If a package has RESTRICT=fetch, the instructions typically tell me to go off and download the files, then put them into $DISTDIR. Unfortunately, if this happens during --ask or --pretend, $DISTDIR might not exist! It’s only created when Portage starts actually fetching files. This is reasonably trivial to work around (just create $DISTDIR myself), but it would be nice if Portage created it for me before telling me to put things in it (consider, for example, that I might create it with the wrong permissions if I do it myself).