Exception in pure PHP

Fatal error: Uncaught Nette\MemberAccessException: Call to undefined method Nette\Application\UI\Form::addTest()? in /sandbox/vendor/nette/utils/src/Utils/ObjectMixin.php:100 Stack trace: #0 /sandbox/vendor/nette/utils/src/Utils/Object.php(75): Nette\Utils\ObjectMixin::call(Object(Nette\Application\UI\Form), 'addTest', Array) #1 /sandbox/app/forms/SignFormFactory.php(32): Nette\Object->__call('addTest', Array) #2 /sandbox/app/presenters/SignPresenter.php(21): App\Forms\SignFormFactory->create() #3 /sandbox/vendor/nette/component-model/src/ComponentModel/Container.php(181): App\Presenters\SignPresenter->createComponentSignInForm('signInForm') #4 /sandbox/vendor/nette/component-model/src/ComponentModel/Container.php(139): Nette\ComponentModel\Container->createComponent('signInForm') #5 /sandbox/temp/cache/latte/x-sandbox-app-presenters-templates-Sign-in-latte-Template53adebb15206b353f351f6bfca2c36cc.php(17): Nette\ComponentModel\Co in /sandbox/vendor/nette/utils/src/Utils/ObjectMixin.php on line 100