User configurable controller factory

This is related to DI (dependency injection) but I want to make it clear up front that I am not just talking about DI i.e. this is not a duplicate of https://forum.codeigniter.com/thread-61345.html et al.

This is a subtly different feature request as implementing a user-configurable controller factory would permit end-users to implement DI differently if they wanted to do so.

In CodeIgniter\CodeIgniter::createController() (framework/system/CodeIgniter.php) controllers are instantiated with the new keyword. If this was extracted to a factory class (perhaps resolvable via the Services configuration file) then end-users would be able to manage dependency injection for their controllers.

A quick example implementation:

PHP Code:

  /**
     * In app/Config/Services.php
     * @param string $requestedName
     * @return object
     */
    public static function controllerFactory($requestedName)
    {
        return new $requestedName;
    } 


With CodeIgniter\CodeIgniter::createController() altered to call this user-configurable factory:

PHP Code:

    /**
     * Instantiates the controller class.
     *
     * @return mixed
     */
    protected function createController()
    {
        $class = Services::controllerFactory($this->controller);
        $class->initController($this->request, $this->response, Services::logger());

        $this->benchmark->stop('controller_constructor');

        return $class;
    } 


So far this would work exactly the same as the current controller instantiation but the instantiation has been moved into user space allowing end-users to instantiate controllers differently. An alternative implementation of the controllerFactory service might look like this:

PHP Code:

    /**
     * In app/Config/Services.php
     * @param string $requestedName
     * @return object
     */
    public static function controllerFactory($requestedName)
    {
        if(is_subclass_of($requestedName, \App\Controllers\CustomBaseController::class)) {
            return new $requestedName(static::getSharedInstance('example'));
        }

        return new $requestedName;
    } 


Or it could be quite different. The point being that it is user-configurable. Thoughts?