Re: INSIDE_EMACS and Tramp (was: master f28166d: Copy INSIDE_EMACS env variable to subprocesses in Eshell (Bug#25496))

[Federico Tedin <federicotedin@gmail.com>]

Hey Michael, some questions:

> --8<---------------cut here---------------start------------->8---
> (let ((default-directory "/ssh::"))
>   (shell-command-to-string "echo $INSIDE_EMACS"))
> --8<---------------cut here---------------end--------------->8---
>
> you get "28.0.50,tramp:2.5.0-pre". But if you run in an eshell buffer

Would it make sense to change this to "28.0.50,,tramp:2.5.0-pre"
(notice the extra comma), or "28.0.50,shell,tramp:2.5.0-pre"?
This way, the second element in the list will always be the shell
type, and the optional third will be the Tramp version. Though I'm
not sure if "shell" would correspond to "shell-command-to-string".

> --8<---------------cut here---------------start------------->8---
> ~/src/emacs $ cd /ssh::
> /ssh:detlef:/home/albinus $ *echo $INSIDE_EMACS
> --8<---------------cut here---------------end--------------->8---
>
> you get "28.0.50,eshell". Tramp's setting is overwritten.
>
> Shouldn't the specifics be merged, so that we get
> "28.0.50,eshell,tramp:2.5.0-pre"?
>
> Same for the other packages setting INSIDE_EMACS, like compile, comint,
> term and epg.

I could maybe start working on adding this for Eshell (now that I more
or less know how it internally handles variables) if you think that
makes sense.

- Fede