Adding a comment there is not useful, it should be added only in the function definition if needed. In this case it’s needed because the function does something

Adding a comment there is not useful, it should be added only in the function definition if needed. In this case it’s needed because the function does something unexpected. I would call it nextPower2(n) rather than npow2 and add a comment in the definition saying that the function returns n if n is a power of 2 because it’s unexpected and it can’t be inferred looking at the function name. As I said before, comments for unexpected behaviours are not only perfectly fine but extremely important. Also removing all the useless comments will increase the relative importance of the ones remaining since you will have only comments for really important stuff. Edit: And anyway in the tests you should have at least these two test cases: Test nextPower2 returns n if it’s a power of 2 Test nextPower2 returns the next power of 2 if n is not a power of 2