class HelpPageTestHooks

class HelpPageTestHooks {
    
    /**
     * Implements hook_help().
     */
    public function help($route_name, RouteMatchInterface $route_match) {
        switch ($route_name) {
            case 'help.page.help_page_test':
                // Make the help text conform to core standards. See
                // \Drupal\system\Tests\Functional\GenericModuleTestBase::assertHookHelp().
                return t('Read the <a href=":url">online documentation for the Help Page Test module</a>.', [
                    ':url' => 'http://www.example.com',
                ]);
            case 'help_page_test.has_help':
                return t('I have help!');
            case 'help_page_test.test_array':
                return [
                    '#markup' => 'Help text from help_page_test_help module.',
                ];
        }
        // Ensure that hook_help() can return an empty string and not cause the block
        // to display.
        return '';
    }

}