uninstall_package judged success by searching apt/dnf/apk/pacman output
for failure words. That is guesswork in both directions: apt's commonest
failure ("E: Sub-process /usr/bin/dpkg returned an error code (1)") read
as success until the previous change, and a prerm that prints "Failed to
stop ..." while the removal completes still reads as failure. The exit
status is the answer the package manager actually gives, but every
command went through `_sudo(... || true)`, which throws it away.
Add `_sudo_status()`, which runs the command via `_sudo` followed by
`; echo __NETORK_RC=$?` and returns `(output, exit_status)` with the
marker stripped. The `|| true` of other `_sudo` callers is untouched:
they still want output rather than a status. The marker is matched only
on a line of its own with digits, so an echoed command line (literal
`$?`) is never mistaken for it. If the marker never arrives the status
is None -- unknown, not success.
uninstall_package and its dpkg fallback now use it, and
`_uninstall_failed(output, rc)` lets rc decide whenever it is known,
falling back to the keyword check only when it is not.
Behaviour change worth knowing: removing a package that is not installed
exits 0 on apt (and dnf), so it now reports success where the keyword
"is not installed" used to report failure. The package is absent
afterwards, which is what the caller asked for, and netOrk dropping it
from the installed record is then correct.
Refs christianmanivong/netork#267
Christian Manivong
ac288823a7