Currently the ControllerTrait::render and ControllerTrait::renderView methods assume that when the templating service is available it can always render the given view via that service.

However, that might not be the case. For example if framework.templating is not configured to support the twig engine for example but only some other custom engine, e.g.

framework:
  templating:
    engines: 
      - foobar

it will fail when the given view references a Twig template for instance and the configured engine cannot render that.

The Symfony\Component\Templating\EngineInterface which templating implements defines a support method:

which should be used here, in order to make sure that templating actually does support rendering the given view.