duplicate!

Please, don't ever use Test.expect() without a customized error message upon failure. The default error message shown to the user when Test.expect() fails is "Value is not what was expected" which provides no useful feedback whatsoever for debugging. Even adding a simple message as "The 3 by 3 matrix [[1,1,1], [1,1,1], [1,1,1]] is not a magic square!" (upon failure) would be helpful.

Your Kata needs more extensive test coverage to prevent easy cheap-cheat solutions and/or logically flawed solutions. The most common way to increase test coverage is through the inclusion of randomly generated test cases at runtime so please add these. The lack of test coverage in a Kata as an Issue is recognised as an official CW stance.