Bug#714175: /etc/profile.d/vte.sh: Should not override an existing PROMPT_COMMAND

[Christoph Anton Mitterer]

Hey.

Regarding this issue...

What upstream currently plans to do (see
https://gitlab.gnome.org/GNOME/vte/-/issues/37 ) still breaks an
existing PROMPT_COMMAND, unless it exists already as a variable.

See my comments about the situation in:
[0] https://gitlab.gnome.org/GNOME/vte/-/issues/37#note_1280913


I've independently proposed another way how to handle this in:
https://gitlab.gnome.org/GNOME/vte/-/issues/2502
respectively:
https://gitlab.gnome.org/calestyo/vte/-/commit/06431d0ea7e8d27f95bbeda933958ba29043e19e

Which, AFAICS, handles all (realistic) cases properly with bash
versions that support PROMPT_COMMAND as an array (that is: all versions
Debian currently has since buster).

Realistic refers to the fact, that a user might do weird things, like
using name refs or defining PROMPT_COMMAND an associative array... but
for the former it may even work, and for the latter PROMPT_COMMAND
itself doesn't work at all as an associative array.
So that shouldn't be a problem.


I should note however that upstream rejected my proposed patch:
https://gitlab.gnome.org/GNOME/vte/-/issues/2502#note_1203193

But I don't really understand why. Their arguing seem to be that they
want to add another command to PROMPT_COMMAND depending on whether it's
an array or not:
- if it is an array, add a command that only handles OSC7
- if it's not, add one that does both OSC7 and window titles

As I discuss in [0], this doesn't make sense (or I just don't
understand it ^^).
But anyway... in Debian, window titles are anyway handled by bashrc's
setting of PS1.



Cheers,
Chris.


btw: OSC7 has IMO anyway security implications:
https://gitlab.freedesktop.org/terminal-wg/specifications/-/issues/20#note_956242

So IMO it should be anyway disabled in the code (wouldn't be enough to
disable the profile.d script)