NOTE 2: The 0x0 (empty matrix) is represented as en empty array inside an array [[]]. description clearly states what to do with such input (it probably was added after all those comments), so there's no issue with kata in this regard.

@FArekkusu Could you emplain why? :/

Not an issue, everything works correctly.

Not a question.

I was stuck on this for a long time because instead of an exception I was getting a timeout... my code went into an infinite loop because the "empty" matrix has one row of zero elements, which is NOT a square.

The answer should be an array with an empty array on it for the empty matrix

See the last 2 (and many more) posts on this page. This kata has a very strange definition of how an empty matrix should be represented.

IMHO the kata is broken.

I see a picture from one of my favorite games and meme/pun next to it - instant upvote! :D

(Unless you are asking seriously?)