i'm also a computer programmer and i just took a semester of Java, C++ and C.
To be honest, and i hate to tell you, but i would recommend you a PC......

There are programs such as secure shell clients that doesn't work with macs which allows you to configure your codes. so instead we(macs) had to find alternatives for them and it was a pain in the ass to find a good one. But if you're willing to take time and use your mac like i did and suffer the pain, get the macbook. screen size isn't a must, although it'll help you observe your codes, mobility is way more important, and 2 inches isn't a big deal. as you go through difficult codes, you're going to need help and having your laptop with you in campus will be a benefit.