Well, there's Chess Position Trainer, which is pretty much exactly what you want, but you would have to come up with a way to make it work on Mac. I don't know of an equivalent for mac, but maybe someone else will be along to help.
CPT is miraculous for the function you want. Has changed my chess life.
Hi,
I am looking for a good way to train on various openings and opening lines. I watch a lot of videos but I feel like forcing myself to respond to openings on the board is the best way to really learn and have things stick. Ideally I would like a tool (program/software/website) where I can choose an opening to start for either white or black and then have the program/engine tell me when I respond incorrectly to a line. Also if I could customize a repetoire, that would be desirable. I use a Mac and I have an iPad. I did see one program for iPad called "Chess Opening Trainer" but the reviews are mixed.
Thanks for your suggestions!
Pat