GraphQL\Type\Definition\Type::string PHP Метод

    public static function string()
    {
        return self::getInternalType(self::STRING);
    }

 public function setUp()
 {
     $NamedType = new InterfaceType(['name' => 'Named', 'fields' => ['name' => ['type' => Type::string()]]]);
     $DogType = new ObjectType(['name' => 'Dog', 'interfaces' => [$NamedType], 'fields' => ['name' => ['type' => Type::string()], 'barks' => ['type' => Type::boolean()]], 'isTypeOf' => function ($value) {
         return $value instanceof Dog;
     }]);
     $CatType = new ObjectType(['name' => 'Cat', 'interfaces' => [$NamedType], 'fields' => ['name' => ['type' => Type::string()], 'meows' => ['type' => Type::boolean()]], 'isTypeOf' => function ($value) {
         return $value instanceof Cat;
     }]);
     $PetType = new UnionType(['name' => 'Pet', 'types' => [$DogType, $CatType], 'resolveType' => function ($value) use($DogType, $CatType) {
         if ($value instanceof Dog) {
             return $DogType;
         }
         if ($value instanceof Cat) {
             return $CatType;
         }
     }]);
     $PersonType = new ObjectType(['name' => 'Person', 'interfaces' => [$NamedType], 'fields' => ['name' => ['type' => Type::string()], 'pets' => ['type' => Type::listOf($PetType)], 'friends' => ['type' => Type::listOf($NamedType)]], 'isTypeOf' => function ($value) {
         return $value instanceof Person;
     }]);
     $this->schema = new Schema($PersonType);
     $this->garfield = new Cat('Garfield', false);
     $this->odie = new Dog('Odie', true);
     $this->liz = new Person('Liz');
     $this->john = new Person('John', [$this->garfield, $this->odie], [$this->liz, $this->odie]);
 }