Devise\Pages\Fields\FieldValue::toJSON PHP Метод

    public function toJSON()
    {
        return $this->json;
    }

 public function test_it_merges_data()
 {
     $obj = new FieldValue('{}');
     $obj->merge(['one' => 'two', 'buckle' => 'my shoe']);
     assertEquals('{"one":"two","buckle":"my shoe"}', $obj->toJSON());
 }