silverstripe-widgets/tests/WidgetControllerTestPage.php

<?php
/**
 * @package cms
 * @subpackage tests
 */
class WidgetControllerTestPage extends Page implements TestOnly
{
    private static $has_one = array(
        'WidgetControllerTestSidebar' => 'WidgetArea'
    );
}

/**
 * @package cms
 * @subpackage tests
 */
class WidgetControllerTestPage_Controller extends Page_Controller implements TestOnly
{
    /**
     * Template selection doesnt work in test folders,
     * so we enforce a template name.
     */
    public function getViewer($action)
    {
        $templates = array('WidgetControllerTestPage');
        
        return new SSViewer($templates);
    }
}