In CS1 I have students do manual testing. I try to drive home the point that you don’t know that your program works until you have tested it. Unit testing is a whole additional topic though and I like to push it back a little.

I will also note that my desire to have students learn using a statically typed language also mainly applies to students who are going to go on to do more programming. If they aren’t going to become developers, I feel much less strongly about it.