Sometimes we can get on a system that have all mixed up: Multiple repos of different vendors enabled and you get all mixed up, a kind of "2 OS 1 Host".
A common scenario I see is a RHEL-Oracle with mixed up system packages as an non-versed sysadmin enable Oracle OS repos and DB repos to install an Oracle DB.
So it will be useful to get some kind of alert on this cases.
A quick way to detect this kind of issues is to see for more than one {vendorname}-release file in /etc. Is not always there, but as you already do that work, could be useful to see if there is more than one and put a warning.
If you're ok with this I could try to work this patch up and make a pull request.
Sometimes we can get on a system that have all mixed up: Multiple repos of different vendors enabled and you get all mixed up, a kind of "2 OS 1 Host". A common scenario I see is a RHEL-Oracle with mixed up system packages as an non-versed sysadmin enable Oracle OS repos and DB repos to install an Oracle DB. So it will be useful to get some kind of alert on this cases. A quick way to detect this kind of issues is to see for more than one {vendorname}-release file in /etc. Is not always there, but as you already do that work, could be useful to see if there is more than one and put a warning. If you're ok with this I could try to work this patch up and make a pull request.