Re: rm can accidentally delete dirs

   rm *f t*    should delete '-rf' and the  test file,
   leaving the directory, however, it interperates -rf as
   arguments, deleteing the folder and its contents. (It
   also leaves the -rf file).

Not a bug.  Wildcards get expanded by the shell, thus what you are
typing (i.e. what the shell is seeing) is "rm -rf testdir".  So to be
sure that you want to delete the directory -rf to, type "rm -- *f", or
some such.