Should I write unit test for everything?

Question

I am wondering should I write unit test for everything. There are some classes is very difficult to write unit test. For example, I am writing some program for handling audi

Answer 1

Code that capture and replay audio cannot be unit-tested (albeit you could test that the capture method returns an error when called when the class isn't successfully bound to a resource).

However, unless you simply write the captured sound to disk the code that invokes your capture and play classes certainly can.

Two pieces of advice:

• Don't test the compiler (e.g. getter and setter)
• Test everything that could possibly break