bug#2654: ispell-complete-word fails

[Glenn Morris]

emacs -Q

Type "foo", followed by M-x ispell-complete-word:

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  looking-at(nil)
  ispell-get-word(nil "\\*")
  ispell-complete-word(nil)
  call-interactively(ispell-complete-word t nil)
  execute-extended-command(nil)
  call-interactively(execute-extended-command nil nil)

This happens because in ispell-get-word

(if (not (looking-at ispell-casechars))

has ispell-casechars = nil. This is because (ispell-get-casechars)
returns nil; and this is because ispell-dictionary-alist is now nil by
default.