Dynamic menu-items in Custom Menu widget

Hi,

I’m on WP 4.4 running with a Twentysixteen child theme. I’m displaying a custom menu in my sidebar using the Custom Menu widget. I want to show a menu item only for Authors, Editors & Administrators in the menu. To do this, I have added a function in my child theme’s functions.php. The code for this function is as follows…

function add_dynamic_link ($items, $args) {
	if (current_user_can ('publish_posts')) {
		if ($args->menu == 'Sidebar') {
			$items .= '<li><a href="/teamspace">Teamspace</a></li>';
		}
	}
	return $items;
}

add_filter ('wp_nav_menu_items', 'add_dynamic_link', 10, 2);

However, this does not have the desired result. The menu remains unchanged. I tried debugging the function by adding the following line of code at different points in the function.

echo $items;

From the debugging process, I could gather that the filter is being executed. The problem seems to be that the execution flow is not entering the following “IF” construct…

if ($args->menu == 'Sidebar') {
			$items .= '<li><a href="/teamspace">Teamspace</a></li>';
		}

Now, there exists a custom menu called Sidebar on my install. So this should not be happening. I tried changing the $args properties being validated. Instead of $args->menu == ‘Sidebar’ I tried using $args->menu == ‘menu-sidebar’ (the ID of the custom menu) as well as $args->container_class == ‘menu-sidebar-container’ but none of them works.

If I remove the problematic “IF” construct, the menu item shows in all the active menus on the site…not only the one in the widget.

What could I be doing wrong and how do I rectify it?

Thanks