How can I tweak zsh's completion system to complete “fake” files in some circumstances?
More precisely, the AVFS filesystem exposes archives as directories by creating a “fake directory” next to every archive. By default, it replicates the whole directory hierarchy under its mount point ~/.avfs. Furthermore, under ~/.avfs, for every archive file such as /tmp/foo.zip, besides the archive file itself ~/.avfs/tmp/foo.zip, there is a directory called ~/.avfs/tmp/foo.zip# which exposes the content of the archive. However this extra directory does not appear in the listing of ~/.avfs/tmp: it only exists when explicitly requested. (This is similar to how some automounters operate.)
mountavfs
cd ~/.avfs/tmp/foo.zip\#
When I type a command like the one above, foo.zip# doesn't appear as a completion under ~/.avfs/tmp/, since there is no such directory. How can I tell zsh that whenever there is a file whose full path $arc matches ~/.avfs/**/*.(tgz|zip)¹, it should pretend that there is a directory called ${arc}#?
(Note that I want the completion to work with every call to _files or _dirs, not just for the cd command. I'd prefer not to have to duplicate the code of the _files function, if possible.)
¹ and all the rest of the extensions
