    /**
+     * @var MockObject&RouteDescriberInterface
+     */
+    private RouteDescriberInterface $routeDescriber;
 
-    public function testIgnoreWhenNoController()
+    public function testIgnoreWhenNoController(): void
     {
         $this->routes->add('foo', new Route('foo'));
         $this->routeDescriber->expects(self::never())
diff --git a/tests/Functional/BazingaFunctionalTest.php b/tests/Functional/BazingaFunctionalTest.php
index 82044457f..9e368f7f3 100644
--- a/tests/Functional/BazingaFunctionalTest.php
+++ b/tests/Functional/BazingaFunctionalTest.php
@@ -40,7 +40,7 @@ protected function setUp(): void
         $metaDataFactory->setCache(new PsrCacheAdapter('BazingaFunctionalTest', new ArrayAdapter()));
     }
 
-    public function testModelComplexDocumentationBazinga()
+    public function testModelComplexDocumentationBazinga(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -94,7 +94,7 @@ public function testModelComplexDocumentationBazinga()
         ], json_decode($this->getModel('BazingaUser')->toJson(), true));
     }
 
-    public function testWithGroup()
+    public function testWithGroup(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -112,7 +112,7 @@ public function testWithGroup()
         ], json_decode($this->getModel('BazingaUser_grouped')->toJson(), true));
     }
 
-    public function testWithType()
+    public function testWithType(): void
     {
         if (!method_exists(Embedded::class, 'getType')) {
             self::markTestSkipped('Typed embedded properties require at most willdurand/hateoas 3.0');
@@ -140,6 +140,9 @@ public function testWithType()
         ], json_decode($this->getModel('BazingaUserTyped')->toJson(), true));
     }
 
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel(TestKernel::USE_BAZINGA);
diff --git a/tests/Functional/Controller/TestController.php b/tests/Functional/Controller/TestController.php
index 68bb702af..2add3d8b0 100644
--- a/tests/Functional/Controller/TestController.php
+++ b/tests/Functional/Controller/TestController.php
@@ -30,7 +30,7 @@ class TestController
          *
          * @Route("/test/", methods={"GET"})
          */
-        public function testAction()
+        public function testAction(): void
         {
         }
     }
@@ -40,7 +40,7 @@ class TestController
     {
         #[OAT\Response(response: 200, description: 'Test')]
         #[Route('/test/', methods: ['GET'])]
-        public function testAction()
+        public function testAction(): void
         {
         }
     }
diff --git a/tests/Functional/ControllerTest.php b/tests/Functional/ControllerTest.php
index 96861abd4..dd624bfea 100644
--- a/tests/Functional/ControllerTest.php
+++ b/tests/Functional/ControllerTest.php
@@ -33,12 +33,15 @@ protected function setUp(): void
         static::createClient([], ['HTTP_HOST' => 'api.example.com']);
     }
 
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new NelmioKernel([], null, []);
     }
 
-    protected function getOpenApiDefinition($area = 'default'): OA\OpenApi
+    protected function getOpenApiDefinition(string $area = 'default'): OA\OpenApi
     {
         return $this->configurableContainerFactory->getContainer()->get(sprintf('nelmio_api_doc.generator.%s', $area))->generate();
     }
@@ -81,7 +84,7 @@ public function testControllers(?array $controller, ?string $fixtureName = null,
         );
     }
 
-    public static function provideAttributeTestCases(): iterable
+    public static function provideAttributeTestCases(): \Generator
     {
         if (PHP_VERSION_ID < 80100) {
             return;
@@ -122,7 +125,7 @@ public static function provideAttributeTestCases(): iterable
         }
     }
 
-    public static function provideAnnotationTestCases(): iterable
+    public static function provideAnnotationTestCases(): \Generator
     {
         if (!TestKernel::isAnnotationsAvailable()) {
             return;
@@ -143,7 +146,7 @@ public static function provideAnnotationTestCases(): iterable
     /**
      * Test cases that are universal and can be run without depending on the existence of a specific feature.
      */
-    public static function provideUniversalTestCases(): iterable
+    public static function provideUniversalTestCases(): \Generator
     {
         yield 'https://github.com/nelmio/NelmioApiDocBundle/issues/2224' => [
             null,
diff --git a/tests/Functional/CsrfProtectionFunctionalTest.php b/tests/Functional/CsrfProtectionFunctionalTest.php
index 58375b20a..0c5174965 100644
--- a/tests/Functional/CsrfProtectionFunctionalTest.php
+++ b/tests/Functional/CsrfProtectionFunctionalTest.php
@@ -21,6 +21,9 @@ protected function setUp(): void
         static::bootKernel();
     }
 
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel(TestKernel::USE_FORM_CSRF);
diff --git a/tests/Functional/FOSRestTest.php b/tests/Functional/FOSRestTest.php
index 507896c5e..c994d5899 100644
--- a/tests/Functional/FOSRestTest.php
+++ b/tests/Functional/FOSRestTest.php
@@ -17,6 +17,9 @@
 
 class FOSRestTest extends WebTestCase
 {
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel(TestKernel::USE_FOSREST);
@@ -32,7 +35,7 @@ protected function setUp(): void
     /**
      * @dataProvider provideRoute
      */
-    public function testFOSRestAction(string $route)
+    public function testFOSRestAction(string $route): void
     {
         $operation = $this->getOperation($route, 'post');
 
@@ -76,7 +79,7 @@ public function testFOSRestAction(string $route)
         self::assertNotHasParameter('_format', 'path', $operation);
     }
 
-    public static function provideRoute(): iterable
+    public static function provideRoute(): \Generator
     {
         yield 'Annotations' => ['/api/fosrest'];
 
diff --git a/tests/Functional/FunctionalTest.php b/tests/Functional/FunctionalTest.php
index 15145d506..88ff470ff 100644
--- a/tests/Functional/FunctionalTest.php
+++ b/tests/Functional/FunctionalTest.php
@@ -29,14 +29,14 @@ protected function setUp(): void
         static::createClient([], ['HTTP_HOST' => 'api.example.com']);
     }
 
-    public function testConfiguredDocumentation()
+    public function testConfiguredDocumentation(): void
     {
         self::assertEquals('My Default App', $this->getOpenApiDefinition()->info->title);
         self::assertEquals(['buildHash' => 'ab1234567890'], $this->getOpenApiDefinition()->info->x);
         self::assertEquals('My Test App', $this->getOpenApiDefinition('test')->info->title);
     }
 
-    public function testUndocumentedAction()
+    public function testUndocumentedAction(): void
     {
         $api = $this->getOpenApiDefinition();
 
@@ -47,7 +47,7 @@ public function testUndocumentedAction()
     /**
      * @dataProvider provideArticleRoute
      */
-    public function testFetchArticleAction(string $articleRoute)
+    public function testFetchArticleAction(string $articleRoute): void
     {
         $operation = $this->getOperation($articleRoute, 'get');
 
@@ -63,7 +63,7 @@ public function testFetchArticleAction(string $articleRoute)
         $this->assertNotHasProperty('author', Util::getProperty($articleModel, 'author'));
     }
 
-    public static function provideArticleRoute(): iterable
+    public static function provideArticleRoute(): \Generator
     {
         if (interface_exists(Reader::class)) {
             yield 'Annotations' => ['/api/article/{id}'];
@@ -74,7 +74,7 @@ public static function provideArticleRoute(): iterable
         }
     }
 
-    public function testFilteredAction()
+    public function testFilteredAction(): void
     {
         $openApi = $this->getOpenApiDefinition();
 
@@ -86,7 +86,7 @@ public function testFilteredAction()
      *
      * @dataProvider swaggerActionPathsProvider
      */
-    public function testSwaggerAction(string $path)
+    public function testSwaggerAction(string $path): void
     {
         $operation = $this->getOperation($path, 'get');
 
@@ -95,12 +95,14 @@ public function testSwaggerAction(string $path)
         self::assertEquals('An example resource', $response->description);
     }
 
-    public static function swaggerActionPathsProvider(): iterable
+    public static function swaggerActionPathsProvider(): \Generator
     {
-        return [['/api/swagger'], ['/api/swagger2']];
+        yield ['/api/swagger'];
+
+        yield ['/api/swagger2'];
     }
 
-    public function testAnnotationWithManualPath()
+    public function testAnnotationWithManualPath(): void
     {
         $path = $this->getPath('/api/swagger2');
         self::assertSame(Generator::UNDEFINED, $path->post);
@@ -115,7 +117,7 @@ public function testAnnotationWithManualPath()
     /**
      * @dataProvider implicitSwaggerActionMethodsProvider
      */
-    public function testImplicitSwaggerAction(string $method)
+    public function testImplicitSwaggerAction(string $method): void
     {
         $operation = $this->getOperation('/api/swagger/implicit', $method);
 
@@ -133,12 +135,14 @@ public function testImplicitSwaggerAction(string $method)
         self::assertEquals('#/components/schemas/User', $requestBody->content['application/json']->schema->items->ref);
     }
 
-    public static function implicitSwaggerActionMethodsProvider(): iterable
+    public static function implicitSwaggerActionMethodsProvider(): \Generator
     {
-        return [['get'], ['post']];
+        yield ['get'];
+
+        yield ['post'];
     }
 
-    public function testUserAction()
+    public function testUserAction(): void
     {
         $operation = $this->getOperation('/api/test/{user}', 'get');
 
@@ -156,7 +160,7 @@ public function testUserAction()
         self::assertEquals(Generator::UNDEFINED, $parameter->schema->format);
     }
 
-    public function testDeprecatedAction()
+    public function testDeprecatedAction(): void
     {
         $operation = $this->getOperation('/api/deprecated', 'get');
 
@@ -165,7 +169,7 @@ public function testDeprecatedAction()
         self::assertTrue($operation->deprecated);
     }
 
-    public function testApiPlatform()
+    public function testApiPlatform(): void
     {
         $operation = $this->getOperation('/api/dummies', 'get');
         $operation = $this->getOperation('/api/foo', 'get');
@@ -173,7 +177,7 @@ public function testApiPlatform()
         $operation = $this->getOperation('/api/dummies/{id}', 'get');
     }
 
-    public function testUserModel()
+    public function testUserModel(): void
     {
         self::assertEquals(
             [
@@ -259,7 +263,7 @@ public function testUserModel()
         );
     }
 
-    public function testFormSupport()
+    public function testFormSupport(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -372,7 +376,7 @@ public function testFormSupport()
     /**
      * @dataProvider provideSecurityRoute
      */
-    public function testSecurityAction(string $route)
+    public function testSecurityAction(string $route): void
     {
         $operation = $this->getOperation($route, 'get');
 
@@ -384,7 +388,7 @@ public function testSecurityAction(string $route)
         self::assertEquals($expected, $operation->security);
     }
 
-    public static function provideSecurityRoute(): iterable
+    public static function provideSecurityRoute(): \Generator
     {
         yield 'Annotations' => ['/api/security'];
 
@@ -396,13 +400,13 @@ public static function provideSecurityRoute(): iterable
     /**
      * @dataProvider provideSecurityOverrideRoute
      */
-    public function testSecurityOverrideAction(string $route)
+    public function testSecurityOverrideAction(string $route): void
     {
         $operation = $this->getOperation($route, 'get');
         self::assertEquals([], $operation->security);
     }
 
-    public static function provideSecurityOverrideRoute(): iterable
+    public static function provideSecurityOverrideRoute(): \Generator
     {
         yield 'Annotations' => ['/api/securityOverride'];
 
@@ -411,7 +415,7 @@ public static function provideSecurityOverrideRoute(): iterable
         }
     }
 
-    public function testInlinePHP81Parameters()
+    public function testInlinePHP81Parameters(): void
     {
         if (\PHP_VERSION_ID < 80100) {
             self::markTestSkipped('Attributes require PHP 8.1');
@@ -424,7 +428,7 @@ public function testInlinePHP81Parameters()
         self::assertSame($operation->parameters[0]->schema->type, 'string');
     }
 
-    public function testClassSecurityAction()
+    public function testClassSecurityAction(): void
     {
         $operation = $this->getOperation('/api/security/class', 'get');
 
@@ -434,7 +438,7 @@ public function testClassSecurityAction()
         self::assertEquals($expected, $operation->security);
     }
 
-    public function testSymfonyConstraintDocumentation()
+    public function testSymfonyConstraintDocumentation(): void
     {
         if (TestKernel::isAttributesAvailable()) {
             $modelName = 'SymfonyConstraints81';
@@ -575,14 +579,14 @@ public function testSymfonyConstraintDocumentation()
         self::assertEquals($expected, json_decode($this->getModel($modelName)->toJson(), true));
     }
 
-    public function testConfigReference()
+    public function testConfigReference(): void
     {
         $operation = $this->getOperation('/api/configReference', 'get');
         self::assertEquals('#/components/schemas/Test', $this->getOperationResponse($operation, '200')->ref);
         self::assertEquals('#/components/responses/201', $this->getOperationResponse($operation, '201')->ref);
     }
 
-    public function testOperationsWithOtherAnnotationsAction()
+    public function testOperationsWithOtherAnnotationsAction(): void
     {
         $getOperation = $this->getOperation('/api/multi-annotations', 'get');
         self::assertSame('This is the get operation', $getOperation->description);
@@ -593,13 +597,13 @@ public function testOperationsWithOtherAnnotationsAction()
         self::assertSame('Worked well!', $this->getOperationResponse($postOperation, 200)->description);
     }
 
-    public function testNoDuplicatedParameters()
+    public function testNoDuplicatedParameters(): void
     {
         $this->assertHasPath('/api/article/{id}', $this->getOpenApiDefinition());
         $this->assertNotHasParameter('id', 'path', $this->getOperation('/api/article/{id}', 'get'));
     }
 
-    public function testSerializedNameAction()
+    public function testSerializedNameAction(): void
     {
         if (!class_exists(SerializedName::class)) {
             self::markTestSkipped('Annotation @SerializedName doesn\'t exist.');
@@ -620,7 +624,7 @@ public function testSerializedNameAction()
         $this->assertHasProperty('notwhatyouthink', $model);
     }
 
-    public function testCompoundEntityAction()
+    public function testCompoundEntityAction(): void
     {
         self::assertEquals([
             'schema' => 'CompoundEntity',
@@ -744,19 +748,19 @@ public function testCompoundEntityAction()
         ], json_decode($this->getModel('CompoundEntityNested')->toJson(), true));
     }
 
-    public function testInvokableController()
+    public function testInvokableController(): void
     {
         $operation = $this->getOperation('/api/invoke', 'get');
         self::assertSame('Invokable!', $this->getOperationResponse($operation, 200)->description);
     }
 
-    public function testDefaultOperationId()
+    public function testDefaultOperationId(): void
     {
         $operation = $this->getOperation('/api/article/{id}', 'get');
         self::assertEquals('get_api_nelmio_apidoc_tests_functional_api_fetcharticle', $operation->operationId);
     }
 
-    public function testNamedRouteOperationId()
+    public function testNamedRouteOperationId(): void
     {
         $operation = $this->getOperation('/api/named_route-operation-id', 'get');
         self::assertEquals('get_api_named_route_operation_id', $operation->operationId);
@@ -765,7 +769,7 @@ public function testNamedRouteOperationId()
         self::assertEquals('post_api_named_route_operation_id', $operation->operationId);
     }
 
-    public function testCustomOperationId()
+    public function testCustomOperationId(): void
     {
         $operation = $this->getOperation('/api/custom-operation-id', 'get');
         self::assertEquals('get-custom-operation-id', $operation->operationId);
@@ -778,7 +782,7 @@ public function testCustomOperationId()
      * Related to https://github.com/nelmio/NelmioApiDocBundle/issues/1756
      * Ensures private/protected properties are not exposed, just like the symfony serializer does.
      */
-    public function testPrivateProtectedExposure()
+    public function testPrivateProtectedExposure(): void
     {
         // Ensure that groups are supported
         $model = $this->getModel('PrivateProtectedExposure');
@@ -789,7 +793,7 @@ public function testPrivateProtectedExposure()
         $this->assertNotHasProperty('protected', $model);
     }
 
-    public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphism()
+    public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphism(): void
     {
         if (TestKernel::isAttributesAvailable()) {
             $model = $this->getModel('SymfonyDiscriminator81');
@@ -806,7 +810,7 @@ public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphism()
         self::assertCount(2, $model->oneOf);
     }
 
-    public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphismWhenUsingFileConfiguration()
+    public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphismWhenUsingFileConfiguration(): void
     {
         $model = $this->getModel('SymfonyDiscriminatorFileMapping');
 
@@ -819,14 +823,14 @@ public function testModelsWithDiscriminatorMapAreLoadedWithOpenApiPolymorphismWh
         self::assertCount(2, $model->oneOf);
     }
 
-    public function testDiscriminatorMapLoadsChildrenModels()
+    public function testDiscriminatorMapLoadsChildrenModels(): void
     {
         // get model does its own assertions
         $this->getModel('SymfonyDiscriminatorOne');
         $this->getModel('SymfonyDiscriminatorTwo');
     }
 
-    public function testNoAdditionalPropertiesSupport()
+    public function testNoAdditionalPropertiesSupport(): void
     {
         $model = $this->getModel('AddProp');
 
@@ -836,7 +840,7 @@ public function testNoAdditionalPropertiesSupport()
     /**
      * @requires PHP >= 8.1
      */
-    public function testEnumSupport()
+    public function testEnumSupport(): void
     {
         $model = $this->getModel('ArticleType81');
 
@@ -879,7 +883,7 @@ public function testEnumSupport()
         ], json_decode($this->getModel('Article81')->toJson(), true));
     }
 
-    public function testEntitiesWithOverriddenSchemaTypeDoNotReadOtherProperties()
+    public function testEntitiesWithOverriddenSchemaTypeDoNotReadOtherProperties(): void
     {
         if (TestKernel::isAttributesAvailable()) {
             $model = $this->getModel('EntityWithAlternateType81');
@@ -892,7 +896,7 @@ public function testEntitiesWithOverriddenSchemaTypeDoNotReadOtherProperties()
         self::assertSame(Generator::UNDEFINED, $model->properties);
     }
 
-    public function testEntitiesWithRefInSchemaDoNoReadOtherProperties()
+    public function testEntitiesWithRefInSchemaDoNoReadOtherProperties(): void
     {
         $model = $this->getModel('EntityWithRef');
 
@@ -901,7 +905,7 @@ public function testEntitiesWithRefInSchemaDoNoReadOtherProperties()
         self::assertSame(Generator::UNDEFINED, $model->properties);
     }
 
-    public function testEntitiesWithObjectTypeStillReadProperties()
+    public function testEntitiesWithObjectTypeStillReadProperties(): void
     {
         $model = $this->getModel('EntityWithObjectType');
 
@@ -911,7 +915,7 @@ public function testEntitiesWithObjectTypeStillReadProperties()
         self::assertSame('string', $property->type);
     }
 
-    public function testFormsWithOverriddenSchemaTypeDoNotReadOtherProperties()
+    public function testFormsWithOverriddenSchemaTypeDoNotReadOtherProperties(): void
     {
         $model = $this->getModel('FormWithAlternateSchemaType');
 
@@ -919,7 +923,7 @@ public function testFormsWithOverriddenSchemaTypeDoNotReadOtherProperties()
         self::assertSame(Generator::UNDEFINED, $model->properties);
     }
 
-    public function testFormWithRefInSchemaDoNoReadOtherProperties()
+    public function testFormWithRefInSchemaDoNoReadOtherProperties(): void
     {
         $model = $this->getModel('FormWithRefType');
 
@@ -941,7 +945,7 @@ public function testFormCsrfIsOnlyDetectedIfCsrfExtensionIsEnabled(): void
         $this->assertHasProperty('name', $model);
     }
 
-    public function testEntityWithNullableSchemaSet()
+    public function testEntityWithNullableSchemaSet(): void
     {
         $model = $this->getModel('EntityWithNullableSchemaSet');
 
@@ -966,7 +970,7 @@ public function testEntityWithNullableSchemaSet()
         self::assertTrue($model->properties[5]->nullable);
     }
 
-    public function testContextPassedToNameConverter()
+    public function testContextPassedToNameConverter(): void
     {
         $operation = $this->getOperation('/api/name_converter_context', 'get');
 
@@ -1069,7 +1073,7 @@ public function testContextPassedToNameConverter()
         ], json_decode($this->getModel('EntityThroughNameConverterNested2')->toJson(), true));
     }
 
-    public function testArbitraryArrayModel()
+    public function testArbitraryArrayModel(): void
     {
         $this->getOperation('/api/arbitrary_array', 'get');
 
@@ -1105,7 +1109,7 @@ public function testArbitraryArrayModel()
         ], json_decode($this->getModel('Bar')->toJson(), true));
     }
 
-    public function testDictionaryModel()
+    public function testDictionaryModel(): void
     {
         $this->getOperation('/api/dictionary', 'get');
         self::assertEquals([
@@ -1186,7 +1190,7 @@ public function testDictionaryModel()
         ], json_decode($this->getModel('Dictionary')->toJson(), true));
     }
 
-    public function testEntityWithFalsyDefaults()
+    public function testEntityWithFalsyDefaults(): void
     {
         $model = $this->getModel('EntityWithFalsyDefaults');
 
@@ -1228,7 +1232,7 @@ public function testEntityWithFalsyDefaults()
         ], json_decode($model->toJson(), true));
     }
 
-    public function testRangeIntegers()
+    public function testRangeIntegers(): void
     {
         $expected = [
             'schema' => 'RangeInteger',
diff --git a/tests/Functional/JMSFunctionalTest.php b/tests/Functional/JMSFunctionalTest.php
index c97903d71..fb671d3b4 100644
--- a/tests/Functional/JMSFunctionalTest.php
+++ b/tests/Functional/JMSFunctionalTest.php
@@ -22,7 +22,7 @@ protected function setUp(): void
         static::createClient([], ['HTTP_HOST' => 'api.example.com']);
     }
 
-    public function testModelPictureDocumentation()
+    public function testModelPictureDocumentation(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -45,7 +45,7 @@ public function testModelPictureDocumentation()
         ], json_decode($this->getModel('JMSPicture_mini')->toJson(), true));
     }
 
-    public function testModeChatDocumentation()
+    public function testModeChatDocumentation(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -74,7 +74,7 @@ public function testModeChatDocumentation()
         ], json_decode($this->getModel('JMSChatUser')->toJson(), true));
     }
 
-    public function testModelDocumentation()
+    public function testModelDocumentation(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -230,7 +230,7 @@ public function testModelDocumentation()
         ], json_decode($this->getModel('VirtualTypeClassDoesNotExistsHandlerDefined')->toJson(), true));
     }
 
-    public function testModelComplexDualDocumentation()
+    public function testModelComplexDualDocumentation(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -249,7 +249,7 @@ public function testModelComplexDualDocumentation()
         ], json_decode($this->getModel('JMSDualComplex')->toJson(), true));
     }
 
-    public function testNestedGroups()
+    public function testNestedGroups(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -270,7 +270,7 @@ public function testNestedGroups()
         ], json_decode($this->getModel('JMSChatRoom')->toJson(), true));
     }
 
-    public function testModelComplexDocumentation()
+    public function testModelComplexDocumentation(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -289,7 +289,7 @@ public function testModelComplexDocumentation()
         ], json_decode($this->getModel('JMSComplex')->toJson(), true));
     }
 
-    public function testYamlConfig()
+    public function testYamlConfig(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -308,7 +308,7 @@ public function testYamlConfig()
         ], json_decode($this->getModel('VirtualProperty')->toJson(), true));
     }
 
-    public function testNoCollisionsAreGenerated()
+    public function testNoCollisionsAreGenerated(): void
     {
         self::assertFalse($this->hasModel('JMSComplex2'));
         self::assertFalse($this->hasModel('JMSUser2'));
@@ -319,7 +319,7 @@ public function testNoCollisionsAreGenerated()
         self::assertFalse($this->hasModel('JMSPicture2'));
     }
 
-    public function testNamingStrategyWithConstraints()
+    public function testNamingStrategyWithConstraints(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -338,7 +338,7 @@ public function testNamingStrategyWithConstraints()
     /**
      * @requires PHP >= 8.1
      */
-    public function testEnumSupport()
+    public function testEnumSupport(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -372,7 +372,7 @@ public function testEnumSupport()
         ], json_decode($this->getModel('ArticleType81')->toJson(), true));
     }
 
-    public function testModeDiscriminatorMap()
+    public function testModeDiscriminatorMap(): void
     {
         self::assertEquals([
             'type' => 'object',
@@ -413,6 +413,9 @@ public function testModeDiscriminatorMap()
         ], json_decode($this->getModel('JMSAbstractUser')->toJson(), true));
     }
 
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel(TestKernel::USE_JMS);
diff --git a/tests/Functional/ModelDescriber/NameConverter.php b/tests/Functional/ModelDescriber/NameConverter.php
index 5a397d1c8..55502c579 100644
--- a/tests/Functional/ModelDescriber/NameConverter.php
+++ b/tests/Functional/ModelDescriber/NameConverter.php
@@ -28,6 +28,9 @@ public function __construct(MetadataAwareNameConverter $inner)
         $this->inner = $inner;
     }
 
+    /**
+     * @param array<mixed> $context
+     */
     public function normalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         if (!isset($context['secret_name_converter_value'])) {
@@ -37,6 +40,9 @@ public function normalize(string $propertyName, ?string $class = null, ?string $
         return 'name_converter_context_'.$propertyName;
     }
 
+    /**
+     * @param array<mixed> $context
+     */
     public function denormalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         throw new \RuntimeException('Was not expected to be called');
diff --git a/tests/Functional/NelmioKernel.php b/tests/Functional/NelmioKernel.php
index fd73e7dfd..7adf3895f 100644
--- a/tests/Functional/NelmioKernel.php
+++ b/tests/Functional/NelmioKernel.php
@@ -27,14 +27,17 @@ final class NelmioKernel extends Kernel
     /**
      * @var Bundle[]
      */
-    private $extraBundles;
+    private array $extraBundles;
 
+    /**
+     * @var callable|null
+     */
     private $routeConfiguration;
 
     /**
      * @var string[]
      */
-    private $extraConfigs;
+    private array $extraConfigs;
 
     /**
      * @param Bundle[] $extraBundles
@@ -59,14 +62,14 @@ public function registerBundles(): iterable
         return array_merge($bundles, $this->extraBundles);
     }
 
-    protected function configureRoutes(RoutingConfigurator $routes)
+    protected function configureRoutes(RoutingConfigurator $routes): void
     {
         if (null !== $this->routeConfiguration) {
             ($this->routeConfiguration)($routes);
         }
     }
 
-    protected function configureContainer(ContainerBuilder $container, LoaderInterface $loader)
+    protected function configureContainer(ContainerBuilder $container, LoaderInterface $loader): void
     {
         $container->loadFromExtension('framework', ['test' => null]);
 
diff --git a/tests/Functional/SwaggerPHPApiComplianceTest.php b/tests/Functional/SwaggerPHPApiComplianceTest.php
index 177f8e58a..bedb2aa47 100644
--- a/tests/Functional/SwaggerPHPApiComplianceTest.php
+++ b/tests/Functional/SwaggerPHPApiComplianceTest.php
@@ -23,7 +23,7 @@ protected function setUp(): void
         static::createClient([], ['HTTP_HOST' => 'api.example.com']);
     }
 
-    public function testAllContextsCopyRoot()
+    public function testAllContextsCopyRoot(): void
     {
         $openApi = $this->getOpenApiDefinition();
         $root = $openApi->_context;
diff --git a/tests/Functional/SwaggerUiTest.php b/tests/Functional/SwaggerUiTest.php
index e4def2db2..4d462dbc8 100644
--- a/tests/Functional/SwaggerUiTest.php
+++ b/tests/Functional/SwaggerUiTest.php
@@ -29,7 +29,7 @@ protected function setUp(): void
         $this->client = static::createClient([], ['HTTP_HOST' => 'api.example.com', 'PHP_SELF' => '/app_dev.php/default/docs', 'SCRIPT_FILENAME' => '/var/www/app/web/app_dev.php']);
     }
 
-    public function testSwaggerUi()
+    public function testSwaggerUi(): void
     {
         $crawler = $this->client->request('GET', '/app_dev.php/default/docs');
 
@@ -46,7 +46,7 @@ public function testSwaggerUi()
         self::assertEquals($expected, json_decode($crawler->filterXPath('//script[@id="swagger-data"]')->text(), true)['spec']);
     }
 
-    public function testRedocly()
+    public function testRedocly(): void
     {
         $crawler = $this->client->request('GET', '/app_dev.php/default/redocly/docs');
 
@@ -64,7 +64,7 @@ public function testRedocly()
         self::assertEquals($expected, json_decode($crawler->filterXPath('//script[@id="swagger-data"]')->text(), true)['spec']);
     }
 
-    public function testApiPlatformSwaggerUi()
+    public function testApiPlatformSwaggerUi(): void
     {
         $crawler = $this->client->request('GET', '/app_dev.php/test/docs');
 
@@ -80,7 +80,7 @@ public function testApiPlatformSwaggerUi()
         self::assertEquals($expected, json_decode($crawler->filterXPath('//script[@id="swagger-data"]')->text(), true)['spec']);
     }
 
-    public function testJsonDocs()
+    public function testJsonDocs(): void
     {
         $this->client->request('GET', '/app_dev.php/default/docs.json');
 
@@ -96,7 +96,7 @@ public function testJsonDocs()
         self::assertEquals($expected, json_decode($response->getContent(), true));
     }
 
-    public function testInvalidJsonArea()
+    public function testInvalidJsonArea(): void
     {
         $this->client->request('GET', '/app_dev.php/nonexistent/docs.json');
 
@@ -104,7 +104,7 @@ public function testInvalidJsonArea()
         self::assertEquals(400, $response->getStatusCode());
     }
 
-    public function testYamlDocs()
+    public function testYamlDocs(): void
     {
         $this->client->request('GET', '/app_dev.php/default/docs.yaml');
 
diff --git a/tests/Functional/TestKernel.php b/tests/Functional/TestKernel.php
index 2dd48d12b..863792b43 100644
--- a/tests/Functional/TestKernel.php
+++ b/tests/Functional/TestKernel.php
@@ -77,7 +77,7 @@ public function registerBundles(): iterable
         return $bundles;
     }
 
-    protected function configureRoutes(RoutingConfigurator $routes)
+    protected function configureRoutes(RoutingConfigurator $routes): void
     {
         if (self::isAnnotationsAvailable()) {
             $routes->withPath('/')->import(__DIR__.'/Resources/routes.yaml', 'yaml');
@@ -104,7 +104,7 @@ protected function configureRoutes(RoutingConfigurator $routes)
         }
     }
 
-    protected function configureContainer(ContainerBuilder $c, LoaderInterface $loader)
+    protected function configureContainer(ContainerBuilder $c, LoaderInterface $loader): void
     {
         $framework = [
             'assets' => true,
diff --git a/tests/Functional/ValidationGroupsFunctionalTest.php b/tests/Functional/ValidationGroupsFunctionalTest.php
index c7ee31d4a..ad522968b 100644
--- a/tests/Functional/ValidationGroupsFunctionalTest.php
+++ b/tests/Functional/ValidationGroupsFunctionalTest.php
@@ -15,6 +15,9 @@
 
 class ValidationGroupsFunctionalTest extends WebTestCase
 {
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel(TestKernel::USE_VALIDATION_GROUPS);
@@ -27,7 +30,7 @@ protected function setUp(): void
         static::createClient([], ['HTTP_HOST' => 'api.example.com']);
     }
 
-    public function testConstraintGroupsAreRespectedWhenDescribingModels()
+    public function testConstraintGroupsAreRespectedWhenDescribingModels(): void
     {
         $expected = [
             'required' => [
@@ -50,7 +53,7 @@ public function testConstraintGroupsAreRespectedWhenDescribingModels()
         );
     }
 
-    public function testConstraintDefaultGroupsAreRespectedWhenReadingAnnotations()
+    public function testConstraintDefaultGroupsAreRespectedWhenReadingAnnotations(): void
     {
         $expected = [
             'properties' => [
diff --git a/tests/Functional/WebTestCase.php b/tests/Functional/WebTestCase.php
index f932fe0b3..a54d26d50 100644
--- a/tests/Functional/WebTestCase.php
+++ b/tests/Functional/WebTestCase.php
@@ -18,12 +18,15 @@
 
 class WebTestCase extends BaseWebTestCase
 {
+    /**
+     * @param array<mixed> $options
+     */
     protected static function createKernel(array $options = []): KernelInterface
     {
         return new TestKernel();
     }
 
-    protected function getOpenApiDefinition($area = 'default'): OA\OpenApi
+    protected function getOpenApiDefinition(string $area = 'default'): OA\OpenApi
     {
         return static::$kernel->getContainer()->get(sprintf('nelmio_api_doc.generator.%s', $area))->generate();
     }
@@ -36,7 +39,7 @@ public function hasModel(string $name): bool
         return false !== $key;
     }
 
-    protected function getModel($name): OA\Schema
+    protected function getModel(string $name): OA\Schema
     {
         $api = $this->getOpenApiDefinition();
         $key = array_search($name, array_column($api->components->schemas, 'schema'), true);
@@ -45,7 +48,7 @@ protected function getModel($name): OA\Schema
         return $api->components->schemas[$key];
     }
 
-    protected function getOperation($path, $method): OA\Operation
+    protected function getOperation(string $path, string $method): OA\Operation
     {
         $path = $this->getPath($path);
 
@@ -58,6 +61,9 @@ protected function getOperation($path, $method): OA\Operation
         return $path->{$method};
     }
 
+    /**
+     * @param int|string $response
+     */
     protected function getOperationResponse(OA\Operation $operation, $response): OA\Response
     {
         $this->assertHasResponse($response, $operation);
@@ -66,7 +72,7 @@ protected function getOperationResponse(OA\Operation $operation, $response): OA\
         return $operation->responses[$key];
     }
 
-    protected function getProperty(OA\Schema $annotation, $property): OA\Property
+    protected function getProperty(OA\Schema $annotation, string $property): OA\Property
     {
         $this->assertHasProperty($property, $annotation);
         $key = array_search($property, array_column($annotation->properties, 'property'), true);
@@ -77,7 +83,7 @@ protected function getProperty(OA\Schema $annotation, $property): OA\Property
     /**
      * @param OA\Operation|OA\OpenApi $annotation
      */
-    protected function getParameter(OA\AbstractAnnotation $annotation, $name, $in): OA\Parameter
+    protected function getParameter(OA\AbstractAnnotation $annotation, string $name, string $in): OA\Parameter
     {
         $this->assertHasParameter($name, $in, $annotation);
         $parameters = array_filter($annotation->parameters ?? [], function (OA\Parameter $parameter) use ($name, $in) {
@@ -87,7 +93,7 @@ protected function getParameter(OA\AbstractAnnotation $annotation, $name, $in):
         return array_values($parameters)[0];
     }
 
-    protected function getPath($path): OA\PathItem
+    protected function getPath(string $path): OA\PathItem
     {
         $api = $this->getOpenApiDefinition();
         self::assertHasPath($path, $api);
@@ -95,7 +101,7 @@ protected function getPath($path): OA\PathItem
         return $api->paths[array_search($path, array_column($api->paths, 'path'), true)];
     }
 
-    public function assertHasPath($path, OA\OpenApi $api)
+    public function assertHasPath(string $path, OA\OpenApi $api): void
     {
         $paths = array_column(Generator::UNDEFINED !== $api->paths ? $api->paths : [], 'path');
         static::assertContains(
@@ -105,7 +111,7 @@ public function assertHasPath($path, OA\OpenApi $api)
         );
     }
 
-    public function assertNotHasPath($path, OA\OpenApi $api)
+    public function assertNotHasPath(string $path, OA\OpenApi $api): void
     {
         $paths = array_column(Generator::UNDEFINED !== $api->paths ? $api->paths : [], 'path');
         static::assertNotContains(
@@ -115,7 +121,10 @@ public function assertNotHasPath($path, OA\OpenApi $api)
         );
     }
 
-    public function assertHasResponse($responseCode, OA\Operation $operation)
+    /**
+     * @param int|string $responseCode
+     */
+    public function assertHasResponse($responseCode, OA\Operation $operation): void
     {
         $responses = array_column(Generator::UNDEFINED !== $operation->responses ? $operation->responses : [], 'response');
         static::assertContains(
@@ -128,7 +137,7 @@ public function assertHasResponse($responseCode, OA\Operation $operation)
     /**
      * @param OA\Operation|OA\OpenApi $annotation
      */
-    public function assertHasParameter($name, $in, OA\AbstractAnnotation $annotation)
+    public function assertHasParameter(string $name, string $in, OA\AbstractAnnotation $annotation): void
     {
         $parameters = array_filter(Generator::UNDEFINED !== $annotation->parameters ? $annotation->parameters : [], function (OA\Parameter $parameter) use ($name, $in) {
             return $parameter->name === $name && $parameter->in === $in;
@@ -143,7 +152,7 @@ public function assertHasParameter($name, $in, OA\AbstractAnnotation $annotation
     /**
      * @param OA\Operation|OA\OpenApi $annotation
      */
-    public function assertNotHasParameter($name, $in, OA\AbstractAnnotation $annotation)
+    public function assertNotHasParameter(string $name, string $in, OA\AbstractAnnotation $annotation): void
     {
         $parameters = array_column(Generator::UNDEFINED !== $annotation->parameters ? $annotation->parameters : [], 'name', 'in');
         static::assertNotContains(
@@ -156,7 +165,7 @@ public function assertNotHasParameter($name, $in, OA\AbstractAnnotation $annotat
     /**
      * @param OA\Schema|OA\Property|OA\Items $annotation
      */
-    public function assertHasProperty($property, OA\AbstractAnnotation $annotation)
+    public function assertHasProperty(string $property, OA\AbstractAnnotation $annotation): void
     {
         $properties = array_column(Generator::UNDEFINED !== $annotation->properties ? $annotation->properties : [], 'property');
         static::assertContains(
@@ -169,7 +178,7 @@ public function assertHasProperty($property, OA\AbstractAnnotation $annotation)
     /**
      * @param OA\Schema|OA\Property|OA\Items $annotation
      */
-    public function assertNotHasProperty($property, OA\AbstractAnnotation $annotation)
+    public function assertNotHasProperty(string $property, OA\AbstractAnnotation $annotation): void
     {
         $properties = array_column(Generator::UNDEFINED !== $annotation->properties ? $annotation->properties : [], 'property');
         static::assertNotContains(
diff --git a/tests/Model/ModelRegistryTest.php b/tests/Model/ModelRegistryTest.php
index 2c8a53c0b..c6bb4fba5 100644
--- a/tests/Model/ModelRegistryTest.php
+++ b/tests/Model/ModelRegistryTest.php
@@ -21,7 +21,7 @@
 
 class ModelRegistryTest extends TestCase
 {
-    public function testNameAliasingNotAppliedForCollections()
+    public function testNameAliasingNotAppliedForCollections(): void
     {
         $alternativeNames = [
             'Foo1' => [
@@ -37,8 +37,10 @@ public function testNameAliasingNotAppliedForCollections()
 
     /**
      * @dataProvider provideNameCollisionsTypes
+     *
+     * @param array<string, mixed> $arrayType
      */
-    public function testNameCollisionsAreLogged(Type $type, array $arrayType)
+    public function testNameCollisionsAreLogged(Type $type, array $arrayType): void
     {
         $logger = $this->createMock(LoggerInterface::class);
         $logger
@@ -72,7 +74,7 @@ public function testNameCollisionsAreLogged(Type $type, array $arrayType)
         $registry->register(new Model($type, ['group2']));
     }
 
-    public static function provideNameCollisionsTypes(): iterable
+    public static function provideNameCollisionsTypes(): \Generator
     {
         yield [
             new Type(Type::BUILTIN_TYPE_OBJECT, false, self::class),
@@ -108,7 +110,7 @@ public static function provideNameCollisionsTypes(): iterable
         ];
     }
 
-    public function testNameCollisionsAreLoggedWithAlternativeNames()
+    public function testNameCollisionsAreLoggedWithAlternativeNames(): void
     {
         $ref = new \ReflectionClass(self::class);
         $alternativeNames = [
@@ -160,8 +162,11 @@ public function testNameCollisionsAreLoggedWithAlternativeNames()
 
     /**
      * @dataProvider getNameAlternatives
+     *
+     * @param string[]|null        $groups
+     * @param array<string, mixed> $alternativeNames
      */
-    public function testNameAliasingForObjects(string $expected, $groups, array $alternativeNames)
+    public function testNameAliasingForObjects(string $expected, ?array $groups, array $alternativeNames): void
     {
         $registry = new ModelRegistry([], $this->createOpenApi(), $alternativeNames);
         $type = new Type(Type::BUILTIN_TYPE_OBJECT, false, self::class);
@@ -169,57 +174,59 @@ public function testNameAliasingForObjects(string $expected, $groups, array $alt
         self::assertEquals($expected, $registry->register(new Model($type, $groups)));
     }
 
-    public static function getNameAlternatives(): iterable
+    public static function getNameAlternatives(): \Generator
     {
-        return [
+        yield [
+            '#/components/schemas/ModelRegistryTest',
+            null,
             [
-                '#/components/schemas/ModelRegistryTest',
-                null,
-                [
-                    'Foo1' => [
-                        'type' => self::class,
-                        'groups' => ['group1'],
-                    ],
+                'Foo1' => [
+                    'type' => self::class,
+                    'groups' => ['group1'],
                 ],
             ],
+        ];
+
+        yield [
+            '#/components/schemas/Foo1',
+            ['group1'],
             [
-                '#/components/schemas/Foo1',
-                ['group1'],
-                [
-                    'Foo1' => [
-                        'type' => self::class,
-                        'groups' => ['group1'],
-                    ],
+                'Foo1' => [
+                    'type' => self::class,
+                    'groups' => ['group1'],
                 ],
             ],
+        ];
+
+        yield [
+            '#/components/schemas/Foo1',
+            ['group1', 'group2'],
             [
-                '#/components/schemas/Foo1',
-                ['group1', 'group2'],
-                [
-                    'Foo1' => [
-                        'type' => self::class,
-                        'groups' => ['group1', 'group2'],
-                    ],
+                'Foo1' => [
+                    'type' => self::class,
+                    'groups' => ['group1', 'group2'],
                 ],
             ],
+        ];
+
+        yield [
+            '#/components/schemas/ModelRegistryTest',
+            null,
             [
-                '#/components/schemas/ModelRegistryTest',
-                null,
-                [
-                    'Foo1' => [
-                        'type' => self::class,
-                        'groups' => [],
-                    ],
+                'Foo1' => [
+                    'type' => self::class,
+                    'groups' => [],
                 ],
             ],
+        ];
+
+        yield [
+            '#/components/schemas/Foo1',
+            [],
             [
-                '#/components/schemas/Foo1',
-                [],
-                [
-                    'Foo1' => [
-                        'type' => self::class,
-                        'groups' => [],
-                    ],
+                'Foo1' => [
+                    'type' => self::class,
+                    'groups' => [],
                 ],
             ],
         ];
@@ -228,7 +235,7 @@ public static function getNameAlternatives(): iterable
     /**
      * @dataProvider unsupportedTypesProvider
      */
-    public function testUnsupportedTypeException(Type $type, string $stringType)
+    public function testUnsupportedTypeException(Type $type, string $stringType): void
     {
         $this->expectException('\LogicException');
         $this->expectExceptionMessage(sprintf('Schema of type "%s" can\'t be generated, no describer supports it.', $stringType));
@@ -238,15 +245,13 @@ public function testUnsupportedTypeException(Type $type, string $stringType)
         $registry->registerSchemas();
     }
 
-    public static function unsupportedTypesProvider(): iterable
+    public static function unsupportedTypesProvider(): \Generator
     {
-        return [
-            [new Type(Type::BUILTIN_TYPE_ARRAY, false, null, true), 'mixed[]'],
-            [new Type(Type::BUILTIN_TYPE_OBJECT, false, self::class), '\\'.self::class],
-        ];
+        yield [new Type(Type::BUILTIN_TYPE_ARRAY, false, null, true), 'mixed[]'];
+        yield [new Type(Type::BUILTIN_TYPE_OBJECT, false, self::class), '\\'.self::class];
     }
 
-    public function testUnsupportedTypeExceptionWithNonExistentClass()
+    public function testUnsupportedTypeExceptionWithNonExistentClass(): void
     {
         $className = 'Some\\Class\\That\\DoesNotExist';
         $type = new Type(Type::BUILTIN_TYPE_OBJECT, false, $className);
@@ -259,7 +264,7 @@ public function testUnsupportedTypeExceptionWithNonExistentClass()
         $registry->registerSchemas();
     }
 
-    private function createOpenApi()
+    private function createOpenApi(): OA\OpenApi
     {
         return new OA\OpenApi(['_context' => new Context()]);
     }
diff --git a/tests/ModelDescriber/Annotations/AnnotationReaderTest.php b/tests/ModelDescriber/Annotations/AnnotationReaderTest.php
index 4a14f6da9..785670177 100644
--- a/tests/ModelDescriber/Annotations/AnnotationReaderTest.php
+++ b/tests/ModelDescriber/Annotations/AnnotationReaderTest.php
@@ -30,7 +30,7 @@ class AnnotationReaderTest extends TestCase
      *
      * @dataProvider provideProperty
      */
-    public function testProperty($entity)
+    public function testProperty($entity): void
     {
         $baseProps = ['_context' => new Context()];
 
@@ -54,7 +54,7 @@ class_exists(AnnotationReader::class) ? new AnnotationReader() : null,
         self::assertEquals($schema->properties[1]->description, 'some description');
     }
 
-    public static function provideProperty(): iterable
+    public static function provideProperty(): \Generator
     {
         yield 'Annotations' => [new class() {
             /**
diff --git a/tests/ModelDescriber/Annotations/SymfonyConstraintAnnotationReaderTest.php b/tests/ModelDescriber/Annotations/SymfonyConstraintAnnotationReaderTest.php
index b3359e1be..94741734e 100644
--- a/tests/ModelDescriber/Annotations/SymfonyConstraintAnnotationReaderTest.php
+++ b/tests/ModelDescriber/Annotations/SymfonyConstraintAnnotationReaderTest.php
@@ -36,7 +36,7 @@ protected function setUp(): void
         $this->doctrineAnnotations = class_exists(AnnotationReader::class) ? new AnnotationReader() : null;
     }
 
-    public function testUpdatePropertyFix1283()
+    public function testUpdatePropertyFix1283(): void
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             $entity = new class() {
@@ -82,7 +82,7 @@ public function testUpdatePropertyFix1283()
      *
      * @dataProvider provideOptionalProperty
      */
-    public function testOptionalProperty($entity)
+    public function testOptionalProperty($entity): void
     {
         if (!\property_exists(Assert\NotBlank::class, 'allowNull')) {
             self::markTestSkipped('NotBlank::allowNull was added in symfony/validator 4.3.');
@@ -102,7 +102,7 @@ public function testOptionalProperty($entity)
         self::assertEquals($schema->required, ['property2']);
     }
 
-    public static function provideOptionalProperty(): iterable
+    public static function provideOptionalProperty(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -138,7 +138,7 @@ public static function provideOptionalProperty(): iterable
      *
      * @dataProvider provideAssertChoiceResultsInNumericArray
      */
-    public function testAssertChoiceResultsInNumericArray($entity)
+    public function testAssertChoiceResultsInNumericArray($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -152,7 +152,7 @@ public function testAssertChoiceResultsInNumericArray($entity)
         self::assertEquals($schema->properties[0]->enum, ['active', 'blocked']);
     }
 
-    public static function provideAssertChoiceResultsInNumericArray(): iterable
+    public static function provideAssertChoiceResultsInNumericArray(): \Generator
     {
         define('TEST_ASSERT_CHOICE_STATUSES', [
             1 => 'active',
@@ -186,7 +186,7 @@ public static function provideAssertChoiceResultsInNumericArray(): iterable
      *
      * @dataProvider provideMultipleChoiceConstraintsApplyEnumToItems
      */
-    public function testMultipleChoiceConstraintsApplyEnumToItems($entity)
+    public function testMultipleChoiceConstraintsApplyEnumToItems($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -200,7 +200,7 @@ public function testMultipleChoiceConstraintsApplyEnumToItems($entity)
         self::assertEquals($schema->properties[0]->items->enum, ['one', 'two']);
     }
 
-    public static function provideMultipleChoiceConstraintsApplyEnumToItems(): iterable
+    public static function provideMultipleChoiceConstraintsApplyEnumToItems(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [new class() {
@@ -226,7 +226,7 @@ public static function provideMultipleChoiceConstraintsApplyEnumToItems(): itera
      *
      * @dataProvider provideLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet
      */
-    public function testLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet($entity)
+    public function testLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -240,7 +240,7 @@ public function testLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet($entity)
         self::assertSame(1, $schema->properties[0]->minLength);
     }
 
-    public static function provideLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet(): iterable
+    public static function provideLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -268,7 +268,7 @@ public static function provideLengthConstraintDoesNotSetMaxLengthIfMaxIsNotSet()
      *
      * @dataProvider provideLengthConstraintDoesNotSetMinLengthIfMinIsNotSet
      */
-    public function testLengthConstraintDoesNotSetMinLengthIfMinIsNotSet($entity)
+    public function testLengthConstraintDoesNotSetMinLengthIfMinIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -282,7 +282,7 @@ public function testLengthConstraintDoesNotSetMinLengthIfMinIsNotSet($entity)
         self::assertSame(100, $schema->properties[0]->maxLength);
     }
 
-    public static function provideLengthConstraintDoesNotSetMinLengthIfMinIsNotSet(): iterable
+    public static function provideLengthConstraintDoesNotSetMinLengthIfMinIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -303,7 +303,7 @@ public static function provideLengthConstraintDoesNotSetMinLengthIfMinIsNotSet()
         }
     }
 
-    public function testCompoundValidationRules()
+    public function testCompoundValidationRules(): void
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             $entity = new class() {
@@ -350,7 +350,7 @@ public function testCompoundValidationRules()
      *
      * @dataProvider provideCountConstraintDoesNotSetMinItemsIfMinIsNotSet
      */
-    public function testCountConstraintDoesNotSetMinItemsIfMinIsNotSet($entity)
+    public function testCountConstraintDoesNotSetMinItemsIfMinIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -364,7 +364,7 @@ public function testCountConstraintDoesNotSetMinItemsIfMinIsNotSet($entity)
         self::assertSame(10, $schema->properties[0]->maxItems);
     }
 
-    public static function provideCountConstraintDoesNotSetMinItemsIfMinIsNotSet(): iterable
+    public static function provideCountConstraintDoesNotSetMinItemsIfMinIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -392,7 +392,7 @@ public static function provideCountConstraintDoesNotSetMinItemsIfMinIsNotSet():
      *
      * @dataProvider provideCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet
      */
-    public function testCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet($entity)
+    public function testCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -406,7 +406,7 @@ public function testCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet($entity)
         self::assertSame(10, $schema->properties[0]->minItems);
     }
 
-    public static function provideCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet(): iterable
+    public static function provideCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -434,7 +434,7 @@ public static function provideCountConstraintDoesNotSetMaxItemsIfMaxIsNotSet():
      *
      * @dataProvider provideRangeConstraintDoesNotSetMaximumIfMaxIsNotSet
      */
-    public function testRangeConstraintDoesNotSetMaximumIfMaxIsNotSet($entity)
+    public function testRangeConstraintDoesNotSetMaximumIfMaxIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -448,7 +448,7 @@ public function testRangeConstraintDoesNotSetMaximumIfMaxIsNotSet($entity)
         self::assertSame(10, $schema->properties[0]->minimum);
     }
 
-    public static function provideRangeConstraintDoesNotSetMaximumIfMaxIsNotSet(): iterable
+    public static function provideRangeConstraintDoesNotSetMaximumIfMaxIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -476,7 +476,7 @@ public static function provideRangeConstraintDoesNotSetMaximumIfMaxIsNotSet(): i
      *
      * @dataProvider provideRangeConstraintDoesNotSetMinimumIfMinIsNotSet
      */
-    public function testRangeConstraintDoesNotSetMinimumIfMinIsNotSet($entity)
+    public function testRangeConstraintDoesNotSetMinimumIfMinIsNotSet($entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -490,7 +490,7 @@ public function testRangeConstraintDoesNotSetMinimumIfMinIsNotSet($entity)
         self::assertSame(10, $schema->properties[0]->maximum);
     }
 
-    public static function provideRangeConstraintDoesNotSetMinimumIfMinIsNotSet(): iterable
+    public static function provideRangeConstraintDoesNotSetMinimumIfMinIsNotSet(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [
@@ -519,7 +519,7 @@ public static function provideRangeConstraintDoesNotSetMinimumIfMinIsNotSet(): i
      *
      * @dataProvider provideRangeConstraintDoesNotSetMinimumIfMinIsNotSet
      */
-    public function testReaderWithValidationGroupsEnabledChecksForDefaultGroupWhenNoSerializationGroupsArePassed($entity)
+    public function testReaderWithValidationGroupsEnabledChecksForDefaultGroupWhenNoSerializationGroupsArePassed(object $entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([$this->createObj(OA\Property::class, ['property' => 'property1'])]);
@@ -540,7 +540,7 @@ public function testReaderWithValidationGroupsEnabledChecksForDefaultGroupWhenNo
      *
      * @dataProvider provideConstraintsWithGroups
      */
-    public function testReaderWithValidationGroupsEnabledDoesNotReadAnnotationsWithoutDefaultGroupIfNoGroupsArePassed($entity)
+    public function testReaderWithValidationGroupsEnabledDoesNotReadAnnotationsWithoutDefaultGroupIfNoGroupsArePassed(object $entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([
@@ -564,7 +564,7 @@ public function testReaderWithValidationGroupsEnabledDoesNotReadAnnotationsWitho
      *
      * @dataProvider provideConstraintsWithGroups
      */
-    public function testReaderWithValidationGroupsEnabledReadsOnlyConstraintsWithGroupsProvided($entity)
+    public function testReaderWithValidationGroupsEnabledReadsOnlyConstraintsWithGroupsProvided(object $entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([
@@ -589,7 +589,7 @@ public function testReaderWithValidationGroupsEnabledReadsOnlyConstraintsWithGro
      *
      * @dataProvider provideConstraintsWithGroups
      */
-    public function testReaderWithValidationGroupsEnabledCanReadFromMultipleValidationGroups($entity)
+    public function testReaderWithValidationGroupsEnabledCanReadFromMultipleValidationGroups(object $entity): void
     {
         $schema = $this->createObj(OA\Schema::class, []);
         $schema->merge([
@@ -609,7 +609,7 @@ public function testReaderWithValidationGroupsEnabledCanReadFromMultipleValidati
         self::assertSame(1, $schema->properties[0]->minimum, 'should have read constraint in other group');
     }
 
-    public static function provideConstraintsWithGroups(): iterable
+    public static function provideConstraintsWithGroups(): \Generator
     {
         if (interface_exists(Reader::class) && Kernel::MAJOR_VERSION < 7) {
             yield 'Annotations' => [new class() {
@@ -639,7 +639,15 @@ private function createConstraintReaderWithValidationGroupsEnabled(): SymfonyCon
         );
     }
 
-    private function createObj(string $className, array $props = [])
+    /**
+     * @template T of OA\AbstractAnnotation
+     *
+     * @param class-string<T>      $className
+     * @param array<string, mixed> $props
+     *
+     * @return T
+     */
+    private function createObj(string $className, array $props = []): object
     {
         return new $className($props + ['_context' => new Context()]);
     }
diff --git a/tests/ModelDescriber/ApplyOpenApiDiscriminatorTraitTest.php b/tests/ModelDescriber/ApplyOpenApiDiscriminatorTraitTest.php
index cce5d45e7..ec1394a6f 100644
--- a/tests/ModelDescriber/ApplyOpenApiDiscriminatorTraitTest.php
+++ b/tests/ModelDescriber/ApplyOpenApiDiscriminatorTraitTest.php
@@ -27,16 +27,13 @@ class ApplyOpenApiDiscriminatorTraitTest extends TestCase
     public const GROUPS = ['test'];
     public const OPTIONS = ['test' => 123];
 
-    private $schema;
+    private OA\Schema $schema;
 
-    private $model;
+    private Model $model;
 
-    /**
-     * @var ModelRegistry
-     */
-    private $modelRegistry;
+    private ModelRegistry $modelRegistry;
 
-    public function testApplyAddsDiscriminatorProperty()
+    public function testApplyAddsDiscriminatorProperty(): void
     {
         $this->applyOpenApiDiscriminator($this->model, $this->schema, $this->modelRegistry, 'type', [
             'one' => 'FirstType',
@@ -57,7 +54,7 @@ public function testApplyAddsDiscriminatorProperty()
         );
     }
 
-    public function testApplyAddsOneOfFieldToSchema()
+    public function testApplyAddsOneOfFieldToSchema(): void
     {
         $this->applyOpenApiDiscriminator($this->model, $this->schema, $this->modelRegistry, 'type', [
             'one' => 'FirstType',
diff --git a/tests/ModelDescriber/FormModelDescriberTest.php b/tests/ModelDescriber/FormModelDescriberTest.php
index 4ce1cb818..e1a1b81f2 100644
--- a/tests/ModelDescriber/FormModelDescriberTest.php
+++ b/tests/ModelDescriber/FormModelDescriberTest.php
@@ -80,13 +80,11 @@ public function testDescribeCreatesTokenPropertyDependingOnOptions(bool $csrfPro
         }
     }
 
-    public static function provideCsrfProtectionOptions(): iterable
+    public static function provideCsrfProtectionOptions(): \Generator
     {
-        return [
-            [true, '_token', true],
-            [true, '_another_token', true],
-            [false, '_token', false],
-        ];
+        yield [true, '_token', true];
+        yield [true, '_another_token', true];
+        yield [false, '_token', false];
     }
 
     private function initSchema(): \OpenApi\Annotations\Schema
diff --git a/tests/ModelDescriber/SelfDescribingModelDescriberTest.php b/tests/ModelDescriber/SelfDescribingModelDescriberTest.php
index 102045b9b..b9fbdaf89 100644
--- a/tests/ModelDescriber/SelfDescribingModelDescriberTest.php
+++ b/tests/ModelDescriber/SelfDescribingModelDescriberTest.php
@@ -20,21 +20,21 @@
 
 class SelfDescribingModelDescriberTest extends TestCase
 {
-    public function testSupports()
+    public function testSupports(): void
     {
         $describer = new SelfDescribingModelDescriber();
 
         self::assertTrue($describer->supports(new Model(new Type('object', false, SelfDescribingModel::class))));
     }
 
-    public function testDoesNotSupport()
+    public function testDoesNotSupport(): void
     {
         $describer = new SelfDescribingModelDescriber();
 
         self::assertFalse($describer->supports(new Model(new Type('object', false, \stdClass::class))));
     }
 
-    public function testDescribe()
+    public function testDescribe(): void
     {
         $describer = new SelfDescribingModelDescriber();
 
diff --git a/tests/Render/Html/GetNelmioAssetTest.php b/tests/Render/Html/GetNelmioAssetTest.php
index 1dcf54940..990f88e7c 100644
--- a/tests/Render/Html/GetNelmioAssetTest.php
+++ b/tests/Render/Html/GetNelmioAssetTest.php
@@ -17,8 +17,15 @@
 
 class GetNelmioAssetTest extends WebTestCase
 {
-    /** @dataProvider provideAsset */
-    public function test($mode, $asset, $expectedContent)
+    private const CDN_DIR = 'https://cdn.jsdelivr.net/gh/nelmio/NelmioApiDocBundle/public';
+    private const RESOURCE_DIR = __DIR__.'/../../../public';
+
+    /**
+     * @dataProvider provideCss
+     * @dataProvider provideJs
+     * @dataProvider provideImage
+     */
+    public function test(string $mode, string $asset, string $expectedContent): void
     {
         static::bootKernel();
         /** @var GetNelmioAsset $getNelmioAsset */
@@ -30,86 +37,70 @@ public function test($mode, $asset, $expectedContent)
         self::assertSame($expectedContent, $twigFunction->getCallable()->__invoke($mode, $asset));
     }
 
-    public static function provideAsset(): iterable
+    public static function provideCss(): \Generator
     {
-        $cdnDir = 'https://cdn.jsdelivr.net/gh/nelmio/NelmioApiDocBundle/public';
-        $resourceDir = __DIR__.'/../../../public';
-
-        return self::provideCss($cdnDir, $resourceDir)
-            + self::provideJs($cdnDir, $resourceDir)
-            + self::provideImage($cdnDir);
-    }
-
-    private static function provideCss($cdnDir, $resourceDir): array
-    {
-        return [
-            'bundled css' => [
-                AssetsMode::BUNDLE,
-                'style.css',
-                '<link rel="stylesheet" href="/bundles/nelmioapidoc/style.css">',
-            ],
-            'cdn css' => [
-                AssetsMode::CDN,
-                'style.css',
-                '<link rel="stylesheet" href="'.$cdnDir.'/style.css">',
-            ],
-            'offline css' => [
-                AssetsMode::OFFLINE,
-                'style.css',
-                '<style>'.file_get_contents($resourceDir.'/style.css').'</style>',
-            ],
-            'external css' => [
-                AssetsMode::BUNDLE,
-                'https://cdn.com/my.css',
-                '<link rel="stylesheet" href="https://cdn.com/my.css">',
-            ],
+        yield 'bundled css' => [
+            AssetsMode::BUNDLE,
+            'style.css',
+            '<link rel="stylesheet" href="/bundles/nelmioapidoc/style.css">',
+        ];
+        yield 'cdn css' => [
+            AssetsMode::CDN,
+            'style.css',
+            '<link rel="stylesheet" href="'.self::CDN_DIR.'/style.css">',
+        ];
+        yield 'offline css' => [
+            AssetsMode::OFFLINE,
+            'style.css',
+            '<style>'.file_get_contents(self::RESOURCE_DIR.'/style.css').'</style>',
+        ];
+        yield 'external css' => [
+            AssetsMode::BUNDLE,
+            'https://cdn.com/my.css',
+            '<link rel="stylesheet" href="https://cdn.com/my.css">',
         ];
     }
 
-    private static function provideJs($cdnDir, $resourceDir): array
+    public static function provideJs(): \Generator
     {
-        return [
-            'bundled js' => [
-                AssetsMode::BUNDLE,
-                'init-swagger-ui.js',
-                '<script src="/bundles/nelmioapidoc/init-swagger-ui.js"></script>',
-            ],
-            'cdn js' => [
-                AssetsMode::CDN,
-                'init-swagger-ui.js',
-                '<script src="'.$cdnDir.'/init-swagger-ui.js"></script>',
-            ],
-            'offline js' => [
-                AssetsMode::OFFLINE,
-                'init-swagger-ui.js',
-                '<script>'.file_get_contents($resourceDir.'/init-swagger-ui.js').'</script>',
-            ],
-            'external js' => [
-                AssetsMode::BUNDLE,
-                'https://cdn.com/my.js',
-                '<script src="https://cdn.com/my.js"></script>',
-            ],
+        yield 'bundled js' => [
+            AssetsMode::BUNDLE,
+            'init-swagger-ui.js',
+            '<script src="/bundles/nelmioapidoc/init-swagger-ui.js"></script>',
+        ];
+        yield 'cdn js' => [
+            AssetsMode::CDN,
+            'init-swagger-ui.js',
+            '<script src="'.self::CDN_DIR.'/init-swagger-ui.js"></script>',
+        ];
+        yield 'offline js' => [
+            AssetsMode::OFFLINE,
+            'init-swagger-ui.js',
+            '<script>'.file_get_contents(self::RESOURCE_DIR.'/init-swagger-ui.js').'</script>',
+        ];
+        yield 'external js' => [
+            AssetsMode::BUNDLE,
+            'https://cdn.com/my.js',
+            '<script src="https://cdn.com/my.js"></script>',
         ];
     }
 
-    private static function provideImage($cdnDir): array
+    public static function provideImage(): \Generator
     {
-        return [
-            'bundled image' => [
-                AssetsMode::BUNDLE,
-                'logo.png',
-                '/bundles/nelmioapidoc/logo.png',
-            ],
-            'cdn image' => [
-                AssetsMode::CDN,
-                'logo.png',
-                $cdnDir.'/logo.png',
-            ],
-            'offline image fallbacks to cdn' => [
-                AssetsMode::OFFLINE,
-                'logo.png',
-                $cdnDir.'/logo.png',
-            ],
+        yield 'bundled image' => [
+            AssetsMode::BUNDLE,
+            'logo.png',
+            '/bundles/nelmioapidoc/logo.png',
+        ];
+        yield 'cdn image' => [
+            AssetsMode::CDN,
+            'logo.png',
+            self::CDN_DIR.'/logo.png',
+        ];
+        yield 'offline image fallbacks to cdn' => [
+            AssetsMode::OFFLINE,
+            'logo.png',
+            self::CDN_DIR.'/logo.png',
         ];
     }
 }
diff --git a/tests/Render/RenderOpenApiTest.php b/tests/Render/RenderOpenApiTest.php
index 5e259abf7..b9bcda55c 100644
--- a/tests/Render/RenderOpenApiTest.php
+++ b/tests/Render/RenderOpenApiTest.php
@@ -19,36 +19,36 @@
 
 class RenderOpenApiTest extends TestCase
 {
-    private $area = 'irrelevant area';
-    private $format = 'irrelevant format';
-    private $hasArea = true;
+    private const AREA = 'irrelevant area';
+    private const FORMAT = 'irrelevant format';
+    private bool $hasArea = true;
 
-    public function testRender()
+    public function testRender(): void
     {
         $openApiRenderer = $this->createMock(OpenApiRenderer::class);
-        $openApiRenderer->method('getFormat')->willReturn($this->format);
+        $openApiRenderer->method('getFormat')->willReturn(self::FORMAT);
         $openApiRenderer->expects(self::once())->method('render');
         $this->renderOpenApi($openApiRenderer);
     }
 
-    public function testUnknownFormat()
+    public function testUnknownFormat(): void
     {
         $availableOpenApiRenderers = [];
-        $this->expectExceptionObject(new \InvalidArgumentException(sprintf('Format "%s" is not supported.', $this->format)));
+        $this->expectExceptionObject(new \InvalidArgumentException(sprintf('Format "%s" is not supported.', self::FORMAT)));
         $this->renderOpenApi(...$availableOpenApiRenderers);
     }
 
-    public function testUnknownArea()
+    public function testUnknownArea(): void
     {
         $this->hasArea = false;
-        $this->expectExceptionObject(new \InvalidArgumentException(sprintf('Area "%s" is not supported.', $this->area)));
+        $this->expectExceptionObject(new \InvalidArgumentException(sprintf('Area "%s" is not supported.', self::AREA)));
         $this->renderOpenApi();
     }
 
-    public function testNullFormat()
+    public function testNullFormat(): void
     {
         $openApiRenderer = $this->createMock(OpenApiRenderer::class);
-        $openApiRenderer->method('getFormat')->willReturn($this->format);
+        $openApiRenderer->method('getFormat')->willReturn(self::FORMAT);
         $openApiRenderer->expects(self::once())->method('render');
 
         $availableOpenApiRenderers = [
@@ -58,18 +58,18 @@ public function testNullFormat()
         $this->renderOpenApi(...$availableOpenApiRenderers);
     }
 
-    private function renderOpenApi(...$openApiRenderer): void
+    private function renderOpenApi(?OpenApiRenderer ...$openApiRenderer): void
     {
         $spec = $this->createMock(OpenApi::class);
         $generator = new class($spec) {
-            private $spec;
+            private OpenApi $spec;
 
-            public function __construct($spec)
+            public function __construct(OpenApi $spec)
             {
                 $this->spec = $spec;
             }
 
-            public function generate()
+            public function generate(): OpenApi
             {
                 return $this->spec;
             }
@@ -80,6 +80,6 @@ public function generate()
         $generatorLocator->method('get')->willReturn($generator);
 
         $renderOpenApi = new RenderOpenApi($generatorLocator, ...$openApiRenderer);
-        $renderOpenApi->render($this->format, $this->area, []);
+        $renderOpenApi->render(self::FORMAT, self::AREA, []);
     }
 }
diff --git a/tests/RouteDescriber/FosRestDescriberTest.php b/tests/RouteDescriber/FosRestDescriberTest.php
index 6770d6096..51da37a65 100644
--- a/tests/RouteDescriber/FosRestDescriberTest.php
+++ b/tests/RouteDescriber/FosRestDescriberTest.php
@@ -21,7 +21,7 @@
 
 class FosRestDescriberTest extends TestCase
 {
-    public function testQueryParamWithChoiceConstraintIsAddedAsEnum()
+    public function testQueryParamWithChoiceConstraintIsAddedAsEnum(): void
     {
         $choices = ['foo', 'bar'];
 
diff --git a/tests/RouteDescriber/RouteMetadataDescriberTest.php b/tests/RouteDescriber/RouteMetadataDescriberTest.php
index 81e09a4c9..03027a557 100644
--- a/tests/RouteDescriber/RouteMetadataDescriberTest.php
+++ b/tests/RouteDescriber/RouteMetadataDescriberTest.php
@@ -20,14 +20,16 @@
 
 class RouteMetadataDescriberTest extends TestCase
 {
-    public function testUndefinedCheck()
+    public function testUndefinedCheck(): void
     {
+        self::expectNotToPerformAssertions();
+
         $routeDescriber = new RouteMetadataDescriber();
 
-        self::assertNull($routeDescriber->describe(new OpenApi(['_context' => new Context()]), new Route('foo'), new \ReflectionMethod(__CLASS__, 'testUndefinedCheck')));
+        $routeDescriber->describe(new OpenApi(['_context' => new Context()]), new Route('foo'), new \ReflectionMethod(__CLASS__, 'testUndefinedCheck'));
     }
 
-    public function testRouteRequirementsWithPattern()
+    public function testRouteRequirementsWithPattern(): void
     {
         $api = new OpenApi([]);
         $routeDescriber = new RouteMetadataDescriber();
@@ -38,20 +40,20 @@ public function testRouteRequirementsWithPattern()
             new \ReflectionMethod(__CLASS__, 'testRouteRequirementsWithPattern')
         );
 
-        self::assertEquals('/index/{bar}/{foo}.html', $api->paths[0]->path);
+        self::assertSame('/index/{bar}/{foo}.html', $api->paths[0]->path);
         $getPathParameter = $api->paths[0]->get->parameters[1];
         if ('foo' === $getPathParameter->name) {
-            self::assertEquals('path', $getPathParameter->in);
-            self::assertEquals('foo', $getPathParameter->name);
-            self::assertEquals('string', $getPathParameter->schema->type);
-            self::assertEquals('[0-9]|[a-z]', $getPathParameter->schema->pattern);
+            self::assertSame('path', $getPathParameter->in);
+            self::assertSame('foo', $getPathParameter->name);
+            self::assertSame('string', $getPathParameter->schema->type);
+            self::assertSame('[0-9]|[a-z]', $getPathParameter->schema->pattern);
         }
     }
 
     /**
      * @dataProvider provideEnumPattern
      */
-    public function testSimpleOrRequirementsAreHandledAsEnums($req)
+    public function testSimpleOrRequirementsAreHandledAsEnums(string $req): void
     {
         $api = new OpenApi([]);
         $routeDescriber = new RouteMetadataDescriber();
@@ -62,19 +64,19 @@ public function testSimpleOrRequirementsAreHandledAsEnums($req)
             new \ReflectionMethod(__CLASS__, 'testSimpleOrRequirementsAreHandledAsEnums')
         );
 
-        self::assertEquals('/index/{bar}/{foo}.html', $api->paths[0]->path);
+        self::assertSame('/index/{bar}/{foo}.html', $api->paths[0]->path);
         $getPathParameter = $api->paths[0]->get->parameters[1];
-        self::assertEquals('path', $getPathParameter->in);
-        self::assertEquals('foo', $getPathParameter->name);
-        self::assertEquals('string', $getPathParameter->schema->type);
-        self::assertEquals(explode('|', $req), $getPathParameter->schema->enum);
-        self::assertEquals($req, $getPathParameter->schema->pattern);
+        self::assertSame('path', $getPathParameter->in);
+        self::assertSame('foo', $getPathParameter->name);
+        self::assertSame('string', $getPathParameter->schema->type);
+        self::assertSame(explode('|', $req), $getPathParameter->schema->enum);
+        self::assertSame($req, $getPathParameter->schema->pattern);
     }
 
     /**
      * @dataProvider provideInvalidEnumPattern
      */
-    public function testNonEnumPatterns($pattern)
+    public function testNonEnumPatterns(string $pattern): void
     {
         $api = new OpenApi([]);
         $routeDescriber = new RouteMetadataDescriber();
@@ -86,11 +88,11 @@ public function testNonEnumPatterns($pattern)
         );
 
         $getPathParameter = $api->paths[0]->get->parameters[0];
-        self::assertEquals($pattern, $getPathParameter->schema->pattern);
-        self::assertEquals(Generator::UNDEFINED, $getPathParameter->schema->enum);
+        self::assertSame($pattern, $getPathParameter->schema->pattern);
+        self::assertSame(Generator::UNDEFINED, $getPathParameter->schema->enum);
     }
 
-    public static function provideEnumPattern(): iterable
+    public static function provideEnumPattern(): \Generator
     {
         yield ['1|2|3'];
         yield ['srf|rtr|rsi'];
@@ -98,7 +100,7 @@ public static function provideEnumPattern(): iterable
         yield ['srf-1|srf-2'];
     }
 
-    public static function provideInvalidEnumPattern(): iterable
+    public static function provideInvalidEnumPattern(): \Generator
     {
         yield ['|'];
         yield ['|a'];
diff --git a/tests/Routing/FilteredRouteCollectionBuilderTest.php b/tests/Routing/FilteredRouteCollectionBuilderTest.php
index 9bc1d102b..fa30bafde 100644
--- a/tests/Routing/FilteredRouteCollectionBuilderTest.php
+++ b/tests/Routing/FilteredRouteCollectionBuilderTest.php
@@ -40,7 +40,7 @@ protected function setUp(): void
         $this->doctrineAnnotations = class_exists(AnnotationReader::class) ? new AnnotationReader() : null;
     }
 
-    public function testFilter()
+    public function testFilter(): void
     {
         $options = [
             'path_patterns' => [
@@ -74,7 +74,7 @@ public function testFilter()
      *
      * @expectedDeprecation Passing an indexed array with a collection of path patterns as argument 1 for `Nelmio\ApiDocBundle\Routing\FilteredRouteCollectionBuilder::__construct()` is deprecated since 3.2.0, expected structure is an array containing parameterized options.
      */
-    public function testFilterWithDeprecatedArgument()
+    public function testFilterWithDeprecatedArgument(): void
     {
         $pathPattern = [
             '^/api/foo',
@@ -99,8 +99,10 @@ public function testFilterWithDeprecatedArgument()
 
     /**
      * @dataProvider getInvalidOptions
+     *
+     * @param array<string, mixed> $options
      */
-    public function testFilterWithInvalidOption(array $options)
+    public function testFilterWithInvalidOption(array $options): void
     {
         $this->expectException(InvalidArgumentException::class);
 
@@ -112,27 +114,28 @@ public function testFilterWithInvalidOption(array $options)
         );
     }
 
-    public static function getInvalidOptions(): iterable
+    public static function getInvalidOptions(): \Generator
     {
-        return [
-            [['invalid_option' => null]],
-            [['invalid_option' => 42]],
-            [['invalid_option' => []]],
-            [['path_patterns' => [22]]],
-            [['path_patterns' => [null]]],
-            [['path_patterns' => [new \stdClass()]]],
-            [['path_patterns' => ['^/foo$', 1]]],
-            [['with_annotation' => ['an array']]],
-            [['path_patterns' => 'a string']],
-            [['path_patterns' => 11]],
-            [['name_patterns' => 22]],
-            [['name_patterns' => 'a string']],
-            [['name_patterns' => [22]]],
-            [['name_patterns' => [null]]],
-            [['name_patterns' => [new \stdClass()]]],
-        ];
+        yield [['invalid_option' => null]];
+        yield [['invalid_option' => 42]];
+        yield [['invalid_option' => []]];
+        yield [['path_patterns' => [22]]];
+        yield [['path_patterns' => [null]]];
+        yield [['path_patterns' => [new \stdClass()]]];
+        yield [['path_patterns' => ['^/foo$', 1]]];
+        yield [['with_annotation' => ['an array']]];
+        yield [['path_patterns' => 'a string']];
+        yield [['path_patterns' => 11]];
+        yield [['name_patterns' => 22]];
+        yield [['name_patterns' => 'a string']];
+        yield [['name_patterns' => [22]]];
+        yield [['name_patterns' => [null]]];
+        yield [['name_patterns' => [new \stdClass()]]];
     }
 
+    /**
+     * @return array<string,Route>
+     */
     private function getRoutes(): array
     {
         return [
@@ -151,8 +154,10 @@ private function getRoutes(): array
 
     /**
      * @dataProvider getMatchingRoutes
+     *
+     * @param array<string, mixed> $options
      */
-    public function testMatchingRoutes(string $name, Route $route, array $options = [])
+    public function testMatchingRoutes(string $name, Route $route, array $options = []): void
     {
         $routes = new RouteCollection();
         $routes->add($name, $route);
@@ -168,7 +173,7 @@ public function testMatchingRoutes(string $name, Route $route, array $options =
         self::assertCount(1, $filteredRoutes);
     }
 
-    public static function getMatchingRoutes(): iterable
+    public static function getMatchingRoutes(): \Generator
     {
         yield from [
             ['r1', new Route('/api/bar/action1')],
@@ -188,8 +193,10 @@ public static function getMatchingRoutes(): iterable
      * @group test
      *
      * @dataProvider getMatchingRoutesWithAnnotation
+     *
+     * @param array<string, mixed> $options
      */
-    public function testMatchingRoutesWithAnnotation(string $name, Route $route, array $options = [])
+    public function testMatchingRoutesWithAnnotation(string $name, Route $route, array $options = []): void
     {
         $routes = new RouteCollection();
         $routes->add($name, $route);
@@ -220,7 +227,7 @@ public function testMatchingRoutesWithAnnotation(string $name, Route $route, arr
         self::assertCount(1, $filteredRoutes);
     }
 
-    public static function getMatchingRoutesWithAnnotation(): iterable
+    public static function getMatchingRoutesWithAnnotation(): \Generator
     {
         yield from [
             'with annotation only' => [
@@ -253,8 +260,10 @@ public static function getMatchingRoutesWithAnnotation(): iterable
 
     /**
      * @dataProvider getNonMatchingRoutes
+     *
+     * @param array<string, mixed> $options
      */
-    public function testNonMatchingRoutes(string $name, Route $route, array $options = [])
+    public function testNonMatchingRoutes(string $name, Route $route, array $options = []): void
     {
         $routes = new RouteCollection();
         $routes->add($name, $route);
@@ -270,16 +279,14 @@ public function testNonMatchingRoutes(string $name, Route $route, array $options
         self::assertCount(0, $filteredRoutes);
     }
 
-    public static function getNonMatchingRoutes(): iterable
+    public static function getNonMatchingRoutes(): \Generator
     {
-        return [
-            ['r1', new Route('/api/bar/action1'), ['path_patterns' => ['^/apis']]],
-            ['r2', new Route('/api/foo/action1'), ['path_patterns' => ['^/apis', 'i/foo/b', 'n1/$'], 'name_patterns' => ['r2']]],
-            ['r3_matching_path_and_non_matching_host', new Route('/api/foo/action2'), ['path_patterns' => ['^/api/foo/action2$'], 'host_patterns' => ['^api\.']]],
-            ['r4_matching_path_and_non_matching_host', new Route('/api/bar/action1', [], [], [], 'www.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.']]],
-            ['r5_non_matching_path_and_matching_host', new Route('/admin/bar/action1', [], [], [], 'api.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.']]],
-            ['r6_non_matching_path_and_non_matching_host', new Route('/admin/bar/action1', [], [], [], 'www.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.ex']]],
-        ];
+        yield ['r1', new Route('/api/bar/action1'), ['path_patterns' => ['^/apis']]];
+        yield ['r2', new Route('/api/foo/action1'), ['path_patterns' => ['^/apis', 'i/foo/b', 'n1/$'], 'name_patterns' => ['r2']]];
+        yield ['r3_matching_path_and_non_matching_host', new Route('/api/foo/action2'), ['path_patterns' => ['^/api/foo/action2$'], 'host_patterns' => ['^api\.']]];
+        yield ['r4_matching_path_and_non_matching_host', new Route('/api/bar/action1', [], [], [], 'www.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.']]];
+        yield ['r5_non_matching_path_and_matching_host', new Route('/admin/bar/action1', [], [], [], 'api.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.']]];
+        yield ['r6_non_matching_path_and_non_matching_host', new Route('/admin/bar/action1', [], [], [], 'www.example.com'), ['path_patterns' => ['^/api/'], 'host_patterns' => ['^api\.ex']]];
     }
 
     /**
@@ -323,33 +330,28 @@ public function testRoutesWithDisabledDefaultRoutes(
         self::assertCount($expectedRoutesCount, $filteredRoutes);
     }
 
-    /**
-     * @return array<string,array>
-     */
-    public static function getRoutesWithDisabledDefaultRoutes(): iterable
+    public static function getRoutesWithDisabledDefaultRoutes(): \Generator
     {
-        return [
-            'non matching route without Annotation' => [
-                'r10',
-                new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
-                [],
-                ['disable_default_routes' => true],
-                0,
-            ],
-            'matching route with Nelmio Annotation' => [
-                'r10',
-                new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
-                [new Operation(['_context' => new Context()])],
-                ['disable_default_routes' => true],
-                1,
-            ],
-            'matching route with Swagger Annotation' => [
-                'r10',
-                new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
-                [new Parameter(['_context' => new Context()])],
-                ['disable_default_routes' => true],
-                1,
-            ],
+        yield 'non matching route without Annotation' => [
+            'r10',
+            new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
+            [],
+            ['disable_default_routes' => true],
+            0,
+        ];
+        yield 'matching route with Nelmio Annotation' => [
+            'r10',
+            new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
+            [new Operation(['_context' => new Context()])],
+            ['disable_default_routes' => true],
+            1,
+        ];
+        yield 'matching route with Swagger Annotation' => [
+            'r10',
+            new Route('/api/foo', ['_controller' => 'ApiController::fooAction']),
+            [new Parameter(['_context' => new Context()])],
+            ['disable_default_routes' => true],
+            1,
         ];
     }
 
diff --git a/tests/SwaggerPhp/UtilTest.php b/tests/SwaggerPhp/UtilTest.php
index ff550f7d7..f45699059 100644
--- a/tests/SwaggerPhp/UtilTest.php
+++ b/tests/SwaggerPhp/UtilTest.php
@@ -41,10 +41,9 @@
  */
 class UtilTest extends TestCase
 {
-    public $rootContext;
+    private Context $rootContext;
 
-    /** @var OA\OpenApi */
-    public $rootAnnotation;
+    private OA\OpenApi $rootAnnotation;
 
     public function setUp(): void
     {
@@ -66,14 +65,14 @@ public function tearDown(): void
         restore_error_handler();
     }
 
-    public function testCreateContextSetsParentContext()
+    public function testCreateContextSetsParentContext(): void
     {
         $context = Util::createContext([], $this->rootContext);
 
         $this->assertContextIsConnectedToRootContext($context);
     }
 
-    public function testCreateContextWithProperties()
+    public function testCreateContextWithProperties(): void
     {
         $context = Util::createContext(['testing' => 'trait']);
 
@@ -81,21 +80,21 @@ public function testCreateContextWithProperties()
         self::assertSame('trait', $context->testing);
     }
 
-    public function testCreateChild()
+    public function testCreateChild(): void
     {
         $info = Util::createChild($this->rootAnnotation, OA\Info::class);
 
         self::assertInstanceOf(OA\Info::class, $info);
     }
 
-    public function testCreateChildHasContext()
+    public function testCreateChildHasContext(): void
     {
         $info = Util::createChild($this->rootAnnotation, OA\Info::class);
 
         self::assertInstanceOf(Context::class, $info->_context);
     }
 
-    public function testCreateChildHasNestedContext()
+    public function testCreateChildHasNestedContext(): void
     {
         $path = Util::createChild($this->rootAnnotation, OA\PathItem::class);
         $this->assertIsNested($this->rootAnnotation, $path);
@@ -109,7 +108,7 @@ public function testCreateChildHasNestedContext()
         $this->assertIsConnectedToRootContext($schema);
     }
 
-    public function testCreateChildWithEmptyProperties()
+    public function testCreateChildWithEmptyProperties(): void
     {
         $properties = [];
         /** @var OA\Info $info */
@@ -125,7 +124,7 @@ public function testCreateChildWithEmptyProperties()
         $this->assertIsConnectedToRootContext($info);
     }
 
-    public function testCreateChildWithProperties()
+    public function testCreateChildWithProperties(): void
     {
         $properties = ['title' => 'testing', 'version' => '999', 'x' => new \stdClass()];
         /** @var OA\Info $info */
@@ -139,7 +138,7 @@ public function testCreateChildWithProperties()
         $this->assertIsConnectedToRootContext($info);
     }
 
-    public function testCreateCollectionItemAddsCreatedItemToCollection()
+    public function testCreateCollectionItemAddsCreatedItemToCollection(): void
     {
         $collection = 'paths';
         $class = OA\PathItem::class;
@@ -171,7 +170,7 @@ public function testCreateCollectionItemAddsCreatedItemToCollection()
         $this->assertIsConnectedToRootContext($this->rootAnnotation->components->{$collection}[$d1]);
     }
 
-    public function testCreateCollectionItemDoesNotAddToUnknownProperty()
+    public function testCreateCollectionItemDoesNotAddToUnknownProperty(): void
     {
         $collection = 'foobars';
         $class = OA\Info::class;
@@ -185,7 +184,7 @@ public function testCreateCollectionItemDoesNotAddToUnknownProperty()
         self::assertNull($this->rootAnnotation->{$collection}); /* @phpstan-ignore-line */
     }
 
-    public function testSearchCollectionItem()
+    public function testSearchCollectionItem(): void
     {
         $item1 = new \stdClass();
         $item1->prop1 = 'item 1 prop 1';
@@ -222,8 +221,11 @@ public function testSearchCollectionItem()
 
     /**
      * @dataProvider provideIndexedCollectionData
+     *
+     * @param array<mixed> $setup
+     * @param array<mixed> $asserts
      */
-    public function testSearchIndexedCollectionItem($setup, $asserts)
+    public function testSearchIndexedCollectionItem(array $setup, array $asserts): void
     {
         foreach ($asserts as $collection => $items) {
             foreach ($items as $assert) {
@@ -253,8 +255,11 @@ public function testSearchIndexedCollectionItem($setup, $asserts)
 
     /**
      * @dataProvider provideIndexedCollectionData
+     *
+     * @param array<mixed> $setup
+     * @param array<mixed> $asserts
      */
-    public function testGetIndexedCollectionItem($setup, $asserts)
+    public function testGetIndexedCollectionItem(array $setup, array $asserts): void
     {
         $parent = new $setup['class'](array_merge(
             $this->getSetupPropertiesWithoutClass($setup),
@@ -265,6 +270,7 @@ public function testGetIndexedCollectionItem($setup, $asserts)
             foreach ($items as $assert) {
                 $itemParent = !isset($assert['components']) ? $parent : $parent->components;
 
+                self::assertTrue(is_a($assert['class'], OA\AbstractAnnotation::class, true), sprintf('Invalid class %s', $assert['class']));
                 $child = Util::getIndexedCollectionItem(
                     $itemParent,
                     $assert['class'],
@@ -291,9 +297,9 @@ public function testGetIndexedCollectionItem($setup, $asserts)
         }
     }
 
-    public static function provideIndexedCollectionData(): iterable
+    public static function provideIndexedCollectionData(): \Generator
     {
-        return [[
+        yield [
             'setup' => [
                 'class' => OA\OpenApi::class,
                 'paths' => [
@@ -374,13 +380,16 @@ public static function provideIndexedCollectionData(): iterable
                     ],
                 ],
             ],
-        ]];
+        ];
     }
 
     /**
      * @dataProvider provideChildData
+     *
+     * @param array<mixed> $setup
+     * @param array<mixed> $asserts
      */
-    public function testGetChild($setup, $asserts)
+    public function testGetChild(array $setup, array $asserts): void
     {
         $parent = new $setup['class'](array_merge(
             $this->getSetupPropertiesWithoutClass($setup),
@@ -391,6 +400,7 @@ public function testGetChild($setup, $asserts)
             if (\array_key_exists('exceptionMessage', $assert)) {
                 $this->expectExceptionMessage($assert['exceptionMessage']);
             }
+            self::assertTrue(is_a($assert['class'], OA\AbstractAnnotation::class, true), sprintf('Invalid class %s', $assert['class']));
             $child = Util::getChild($parent, $assert['class'], $assert['props']);
 
             self::assertInstanceOf($assert['class'], $child);
@@ -404,9 +414,9 @@ public function testGetChild($setup, $asserts)
         }
     }
 
-    public static function provideChildData(): iterable
+    public static function provideChildData(): \Generator
     {
-        return [[
+        yield [
             'setup' => [
                 'class' => OA\PathItem::class,
                 'get' => self::createObj(OA\Get::class, []),
@@ -431,7 +441,9 @@ public static function provideChildData(): iterable
                     ],
                 ],
             ],
-        ], [
+        ];
+
+        yield [
             'setup' => [
                 'class' => OA\Parameter::class,
             ],
@@ -446,7 +458,9 @@ public static function provideChildData(): iterable
                     ],
                 ],
             ],
-        ], [
+        ];
+
+        yield [
             'setup' => [
                 'class' => OA\Parameter::class,
             ],
@@ -460,10 +474,10 @@ public static function provideChildData(): iterable
                     'exceptionMessage' => 'Nesting Annotations is not supported.',
                 ],
             ],
-        ]];
+        ];
     }
 
-    public function testGetOperationParameterReturnsExisting()
+    public function testGetOperationParameterReturnsExisting(): void
     {
         $name = 'operation name';
         $in = 'operation in';
@@ -482,7 +496,7 @@ public function testGetOperationParameterReturnsExisting()
         self::assertSame($parameter, $actual);
     }
 
-    public function testGetOperationParameterCreatesWithNameAndIn()
+    public function testGetOperationParameterCreatesWithNameAndIn(): void
     {
         $name = 'operation name';
         $in = 'operation in';
@@ -500,7 +514,7 @@ public function testGetOperationParameterCreatesWithNameAndIn()
         self::assertSame($in, $actual->in);
     }
 
-    public function testGetOperationReturnsExisting()
+    public function testGetOperationReturnsExisting(): void
     {
         $get = self::createObj(OA\Get::class, []);
         $path = self::createObj(OA\PathItem::class, ['get' => $get]);
@@ -508,7 +522,7 @@ public function testGetOperationReturnsExisting()
         self::assertSame($get, Util::getOperation($path, 'get'));
     }
 
-    public function testGetOperationCreatesWithPath()
+    public function testGetOperationCreatesWithPath(): void
     {
         $pathStr = '/testing/get/path';
         $path = self::createObj(OA\PathItem::class, ['path' => $pathStr]);
@@ -518,7 +532,7 @@ public function testGetOperationCreatesWithPath()
         self::assertSame($pathStr, $get->path);
     }
 
-    public function testMergeWithEmptyArray()
+    public function testMergeWithEmptyArray(): void
     {
         $api = self::createObj(OA\OpenApi::class, ['_context' => new Context()]);
         $expected = json_encode($api);
@@ -536,8 +550,12 @@ public function testMergeWithEmptyArray()
 
     /**
      * @dataProvider provideMergeData
+     *
+     * @param array<mixed>              $setup
+     * @param array<mixed>|\ArrayObject $merge
+     * @param array<mixed>              $assert
      */
-    public function testMerge($setup, $merge, $assert)
+    public function testMerge(array $setup, $merge, array $assert): void
     {
         $api = self::createObj(OA\OpenApi::class, $setup + ['_context' => new Context()]);
 
@@ -548,7 +566,7 @@ public function testMerge($setup, $merge, $assert)
         self::assertEquals($assert, $actual);
     }
 
-    public static function provideMergeData(): array
+    public static function provideMergeData(): \Generator
     {
         $no = 'do not overwrite';
         $yes = 'do overwrite';
@@ -565,7 +583,7 @@ public static function provideMergeData(): array
             'paths' => [],
         ];
 
-        return [[
+        yield [
             // simple child merge
             'setup' => [
                 'info' => self::createObj(OA\Info::class, ['version' => $no]),
@@ -577,7 +595,9 @@ public static function provideMergeData(): array
             'assert' => [
                 'info' => ['title' => $yes, 'version' => $no],
             ] + $assertDefaults,
-        ], [
+        ];
+
+        yield [
             // Parse server url with variables, see https://github.com/nelmio/NelmioApiDocBundle/issues/1691
             'setup' => $setupDefaults,
             'merge' => [
@@ -596,7 +616,9 @@ public static function provideMergeData(): array
                     ],
                 ],
             ] + $assertDefaults,
-        ], [
+        ];
+
+        yield [
             // indexed collection merge
             'setup' => [
                 'components' => self::createObj(OA\Components::class, [
@@ -619,7 +641,9 @@ public static function provideMergeData(): array
                     ],
                 ],
             ] + $assertDefaults,
-        ], [
+        ];
+
+        yield [
             // collection merge
             'setup' => [
                 'tags' => [self::createObj(OA\Tag::class, ['name' => $no])],
@@ -645,56 +669,56 @@ public static function provideMergeData(): array
                     ['name' => $no, 'description' => $yes],
                 ],
             ] + $assertDefaults,
-        ],
-            [
-                // heavy nested merge array
-                'setup' => $setupDefaults,
-                'merge' => $merge = [
-                    'servers' => [
-                        ['url' => 'http'],
-                        ['url' => 'https'],
-                    ],
-                    'paths' => [
-                        '/path/to/resource' => [
-                            'get' => [
-                                'responses' => [
-                                    '200' => [
-                                        '$ref' => '#/components/responses/default',
-                                    ],
+        ];
+
+        yield [
+            // heavy nested merge array
+            'setup' => $setupDefaults,
+            'merge' => $merge = [
+                'servers' => [
+                    ['url' => 'http'],
+                    ['url' => 'https'],
+                ],
+                'paths' => [
+                    '/path/to/resource' => [
+                        'get' => [
+                            'responses' => [
+                                '200' => [
+                                    '$ref' => '#/components/responses/default',
                                 ],
-                                'requestBody' => [
-                                    'description' => 'request foo',
-                                    'content' => [
-                                        'foo-request' => [
-                                            'schema' => [
-                                                'type' => 'object',
-                                                'required' => ['baz', 'bar'],
-                                            ],
+                            ],
+                            'requestBody' => [
+                                'description' => 'request foo',
+                                'content' => [
+                                    'foo-request' => [
+                                        'schema' => [
+                                            'type' => 'object',
+                                            'required' => ['baz', 'bar'],
                                         ],
                                     ],
                                 ],
                             ],
                         ],
                     ],
-                    'tags' => [
-                        ['name' => 'baz'],
-                        ['name' => 'foo'],
-                        ['name' => 'baz'],
-                        ['name' => 'foo'],
-                        ['name' => 'foo'],
-                    ],
-                    'components' => [
-                        'responses' => [
-                            'default' => [
-                                'description' => 'default response',
-                                'headers' => [
-                                    'foo-header' => [
-                                        'schema' => [
-                                            'type' => 'array',
-                                            'items' => [
-                                                'type' => 'string',
-                                                'enum' => ['foo', 'bar', 'baz'],
-                                            ],
+                ],
+                'tags' => [
+                    ['name' => 'baz'],
+                    ['name' => 'foo'],
+                    ['name' => 'baz'],
+                    ['name' => 'foo'],
+                    ['name' => 'foo'],
+                ],
+                'components' => [
+                    'responses' => [
+                        'default' => [
+                            'description' => 'default response',
+                            'headers' => [
+                                'foo-header' => [
+                                    'schema' => [
+                                        'type' => 'array',
+                                        'items' => [
+                                            'type' => 'string',
+                                            'enum' => ['foo', 'bar', 'baz'],
                                         ],
                                     ],
                                 ],
@@ -702,163 +726,176 @@ public static function provideMergeData(): array
                         ],
                     ],
                 ],
-                'assert' => array_merge(
-                    $assertDefaults,
-                    $merge,
-                    ['tags' => \array_slice($merge['tags'], 0, 2, true)]
-                ),
-            ], [
-                // heavy nested merge array object
-                'setup' => $setupDefaults,
-                'merge' => new \ArrayObject([
-                    'servers' => [
-                        ['url' => 'http'],
-                        ['url' => 'https'],
-                    ],
-                    'paths' => [
-                        '/path/to/resource' => [
-                            'get' => new \ArrayObject([
-                                'responses' => [
-                                    '200' => [
-                                        '$ref' => '#/components/responses/default',
-                                    ],
+            ],
+            'assert' => array_merge(
+                $assertDefaults,
+                $merge,
+                ['tags' => \array_slice($merge['tags'], 0, 2, true)]
+            ),
+        ];
+
+        yield [
+            // heavy nested merge array object
+            'setup' => $setupDefaults,
+            'merge' => new \ArrayObject([
+                'servers' => [
+                    ['url' => 'http'],
+                    ['url' => 'https'],
+                ],
+                'paths' => [
+                    '/path/to/resource' => [
+                        'get' => new \ArrayObject([
+                            'responses' => [
+                                '200' => [
+                                    '$ref' => '#/components/responses/default',
                                 ],
-                                'requestBody' => new \ArrayObject([
-                                    'description' => 'request foo',
-                                    'content' => [
-                                        'foo-request' => [
-                                            'schema' => [
-                                                'required' => ['baz', 'bar'],
-                                                'type' => 'object',
-                                            ],
+                            ],
+                            'requestBody' => new \ArrayObject([
+                                'description' => 'request foo',
+                                'content' => [
+                                    'foo-request' => [
+                                        'schema' => [
+                                            'required' => ['baz', 'bar'],
+                                            'type' => 'object',
                                         ],
                                     ],
-                                ]),
+                                ],
                             ]),
-                        ],
+                        ]),
                     ],
-                    'tags' => new \ArrayObject([
-                        ['name' => 'baz'],
-                        ['name' => 'foo'],
-                        new \ArrayObject(['name' => 'baz']),
-                        ['name' => 'foo'],
-                        ['name' => 'foo'],
-                    ]),
-                    'components' => new \ArrayObject([
-                        'responses' => [
-                            'default' => [
-                                'description' => 'default response',
-                                'headers' => new \ArrayObject([
-                                    'foo-header' => new \ArrayObject([
-                                        'schema' => new \ArrayObject([
-                                            'type' => 'array',
-                                            'items' => new \ArrayObject([
-                                                'type' => 'string',
-                                                'enum' => ['foo', 'bar', 'baz'],
-                                            ]),
+                ],
+                'tags' => new \ArrayObject([
+                    ['name' => 'baz'],
+                    ['name' => 'foo'],
+                    new \ArrayObject(['name' => 'baz']),
+                    ['name' => 'foo'],
+                    ['name' => 'foo'],
+                ]),
+                'components' => new \ArrayObject([
+                    'responses' => [
+                        'default' => [
+                            'description' => 'default response',
+                            'headers' => new \ArrayObject([
+                                'foo-header' => new \ArrayObject([
+                                    'schema' => new \ArrayObject([
+                                        'type' => 'array',
+                                        'items' => new \ArrayObject([
+                                            'type' => 'string',
+                                            'enum' => ['foo', 'bar', 'baz'],
                                         ]),
                                     ]),
                                 ]),
-                            ],
+                            ]),
                         ],
-                    ]),
-                ]),
-                'assert' => array_merge(
-                    $assertDefaults,
-                    $merge,
-                    ['tags' => \array_slice($merge['tags'], 0, 2, true)]
-                ),
-            ], [
-                // heavy nested merge swagger instance
-                'setup' => $setupDefaults,
-                'merge' => self::createObj(OA\OpenApi::class, [
-                    'servers' => [
-                        self::createObj(OA\Server::class, ['url' => 'http']),
-                        self::createObj(OA\Server::class, ['url' => 'https']),
                     ],
-                    'paths' => [
-                        self::createObj(OA\PathItem::class, [
-                            'path' => '/path/to/resource',
-                            'get' => self::createObj(OA\Get::class, [
-                                'responses' => [
-                                    self::createObj(OA\Response::class, [
-                                        'response' => '200',
-                                        'ref' => '#/components/responses/default',
-                                    ]),
-                                ],
-                                'requestBody' => self::createObj(OA\RequestBody::class, [
-                                    'description' => 'request foo',
-                                    'content' => [
-                                        self::createObj(OA\MediaType::class, [
-                                            'mediaType' => 'foo-request',
-                                            'schema' => self::createObj(OA\Schema::class, [
-                                                'type' => 'object',
-                                                'required' => ['baz', 'bar'],
-                                            ]),
-                                        ]),
-                                    ],
+                ]),
+            ]),
+            'assert' => array_merge(
+                $assertDefaults,
+                $merge,
+                ['tags' => \array_slice($merge['tags'], 0, 2, true)]
+            ),
+        ];
+
+        yield [
+            // heavy nested merge swagger instance
+            'setup' => $setupDefaults,
+            'merge' => self::createObj(OA\OpenApi::class, [
+                'servers' => [
+                    self::createObj(OA\Server::class, ['url' => 'http']),
+                    self::createObj(OA\Server::class, ['url' => 'https']),
+                ],
+                'paths' => [
+                    self::createObj(OA\PathItem::class, [
+                        'path' => '/path/to/resource',
+                        'get' => self::createObj(OA\Get::class, [
+                            'responses' => [
+                                self::createObj(OA\Response::class, [
+                                    'response' => '200',
+                                    'ref' => '#/components/responses/default',
                                 ]),
-                            ]),
-                        ]),
-                    ],
-                    'tags' => [
-                        self::createObj(OA\Tag::class, ['name' => 'baz']),
-                        self::createObj(OA\Tag::class, ['name' => 'foo']),
-                        self::createObj(OA\Tag::class, ['name' => 'baz']),
-                        self::createObj(OA\Tag::class, ['name' => 'foo']),
-                        self::createObj(OA\Tag::class, ['name' => 'foo']),
-                    ],
-                    'components' => self::createObj(OA\Components::class, [
-                        'responses' => [
-                            self::createObj(OA\Response::class, [
-                                'response' => 'default',
-                                'description' => 'default response',
-                                'headers' => [
-                                    self::createObj(OA\Header::class, [
-                                        'header' => 'foo-header',
+                            ],
+                            'requestBody' => self::createObj(OA\RequestBody::class, [
+                                'description' => 'request foo',
+                                'content' => [
+                                    self::createObj(OA\MediaType::class, [
+                                        'mediaType' => 'foo-request',
                                         'schema' => self::createObj(OA\Schema::class, [
-                                            'type' => 'array',
-                                            'items' => self::createObj(OA\Items::class, [
-                                                'type' => 'string',
-                                                'enum' => ['foo', 'bar', 'baz'],
-                                            ]),
+                                            'type' => 'object',
+                                            'required' => ['baz', 'bar'],
                                         ]),
                                     ]),
                                 ],
                             ]),
-                        ],
+                        ]),
                     ]),
+                ],
+                'tags' => [
+                    self::createObj(OA\Tag::class, ['name' => 'baz']),
+                    self::createObj(OA\Tag::class, ['name' => 'foo']),
+                    self::createObj(OA\Tag::class, ['name' => 'baz']),
+                    self::createObj(OA\Tag::class, ['name' => 'foo']),
+                    self::createObj(OA\Tag::class, ['name' => 'foo']),
+                ],
+                'components' => self::createObj(OA\Components::class, [
+                    'responses' => [
+                        self::createObj(OA\Response::class, [
+                            'response' => 'default',
+                            'description' => 'default response',
+                            'headers' => [
+                                self::createObj(OA\Header::class, [
+                                    'header' => 'foo-header',
+                                    'schema' => self::createObj(OA\Schema::class, [
+                                        'type' => 'array',
+                                        'items' => self::createObj(OA\Items::class, [
+                                            'type' => 'string',
+                                            'enum' => ['foo', 'bar', 'baz'],
+                                        ]),
+                                    ]),
+                                ]),
+                            ],
+                        ]),
+                    ],
                 ]),
-                'assert' => array_merge(
-                    $assertDefaults,
-                    $merge,
-                    ['tags' => \array_slice($merge['tags'], 0, 2, true)]
-                ),
-            ], ];
+            ]),
+            'assert' => array_merge(
+                $assertDefaults,
+                $merge,
+                ['tags' => \array_slice($merge['tags'], 0, 2, true)]
+            ),
+        ];
     }
 
-    public function assertIsNested(OA\AbstractAnnotation $parent, OA\AbstractAnnotation $child)
+    public function assertIsNested(OA\AbstractAnnotation $parent, OA\AbstractAnnotation $child): void
     {
         self::assertTrue($child->_context->is('nested'));
         self::assertSame($parent, $child->_context->nested);
     }
 
-    public function assertIsConnectedToRootContext(OA\AbstractAnnotation $annotation)
+    public function assertIsConnectedToRootContext(OA\AbstractAnnotation $annotation): void
     {
         $this->assertContextIsConnectedToRootContext($annotation->_context);
     }
 
-    public function assertContextIsConnectedToRootContext(Context $context)
+    public function assertContextIsConnectedToRootContext(Context $context): void
     {
         self::assertSame($this->rootContext, $context->root());
     }
 
-    private function getSetupPropertiesWithoutClass(array $setup)
+    /**
+     * @param array<mixed> $setup
+     *
+     * @return array<mixed>
+     */
+    private function getSetupPropertiesWithoutClass(array $setup): array
     {
         return array_filter($setup, function ($k) {return 'class' !== $k; }, ARRAY_FILTER_USE_KEY);
     }
 
-    private function getNonDefaultProperties($object)
+    /**
+     * @return array<mixed>
+     */
+    private function getNonDefaultProperties(OA\AbstractAnnotation $object): array
     {
         $objectVars = \get_object_vars($object);
         $classVars = \get_class_vars(\get_class($object));
@@ -872,7 +909,11 @@ private function getNonDefaultProperties($object)
         return $props;
     }
 
-    private static function createObj(string $className, array $props = [])
+    /**
+     * @param class-string<OA\AbstractAnnotation> $className
+     * @param array<string, mixed>                $props
+     */
+    private static function createObj(string $className, array $props = []): object
     {
         return new $className($props + ['_context' => new Context()]);
     }