Implement check command

[mcurlej]

• Command: check

• --dependencies

• --duplicates

• --obsoleted

• --provides - After discussions, this option was removed as nonsense.

dnf [options] check [--dependencies] [--duplicates] [--obsoleted]

Checks the local packagedb and produces information on any problems it finds. You can limit the checks to be performed by using the --dependencies, --duplicates and --obsoleted options (the default is to check everything).

[j-mracek]

It would be interesting to investigate whether RPM is providing such tests. If the functionality is in RPM then direct usage without DNF will help to resolve the use case when DNF is broken. If RPM gets broken then there is no way how to resolve it.

[ppisar]

What does "dnf check" do?
If "dnf check --duplicates" reports packages which are installed in multiple versions, e.g. after a crashed RPM transaction when both PACKAGE-1 and PACKAGE-2 are left, then there must be more logic because of installonly (kernel) packages. Although "rpm --dupes" does not report "kernel" for me. Maybe it does something else.

[jrohel]

@ppisar
--duplicites lists duplicate installed packages (same name and architecture), installonly packages should be excluded from the list.
An example on my intentionally damaged system:

# dnf check --duplicates 
pipewire-0.3.80-1.fc39.x86_64 is a duplicate with pipewire-0.3.84-3.fc39.x86_64
pipewire-pulseaudio-0.3.80-1.fc39.x86_64 is a duplicate with pipewire-pulseaudio-0.3.84-3.fc39.x86_64
Error: Check discovered 2 problem(s)

[jrohel]

I don't know what exactly the purpose of --provides is. It tests that the "provides" of the installed packages are really installed. Is the goal to detect errors in the implementation? Do we really want this test here?