Test for NSLog output

Question

I'm writing a framework that also includes a simple logger that can be enabled/disabled at runtime. Since I want have unit tests for as much of the framework as possible, I also want to test whether the logger works correctly.

The logger simply logs via NSLog. Now I need to test whether the output really matches the expectation (i.e. does it really log and is the output in the correct format). I couldn't find a way to do that using Xcode's XCTest framework.

I could modify the logger so that it doesn't use NSLog while testing but that strikes me as error-prone. So, is there a better way to check the NSLog output?

Answer 1

Have the logger output strings. Have another object print these. This way you can unit test the first object separately from the second.