[GNC] Uninstalling previous versions

[Geert Janssens]

Op dinsdag 3 juli 2018 04:48:21 CEST schreef Thomas Forrester:

> > > Totally agree.  Windows in not entirely free of messy installers, far
> > > from it, but the vast majority of installers take care of the
> > > prerequisites, including suspending the installation waiting for the
> > > user to close a program that's trying to upgrade itself.  At a minimum
> > > any installer worth its salt should be able to check existing files
> > > against a manifest of valid files for the currently installing version,
> > > and delete anything conflicting.
> > > 
I'm not that well versed with Windows installers but I don't think what you 
describe is how they actually work. As far as I understand an installer will 
indeed create some kind of install manifest. This manifest will be used to 
remove these files again before installing the new ones. But the new installer 
itself does not come with a list of files from older versions that at some 
point have become obsolete. It also is not aware of optional files as far as I 
know.
Our installer has been configured for quite a while already to first delete an 
existing gnucash installation before installing the new one. I have no idea 
why this sometimes still leaves old files lingering. Perhaps the installer 
internally uses some heuristics to only delete files it believes have really 
changed or are gone. And perhaps this fails because we completely changed 
build systems on Windows which confuses these heuristics.

If you see ways to improve our installer you are encouraged to send in a patch 
or PR... It would certainly be appreciated.

Regards,

Geert