Really bad form, testing students on things they may or may have not been taught (particularly in an undergrad class). Lessons often give something off about how/what the teacher thinks important which leads to how the testing will go.
The worst class I ever took was a required freshman English. The person teaching it was not a native speaker and although she knew the parts of sentence she was totally clueless on the culture. Women got marked down if papers weren't focused on traditionally female interests (eg. cooking, sewing) and the same for men (sports, home repair). I remember one class in particular when she wanted one of the guys to describe the track suit that he had seen his teacher wearing in a class he had earlier in the day. It took several minutes to explain that the other teacher didn't wear a tie with it.