bug#20581: 24.5; aspell dictionary de-alt not found

[Felix E. Klee]

On Fri, May 15, 2015 at 11:01 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> So could you please step in Edebug through the code in ispell.el […]

As said before, `ispell-dictionary-alist` is assembled from the output
of `aspell dicts`. For each line in the output,
`ispell-aspell-find-dictionary` is called. Example:

    ELISP> (ispell-aspell-find-dictionary "de_DE")
    ("de_DE" "[[:alpha:]]" "[^[:alpha:]]" "" t
     ("-d" "de_DE")
     nil utf-8)

It doesn’t work with `de-alt`:

    ELISP> (ispell-aspell-find-dictionary "de-alt")
    nil

I used `edebug` on `ispell-aspell-find-dictionary` and found that there
is pattern matching happening that strips the variant `alt` from
`de-alt`. Then a path is assembled, `fullpath`, which evaluates to:
"/usr/lib/aspell-0.60/de.dat"

That `.dat` file doesn’t exist. For `de-alt` it is a mistake to strip
the variant. The correct path is: "/usr/lib/aspell-0.60/de-alt.dat"