TOC - SITEMAP - `$toc.url` check breaking

[gsalunke]

In the sitemap, if an entry does not have a URL specified, the toc.url is supposed to be null.

We are using below check whether $toc.url is present or not and if $toc.url is null we are not including link: $toc.url into our FTD files.

--- ftd.text:
if: $toc.url is not null
link: $toc.url

But we observed toc.link is always present, even when the URL is not present in sitemap.