bug#27919: 25.2.50; dired + eshell-ls: fallback to external ls fails

[Tino Calancha]

On Wed, 2 Aug 2017, John Wiegley wrote:

> > > > > > "TC" == Tino Calancha <tino.calancha@gmail.com> writes:
>
> TC> M-: (dired source-directory "-lg") RET
> TC> ;; Signal eshell-interactive-output-p: (wrong-type-argument arrayp nil)
>
> Why would eshell be involving with using dired at all?  Do you have a
> customization present that is causing this?
Not me.  I am just testing all the functionality available.
Someone added in 2000 a defcustom `eshell-ls-use-in-dired', so 
that you can run eshell-ls to list directories with Dired.

Now i understand why i get this error: the dired support was added
'a posteriori'.

I think an user who want to set `eshell-ls-use-in-dired' non-nil is
likely someone with no external 'ls' installed.