bug#52179: Highlighting a word in `ispell' using `enchant'

[Eli Zaretskii]

> From: Tor Kringeland <tor.a.s.kringeland@ntnu.no>
> Cc: 52179@debbugs.gnu.org
> Date: Mon, 29 Nov 2021 21:46:05 +0100
> 
> >> I'm using Enchant version 2.3.1 and an Emacs 29 build from 24 November
> >> on macOS Catalina.
> >
> > Which dictionary do you use, and what encoding does that dictionary
> > require?
> 
> In Emacs, the relevant entry in `ispell-dictionary-alist' is
> 
>   ("en" "[[:alpha:]]" "[^[:alpha:]]" "" t nil nil utf-8)
> 
> I installed `aspell' and `enchant' from Homebrew.  The installation of
> `aspell' included a bunch of dictionaries downloaded from gnu.org.  In
> particular, the "en" dictionary is downloaded from [1].  It is in some
> kind of binary format after installation (see [2] for details).
> 
> The weird part is that it works fine in a command line, and switching
> `ispell-program-name' to use `aspell' fixes the issue, so the problem
> seems to be somehow in how Emacs interacts with the `enchant-2' binary.
> It's doing the same for non-ASCII characters as one would expect from
> numbers: the string "one0two" is valid, as "one" and "two" are treated
> as separate words and "0" is ignored.

I suspect that the problem is with the LC_* and LANG environment
variables in the problematic case, which confuse the speller with
regards to the language and encoding used.