I am currently upgrading a project to use phpstan to better catch type errors, @template and class-string have been particularly helpfull

However, I have a method on the projects router, that takes two string parameters for a controller action.

Those parameters map to a controller class name, and method, eg:

    /**
     * @param class-string<Controller> $controllerName
     * @param string $methodName
     * @return Route
     */
     public function toController(string $controllerName, string $methodName) : Route

I can tell phpstan that the first parameter $controllerName must be a class name, and a subtype of Controller.
However the $methodName param is currently just an untyped string.

I would like to be able to say it must be a public method on the class $className, but cannot find anything in the docs, or google searching.

I did find key-of<Type::ARRAY_CONST> which seems close, but works on const arrays.

Does anything exist to handle this at present?