It is well known that perch doesn't upscale images. I can live with that (although I'm not a fan; a valid use case for upscaling would be https://www.filamentgroup.com/lab/compressive-images.html).
The problem we're currently facing is that not only scaling, but also cropping fails silently when the provided image is too small. So we get a lot of misproportioned imagery on the site, breaking the layout. As images used on the web get larger (we use a srcset with 1200, 800 and around 500px), this happens often. We have to correct that either manually or with object-fit.
So the difference to what happens when perch fails silently to upSCALE only is that it hurts more when it does so for cropping.
I would like to suggest those three variants for your consideration:
- Allow upscaling for cropping (as it hurts more when it fails)
OR an "enable the upscaling although it's bad practice" setting
OR Display a warning / fail loudly when an image cropping couldn't be carried out