>> Isn't that what it does now? If it cannot install the new version because of a filename conflict, then it tells the user they must force it (which would rename the conflicts rather than destroy them).
> Yeah, that's what it does.
> But to reach that point it first uninstalls the old version and then only notices that that port had installed other stuff in the directory in question.
> By that time it already doesn't matter anymore that the new port does not get installed, since all the data of the previous version is already gone and there is no easy way back.
Why is "all the data" gone? Are you saying that some of the files installed by and registered to the port are files the user modifies? If so, that is a bug in the port that must be fixed.