Comment # 7 on bug 1155819 from Ludwig Nussel

(In reply to Michael Andres from comment #5)
> Now it's obvious. YAST and migrations scripts explicitly select the products
> in addition to dup, that's why it works for them (they'd select "openSUSE
> Leap 15.2" before the solver run).
> 
> On a plain zypper dup however "openSUSE Leap 15.2" is not yet selected. We'd
> need 2 passes (one to compute the product fates and a 2nd one after adding
> the weakremovers)....

At least it would make sense if yast and zypper did the same. Couldn't libsolv
handle that itself?