upd

src/VkProvider.php

@@ -144,10 +144,12 @@ class VkProvider extends AbstractProvider
 
         return $url;
     }
-    protected function getDefaultScopes()
+    
+    protected function getDefaultScopes(): array
     {
         return $this->scopes;
     }
+
     protected function checkResponse(ResponseInterface $response, $data): void
     {
         // Metadata info

src/VkUser.php

@@ -35,7 +35,7 @@ class VkUser implements ResourceOwnerInterface
     /**
      * Helper for getting user data
      */
-    protected function getField(string $key): mixed|null
+    protected function getField(string $key): mixed
     {
         return !empty($this->response[$key]) ? $this->response[$key] : null;
     }
@@ -67,12 +67,12 @@ class VkUser implements ResourceOwnerInterface
     /**
      * Short address to user page
      */
-    public function getDomain(): string
+    public function getDomain(): string|null
     {
         return $this->getField('domain');
     }
     
-    public function getFirstName(): string
+    public function getFirstName(): string|null
     {
         return $this->getField('first_name');
     }
@@ -93,7 +93,7 @@ class VkUser implements ResourceOwnerInterface
         return (bool)$this->getField('has_photo');
     }
     
-    public function getHomeTown(): string
+    public function getHomeTown(): string|null
     {
         return $this->getField('home_town');
     }
@@ -106,17 +106,17 @@ class VkUser implements ResourceOwnerInterface
         return (bool)$this->getField('is_friend');
     }
     
-    public function getLastName(): string
+    public function getLastName(): string|null
     {
         return $this->getField('last_name');
     }
 
-    public function getMaidenName(): string
+    public function getMaidenName(): string|null
     {
         return $this->getField('maiden_name');
     }
 
-    public function getNickname(): string
+    public function getNickname(): string|null
     {
         return $this->getField('nickname');
     }
@@ -128,12 +128,12 @@ class VkUser implements ResourceOwnerInterface
         return $this->getField('photo_max');
     }
 
-    public function getPhotoMaxOrig(): string
+    public function getPhotoMaxOrig(): string|null
     {
         return $this->getField('photo_max_orig');
     }
     
-    public function getScreenName(): string
+    public function getScreenName(): string|null
     {
         return $this->getField('screen_name');
     }
@@ -143,7 +143,7 @@ class VkUser implements ResourceOwnerInterface
         return $this->getField('sex');
     }
 
-    public function getEmail(): string
+    public function getEmail(): string|null
     {
         return $this->getField('email');
     }