GUI CLI integration missing non-zero exit codes

[deeplow]

How to file a helpful issue

Qubes OS release

4.2

Brief summary

Calling the GUI updater from the CLI always exits with zero even if some update failed.

Steps to reproduce

1. qubes-update-gui --restart
2. If any update failed or the user exited without restarting qubes, confirm that exit code is still zero

Expected behavior

Have failures consistent with CLI updater counterpart: after any failure, the exit code would be non-zero.

Extra caveat: what to do when user bailed on updates / restarts? (here are my takes)

• --targets was provided but user closed the updater before all updates were applied (exit non-zero)
• --restart was forced via CLI but the user closed the updater before restarts were applied (blocked on GUI CLI integration "--restart" does not force restarts #9032)

(If possible, the above exit codes are different to disambiguate)

Actual behavior

The GUI updater always exits with zero