Well you must be typing the PHP inside a *.php file, so .inc won't work, plus I noticed that it only gives you code hints for super globals.
So whenever you type $_ it will give you a choice of COOKIE, ENV, GET, PUT, SESSION, SERVER, etc.
Remember too, that PHP (unlike simple HTML) has over 700 functions - so it would have been a mountain of a task (which would need to be constantly updated) to provide code hints for all of those.
