At the moment, PM does not prevent a computer from sleeping, even if PM is running a task.
Since scanning catalogs can a long time, I usually get them started and go do other things, or leave them to run over night. Seems to me it is pretty much mandatory that the computer is kelp awake while running a task.
Our developers are still on holiday vacation this week, so I'm going to go ahead and mark this as something we may consider in the future, but I may need to revise them later with more info.
Another comment regarding this request. I originally posted this topic to the support page but was told to post a feature request here. But honestly, I can’t imagine how this can be considered a “feature”. If the computer is allowed to sleep while the software is actively running a task, isn’t that a bug? Surely keeping the computer awake has to be considered mandatory and not a “feature”.
For example, what if:
Photoshop allowed the computer to fall asleep while batch-processing images.
A video player allowed the computer to fall asleep while watching a movie.
A web browser allowed the computer to fall asleep in the middle of a download.
I think most people would consider those bugs. Not sure why PM is any different.
Either way, posting it here allows us to see how popular the idea is for prioritization.
FYI, "Amphetamine" is a really handy and powerful macOS app that can prevent your Mac from falling asleep. It's a great work-around for apps that don't natively support this feature.